v3.9.3

fixes #3891

.github/workflows/ci.yml

@@ -8,6 +8,8 @@ jobs:
         os: [ ubuntu-latest, windows-latest ]
         script: [ compress, mocha, release/benchmark, release/jetstream ]
         exclude:
+          - node: "0.8"
+            script: release/benchmark
           - node: "0.8"
             script: release/jetstream
     name: ${{ matrix.node }} ${{ matrix.os }} ${{ matrix.script }}
@@ -16,7 +18,7 @@ jobs:
       NODE: ${{ matrix.node }}
       TYPE: ${{ matrix.script }}
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v2
       - uses: actions/cache@v1
         with:
           path: tmp

.github/workflows/ufuzz.yml

@@ -1,7 +1,7 @@
 name: Fuzzing
 on:
   schedule:
-    - cron: "*/15 * * * *"
+    - cron: "*/8 * * * *"
 jobs:
   ufuzz:
     strategy:
@@ -11,7 +11,7 @@ jobs:
     name: ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v2
       - name: Perform fuzzing
         shell: bash
         run: |

README.md

@@ -4,8 +4,8 @@ UglifyJS 3
 UglifyJS is a JavaScript parser, minifier, compressor and beautifier toolkit.
 
 #### Note:
-- **`uglify-js@3` has a simplified [API](#api-reference) and [CLI](#command-line-usage) that is not backwards compatible with [`uglify-js@2`](https://github.com/mishoo/UglifyJS2/tree/v2.x)**.
-- **Documentation for UglifyJS `2.x` releases can be found [here](https://github.com/mishoo/UglifyJS2/tree/v2.x)**.
+- **`uglify-js@3` has a simplified [API](#api-reference) and [CLI](#command-line-usage) that is not backwards compatible with [`uglify-js@2`](https://github.com/mishoo/UglifyJS/tree/v2.x)**.
+- **Documentation for UglifyJS `2.x` releases can be found [here](https://github.com/mishoo/UglifyJS/tree/v2.x)**.
 - `uglify-js` only supports JavaScript (ECMAScript 5).
 - To minify ECMAScript 2015 or above, transpile using tools like [Babel](https://babeljs.io/).
 
@@ -126,6 +126,7 @@ a double dash to prevent input files being used as option arguments:
                                 `includeSources`  Pass this flag if you want to include
                                                   the content of source files in the
                                                   source map as sourcesContent property.
+                                `names` Include symbol names in the source map.
                                 `root`  Path to the original source to be included in
                                         the source map.
                                 `url`  If specified, path to the source map to append in
@@ -159,6 +160,9 @@ Additional options:
 
 - `--source-map "root='<URL>'"` to pass the URL where the original files can be found.
 
+- `--source-map "names=false"` to omit symbol names if you want to reduce size
+  of the source map file.
+
 - `--source-map "url='<URL>'"` to specify the URL where the source map can be found.
   Otherwise UglifyJS assumes HTTP `X-SourceMap` is being used and will omit the
   `//# sourceMappingURL=` directive.
@@ -593,6 +597,9 @@ var result = UglifyJS.minify({"compiled.js": "compiled code"}, {
 
 If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.url`.
 
+If you wish to reduce file size of the source map, set option `sourceMap.names`
+to be `false` and all symbol names will be omitted.
+
 ## Parse options
 
 - `bare_returns` (default `false`) -- support top level `return` statements
@@ -906,7 +913,7 @@ can pass additional arguments that control the code output:
 
 - `wrap_iife` (default `false`) -- pass `true` to wrap immediately invoked
   function expressions. See
-  [#640](https://github.com/mishoo/UglifyJS2/issues/640) for more details.
+  [#640](https://github.com/mishoo/UglifyJS/issues/640) for more details.
 
 # Miscellaneous
 
@@ -1065,8 +1072,8 @@ var result = UglifyJS.minify(ast, {
 ### Working with Uglify AST
 
 Transversal and transformation of the native AST can be performed through
-[`TreeWalker`](https://github.com/mishoo/UglifyJS2/blob/master/lib/ast.js) and
-[`TreeTransformer`](https://github.com/mishoo/UglifyJS2/blob/master/lib/transform.js)
+[`TreeWalker`](https://github.com/mishoo/UglifyJS/blob/master/lib/ast.js) and
+[`TreeTransformer`](https://github.com/mishoo/UglifyJS/blob/master/lib/transform.js)
 respectively.
 
 ### ESTree / SpiderMonkey AST

bin/uglifyjs

@@ -23,12 +23,29 @@ program.parse = undefined;
 if (process.argv.indexOf("ast") >= 0) program.helpInformation = UglifyJS.describe_ast;
 else if (process.argv.indexOf("options") >= 0) program.helpInformation = function() {
     var text = [];
+    var toplevels = [];
+    var padding = "";
     var options = UglifyJS.default_options();
-    for (var option in options) {
-        text.push("--" + (option == "output" ? "beautify" : option == "sourceMap" ? "source-map" : option) + " options:");
-        text.push(format_object(options[option]));
-        text.push("");
+    for (var name in options) {
+        var option = options[name];
+        if (option && typeof option == "object") {
+            text.push("--" + ({
+                output: "beautify",
+                sourceMap: "source-map",
+            }[name] || name) + " options:");
+            text.push(format_object(option));
+            text.push("");
+        } else {
+            if (padding.length < name.length) padding = Array(name.length + 1).join(" ");
+            toplevels.push([ {
+                keep_fnames: "keep-fnames",
+                nameCache: "name-cache",
+            }[name] || name, option ]);
+        }
     }
+    toplevels.forEach(function(tokens) {
+        text.push("--" + tokens[0] + padding.slice(tokens[0].length - 2) + tokens[1]);
+    });
     return text.join("\n");
 };
 program.option("-p, --parse <options>", "Specify parser options.", parse_js());
@@ -51,6 +68,7 @@ program.option("--self", "Build UglifyJS as a library (implies --wrap UglifyJS)"
 program.option("--source-map [options]", "Enable source map/specify source map options.", parse_js());
 program.option("--timings", "Display operations run time on STDERR.");
 program.option("--toplevel", "Compress and/or mangle variables in toplevel scope.");
+program.option("--validate", "Perform validation during AST manipulations.");
 program.option("--verbose", "Print diagnostic messages.");
 program.option("--warn", "Print warning messages.");
 program.option("--wrap <name>", "Embed everything as a function with “exports” corresponding to “name” globally.");
@@ -74,6 +92,7 @@ if (!program.output && program.sourceMap && program.sourceMap.url != "inline") {
     "mangle",
     "sourceMap",
     "toplevel",
+    "validate",
     "wrap"
 ].forEach(function(name) {
     if (name in program) {
@@ -220,7 +239,10 @@ function run() {
         // load on demand - assumes dev tree checked out
         var reduce_test = require("../test/reduce");
         var testcase = files[0] || files[Object.keys(files)[0]];
-        var result = reduce_test(testcase, options, {verbose: true});
+        var result = reduce_test(testcase, options, {
+            log: print_error,
+            verbose: true,
+        });
     }
     else {
         var result = UglifyJS.minify(files, options);

lib/ast.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -110,12 +110,16 @@ var AST_Node = DEFNODE("Node", "start end", {
         start: "[AST_Token] The first token of this node",
         end: "[AST_Token] The last token of this node"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this);
-    },
     walk: function(visitor) {
-        return this._walk(visitor); // not sure the indirection will be any help
-    }
+        visitor.visit(this);
+    },
+    _validate: noop,
+    validate: function() {
+        var ctor = this.CTOR;
+        do {
+            ctor.prototype._validate.call(this);
+        } while (ctor = ctor.BASE);
+    },
 }, null);
 
 (AST_Node.log_function = function(fn, verbose) {
@@ -138,6 +142,32 @@ var AST_Node = DEFNODE("Node", "start end", {
     }
 })();
 
+var restore_transforms = [];
+AST_Node.enable_validation = function() {
+    AST_Node.disable_validation();
+    (function validate_transform(ctor) {
+        var transform = ctor.prototype.transform;
+        ctor.prototype.transform = function(tw, in_list) {
+            var node = transform.call(this, tw, in_list);
+            if (node instanceof AST_Node) {
+                node.validate();
+            } else if (!(node === null || in_list && List.is_op(node))) {
+                throw new Error("invalid transformed value: " + node);
+            }
+            return node;
+        };
+        restore_transforms.push(function() {
+            ctor.prototype.transform = transform;
+        });
+        ctor.SUBCLASSES.forEach(validate_transform);
+    })(this);
+};
+
+AST_Node.disable_validation = function() {
+    var restore;
+    while (restore = restore_transforms.pop()) restore();
+};
+
 /* -----[ statements ]----- */
 
 var AST_Statement = DEFNODE("Statement", null, {
@@ -154,23 +184,37 @@ var AST_Directive = DEFNODE("Directive", "value quote", {
         value: "[string] The value of this directive as a plain string (it's not an AST_String!)",
         quote: "[string] the original quote character"
     },
+    _validate: function() {
+        if (typeof this.value != "string") throw new Error("value must be string");
+    },
 }, AST_Statement);
 
+function must_be_expression(node, prop) {
+    if (!(node[prop] instanceof AST_Node)) throw new Error(prop + " must be AST_Node");
+    if (node[prop] instanceof AST_Statement && !(node[prop] instanceof AST_Function)) {
+        throw new Error(prop + " cannot be AST_Statement");
+    }
+}
+
 var AST_SimpleStatement = DEFNODE("SimpleStatement", "body", {
     $documentation: "A statement consisting of an expression, i.e. a = 1 + 2",
     $propdoc: {
         body: "[AST_Node] an expression node (should not be instanceof AST_Statement)"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.body._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.body.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "body");
+    },
 }, AST_Statement);
 
 function walk_body(node, visitor) {
     node.body.forEach(function(node) {
-        node._walk(visitor);
+        node.walk(visitor);
     });
 }
 
@@ -179,11 +223,18 @@ var AST_Block = DEFNODE("Block", "body", {
     $propdoc: {
         body: "[AST_Statement*] an array of statements"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            walk_body(this, visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            walk_body(node, visitor);
         });
-    }
+    },
+    _validate: function() {
+        this.body.forEach(function(node) {
+            if (!(node instanceof AST_Statement)) throw new Error("body must be AST_Statement[]");
+            if (node instanceof AST_Function) throw new Error("body cannot contain AST_Function");
+        });
+    },
 }, AST_Statement);
 
 var AST_BlockStatement = DEFNODE("BlockStatement", null, {
@@ -198,7 +249,11 @@ var AST_StatementWithBody = DEFNODE("StatementWithBody", "body", {
     $documentation: "Base class for all statements that contain one nested body: `For`, `ForIn`, `Do`, `While`, `With`",
     $propdoc: {
         body: "[AST_Statement] the body; this should always be present, even if it's an AST_EmptyStatement"
-    }
+    },
+    _validate: function() {
+        if (!(this.body instanceof AST_Statement)) throw new Error("body must be AST_Statement");
+        if (this.body instanceof AST_Function) throw new Error("body cannot be AST_Function");
+    },
 }, AST_Statement);
 
 var AST_LabeledStatement = DEFNODE("LabeledStatement", "label", {
@@ -206,10 +261,11 @@ var AST_LabeledStatement = DEFNODE("LabeledStatement", "label", {
     $propdoc: {
         label: "[AST_Label] a label definition"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.label._walk(visitor);
-            this.body._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.label.walk(visitor);
+            node.body.walk(visitor);
         });
     },
     clone: function(deep) {
@@ -225,7 +281,10 @@ var AST_LabeledStatement = DEFNODE("LabeledStatement", "label", {
             }));
         }
         return node;
-    }
+    },
+    _validate: function() {
+        if (!(this.label instanceof AST_Label)) throw new Error("label must be AST_Label");
+    },
 }, AST_StatementWithBody);
 
 var AST_IterationStatement = DEFNODE("IterationStatement", null, {
@@ -236,25 +295,30 @@ var AST_DWLoop = DEFNODE("DWLoop", "condition", {
     $documentation: "Base class for do/while statements",
     $propdoc: {
         condition: "[AST_Node] the loop condition.  Should not be instanceof AST_Statement"
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "condition");
+    },
 }, AST_IterationStatement);
 
 var AST_Do = DEFNODE("Do", null, {
     $documentation: "A `do` statement",
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.body._walk(visitor);
-            this.condition._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.body.walk(visitor);
+            node.condition.walk(visitor);
         });
     }
 }, AST_DWLoop);
 
 var AST_While = DEFNODE("While", null, {
     $documentation: "A `while` statement",
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.condition._walk(visitor);
-            this.body._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.condition.walk(visitor);
+            node.body.walk(visitor);
         });
     }
 }, AST_DWLoop);
@@ -266,14 +330,26 @@ var AST_For = DEFNODE("For", "init condition step", {
         condition: "[AST_Node?] the `for` termination clause, or null if empty",
         step: "[AST_Node?] the `for` update clause, or null if empty"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            if (this.init) this.init._walk(visitor);
-            if (this.condition) this.condition._walk(visitor);
-            if (this.step) this.step._walk(visitor);
-            this.body._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            if (node.init) node.init.walk(visitor);
+            if (node.condition) node.condition.walk(visitor);
+            if (node.step) node.step.walk(visitor);
+            node.body.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        if (this.init != null) {
+            if (!(this.init instanceof AST_Node)) throw new Error("init must be AST_Node");
+            if (this.init instanceof AST_Statement
+                && !(this.init instanceof AST_Definitions || this.init instanceof AST_Function)) {
+                throw new Error("init cannot be AST_Statement");
+            }
+        }
+        if (this.condition != null) must_be_expression(this, "condition");
+        if (this.step != null) must_be_expression(this, "step");
+    },
 }, AST_IterationStatement);
 
 var AST_ForIn = DEFNODE("ForIn", "init object", {
@@ -282,13 +358,22 @@ var AST_ForIn = DEFNODE("ForIn", "init object", {
         init: "[AST_Node] the `for/in` initialization code",
         object: "[AST_Node] the object that we're looping through"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.init._walk(visitor);
-            this.object._walk(visitor);
-            this.body._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.init.walk(visitor);
+            node.object.walk(visitor);
+            node.body.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        if (this.init instanceof AST_Definitions) {
+            if (this.init.definitions.length != 1) throw new Error("init must have single declaration");
+        } else if (!(this.init instanceof AST_PropAccess || this.init instanceof AST_SymbolRef)) {
+            throw new Error("init must be assignable");
+        }
+        must_be_expression(this, "object");
+    },
 }, AST_IterationStatement);
 
 var AST_With = DEFNODE("With", "expression", {
@@ -296,12 +381,16 @@ var AST_With = DEFNODE("With", "expression", {
     $propdoc: {
         expression: "[AST_Node] the `with` expression"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.expression._walk(visitor);
-            this.body._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.expression.walk(visitor);
+            node.body.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "expression");
+    },
 }, AST_StatementWithBody);
 
 /* -----[ scope and functions ]----- */
@@ -326,7 +415,12 @@ var AST_Scope = DEFNODE("Scope", "variables functions uses_with uses_eval parent
     },
     pinned: function() {
         return this.uses_eval || this.uses_with;
-    }
+    },
+    _validate: function() {
+        if (this.parent_scope != null) {
+            if (!(this.parent_scope instanceof AST_Scope)) throw new Error("parent_scope must be AST_Scope");
+        }
+    },
 }, AST_Block);
 
 var AST_Toplevel = DEFNODE("Toplevel", "globals", {
@@ -380,27 +474,44 @@ var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments length_read", {
         argnames: "[AST_SymbolFunarg*] array of function arguments",
         uses_arguments: "[boolean/S] tells whether this function accesses the arguments array"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            if (this.name) this.name._walk(visitor);
-            this.argnames.forEach(function(argname) {
-                argname._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            if (node.name) node.name.walk(visitor);
+            node.argnames.forEach(function(argname) {
+                argname.walk(visitor);
             });
-            walk_body(this, visitor);
+            walk_body(node, visitor);
         });
-    }
+    },
+    _validate: function() {
+        this.argnames.forEach(function(node) {
+            if (!(node instanceof AST_SymbolFunarg)) throw new Error("argnames must be AST_SymbolFunarg[]");
+        });
+    },
 }, AST_Scope);
 
 var AST_Accessor = DEFNODE("Accessor", null, {
-    $documentation: "A setter/getter function.  The `name` property is always null."
+    $documentation: "A setter/getter function.  The `name` property is always null.",
+    _validate: function() {
+        if (this.name != null) throw new Error("name must be null");
+    },
 }, AST_Lambda);
 
 var AST_Function = DEFNODE("Function", "inlined", {
-    $documentation: "A function expression"
+    $documentation: "A function expression",
+    _validate: function() {
+        if (this.name != null) {
+            if (!(this.name instanceof AST_SymbolLambda)) throw new Error("name must be AST_SymbolLambda");
+        }
+    },
 }, AST_Lambda);
 
 var AST_Defun = DEFNODE("Defun", "inlined", {
-    $documentation: "A function definition"
+    $documentation: "A function definition",
+    _validate: function() {
+        if (!(this.name instanceof AST_SymbolDefun)) throw new Error("name must be AST_SymbolDefun");
+    },
 }, AST_Lambda);
 
 /* -----[ JUMPS ]----- */
@@ -414,19 +525,26 @@ var AST_Exit = DEFNODE("Exit", "value", {
     $propdoc: {
         value: "[AST_Node?] the value returned or thrown by this statement; could be null for AST_Return"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, this.value && function() {
-            this.value._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            if (node.value) node.value.walk(visitor);
         });
     }
 }, AST_Jump);
 
 var AST_Return = DEFNODE("Return", null, {
-    $documentation: "A `return` statement"
+    $documentation: "A `return` statement",
+    _validate: function() {
+        if (this.value != null) must_be_expression(this, "value");
+    },
 }, AST_Exit);
 
 var AST_Throw = DEFNODE("Throw", null, {
-    $documentation: "A `throw` statement"
+    $documentation: "A `throw` statement",
+    _validate: function() {
+        must_be_expression(this, "value");
+    },
 }, AST_Exit);
 
 var AST_LoopControl = DEFNODE("LoopControl", "label", {
@@ -434,11 +552,17 @@ var AST_LoopControl = DEFNODE("LoopControl", "label", {
     $propdoc: {
         label: "[AST_LabelRef?] the label, or null if none",
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, this.label && function() {
-            this.label._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            if (node.label) node.label.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        if (this.label != null) {
+            if (!(this.label instanceof AST_LabelRef)) throw new Error("label must be AST_LabelRef");
+        }
+    },
 }, AST_Jump);
 
 var AST_Break = DEFNODE("Break", null, {
@@ -457,13 +581,21 @@ var AST_If = DEFNODE("If", "condition alternative", {
         condition: "[AST_Node] the `if` condition",
         alternative: "[AST_Statement?] the `else` part, or null if not present"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.condition._walk(visitor);
-            this.body._walk(visitor);
-            if (this.alternative) this.alternative._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.condition.walk(visitor);
+            node.body.walk(visitor);
+            if (node.alternative) node.alternative.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "condition");
+        if (this.alternative != null) {
+            if (!(this.alternative instanceof AST_Statement)) throw new Error("alternative must be AST_Statement");
+            if (this.alternative instanceof AST_Function) throw new error("alternative cannot be AST_Function");
+        }
+    },
 }, AST_StatementWithBody);
 
 /* -----[ SWITCH ]----- */
@@ -473,12 +605,16 @@ var AST_Switch = DEFNODE("Switch", "expression", {
     $propdoc: {
         expression: "[AST_Node] the `switch` “discriminant”"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.expression._walk(visitor);
-            walk_body(this, visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.expression.walk(visitor);
+            walk_body(node, visitor);
         });
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "expression");
+    },
 }, AST_Block);
 
 var AST_SwitchBranch = DEFNODE("SwitchBranch", null, {
@@ -494,12 +630,16 @@ var AST_Case = DEFNODE("Case", "expression", {
     $propdoc: {
         expression: "[AST_Node] the `case` expression"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.expression._walk(visitor);
-            walk_body(this, visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.expression.walk(visitor);
+            walk_body(node, visitor);
         });
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "expression");
+    },
 }, AST_SwitchBranch);
 
 /* -----[ EXCEPTIONS ]----- */
@@ -510,13 +650,22 @@ var AST_Try = DEFNODE("Try", "bcatch bfinally", {
         bcatch: "[AST_Catch?] the catch block, or null if not present",
         bfinally: "[AST_Finally?] the finally block, or null if not present"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            walk_body(this, visitor);
-            if (this.bcatch) this.bcatch._walk(visitor);
-            if (this.bfinally) this.bfinally._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            walk_body(node, visitor);
+            if (node.bcatch) node.bcatch.walk(visitor);
+            if (node.bfinally) node.bfinally.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        if (this.bcatch != null) {
+            if (!(this.bcatch instanceof AST_Catch)) throw new Error("bcatch must be AST_Catch");
+        }
+        if (this.bfinally != null) {
+            if (!(this.bfinally instanceof AST_Finally)) throw new Error("bfinally must be AST_Finally");
+        }
+    },
 }, AST_Block);
 
 var AST_Catch = DEFNODE("Catch", "argname", {
@@ -524,12 +673,16 @@ var AST_Catch = DEFNODE("Catch", "argname", {
     $propdoc: {
         argname: "[AST_SymbolCatch] symbol for the exception"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.argname._walk(visitor);
-            walk_body(this, visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.argname.walk(visitor);
+            walk_body(node, visitor);
         });
-    }
+    },
+    _validate: function() {
+        if (!(this.argname instanceof AST_SymbolCatch)) throw new Error("argname must be AST_SymbolCatch");
+    },
 }, AST_Block);
 
 var AST_Finally = DEFNODE("Finally", null, {
@@ -543,17 +696,23 @@ var AST_Definitions = DEFNODE("Definitions", "definitions", {
     $propdoc: {
         definitions: "[AST_VarDef*] array of variable definitions"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.definitions.forEach(function(defn) {
-                defn._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.definitions.forEach(function(defn) {
+                defn.walk(visitor);
             });
         });
     }
 }, AST_Statement);
 
 var AST_Var = DEFNODE("Var", null, {
-    $documentation: "A `var` statement"
+    $documentation: "A `var` statement",
+    _validate: function() {
+        this.definitions.forEach(function(node) {
+            if (!(node instanceof AST_VarDef)) throw new Error("definitions must be AST_VarDef[]");
+        });
+    },
 }, AST_Definitions);
 
 var AST_VarDef = DEFNODE("VarDef", "name value", {
@@ -562,30 +721,49 @@ var AST_VarDef = DEFNODE("VarDef", "name value", {
         name: "[AST_SymbolVar] name of the variable",
         value: "[AST_Node?] initializer, or null of there's no initializer"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.name._walk(visitor);
-            if (this.value) this.value._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.name.walk(visitor);
+            if (node.value) node.value.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        if (!(this.name instanceof AST_SymbolVar)) throw new Error("name must be AST_SymbolVar");
+        if (this.value != null) must_be_expression(this, "value");
+    },
 });
 
 /* -----[ OTHER ]----- */
 
-var AST_Call = DEFNODE("Call", "expression args", {
+function must_be_expressions(node, prop) {
+    node[prop].forEach(function(node) {
+        if (!(node instanceof AST_Node)) throw new Error(prop + " must be AST_Node[]");
+        if (node instanceof AST_Statement && !(node instanceof AST_Function)) {
+            throw new Error(prop + " cannot contain AST_Statement");
+        }
+    });
+}
+
+var AST_Call = DEFNODE("Call", "expression args pure", {
     $documentation: "A function call expression",
     $propdoc: {
         expression: "[AST_Node] expression to invoke as function",
         args: "[AST_Node*] array of arguments"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.expression._walk(visitor);
-            this.args.forEach(function(node) {
-                node._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.expression.walk(visitor);
+            node.args.forEach(function(arg) {
+                arg.walk(visitor);
             });
         });
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "expression");
+        must_be_expressions(this, "args");
+    },
 });
 
 var AST_New = DEFNODE("New", null, {
@@ -597,13 +775,18 @@ var AST_Sequence = DEFNODE("Sequence", "expressions", {
     $propdoc: {
         expressions: "[AST_Node*] array of expressions (at least two)"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.expressions.forEach(function(node) {
-                node._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.expressions.forEach(function(expr) {
+                expr.walk(visitor);
             });
         });
-    }
+    },
+    _validate: function() {
+        if (this.expressions.length < 2) throw new Error("expressions must contain multiple elements");
+        must_be_expressions(this, "expressions");
+    },
 });
 
 var AST_PropAccess = DEFNODE("PropAccess", "expression property", {
@@ -623,26 +806,37 @@ var AST_PropAccess = DEFNODE("PropAccess", "expression property", {
             return;
         }
         return p;
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "expression");
+    },
 });
 
 var AST_Dot = DEFNODE("Dot", null, {
     $documentation: "A dotted property access expression",
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.expression._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.expression.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        if (typeof this.property != "string") throw new Error("property must be string");
+    },
 }, AST_PropAccess);
 
 var AST_Sub = DEFNODE("Sub", null, {
     $documentation: "Index-style property access, i.e. `a[\"foo\"]`",
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.expression._walk(visitor);
-            this.property._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.expression.walk(visitor);
+            node.property.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "property");
+    },
 }, AST_PropAccess);
 
 var AST_Unary = DEFNODE("Unary", "operator expression", {
@@ -651,11 +845,16 @@ var AST_Unary = DEFNODE("Unary", "operator expression", {
         operator: "[string] the operator",
         expression: "[AST_Node] expression that this unary operator applies to"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.expression._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.expression.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        if (typeof this.operator != "string") throw new Error("operator must be string");
+        must_be_expression(this, "expression");
+    },
 });
 
 var AST_UnaryPrefix = DEFNODE("UnaryPrefix", null, {
@@ -673,12 +872,18 @@ var AST_Binary = DEFNODE("Binary", "operator left right", {
         operator: "[string] the operator",
         right: "[AST_Node] right-hand side expression"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.left._walk(visitor);
-            this.right._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.left.walk(visitor);
+            node.right.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "left");
+        if (typeof this.operator != "string") throw new Error("operator must be string");
+        must_be_expression(this, "right");
+    },
 });
 
 var AST_Conditional = DEFNODE("Conditional", "condition consequent alternative", {
@@ -688,17 +893,26 @@ var AST_Conditional = DEFNODE("Conditional", "condition consequent alternative",
         consequent: "[AST_Node]",
         alternative: "[AST_Node]"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.condition._walk(visitor);
-            this.consequent._walk(visitor);
-            this.alternative._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.condition.walk(visitor);
+            node.consequent.walk(visitor);
+            node.alternative.walk(visitor);
         });
-    }
+    },
+    _validate: function() {
+        must_be_expression(this, "condition");
+        must_be_expression(this, "consequent");
+        must_be_expression(this, "alternative");
+    },
 });
 
 var AST_Assign = DEFNODE("Assign", null, {
     $documentation: "An assignment expression — `a = b + 5`",
+    _validate: function() {
+        if (this.operator.indexOf("=") < 0) throw new Error('operator must contain "="');
+    },
 }, AST_Binary);
 
 /* -----[ LITERALS ]----- */
@@ -708,13 +922,17 @@ var AST_Array = DEFNODE("Array", "elements", {
     $propdoc: {
         elements: "[AST_Node*] array of elements"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.elements.forEach(function(element) {
-                element._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.elements.forEach(function(element) {
+                element.walk(visitor);
             });
         });
-    }
+    },
+    _validate: function() {
+        must_be_expressions(this, "elements");
+    },
 });
 
 var AST_Object = DEFNODE("Object", "properties", {
@@ -722,13 +940,19 @@ var AST_Object = DEFNODE("Object", "properties", {
     $propdoc: {
         properties: "[AST_ObjectProperty*] array of properties"
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.properties.forEach(function(prop) {
-                prop._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.properties.forEach(function(prop) {
+                prop.walk(visitor);
             });
         });
-    }
+    },
+    _validate: function() {
+        this.properties.forEach(function(node) {
+            if (!(node instanceof AST_ObjectProperty)) throw new Error("properties must be AST_ObjectProperty[]");
+        });
+    },
 });
 
 var AST_ObjectProperty = DEFNODE("ObjectProperty", "key value", {
@@ -737,9 +961,10 @@ var AST_ObjectProperty = DEFNODE("ObjectProperty", "key value", {
         key: "[string|AST_SymbolAccessor] property name. For ObjectKeyVal this is a string. For getters and setters this is an AST_SymbolAccessor.",
         value: "[AST_Node] property value.  For getters and setters this is an AST_Accessor."
     },
-    _walk: function(visitor) {
-        return visitor._visit(this, function() {
-            this.value._walk(visitor);
+    walk: function(visitor) {
+        var node = this;
+        visitor.visit(node, function() {
+            node.value.walk(visitor);
         });
     }
 });
@@ -748,15 +973,27 @@ var AST_ObjectKeyVal = DEFNODE("ObjectKeyVal", "quote", {
     $documentation: "A key: value object property",
     $propdoc: {
         quote: "[string] the original quote character"
-    }
+    },
+    _validate: function() {
+        if (typeof this.key != "string") throw new Error("key must be string");
+        must_be_expression(this, "value");
+    },
 }, AST_ObjectProperty);
 
 var AST_ObjectSetter = DEFNODE("ObjectSetter", null, {
     $documentation: "An object setter property",
+    _validate: function() {
+        if (!(this.key instanceof AST_SymbolAccessor)) throw new Error("key must be AST_SymbolAccessor");
+        if (!(this.value instanceof AST_Accessor)) throw new Error("value must be AST_Accessor");
+    },
 }, AST_ObjectProperty);
 
 var AST_ObjectGetter = DEFNODE("ObjectGetter", null, {
     $documentation: "An object getter property",
+    _validate: function() {
+        if (!(this.key instanceof AST_SymbolAccessor)) throw new Error("key must be AST_SymbolAccessor");
+        if (!(this.value instanceof AST_Accessor)) throw new Error("value must be AST_Accessor");
+    },
 }, AST_ObjectProperty);
 
 var AST_Symbol = DEFNODE("Symbol", "scope name thedef", {
@@ -766,6 +1003,9 @@ var AST_Symbol = DEFNODE("Symbol", "scope name thedef", {
         thedef: "[SymbolDef/S] the definition of this symbol"
     },
     $documentation: "Base class for all symbols",
+    _validate: function() {
+        if (typeof this.name != "string") throw new Error("name must be string");
+    },
 });
 
 var AST_SymbolAccessor = DEFNODE("SymbolAccessor", null, {
@@ -817,6 +1057,9 @@ var AST_LabelRef = DEFNODE("LabelRef", null, {
 
 var AST_This = DEFNODE("This", null, {
     $documentation: "The `this` symbol",
+    _validate: function() {
+        if (this.name !== "this") throw new Error('name must be "this"');
+    },
 }, AST_Symbol);
 
 var AST_Constant = DEFNODE("Constant", null, {
@@ -828,21 +1071,30 @@ var AST_String = DEFNODE("String", "value quote", {
     $propdoc: {
         value: "[string] the contents of this string",
         quote: "[string] the original quote character"
-    }
+    },
+    _validate: function() {
+        if (typeof this.value != "string") throw new Error("value must be string");
+    },
 }, AST_Constant);
 
 var AST_Number = DEFNODE("Number", "value", {
     $documentation: "A number literal",
     $propdoc: {
         value: "[number] the numeric value",
-    }
+    },
+    _validate: function() {
+        if (typeof this.value != "number") throw new Error("value must be number");
+    },
 }, AST_Constant);
 
 var AST_RegExp = DEFNODE("RegExp", "value", {
     $documentation: "A regexp literal",
     $propdoc: {
         value: "[RegExp] the actual regexp"
-    }
+    },
+    _validate: function() {
+        if (!(this.value instanceof RegExp)) throw new Error("value must be RegExp");
+    },
 }, AST_Constant);
 
 var AST_Atom = DEFNODE("Atom", null, {
@@ -891,21 +1143,16 @@ var AST_True = DEFNODE("True", null, {
 /* -----[ TreeWalker ]----- */
 
 function TreeWalker(callback) {
-    this.visit = callback;
-    this.stack = [];
+    this.callback = callback;
     this.directives = Object.create(null);
+    this.stack = [];
 }
 TreeWalker.prototype = {
-    _visit: function(node, descend) {
+    visit: function(node, descend) {
         this.push(node);
-        var ret = this.visit(node, descend ? function() {
-            descend.call(node);
-        } : noop);
-        if (!ret && descend) {
-            descend.call(node);
-        }
+        var done = this.callback(node, descend || noop);
+        if (!done && descend) descend();
         this.pop();
-        return ret;
     },
     parent: function(n) {
         return this.stack[this.stack.length - 2 - (n || 0)];

lib/minify.js

@@ -85,9 +85,11 @@ function minify(files, options) {
             sourceMap: false,
             timings: false,
             toplevel: false,
+            validate: false,
             warnings: false,
             wrap: false,
         }, true);
+        if (options.validate) AST_Node.enable_validation();
         var timings = options.timings && {
             start: Date.now()
         };
@@ -129,6 +131,7 @@ function minify(files, options) {
                 content: null,
                 filename: null,
                 includeSources: false,
+                names: true,
                 root: null,
                 url: null,
             }, true);
@@ -138,7 +141,7 @@ function minify(files, options) {
             warnings.push(warning);
         }, options.warnings == "verbose");
         if (timings) timings.parse = Date.now();
-        var source_maps, toplevel;
+        var toplevel;
         if (files instanceof AST_Toplevel) {
             toplevel = files;
         } else {
@@ -151,19 +154,17 @@ function minify(files, options) {
             if (typeof source_map_content == "string" && source_map_content != "inline") {
                 source_map_content = parse_source_map(source_map_content);
             }
-            source_maps = source_map_content && Object.create(null);
+            if (source_map_content) options.sourceMap.orig = Object.create(null);
             for (var name in files) if (HOP(files, name)) {
                 options.parse.filename = name;
                 options.parse.toplevel = toplevel = parse(files[name], options.parse);
-                if (source_maps) {
-                    if (source_map_content == "inline") {
-                        var inlined_content = read_source_map(name, toplevel);
-                        if (inlined_content) {
-                            source_maps[name] = parse_source_map(inlined_content);
-                        }
-                    } else {
-                        source_maps[name] = source_map_content;
+                if (source_map_content == "inline") {
+                    var inlined_content = read_source_map(name, toplevel);
+                    if (inlined_content) {
+                        options.sourceMap.orig[name] = parse_source_map(inlined_content);
                     }
+                } else if (source_map_content) {
+                    options.sourceMap.orig[name] = source_map_content;
                 }
             }
         }
@@ -202,12 +203,7 @@ function minify(files, options) {
         }
         if (!HOP(options.output, "code") || options.output.code) {
             if (options.sourceMap) {
-                options.output.source_map = SourceMap({
-                    content: options.sourceMap.includeSources,
-                    file: options.sourceMap.filename,
-                    orig: source_maps,
-                    root: options.sourceMap.root
-                });
+                options.output.source_map = SourceMap(options.sourceMap);
                 if (options.sourceMap.includeSources) {
                     if (files instanceof AST_Toplevel) {
                         throw new Error("original source content unavailable");
@@ -259,5 +255,7 @@ function minify(files, options) {
         return result;
     } catch (ex) {
         return { error: ex };
+    } finally {
+        AST_Node.disable_validation();
     }
 }

lib/mozilla-ast.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -111,7 +111,7 @@
             var args = {
                 start    : my_start_token(key),
                 end      : my_end_token(M.value),
-                key      : key.type == "Identifier" ? key.name : key.value,
+                key      : "" + key[key.type == "Identifier" ? "name" : "value"],
                 value    : from_moz(M.value)
             };
             if (M.kind == "init") return new AST_ObjectKeyVal(args);
@@ -212,7 +212,14 @@
                             end   : my_end_token(M),
                             name  : M.name
                         });
-        }
+        },
+        ThisExpression: function(M) {
+            return new AST_This({
+                start : my_start_token(M),
+                end   : my_end_token(M),
+                name  : "this",
+            });
+        },
     };
 
     MOZ_TO_ME.UpdateExpression =
@@ -245,7 +252,6 @@
     map("VariableDeclarator", AST_VarDef, "id>name, init>value");
     map("CatchClause", AST_Catch, "param>argname, body%body");
 
-    map("ThisExpression", AST_This);
     map("BinaryExpression", AST_Binary, "operator=operator, left>left, right>right");
     map("LogicalExpression", AST_Binary, "operator=operator, left>left, right>right");
     map("AssignmentExpression", AST_Assign, "operator=operator, left>left, right>right");
@@ -407,6 +413,10 @@
         };
     });
 
+    def_to_moz(AST_This, function To_Moz_ThisExpression() {
+        return { type: "ThisExpression" };
+    });
+
     def_to_moz(AST_RegExp, function To_Moz_RegExpLiteral(M) {
         var flags = M.value.toString().match(/[gimuy]*$/)[0];
         var value = "/" + M.value.raw_source + "/" + flags;

lib/output.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -783,8 +783,8 @@ function OutputStream(options) {
         var p = output.parent();
         if (p instanceof AST_PropAccess && p.expression === this) {
             var value = this.value;
-            // https://github.com/mishoo/UglifyJS2/issues/115
-            // https://github.com/mishoo/UglifyJS2/pull/1009
+            // https://github.com/mishoo/UglifyJS/issues/115
+            // https://github.com/mishoo/UglifyJS/pull/1009
             if (value < 0 || /^0/.test(make_num(value))) {
                 return true;
             }
@@ -1149,7 +1149,7 @@ function OutputStream(options) {
     function parenthesize_for_noin(node, output, noin) {
         var parens = false;
         // need to take some precautions here:
-        //    https://github.com/mishoo/UglifyJS2/issues/60
+        //    https://github.com/mishoo/UglifyJS/issues/60
         if (noin) node.walk(new TreeWalker(function(node) {
             if (parens || node instanceof AST_Scope) return true;
             if (node instanceof AST_Binary && node.operator == "in") {
@@ -1470,7 +1470,6 @@ function OutputStream(options) {
         AST_Node,
         // since the label symbol will mark it
         AST_LabeledStatement,
-        AST_Toplevel,
     ], noop);
 
     // XXX: I'm not exactly sure if we need it for all of these nodes,
@@ -1482,7 +1481,6 @@ function OutputStream(options) {
         AST_Constant,
         AST_Debugger,
         AST_Definitions,
-        AST_Directive,
         AST_Finally,
         AST_Jump,
         AST_Lambda,

lib/parse.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -948,7 +948,7 @@ function parse($TEXT, options) {
         if (!(stat instanceof AST_IterationStatement)) {
             // check for `continue` that refers to this label.
             // those should be reported as syntax errors.
-            // https://github.com/mishoo/UglifyJS2/issues/287
+            // https://github.com/mishoo/UglifyJS/issues/287
             label.references.forEach(function(ref) {
                 if (ref instanceof AST_Continue) {
                     ref = ref.label.start;

lib/propmangle.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 

lib/scope.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -43,23 +43,21 @@
 
 "use strict";
 
-function SymbolDef(scope, orig, init) {
+function SymbolDef(id, scope, orig, init) {
+    this.eliminated = 0;
+    this.global = false;
+    this.id = id;
+    this.init = init;
+    this.lambda = orig instanceof AST_SymbolLambda;
+    this.mangled_name = null;
     this.name = orig.name;
     this.orig = [ orig ];
-    this.init = init;
-    this.eliminated = 0;
-    this.scope = scope;
     this.references = [];
     this.replaced = 0;
-    this.global = false;
-    this.mangled_name = null;
+    this.scope = scope;
     this.undeclared = false;
-    this.id = SymbolDef.next_id++;
-    this.lambda = orig instanceof AST_SymbolLambda;
 }
 
-SymbolDef.next_id = 1;
-
 SymbolDef.prototype = {
     unmangleable: function(options) {
         return this.global && !options.toplevel
@@ -151,6 +149,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
             scope.def_variable(node).defun = defun;
         }
     });
+    self.next_def_id = 0;
     self.walk(tw);
 
     // pass 2: find back references and eval
@@ -240,12 +239,18 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
     }
 });
 
+AST_Scope.DEFMETHOD("make_def", function(orig, init) {
+    var top = this;
+    while (top.parent_scope) top = top.parent_scope;
+    return new SymbolDef(++top.next_def_id, this, orig, init);
+});
+
 AST_Toplevel.DEFMETHOD("def_global", function(node) {
     var globals = this.globals, name = node.name;
     if (globals.has(name)) {
         return globals.get(name);
     } else {
-        var g = new SymbolDef(this, node);
+        var g = this.make_def(node);
         g.undeclared = true;
         g.global = true;
         globals.set(name, g);
@@ -310,7 +315,7 @@ AST_Scope.DEFMETHOD("def_variable", function(symbol, init) {
         def.orig.push(symbol);
         if (def.init instanceof AST_Function) def.init = init;
     } else {
-        def = new SymbolDef(this, symbol, init);
+        def = this.make_def(symbol, init);
         this.variables.set(symbol.name, def);
         def.global = !this.parent_scope;
     }

lib/sourcemap.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -90,14 +90,8 @@ function create_array_map() {
 }
 
 function SourceMap(options) {
-    options = defaults(options, {
-        content: false,
-        file: null,
-        root: null,
-        orig: null,
-    }, true);
     var sources = create_array_map();
-    var sources_content = options.content && Object.create(null);
+    var sources_content = options.includeSources && Object.create(null);
     var names = create_array_map();
     var mappings = "";
     if (options.orig) Object.keys(options.orig).forEach(function(name) {
@@ -119,6 +113,7 @@ function SourceMap(options) {
             if (content) sources_content[map.sources[i]] = content;
         }
     });
+    var prev_source;
     var generated_line = 1;
     var generated_column = 0;
     var source_index = 0;
@@ -137,11 +132,14 @@ function SourceMap(options) {
                     if (orig_col >= col) indices = segments[i];
                     if (orig_col <= col) break;
                 }
-                if (!indices || indices.length < 4) return;
-                source = map.sources[indices[1]];
-                orig_line = indices[2];
-                orig_col = indices[3];
-                if (indices.length > 4) name = map.names[indices[4]];
+                if (!indices || indices.length < 4) {
+                    source = null;
+                } else {
+                    source = map.sources[indices[1]];
+                    orig_line = indices[2];
+                    orig_col = indices[3];
+                    if (indices.length > 4) name = map.names[indices[4]];
+                }
             }
             add(source, gen_line, gen_col, orig_line, orig_col, name);
         } : add,
@@ -151,7 +149,7 @@ function SourceMap(options) {
         toString: function() {
             return JSON.stringify({
                 version: 3,
-                file: options.file || undefined,
+                file: options.filename || undefined,
                 sourceRoot: options.root || undefined,
                 sources: sources,
                 sourcesContent: sources_content ? sources.map(function(source) {
@@ -164,6 +162,8 @@ function SourceMap(options) {
     };
 
     function add(source, gen_line, gen_col, orig_line, orig_col, name) {
+        if (prev_source == null && source == null) return;
+        prev_source = source;
         if (generated_line < gen_line) {
             generated_column = 0;
             do {
@@ -174,6 +174,7 @@ function SourceMap(options) {
         }
         mappings += vlq_encode(gen_col - generated_column);
         generated_column = gen_col;
+        if (source == null) return;
         var src_idx = sources.index(source);
         mappings += vlq_encode(src_idx - source_index);
         source_index = src_idx;
@@ -181,7 +182,7 @@ function SourceMap(options) {
         original_line = orig_line;
         mappings += vlq_encode(orig_col - original_column);
         original_column = orig_col;
-        if (name != null) {
+        if (options.names && name != null) {
             var name_idx = names.index(name);
             mappings += vlq_encode(name_idx - name_index);
             name_index = name_idx;

lib/transform.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 

lib/utils.js

@@ -1,7 +1,7 @@
 /***********************************************************************
 
   A JavaScript tokenizer / parser / beautifier / compressor.
-  https://github.com/mishoo/UglifyJS2
+  https://github.com/mishoo/UglifyJS
 
   -------------------------------- (C) ---------------------------------
 
@@ -87,15 +87,13 @@ DefaultsError.prototype.name = "DefaultsError";
 configure_error_stack(DefaultsError);
 
 function defaults(args, defs, croak) {
-    if (args === true) args = {};
-    var ret = args || {};
-    if (croak) for (var i in ret) if (HOP(ret, i) && !HOP(defs, i)) {
-        throw new DefaultsError("`" + i + "` is not a supported option", defs);
+    if (croak) for (var i in args) {
+        if (HOP(args, i) && !HOP(defs, i)) throw new DefaultsError("`" + i + "` is not a supported option", defs);
     }
-    for (var i in defs) if (HOP(defs, i)) {
-        ret[i] = (args && HOP(args, i)) ? args[i] : defs[i];
+    for (var i in args) {
+        if (HOP(args, i)) defs[i] = args[i];
     }
-    return ret;
+    return defs;
 }
 
 function merge(obj, ext) {
@@ -149,6 +147,9 @@ var List = (function() {
         }
         return top.concat(ret);
     }
+    List.is_op = function(val) {
+        return val === skip || val instanceof AtTop || val instanceof Last || val instanceof Splice;
+    };
     List.at_top = function(val) { return new AtTop(val); };
     List.splice = function(val) { return new Splice(val); };
     List.last = function(val) { return new Last(val); };

package.json

@@ -3,7 +3,7 @@
   "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.9.1",
+  "version": "3.9.3",
   "engines": {
     "node": ">=0.8.0"
   },
@@ -11,7 +11,7 @@
     "Alex Lam <alexlamsl@gmail.com>",
     "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)"
   ],
-  "repository": "mishoo/UglifyJS2",
+  "repository": "mishoo/UglifyJS",
   "main": "tools/node.js",
   "bin": {
     "uglifyjs": "bin/uglifyjs"

test/benchmark.js

@@ -8,9 +8,9 @@ var fetch = require("./fetch");
 var spawn = require("child_process").spawn;
 var zlib = require("zlib");
 var args = process.argv.slice(2);
-args.unshift("bin/uglifyjs");
 if (!args.length) args.push("-mc");
-args.push("--timings");
+args.unshift("bin/uglifyjs");
+args.push("--validate", "--timings");
 var urls = [
     "https://code.jquery.com/jquery-3.4.1.js",
     "https://code.angularjs.org/1.7.8/angular.js",

test/compress.js

@@ -63,7 +63,7 @@ function make_code(ast, options) {
 
 function parse_test(file) {
     var script = fs.readFileSync(file, "utf8");
-    // TODO try/catch can be removed after fixing https://github.com/mishoo/UglifyJS2/issues/348
+    // TODO try/catch can be removed after fixing https://github.com/mishoo/UglifyJS/issues/348
     try {
         var ast = U.parse(script, {
             filename: file
@@ -188,6 +188,7 @@ function reminify(orig_options, input_code, input_formatted, stdout) {
             }
         });
         var options_formatted = JSON.stringify(options, null, 4);
+        options.validate = true;
         var result = U.minify(input_code, options);
         if (result.error) {
             log([
@@ -251,6 +252,7 @@ function run_code(code, toplevel) {
 
 function test_case(test) {
     log("    Running test [{name}]", { name: test.name });
+    U.AST_Node.enable_validation();
     var output_options = test.beautify || {};
     var expect;
     if (test.expect) {

test/compress/asm.js

@@ -91,8 +91,7 @@ asm_mixed: {
         function no_asm_GeometricMean(stdlib, foreign, buffer) {
             function logSum(start, end) {
                 start |= 0, end |= 0;
-                var sum = 0, p = 0, q = 0;
-                for (p = start << 3, q = end << 3; (0 | p) < (0 | q); p = p + 8 | 0) sum += +log(values[p >> 3]);
+                for (var sum = 0, p = 0, q = 0, p = start << 3, q = end << 3; (0 | p) < (0 | q); p = p + 8 | 0) sum += +log(values[p >> 3]);
                 return +sum;
             }
             function geometricMean(start, end) {

test/compress/collapse_vars.js

@@ -803,8 +803,7 @@ collapse_vars_assignment: {
     expect: {
         function log(x) { return console.log(x), x; }
         function f0(c) {
-            var a = 3 / c;
-            return a = a;
+            return 3 / c;
         }
         function f1(c) {
             return 1 - 3 / c;
@@ -2012,6 +2011,7 @@ issue_1631_3: {
         join_vars: true,
         sequences: true,
         side_effects: true,
+        unused: true,
     }
     input: {
         function g() {
@@ -2031,8 +2031,8 @@ issue_1631_3: {
             function f() {
                 return a = 2, 4;
             }
-            var a = 0, b = 1, t = f();
-            return b = a + t;
+            var a = 0, t = f();
+            return a + t;
         }
         console.log(g());
     }
@@ -2204,8 +2204,8 @@ var_defs: {
     }
     expect: {
         var f1 = function(x, y) {
-            var r = x + y, a = r * r - r, b = 7;
-            console.log(a + b);
+            var r = x + y, z = r * r - r, b = 7;
+            console.log(z + b);
         };
         f1("1", 0);
     }
@@ -2569,8 +2569,7 @@ chained_3: {
     }
     expect: {
         console.log(function(a, b) {
-            var c = 1;
-            c = b;
+            var c = 1, c = b;
             b++;
             return c;
         }(0, 2));
@@ -2665,8 +2664,8 @@ double_def_1: {
         a();
     }
     expect: {
-        var a;
-        (a = (a = x) && y)();
+        var a = x;
+        (a = a && y)();
     }
 }
 
@@ -2699,8 +2698,8 @@ toplevel_single_reference: {
     }
     expect: {
         for (var b in x) {
-            var a;
-            b(a = b);
+            var a = b;
+            b(b);
         }
     }
 }
@@ -4243,8 +4242,7 @@ issue_2497: {
             if (true)
                 for (var i = 0; i < 1; ++i)
                     for (var k = 0; k < 1; ++k) {
-                        value = 1;
-                        value = value ? value + 1 : 0;
+                        value = (value = 1) ? value + 1 : 0;
                     }
             else
                 for (i = 0; i < 1; ++i)
@@ -7806,3 +7804,214 @@ issue_3744: {
     }
     expect_stdout: "PASS"
 }
+
+assign_value_def: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            while (1) {
+                var b = a[0], c = a[1];
+                d = b;
+                e = c;
+                if (c[0] - e[0] > c[1] - d[1]) break;
+                return "PASS";
+            }
+            var d, e;
+            return "FAIL";
+        }
+        console.log(f([
+            [ 1, 2 ],
+            [ 3, 4 ],
+        ]));
+    }
+    expect: {
+        function f(a) {
+            while (1) {
+                var b = a[0], c = a[1];
+                if (c[0] - c[0] > c[1] - b[1]) break;
+                return "PASS";
+            }
+            return "FAIL";
+        }
+        console.log(f([
+            [ 1, 2 ],
+            [ 3, 4 ],
+        ]));
+    }
+    expect_stdout: "PASS"
+}
+
+join_vars_value_def: {
+    options = {
+        collapse_vars: true,
+        join_vars: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            while (1) {
+                var b = a[0], c = a[1];
+                d = b;
+                e = c;
+                if (c[0] - e[0] > c[1] - d[1]) break;
+                return "PASS";
+            }
+            var d, e;
+            return "FAIL";
+        }
+        console.log(f([
+            [ 1, 2 ],
+            [ 3, 4 ],
+        ]));
+    }
+    expect: {
+        function f(a) {
+            while (1) {
+                var b = a[0], c = a[1];
+                if (c[0] - c[0] > c[1] - b[1]) break;
+                return "PASS";
+            }
+            return "FAIL";
+        }
+        console.log(f([
+            [ 1, 2 ],
+            [ 3, 4 ],
+        ]));
+    }
+    expect_stdout: "PASS"
+}
+
+var_value_def: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            while (1) {
+                var b = a[0], c = a[1], d = b, e = c;
+                if (c[0] - e[0] > c[1] - d[1]) break;
+                return "PASS";
+            }
+            var d, e;
+            return "FAIL";
+        }
+        console.log(f([
+            [ 1, 2 ],
+            [ 3, 4 ],
+        ]));
+    }
+    expect: {
+        function f(a) {
+            while (1) {
+                var b = a[0], c = a[1];
+                if (c[0] - c[0] > c[1] - b[1]) break;
+                return "PASS";
+            }
+            return "FAIL";
+        }
+        console.log(f([
+            [ 1, 2 ],
+            [ 3, 4 ],
+        ]));
+    }
+    expect_stdout: "PASS"
+}
+
+mangleable_var: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            var b = a(), c = a(), d = b;
+            return c.p(c, d);
+        }
+        console.log(f(function() {
+            return {
+                p: function() {
+                    return "PASS"
+                },
+            };
+        }));
+    }
+    expect: {
+        function f(a) {
+            var b = a(), c = a();
+            return c.p(c, b);
+        }
+        console.log(f(function() {
+            return {
+                p: function() {
+                    return "PASS";
+                }
+            };
+        }));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3884: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 100, b = 1;
+        {
+            a++ + a || a;
+            b <<= a;
+        }
+        console.log(a, b);
+    }
+    expect: {
+        var a = 100;
+        ++a;
+        console.log(a, 32);
+    }
+    expect_stdout: "101 32"
+}
+
+issue_3891: {
+    options = {
+        collapse_vars: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function log(a) {
+            console.log(typeof a);
+        }
+        log(function f() {
+            try {
+                do {
+                    var b = function() {}();
+                } while (f = 0, b.p);
+            } catch (e) {
+                var f;
+                b;
+            }
+        });
+    }
+    expect: {
+        function log(a) {
+            console.log(typeof a);
+        }
+        log(function() {
+            try {
+                do {} while ((void 0).p);
+            } catch (e) {}
+        });
+    }
+    expect_stdout: "function"
+}

test/compress/comparisons.js

@@ -93,6 +93,36 @@ self_comparison_2: {
     expect_stdout: "false true"
 }
 
+self_comparison_3: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        var a;
+        function f() {
+            var b = a;
+            a = null;
+            return b;
+        }
+        for (var i = 0; i < 2; i++)
+            console.log(f() === f());
+    }
+    expect: {
+        var a;
+        function f() {
+            var b = a;
+            a = null;
+            return b;
+        }
+        for (var i = 0; i < 2; i++)
+            console.log(f() === f());
+    }
+    expect_stdout: [
+        "false",
+        "true",
+    ]
+}
+
 issue_2857_1: {
     options = {
         comparisons: true,

test/compress/conditionals.js

@@ -1384,7 +1384,7 @@ hoist_decl: {
     }
     expect: {
         var a, b;
-        x() ? y() : z();
+        (x() ? y : z)();
     }
 }
 
@@ -1666,3 +1666,130 @@ issue_3668: {
     }
     expect_stdout: "undefined"
 }
+
+conditional_assignments_1: {
+    options = {
+        conditionals: true,
+        sequences: true,
+    }
+    input: {
+        function f(a, b, c, d) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+        function g(a, b, c, d) {
+            a = b;
+            if (c); else a = d;
+            return a;
+        }
+        console.log(f(0, "FAIL", 1, "PASS"), g(0, "PASS", 1, "FAIL"));
+    }
+    expect: {
+        function f(a, b, c, d) {
+            return a = c ? d : b, a;
+        }
+        function g(a, b, c, d) {
+            return a = c ? b : d, a;
+        }
+        console.log(f(0, "FAIL", 1, "PASS"), g(0, "PASS", 1, "FAIL"));
+    }
+    expect_stdout: "PASS PASS"
+}
+
+conditional_assignments_2: {
+    options = {
+        conditionals: true,
+        sequences: true,
+    }
+    input: {
+        function f1(b, c, d) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+        function f2(a, c, d) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+        function f3(a, b, d) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+        function f4(a, b, c) {
+            a = b;
+            if (c) a = d;
+            return a;
+        }
+    }
+    expect: {
+        function f1(b, c, d) {
+            return a = c ? d : b, a;
+        }
+        function f2(a, c, d) {
+            return a = b, c && (a = d), a;
+        }
+        function f3(a, b, d) {
+            return a = b, c && (a = d), a;
+        }
+        function f4(a, b, c) {
+            return a = b, c && (a = d), a;
+        }
+    }
+}
+
+conditional_assignments_3: {
+    options = {
+        conditionals: true,
+        sequences: true,
+    }
+    input: {
+        console.log(function(a, b) {
+            a = "PASS";
+            if (b) a = a;
+            return a;
+        }(0, 1));
+    }
+    expect: {
+        console.log(function(a, b) {
+            return a = "PASS", b && (a = a), a;
+        }(0, 1));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3808_1: {
+    options = {
+        conditionals: true,
+        side_effects: true,
+    }
+    input: {
+        var a;
+        a = "PASS", [] + "" && (a = "FAIL");
+        console.log(a);
+    }
+    expect: {
+        var a;
+        a = [] + "" ? "FAIL" : "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3808_2: {
+    options = {
+        conditionals: true,
+        side_effects: true,
+    }
+    input: {
+        var a;
+        console.log((a = "PASS", [] + "" && (a = "FAIL")), a);
+    }
+    expect: {
+        var a;
+        console.log((a = "PASS", [] + "" && (a = "FAIL")), a);
+    }
+    expect_stdout: " PASS"
+}

test/compress/dead-code.js

@@ -97,6 +97,66 @@ dead_code_constant_boolean_should_warn_more: {
     node_version: "<=4"
 }
 
+trim_try: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        try {
+            var a;
+        } catch (e) {
+            console.log("FAIL");
+        } finally {
+            console.log(a);
+        }
+    }
+    expect: {
+        var a;
+        console.log(a);
+    }
+    expect_stdout: "undefined"
+}
+
+trim_finally_1: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        try {
+            console.log("PASS");
+        } finally {
+            var a;
+        }
+    }
+    expect: {
+        console.log("PASS");
+        var a;
+    }
+    expect_stdout: "PASS"
+}
+
+trim_finally_2: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        try {
+            console.log("PASS");
+        } catch (e) {
+        } finally {
+            var a;
+        }
+    }
+    expect: {
+        try {
+            console.log("PASS");
+            var a;
+        } catch (e) {
+        }
+    }
+    expect_stdout: "PASS"
+}
+
 try_catch_finally: {
     options = {
         conditionals: true,
@@ -130,10 +190,7 @@ try_catch_finally: {
             a = 3;
             console.log("PASS");
         }();
-        try {
-            console.log(a);
-        } finally {
-        }
+        console.log(a);
     }
     expect_stdout: [
         "PASS",
@@ -892,3 +949,222 @@ issue_3578: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3830_1: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        var o = {
+            set p(v) {
+                o = o.p = o = v;
+            }
+        };
+        o.p = "PASS";
+        console.log(o);
+    }
+    expect: {
+        var o = {
+            set p(v) {
+                o = o.p = o = v;
+            }
+        };
+        o.p = "PASS";
+        console.log(o);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_2: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = o[a] = a = v;
+            }
+        };
+        o[a] = "PASS";
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = o[a] = a = v;
+            }
+        };
+        o[a] = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_3: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        function f() {
+            return a;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = o[f()] = a = v;
+            }
+        };
+        o[f()] = "PASS";
+        console.log(a);
+    }
+    expect: {
+        function f() {
+            return a;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = o[f()] = a = v;
+            }
+        };
+        o[f()] = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_4: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        function f() {
+            return o;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = f()[a] = a = v;
+            }
+        };
+        f()[a] = "PASS";
+        console.log(a);
+    }
+    expect: {
+        function f() {
+            return o;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = f()[a] = a = v;
+            }
+        };
+        f()[a] = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_5: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        function f() {
+            return o;
+        }
+        function g() {
+            return a;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = f()[g()] = a = v;
+            }
+        };
+        f()[g()] = "PASS";
+        console.log(a);
+    }
+    expect: {
+        function f() {
+            return o;
+        }
+        function g() {
+            return a;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                a = f()[g()] = a = v;
+            }
+        };
+        f()[g()] = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3830_6: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        function f() {
+            return o;
+        }
+        function g() {
+            return a;
+        }
+        function h(v) {
+            a = f()[g()] = a = v;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                h(v);
+            }
+        };
+        o.FAIL = "PASS";
+        console.log(a);
+    }
+    expect: {
+        function f() {
+            return o;
+        }
+        function g() {
+            return a;
+        }
+        function h(v) {
+            a = f()[g()] = a = v;
+        }
+        var a = "FAIL";
+        var o = {
+            set FAIL(v) {
+                h(v);
+            }
+        };
+        o.FAIL = "PASS";
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+redundant_assignments: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        var a = a = "PASS", b = "FAIL";
+        b = b = "PASS";
+        console.log(a, b);
+    }
+    expect: {
+        var a = "PASS", b = "FAIL";
+        b = "PASS";
+        console.log(a, b);
+    }
+    expect_stdout: "PASS PASS"
+}

test/compress/directives.js

@@ -46,7 +46,7 @@ simple_statement_is_not_a_directive: {
 drop_lone_use_strict: {
     options = {
         directives: true,
-        side_effects: true,
+        unused: true,
     }
     input: {
         function f1() {
@@ -66,10 +66,8 @@ drop_lone_use_strict: {
         function f1() {
         }
         function f2() {
-            "use strict";
-            function f3() {
-            }
         }
+        (function() {})();
     }
 }
 

test/compress/drop-unused.js

@@ -2366,7 +2366,7 @@ function_parameter_ie8: {
     }
     expect: {
         (function() {
-            (function f() {
+            (function() {
                 console.log("PASS");
             })();
         })();
@@ -2444,3 +2444,91 @@ issue_3746: {
     }
     expect_stdout: "PASS"
 }
+
+drop_duplicated_side_effects: {
+    options = {
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        for (var i = 1; i--;)
+            var a = 0, b = ++a;
+        console.log(a);
+    }
+    expect: {
+        var a = 0;
+        for (var i = 1; i--;)
+            a = 0, ++a;
+        console.log(a);
+    }
+    expect_stdout: "1"
+}
+
+drop_duplicated_var_catch: {
+    options = {
+        unused: true,
+    }
+    input: {
+        function f() {
+            try {
+                x();
+            } catch (a) {
+                var a, a;
+            }
+        }
+    }
+    expect: {
+        function f() {
+            try {
+                x();
+            } catch (a) {
+                var a;
+            }
+        }
+    }
+}
+
+issue_3802_1: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        a += 0;
+        var a = function() {};
+        console.log(typeof a);
+    }
+    expect: {
+        var a = 0;
+        a += 0;
+        a = function() {};
+        console.log(typeof a);
+    }
+    expect_stdout: "function"
+}
+
+issue_3802_2: {
+    options = {
+        functions: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        a += 0;
+        var a = function() {};
+        console.log(typeof a);
+    }
+    expect: {
+        0;
+        function a() {};
+        console.log(typeof a);
+    }
+    expect_stdout: "function"
+}

test/compress/evaluate.js

@@ -2190,3 +2190,231 @@ issue_3755: {
     }
     expect_stdout: "undefined"
 }
+
+void_side_effects: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = void console.log("PASS");
+        console.log(a);
+    }
+    expect: {
+        console.log("PASS");
+        console.log(void 0);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+no_returns: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = function() {
+            console.log("PASS");
+        }();
+        console.log(a);
+    }
+    expect: {
+        (function() {
+            console.log("PASS");
+        })();
+        console.log(void 0);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+void_returns: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = function f() {
+            function g(b) {
+                if (b) console.log("FAIL");
+            }
+            while (1) {
+                console.log("PASS");
+                try {
+                    if (console) return;
+                } catch (e) {
+                    return g(e);
+                }
+            }
+        }();
+        console.log(a);
+    }
+    expect: {
+        (function() {
+            function g(b) {
+                if (b) console.log("FAIL");
+            }
+            while (1) {
+                console.log("PASS");
+                try {
+                    if (console) return;
+                } catch (e) {
+                    return g(e);
+                }
+            }
+        })();
+        console.log(void 0);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+void_returns_recursive: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = function f() {
+            function g(b) {
+                return f();
+            }
+            while (1) {
+                console.log("PASS");
+                try {
+                    if (console) return;
+                } catch (e) {
+                    return g(e);
+                }
+            }
+        }();
+        console.log(a);
+    }
+    expect: {
+        var a = function f() {
+            function g(b) {
+                return f();
+            }
+            while (1) {
+                console.log("PASS");
+                try {
+                    if (console) return;
+                } catch (e) {
+                    return g();
+                }
+            }
+        }();
+        console.log(a);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+issue_3878_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var b = function(a) {
+            return (a = 0) == (a && this > (a += 0));
+        }();
+        console.log(b ? "PASS" : "FAIL");
+    }
+    expect: {
+        var b = function(a) {
+            return (a = 0) == (a && this > (a += 0));
+        }();
+        console.log(b ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3878_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "foo";
+        a++ + a;
+        a && a;
+        console.log(a);
+    }
+    expect: {
+        var a = "foo";
+        a++ + a;
+        a;
+        console.log(a);
+    }
+    expect_stdout: "NaN"
+}
+
+issue_3882: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            return console.log(a++), a && this;
+        }
+        var b = f();
+        console.log(b);
+    }
+    expect: {
+        var b = function(a) {
+            return console.log(a++), a && this;
+        }();
+        console.log(b);
+    }
+    expect_stdout: [
+        "NaN",
+        "NaN",
+    ]
+}
+
+issue_3887: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(b) {
+            try {
+                b-- && console.log("PASS");
+            } catch (a_2) {}
+        })(1);
+    }
+    expect: {
+        (function(b) {
+            try {
+                b-- && console.log("PASS");
+            } catch (a_2) {}
+        })(1);
+    }
+    expect_stdout: "PASS"
+}

test/compress/functions.js

@@ -2877,7 +2877,7 @@ issue_2437: {
     }
 }
 
-issue_2485: {
+issue_2485_1: {
     options = {
         functions: true,
         reduce_funcs: true,
@@ -2926,6 +2926,54 @@ issue_2485: {
     expect_stdout: "6"
 }
 
+issue_2485_2: {
+    options = {
+        functions: true,
+        inline: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        var foo = function(bar) {
+            var n = function(a, b) {
+                return a + b;
+            };
+            var sumAll = function(arg) {
+                return arg.reduce(n, 0);
+            };
+            var runSumAll = function(arg) {
+                return sumAll(arg);
+            };
+            bar.baz = function(arg) {
+                var n = runSumAll(arg);
+                return (n.get = 1), n;
+            };
+            return bar;
+        };
+        var bar = foo({});
+        console.log(bar.baz([1, 2, 3]));
+    }
+    expect: {
+        var foo = function(bar) {
+            function n(a, b) {
+                return a + b;
+            }
+            function runSumAll(arg) {
+                return arg.reduce(n, 0);
+            }
+            bar.baz = function(arg) {
+                var n = runSumAll(arg);
+                return (n.get = 1), n;
+            };
+            return bar;
+        };
+        var bar = foo({});
+        console.log(bar.baz([1, 2, 3]));
+    }
+    expect_stdout: "6"
+}
+
 issue_3364: {
     options = {
         functions: true,
@@ -3113,9 +3161,7 @@ issue_3400_1: {
                 return console.log(o[g]), o;
             }
             function e() {
-                return [ 42 ].map(function(v) {
-                    return h(v);
-                });
+                return [ 42 ].map(h);
             }
             return e();
         }()[0].p);
@@ -3130,7 +3176,7 @@ issue_3400_2: {
     options = {
         collapse_vars: true,
         inline: true,
-        passes: 2,
+        passes: 3,
         reduce_funcs: true,
         reduce_vars: true,
         unused: true,
@@ -3158,11 +3204,11 @@ issue_3400_2: {
     }
     expect: {
         void console.log(function g() {
-            return [ 42 ].map(function(v) {
-                return o = {
-                    p: v
-                }, console.log(o[g]), o;
-                var o;
+            return [ 42 ].map(function(u) {
+                var o = {
+                    p: u
+                };
+                return console.log(o[g]), o;
             });
         }()[0].p);
     }
@@ -3468,10 +3514,9 @@ hoisted_single_use: {
     }
     expect: {
         function f(a) {
-            for (var r in a) g(r);
-        }
-        function g(a) {
-            console.log(a);
+            for (var r in a) (function(a) {
+                console.log(a);
+            })(r);
         }
         (function(a) {
             var g = a.bar;
@@ -3568,8 +3613,8 @@ pr_3592_2: {
         var g = [ "PASS" ];
         console.log((z = "PASS", function(problem) {
             return g[problem];
-        }((y = z, problem(y)))));
-        var z, y;
+        }(problem(z))));
+        var z;
     }
     expect_stdout: "PASS"
 }
@@ -3635,9 +3680,7 @@ pr_3595_1: {
         }
         console.log((arg = "PASS", function(problem) {
             return g[problem];
-        }(function(arg) {
-            return problem(arg);
-        }(arg))));
+        }(problem(arg))));
         var arg;
     }
     expect_stdout: "PASS"
@@ -3678,9 +3721,7 @@ pr_3595_2: {
         }
         console.log(function(problem) {
             return g[problem];
-        }(function(arg) {
-            return problem(arg);
-        }("PASS")));
+        }(problem("PASS")));
     }
     expect_stdout: "PASS"
 }
@@ -4062,3 +4103,580 @@ issue_3777_2: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3821_1: {
+    options = {
+        inline: true,
+    }
+    input: {
+        var a = 0;
+        console.log(function(b) {
+            return +a + b;
+        }(--a));
+    }
+    expect: {
+        var a = 0;
+        console.log(function(b) {
+            return +a + b;
+        }(--a));
+    }
+    expect_stdout: "-2"
+}
+
+issue_3821_2: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "PASS";
+        function f(g, b) {
+            return g(), b;
+        }
+        console.log(f(function() {
+            a = "FAIL";
+        }, a));
+    }
+    expect: {
+        var a = "PASS";
+        function f(g, b) {
+            return g(), b;
+        }
+        console.log(f(function() {
+            a = "FAIL";
+        }, a));
+    }
+    expect_stdout: "PASS"
+}
+
+substitute: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var o = {};
+        function f(a) {
+            return a === o ? "PASS" : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return function(b) {
+                    return f(b);
+                };
+            },
+            function() {
+                "use strict";
+                return function(c) {
+                    return f(c);
+                };
+            },
+            function() {
+                return function(c) {
+                    "use strict";
+                    return f(c);
+                };
+            },
+            function() {
+                return function(d, e) {
+                    return f(d, e);
+                };
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o), g().length);
+        });
+    }
+    expect: {
+        var o = {};
+        function f(a) {
+            return a === o ? "PASS" : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return f;
+            },
+            function() {
+                "use strict";
+                return f;
+            },
+            function() {
+                return f;
+            },
+            function() {
+                return function(d, e) {
+                    return f(d, e);
+                };
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o), g().length);
+        });
+    }
+    expect_stdout: [
+        "PASS PASS 1",
+        "PASS PASS 1",
+        "PASS PASS 1",
+        "PASS PASS 1",
+        "PASS PASS 2",
+    ]
+}
+
+substitute_add_farg: {
+    options = {
+        inline: true,
+        keep_fargs: "strict",
+    }
+    input: {
+        function f(g) {
+            console.log(g.length);
+            g(null, "FAIL");
+        }
+        f(function() {
+            return function(a, b) {
+                return function(c) {
+                    do {
+                        console.log("PASS");
+                    } while (c);
+                }(a, b);
+            };
+        }());
+    }
+    expect: {
+        function f(g) {
+            console.log(g.length);
+            g(null, "FAIL");
+        }
+        f(function(c, argument_1) {
+            do {
+                console.log("PASS");
+            } while (c);
+        });
+    }
+    expect_stdout: [
+        "2",
+        "PASS",
+    ]
+}
+
+substitute_arguments: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var o = {};
+        function f(a) {
+            return arguments[0] === o ? "PASS" : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return function(b) {
+                    return f(b);
+                };
+            },
+            function() {
+                "use strict";
+                return function(c) {
+                    return f(c);
+                };
+            },
+            function() {
+                return function(c) {
+                    "use strict";
+                    return f(c);
+                };
+            },
+            function() {
+                return function(d, e) {
+                    return f(d, e);
+                };
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o), g().length);
+        });
+    }
+    expect: {
+        var o = {};
+        function f(a) {
+            return arguments[0] === o ? "PASS" : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return function(b) {
+                    return f(b);
+                };
+            },
+            function() {
+                "use strict";
+                return function(c) {
+                    return f(c);
+                };
+            },
+            function() {
+                return function(c) {
+                    "use strict";
+                    return f(c);
+                };
+            },
+            function() {
+                return function(d, e) {
+                    return f(d, e);
+                };
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o), g().length);
+        });
+    }
+    expect_stdout: [
+        "PASS PASS 1",
+        "PASS PASS 1",
+        "PASS PASS 1",
+        "PASS PASS 1",
+        "PASS PASS 2",
+    ]
+}
+
+substitute_drop_farg: {
+    options = {
+        inline: true,
+        keep_fargs: false,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var o = {};
+        function f(a) {
+            return a === o ? "PASS" : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return function(b) {
+                    return f(b);
+                };
+            },
+            function() {
+                "use strict";
+                return function(c) {
+                    return f(c);
+                };
+            },
+            function() {
+                return function(c) {
+                    "use strict";
+                    return f(c);
+                };
+            },
+            function() {
+                return function(d, e) {
+                    return f(d, e);
+                };
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o));
+        });
+    }
+    expect: {
+        var o = {};
+        function f(a) {
+            return a === o ? "PASS" : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return f;
+            },
+            function() {
+                "use strict";
+                return f;
+            },
+            function() {
+                return f;
+            },
+            function() {
+                return f;
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o));
+        });
+    }
+    expect_stdout: [
+        "PASS PASS",
+        "PASS PASS",
+        "PASS PASS",
+        "PASS PASS",
+        "PASS PASS",
+    ]
+}
+
+substitute_this: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var o = {};
+        function f(a) {
+            return a === o ? this === o : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return function(b) {
+                    return f(b);
+                };
+            },
+            function() {
+                "use strict";
+                return function(c) {
+                    return f(c);
+                };
+            },
+            function() {
+                return function(c) {
+                    "use strict";
+                    return f(c);
+                };
+            },
+            function() {
+                return function(d, e) {
+                    return f(d, e);
+                };
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o), g().length);
+        });
+    }
+    expect: {
+        var o = {};
+        function f(a) {
+            return a === o ? this === o : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return function(b) {
+                    return f(b);
+                };
+            },
+            function() {
+                "use strict";
+                return function(c) {
+                    return f(c);
+                };
+            },
+            function() {
+                return function(c) {
+                    "use strict";
+                    return f(c);
+                };
+            },
+            function() {
+                return function(d, e) {
+                    return f(d, e);
+                };
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o), g().length);
+        });
+    }
+    expect_stdout: [
+        "false true 1",
+        "false false 1",
+        "false false 1",
+        "false false 1",
+        "false false 2",
+    ]
+}
+
+substitute_use_strict: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var o = {};
+        function f(a) {
+            "use strict";
+            return a === o ? "PASS" : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return function(b) {
+                    return f(b);
+                };
+            },
+            function() {
+                "use strict";
+                return function(c) {
+                    return f(c);
+                };
+            },
+            function() {
+                return function(c) {
+                    "use strict";
+                    return f(c);
+                };
+            },
+            function() {
+                return function(d, e) {
+                    return f(d, e);
+                };
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o), g().length);
+        });
+    }
+    expect: {
+        var o = {};
+        function f(a) {
+            "use strict";
+            return a === o ? "PASS" : "FAIL";
+        }
+        [
+            function() {
+                return f;
+            },
+            function() {
+                return f;
+            },
+            function() {
+                "use strict";
+                return f;
+            },
+            function() {
+                return f;
+            },
+            function() {
+                return function(d, e) {
+                    return f(d, e);
+                };
+            },
+        ].forEach(function(g) {
+            console.log(g()(o), g().call(o, o), g().length);
+        });
+    }
+    expect_stdout: [
+        "PASS PASS 1",
+        "PASS PASS 1",
+        "PASS PASS 1",
+        "PASS PASS 1",
+        "PASS PASS 2",
+    ]
+}
+
+issue_3833: {
+    options = {
+        inline: true,
+        keep_fargs: "strict",
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f(a) {
+            return function() {
+                while (a);
+                console.log("PASS");
+            }();
+        }
+        f();
+    }
+    expect: {
+        (function() {
+            while (a);
+            console.log("PASS");
+        })();
+        var a;
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3835: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+    }
+    input: {
+        (function f() {
+            return function() {
+                return f();
+            }();
+        })();
+    }
+    expect: {
+        (function f() {
+            return f();
+        })();
+    }
+    expect_stdout: true
+}
+
+issue_3836: {
+    options = {
+        inline: true,
+    }
+    input: {
+        (function() {
+            return function() {
+                for (var a in 0)
+                    console.log(k);
+            }(console.log("PASS"));
+        })();
+    }
+    expect: {
+        (function() {
+            for (var a in 0)
+                console.log(k);
+        })(console.log("PASS"));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3852: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            return function(b) {
+                return b && (b[0] = 0), "PASS";
+            }(a);
+        }(42));
+    }
+    expect: {
+        console.log(function(a) {
+            return a && (a[0] = 0), "PASS";
+        }(42));
+    }
+    expect_stdout: "PASS"
+}

test/compress/hoist_props.js

@@ -767,18 +767,17 @@ issue_3071_1: {
             var obj = {};
             obj.one = 1;
             obj.two = 2;
-            console.log(obj.one);
+            console.log(obj.one, obj.two);
         })();
     }
     expect: {
-        console.log(1);
+        console.log(1, 2);
     }
-    expect_stdout: "1"
+    expect_stdout: "1 2"
 }
 
 issue_3071_2: {
     options = {
-        evaluate: true,
         hoist_props: true,
         inline: true,
         join_vars: true,
@@ -793,19 +792,18 @@ issue_3071_2: {
             obj = {};
             obj.one = 1;
             obj.two = 2;
-            console.log(obj.one);
+            console.log(obj.one, obj.two);
             var obj;
         })();
     }
     expect: {
-        console.log(1);
+        console.log(1, 2);
     }
-    expect_stdout: "1"
+    expect_stdout: "1 2"
 }
 
 issue_3071_2_toplevel: {
     options = {
-        evaluate: true,
         hoist_props: true,
         inline: true,
         join_vars: true,
@@ -821,14 +819,14 @@ issue_3071_2_toplevel: {
             obj = {};
             obj.one = 1;
             obj.two = 2;
-            console.log(obj.one);
+            console.log(obj.one, obj.two);
             var obj;
         })();
     }
     expect: {
-        console.log(1);
+        console.log(1, 2);
     }
-    expect_stdout: "1"
+    expect_stdout: "1 2"
 }
 
 issue_3071_3: {
@@ -914,3 +912,63 @@ issue_3440: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3868: {
+    options = {
+        hoist_props: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+    }
+    input: {
+        (function(t) {
+            t = {};
+            ({
+                get p() {},
+                q: (console.log("PASS"), +t),
+            }).r;
+        })();
+    }
+    expect: {
+        (function(t) {
+            t = {};
+            ({
+                get p() {},
+                q: (console.log("PASS"), +t),
+            }).r;
+        })();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3871: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function() {
+            do {
+                var b = {
+                    get null() {
+                        c;
+                    }
+                };
+            } while (!b);
+            return "PASS";
+        }());
+    }
+    expect: {
+        console.log(function() {
+            do {
+                var b = {
+                    get null() {
+                        c;
+                    }
+                };
+            } while (!b);
+            return "PASS";
+        }());
+    }
+    expect_stdout: "PASS"
+}

test/compress/ie8.js

@@ -2389,7 +2389,7 @@ issue_3703: {
         var a = "PASS";
         (function() {
             var b;
-            var c = function g() {
+            var c = function() {
                 a = "FAIL";
             };
             a ? b |= c : b.p;
@@ -2420,3 +2420,72 @@ issue_3750: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3823: {
+    options = {
+        ie8: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        for (var i = 0; i < 1; i++) {
+            var a = a ? function f() {
+                f;
+            } : 0;
+            console.log("PASS", typeof f);
+        }
+    }
+    expect: {
+        for (var i = 0; i < 1; i++) {
+            (function f() {
+                f;
+            });
+            console.log("PASS", typeof f);
+        }
+    }
+    expect_stdout: "PASS undefined"
+}
+
+issue_3825: {
+    options = {
+        ie8: true,
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        console.log({}[void (0..length ? 1 : 2)]);
+    }
+    expect: {
+        console.log({}[void 0]);
+    }
+    expect_stdout: "undefined"
+}
+
+issue_3889: {
+    options = {
+        evaluate: true,
+        ie8: true,
+        reduce_vars: true,
+    }
+    input: {
+        function f(a) {
+            a = 0;
+            (function a() {
+                var a;
+                console.log(a);
+            })();
+        }
+        f();
+    }
+    expect: {
+        function f(a) {
+            a = 0;
+            (function a() {
+                var a;
+                console.log(a);
+            })();
+        }
+        f();
+    }
+    expect_stdout: "undefined"
+}

test/compress/if_return.js

@@ -573,3 +573,24 @@ issue_3600: {
     }
     expect_stdout: "1"
 }
+
+iife_if_return_simple: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        inline: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        (function() {
+            if (console)
+                return console.log("PASS");
+            console.log("FAIL");
+        })();
+    }
+    expect: {
+        console ? console.log("PASS") : console.log("FAIL");
+    }
+    expect_stdout: "PASS"
+}

test/compress/issue-1034.js

@@ -90,13 +90,13 @@ non_hoisted_function_after_return_2a: {
         "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:7,16]",
         "WARN: Dropping unused variable a [test/compress/issue-1034.js:4,20]",
         "WARN: Dropping unused function nope [test/compress/issue-1034.js:11,21]",
-        "INFO: pass 0: last_count: Infinity, count: 37",
+        "INFO: pass 0: last_count: Infinity, count: 36",
         "WARN: Dropping unreachable code [test/compress/issue-1034.js:9,12]",
         "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:9,12]",
         "WARN: Dropping unreachable code [test/compress/issue-1034.js:12,12]",
         "INFO: Dropping unused variable b [test/compress/issue-1034.js:7,20]",
         "INFO: Dropping unused variable c [test/compress/issue-1034.js:9,16]",
-        "INFO: pass 1: last_count: 37, count: 18",
+        "INFO: pass 1: last_count: 36, count: 18",
     ]
 }
 
@@ -248,13 +248,13 @@ non_hoisted_function_after_return_2a_strict: {
         "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:8,16]",
         "WARN: Dropping unused variable a [test/compress/issue-1034.js:5,20]",
         "WARN: Dropping unused function nope [test/compress/issue-1034.js:12,21]",
-        "INFO: pass 0: last_count: Infinity, count: 48",
+        "INFO: pass 0: last_count: Infinity, count: 47",
         "WARN: Dropping unreachable code [test/compress/issue-1034.js:10,12]",
         "WARN: Declarations in unreachable code! [test/compress/issue-1034.js:10,12]",
         "WARN: Dropping unreachable code [test/compress/issue-1034.js:13,12]",
         "INFO: Dropping unused variable b [test/compress/issue-1034.js:8,20]",
         "INFO: Dropping unused variable c [test/compress/issue-1034.js:10,16]",
-        "INFO: pass 1: last_count: 48, count: 29",
+        "INFO: pass 1: last_count: 47, count: 29",
     ]
 }
 

test/compress/issue-1639.js

@@ -22,8 +22,9 @@ issue_1639_1: {
         console.log(a, b);
     }
     expect: {
-        for (var a = 100, b = 10, L1 = 5; --L1 > 0;)
-            if (--b, 0) var ignore = 0;
+        for (var a = 100, b = 10, L1 = 5, ignore; --L1 > 0;) {
+            --b;
+        }
         console.log(a, b);
     }
     expect_stdout: "100 6"

test/compress/issue-1656.js

@@ -35,11 +35,7 @@ f7: {
         console.log(a, b);
     }
     expect_exact: [
-        "var b = 10;",
-        "",
-        "!function() {",
-        "    b = 100;",
-        "}(), console.log(100, b);",
+        "console.log(100, 100);",
     ]
-    expect_stdout: true
+    expect_stdout: "100 100"
 }

test/compress/keep_fargs.js

@@ -1226,8 +1226,7 @@ chained_3: {
     }
     expect: {
         console.log(function(b) {
-            var c = 1;
-            c = b;
+            var c = 1, c = b;
             b++;
             return c;
         }(2));

test/compress/labels.js

@@ -3,6 +3,7 @@ labels_1: {
         conditionals: true,
         dead_code: true,
         if_return: true,
+        unused: true,
     }
     input: {
         out: {
@@ -21,6 +22,7 @@ labels_2: {
         conditionals: true,
         dead_code: true,
         if_return: true,
+        unused: true,
     }
     input: {
         out: {
@@ -61,6 +63,7 @@ labels_4: {
         conditionals: true,
         dead_code: true,
         if_return: true,
+        unused: true,
     }
     input: {
         out: for (var i = 0; i < 5; ++i) {
@@ -105,6 +108,9 @@ labels_5: {
 }
 
 labels_6: {
+    options = {
+        dead_code: true,
+    }
     input: {
         out: break out;
     };
@@ -159,6 +165,7 @@ labels_9: {
         conditionals: true,
         dead_code: true,
         if_return: true,
+        unused: true,
     }
     input: {
         out: while (foo) {

test/compress/loops.js

@@ -549,6 +549,7 @@ issue_2740_2: {
         dead_code: true,
         loops: true,
         passes: 2,
+        unused: true,
     }
     input: {
         L1: while (x()) {
@@ -564,6 +565,7 @@ issue_2740_3: {
     options = {
         dead_code: true,
         loops: true,
+        unused: true,
     }
     input: {
         L1: for (var x = 0; x < 3; x++) {
@@ -589,6 +591,7 @@ issue_2740_4: {
         dead_code: true,
         loops: true,
         passes: 2,
+        unused: true,
     }
     input: {
         L1: for (var x = 0; x < 3; x++) {
@@ -613,6 +616,7 @@ issue_2740_5: {
         dead_code: true,
         loops: true,
         passes: 2,
+        unused: true,
     }
     input: {
         L1: for (var x = 0; x < 3; x++) {
@@ -763,6 +767,7 @@ issue_3631_1: {
         loops: true,
         reduce_vars: true,
         toplevel: true,
+        unused: true,
     }
     input: {
         var c = 0;
@@ -789,6 +794,7 @@ issue_3631_2: {
         loops: true,
         reduce_vars: true,
         toplevel: true,
+        unused: true,
     }
     input: {
         L: for (var a = 1; a--; console.log(b)) {

test/compress/properties.js

@@ -1143,558 +1143,6 @@ const_prop_assign_pure: {
     }
 }
 
-join_object_assignments_1: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var x = {
-                a: 1,
-                c: (console.log("c"), "C"),
-            };
-            x.b = 2;
-            x[3] = function() {
-                console.log(x);
-            },
-            x["a"] = /foo/,
-            x.bar = x;
-            return x;
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var x = {
-                a: 1,
-                c: (console.log("c"), "C"),
-                b: 2,
-                3: function() {
-                    console.log(x);
-                },
-                a: /foo/,
-            };
-            x.bar = x;
-            return x;
-        }());
-    }
-    expect_stdout: true
-}
-
-join_object_assignments_2: {
-    options = {
-        evaluate: true,
-        hoist_props: true,
-        join_vars: true,
-        passes: 3,
-        reduce_vars: true,
-        toplevel: true,
-        unused: true,
-    }
-    input: {
-        var o = {
-            foo: 1,
-        };
-        o.bar = 2;
-        o.baz = 3;
-        console.log(o.foo, o.bar + o.bar, o.foo * o.bar * o.baz);
-    }
-    expect: {
-        console.log(1, 4, 6);
-    }
-    expect_stdout: "1 4 6"
-}
-
-join_object_assignments_3: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                a: "PASS",
-            }, a = o.a;
-            o.a = "FAIL";
-            return a;
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var o = {
-                a: "PASS",
-            }, a = o.a;
-            o.a = "FAIL";
-            return a;
-        }());
-    }
-    expect_stdout: "PASS"
-}
-
-join_object_assignments_4: {
-    options = {
-        join_vars: true,
-        sequences: true,
-    }
-    input: {
-        var o;
-        console.log(o);
-        o = {};
-        o.a = "foo";
-        console.log(o.b);
-        o.b = "bar";
-        console.log(o.a);
-    }
-    expect: {
-        var o;
-        console.log(o),
-        o = {
-            a: "foo",
-        },
-        console.log(o.b),
-        o.b = "bar",
-        console.log(o.a);
-    }
-    expect_stdout: [
-        "undefined",
-        "undefined",
-        "foo",
-    ]
-}
-
-join_object_assignments_return_1: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                p: 3
-            };
-            return o.q = "foo";
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var o = {
-                p: 3,
-                q: "foo"
-            };
-            return o.q;
-        }());
-    }
-    expect_stdout: "foo"
-}
-
-join_object_assignments_return_2: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                p: 3
-            };
-            return o.q = /foo/,
-            o.r = "bar";
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var o = {
-                p: 3,
-                q: /foo/,
-                r: "bar"
-            };
-            return o.r;
-        }());
-    }
-    expect_stdout: "bar"
-}
-
-join_object_assignments_return_3: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                p: 3
-            };
-            return o.q = "foo",
-            o.p += "",
-            console.log(o.q),
-            o.p;
-        }());
-    }
-    expect: {
-        console.log(function() {
-            var o = {
-                p: 3,
-                q: "foo"
-            };
-            return o.p += "",
-            console.log(o.q),
-            o.p;
-        }());
-    }
-    expect_stdout: [
-        "foo",
-        "3",
-    ]
-}
-
-join_object_assignments_for: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {
-                p: 3
-            };
-            for (o.q = "foo"; console.log(o.q););
-            return o.p;
-        }());
-    }
-    expect: {
-        console.log(function() {
-            for (var o = {
-                p: 3,
-                q: "foo"
-            }; console.log(o.q););
-            return o.p;
-        }());
-    }
-    expect_stdout: [
-        "foo",
-        "3",
-    ]
-}
-
-join_object_assignments_if: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {};
-            if (o.a = "PASS") return o.a;
-        }())
-    }
-    expect: {
-        console.log(function() {
-            var o = { a: "PASS" };
-            if (o.a) return o.a;
-        }());
-    }
-    expect_stdout: "PASS"
-}
-
-join_object_assignments_forin: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        console.log(function() {
-            var o = {};
-            for (var a in o.a = "PASS", o)
-                return o[a];
-        }())
-    }
-    expect: {
-        console.log(function() {
-            var o = { a: "PASS" };
-            for (var a in o)
-                return o[a];
-        }());
-    }
-    expect_stdout: "PASS"
-}
-
-join_object_assignments_negative: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[0] = 0;
-        o[-0] = 1;
-        o[-1] = 2;
-        console.log(o[0], o[-0], o[-1]);
-    }
-    expect: {
-        var o = {
-            0: 0,
-            0: 1,
-            "-1": 2
-        };
-        console.log(o[0], o[-0], o[-1]);
-    }
-    expect_stdout: "1 1 2"
-}
-
-join_object_assignments_NaN_1: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {};
-        o[NaN] = 1;
-        o[0/0] = 2;
-        console.log(o[NaN], o[NaN]);
-    }
-    expect: {
-        var o = {};
-        o[NaN] = 1;
-        o[0/0] = 2;
-        console.log(o[NaN], o[NaN]);
-    }
-    expect_stdout: "2 2"
-}
-
-join_object_assignments_NaN_2: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[NaN] = 1;
-        o[0/0] = 2;
-        console.log(o[NaN], o[NaN]);
-    }
-    expect: {
-        var o = {
-            NaN: 1,
-            NaN: 2
-        };
-        console.log(o.NaN, o.NaN);
-    }
-    expect_stdout: "2 2"
-}
-
-join_object_assignments_null_0: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {};
-        o[null] = 1;
-        console.log(o[null]);
-    }
-    expect: {
-        var o = {};
-        o[null] = 1;
-        console.log(o[null]);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_null_1: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[null] = 1;
-        console.log(o[null]);
-    }
-    expect: {
-        var o = {
-            null: 1
-        };
-        console.log(o.null);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_void_0: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-    }
-    input: {
-        var o = {};
-        o[void 0] = 1;
-        console.log(o[void 0]);
-    }
-    expect: {
-        var o = {
-            undefined: 1
-        };
-        console.log(o[void 0]);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_undefined_1: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {};
-        o[undefined] = 1;
-        console.log(o[undefined]);
-    }
-    expect: {
-        var o = {};
-        o[void 0] = 1;
-        console.log(o[void 0]);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_undefined_2: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[undefined] = 1;
-        console.log(o[undefined]);
-    }
-    expect: {
-        var o = {
-            undefined : 1
-        };
-        console.log(o[void 0]);
-    }
-    expect_stdout: "1"
-}
-
-join_object_assignments_Infinity: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[Infinity] = 1;
-        o[1/0] = 2;
-        o[-Infinity] = 3;
-        o[-1/0] = 4;
-        console.log(o[Infinity], o[1/0], o[-Infinity], o[-1/0]);
-    }
-    expect: {
-        var o = {
-            Infinity: 1,
-            Infinity: 2,
-            "-Infinity": 3,
-            "-Infinity": 4
-        };
-        console.log(o[1/0], o[1/0], o[-1/0], o[-1/0]);
-    }
-    expect_stdout: "2 2 4 4"
-}
-
-join_object_assignments_regex: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-        properties: true,
-    }
-    input: {
-        var o = {};
-        o[/rx/] = 1;
-        console.log(o[/rx/]);
-    }
-    expect: {
-        var o = {
-            "/rx/": 1
-        };
-        console.log(o[/rx/]);
-    }
-    expect_stdout: "1"
-}
-
-issue_2816: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        "use strict";
-        var o = {
-            a: 1
-        };
-        o.b = 2;
-        o.a = 3;
-        o.c = 4;
-        console.log(o.a, o.b, o.c);
-    }
-    expect: {
-        "use strict";
-        var o = {
-            a: 1,
-            b: 2
-        };
-        o.a = 3;
-        o.c = 4;
-        console.log(o.a, o.b, o.c);
-    }
-    expect_stdout: "3 2 4"
-}
-
-issue_2893_1: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {
-            get a() {
-                return "PASS";
-            },
-        };
-        o.a = "FAIL";
-        console.log(o.a);
-    }
-    expect: {
-        var o = {
-            get a() {
-                return "PASS";
-            },
-        };
-        o.a = "FAIL";
-        console.log(o.a);
-    }
-    expect_stdout: "PASS"
-}
-
-issue_2893_2: {
-    options = {
-        join_vars: true,
-    }
-    input: {
-        var o = {
-            set a(v) {
-                this.b = v;
-            },
-            b: "FAIL",
-        };
-        o.a = "PASS";
-        console.log(o.b);
-    }
-    expect: {
-        var o = {
-            set a(v) {
-                this.b = v;
-            },
-            b: "FAIL",
-        };
-        o.a = "PASS";
-        console.log(o.b);
-    }
-    expect_stdout: "PASS"
-}
-
 issue_869_1: {
     mangle = {
         properties: {
@@ -1856,36 +1304,6 @@ issue_3188_3: {
     expect_stdout: "PASS"
 }
 
-join_expr: {
-    options = {
-        evaluate: true,
-        join_vars: true,
-    }
-    input: {
-        var c = "FAIL";
-        (function() {
-            var a = 0;
-            switch ((a = {}) && (a.b = 0)) {
-              case 0:
-                c = "PASS";
-            }
-        })();
-        console.log(c);
-    }
-    expect: {
-        var c = "FAIL";
-        (function() {
-            var a = 0;
-            switch (a = { b: 0 }, a.b) {
-              case 0:
-                c = "PASS";
-            }
-        })();
-        console.log(c);
-    }
-    expect_stdout: "PASS"
-}
-
 issue_3389: {
     options = {
         evaluate: true,

test/compress/pure_funcs.js

@@ -680,3 +680,130 @@ issue_3325_2: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3858: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: "strict",
+        unused: true,
+    }
+    input: {
+        var f = function(a) {
+            return /*@__PURE__*/ function(b) {
+                console.log(b);
+            }(a);
+        };
+        f("PASS");
+    }
+    expect: {
+        var f = function(a) {
+            return function() {
+                console.log(a);
+            }();
+        };
+        f("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+inline_pure_call_1: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: "strict",
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var f = function(a) {
+            return /*@__PURE__*/ function(b) {
+                console.log(b);
+            }(a);
+        };
+        f("PASS");
+    }
+    expect: {}
+}
+
+inline_pure_call_2: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        keep_fargs: "strict",
+        reduce_vars: true,
+        sequences: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var f = function(a) {
+            return /*@__PURE__*/ function(b) {
+                console.log(b);
+            }(a);
+        };
+        var a = f("PASS");
+    }
+    expect: {}
+}
+
+inline_pure_call_3: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        keep_fargs: "strict",
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var f = function(a) {
+            return /*@__PURE__*/ function(b) {
+                console.log(b);
+            }(a);
+        };
+        var a = f("PASS");
+        console.log(a);
+    }
+    expect: {
+        var a = function() {
+            console.log("PASS");
+        }();
+        console.log(a);
+    }
+    expect_stdout: [
+        "PASS",
+        "undefined",
+    ]
+}
+
+inline_pure_call_4: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = /*@__PURE__*/ function() {
+            return console.log("PASS"), 42;
+        }();
+        console.log(a);
+    }
+    expect: {
+        var a = function() {
+            return console.log("PASS"), 42;
+        }();
+        console.log(a);
+    }
+    expect_stdout: [
+        "PASS",
+        "42",
+    ]
+}

test/compress/reduce_vars.js

@@ -223,6 +223,25 @@ unsafe_evaluate: {
     expect_stdout: true
 }
 
+unsafe_evaluate_defun: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            function f() {}
+            return ++f;
+        }());
+    }
+    expect: {
+        console.log(NaN);
+    }
+    expect_stdout: "NaN"
+}
+
 unsafe_evaluate_side_effect_free_1: {
     options = {
         evaluate: true,
@@ -1178,11 +1197,10 @@ toplevel_on_loops_1: {
         while (x);
     }
     expect: {
-        function bar() {
-            console.log("bar:", --x);
-        }
         var x = 3;
-        for (;bar(), x;);
+        for (;function() {
+            console.log("bar:", --x);
+        }(), x;);
     }
     expect_stdout: true
 }
@@ -1235,10 +1253,9 @@ toplevel_on_loops_2: {
         while (x);
     }
     expect: {
-        function bar() {
+        for (;;) (function() {
             console.log("bar:");
-        }
-        for (;;) bar();
+        })();
     }
 }
 
@@ -4212,13 +4229,12 @@ issue_2450_4: {
     }
     expect: {
         var a;
-        function f(b) {
-            console.log(a === b);
-            a = b;
-        }
         function g() {}
         for (var i = 3; --i >= 0;)
-            f(g);
+            (function(b) {
+                console.log(a === b);
+                a = b;
+            })(g);
     }
     expect_stdout: [
         "false",
@@ -4319,14 +4335,13 @@ perf_1: {
         console.log(sum);
     }
     expect: {
-        function indirect_foo(x, y, z) {
-            return function(x, y, z) {
-                return x < y ? x * y + z : x * z - y;
-            }(x, y, z);
-        }
         var sum = 0;
         for (var i = 0; i < 100; ++i)
-            sum += indirect_foo(i, i + 1, 3 * i);
+            sum += function(x, y, z) {
+                return function(x, y, z) {
+                    return x < y ? x * y + z : x * z - y;
+                }(x, y, z);
+            }(i, i + 1, 3 * i);
         console.log(sum);
     }
     expect_stdout: "348150"
@@ -4387,14 +4402,13 @@ perf_3: {
         console.log(sum);
     }
     expect: {
-        var indirect_foo = function(x, y, z) {
-            return function(x, y, z) {
-                return x < y ? x * y + z : x * z - y;
-            }(x, y, z);
-        }
         var sum = 0;
         for (var i = 0; i < 100; ++i)
-            sum += indirect_foo(i, i + 1, 3 * i);
+            sum += function(x, y, z) {
+                return function(x, y, z) {
+                    return x < y ? x * y + z : x * z - y;
+                }(x, y, z);
+            }(i, i + 1, 3 * i);
         console.log(sum);
     }
     expect_stdout: "348150"
@@ -4456,14 +4470,13 @@ perf_5: {
         console.log(sum);
     }
     expect: {
-        function indirect_foo(x, y, z) {
-            return function(x, y, z) {
-                return x < y ? x * y + z : x * z - y;
-            }(x, y, z);
-        }
         var sum = 0;
         for (var i = 0; i < 100; ++i)
-            sum += indirect_foo(i, i + 1, 3 * i);
+            sum += function(x, y, z) {
+                return function(x, y, z) {
+                    return x < y ? x * y + z : x * z - y;
+                }(x, y, z);
+            }(i, i + 1, 3 * i);
         console.log(sum);
     }
     expect_stdout: "348150"
@@ -4524,14 +4537,13 @@ perf_7: {
         console.log(sum);
     }
     expect: {
-        var indirect_foo = function(x, y, z) {
-            return function(x, y, z) {
-                return x < y ? x * y + z : x * z - y;
-            }(x, y, z);
-        }
         var sum = 0;
         for (var i = 0; i < 100; ++i)
-            sum += indirect_foo(i, i + 1, 3 * i);
+            sum += function(x, y, z) {
+                return function(x, y, z) {
+                    return x < y ? x * y + z : x * z - y;
+                }(x, y, z);
+            }(i, i + 1, 3 * i);
         console.log(sum);
     }
     expect_stdout: "348150"
@@ -4570,7 +4582,7 @@ perf_8: {
     expect_stdout: "348150"
 }
 
-issue_2485: {
+issue_2485_1: {
     options = {
         reduce_funcs: true,
         reduce_vars: true,
@@ -4618,6 +4630,53 @@ issue_2485: {
     expect_stdout: "6"
 }
 
+issue_2485_2: {
+    options = {
+        inline: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        var foo = function(bar) {
+            var n = function(a, b) {
+                return a + b;
+            };
+            var sumAll = function(arg) {
+                return arg.reduce(n, 0);
+            };
+            var runSumAll = function(arg) {
+                return sumAll(arg);
+            };
+            bar.baz = function(arg) {
+                var n = runSumAll(arg);
+                return (n.get = 1), n;
+            };
+            return bar;
+        };
+        var bar = foo({});
+        console.log(bar.baz([1, 2, 3]));
+    }
+    expect: {
+        var foo = function(bar) {
+            var n = function(a, b) {
+                return a + b;
+            };
+            var runSumAll = function(arg) {
+                    return arg.reduce(n, 0);
+            };
+            bar.baz = function(arg) {
+                var n = runSumAll(arg);
+                return (n.get = 1), n;
+            };
+            return bar;
+        };
+        var bar = foo({});
+        console.log(bar.baz([1, 2, 3]));
+    }
+    expect_stdout: "6"
+}
+
 issue_2455: {
     options = {
         reduce_vars: true,
@@ -5434,8 +5493,7 @@ lvalues_def_1: {
     }
     expect: {
         var b = 1;
-        var a = b++;
-        b = NaN;
+        var a = b++, b = NaN;
         console.log(a, b);
     }
     expect_stdout: "1 NaN"
@@ -5454,8 +5512,7 @@ lvalues_def_2: {
     }
     expect: {
         var b = 1;
-        var a = b += 1;
-        b = NaN;
+        var a = b += 1, b = NaN;
         console.log(a, b);
     }
     expect_stdout: "2 NaN"
@@ -6867,9 +6924,9 @@ issue_3666: {
         } finally {
             for (;!a;)
                 a++;
-            var b = a = "PASS";
+            a = "PASS";
         }
-        console.log(a, b);
+        console.log(a, "PASS");
     }
     expect_stdout: "PASS PASS"
 }
@@ -6912,3 +6969,102 @@ issue_3774: {
     }
     expect_stdout: "PASS"
 }
+
+flatten_iife: {
+    options = {
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = "FAIL";
+        while (!console);
+        a++;
+        (function() {
+            while (!console);
+            a = "PASS";
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a;
+        while (!console);
+        0;
+        (function() {
+            while (!console);
+            a = "PASS";
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3844: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        console.log(function() {
+            if (!console) switch (A = 0) {
+              case console.log("FAIL"):
+                return;
+            }
+            return typeof A;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            if (!console) switch (A = 0) {
+              case console.log("FAIL"):
+                return;
+            }
+            return typeof A;
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+issue_3866: {
+    options = {
+        dead_code: true,
+        evaluate: true,
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function() {
+            {
+                return "PASS";
+                var a = 0;
+            }
+            return --a;
+        }());
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3880: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a) {
+            while (a.var ^= 1);
+            console.log("PASS");
+        })(function() {});
+    }
+    expect: {
+        (function(a) {
+            while (a.var ^= 1);
+            console.log("PASS");
+        })(function() {});
+    }
+    expect_stdout: "PASS"
+}

test/compress/transform.js

@@ -69,6 +69,7 @@ label_if_break: {
         dead_code: true,
         evaluate: true,
         side_effects: true,
+        unused: true,
     }
     input: {
         L: if (true) {

test/compress/typeof.js

@@ -435,3 +435,25 @@ emberjs_global: {
     }
     expect_stdout: Error("PASS")
 }
+
+issue_3817: {
+    options = {
+        comparisons: true,
+        conditionals: true,
+        passes: 2,
+        typeofs: true,
+    }
+    input: {
+        if ("A" == typeof A || !console.log("PASS")) switch (false) {
+          case "undefined" == typeof A:
+            console.log("FAIL");
+        }
+    }
+    expect: {
+        if ("A" == typeof A || !console.log("PASS")) switch (false) {
+          case "undefined" == typeof A:
+            console.log("FAIL");
+        }
+    }
+    expect_stdout: "PASS"
+}

test/input/issue-3040/expect.js

@@ -1,2 +1,41 @@
-function _toConsumableArray(arr){if(Array.isArray(arr)){for(var i=0,arr2=Array(arr.length);i<arr.length;i++){arr2[i]=arr[i]}return arr2}else{return Array.from(arr)}}var _require=require("bar"),foo=_require.foo;var _require2=require("world"),hello=_require2.hello;foo.x.apply(foo,_toConsumableArray(foo.y(hello.z)));
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbImlucHV0Mi5qcyJdLCJzb3VyY2VzQ29udGVudCI6WyJjb25zdCB7Zm9vfSA9IHJlcXVpcmUoXCJiYXJcIik7XG5jb25zdCB7aGVsbG99ID0gcmVxdWlyZShcIndvcmxkXCIpO1xuXG5mb28ueCguLi5mb28ueShoZWxsby56KSk7XG4iXSwibmFtZXMiOlsicmVxdWlyZSIsImFyciJdLCJtYXBwaW5ncyI6IjBKQUFjQSxLQUFRQyJ9
+"use strict";
+
+function _toConsumableArray(arr) {
+    return _arrayWithoutHoles(arr) || _iterableToArray(arr) || _unsupportedIterableToArray(arr) || _nonIterableSpread();
+}
+
+function _nonIterableSpread() {
+    throw new TypeError("Invalid attempt to spread non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method.");
+}
+
+function _unsupportedIterableToArray(o, minLen) {
+    if (!o) return;
+    if (typeof o === "string") return _arrayLikeToArray(o, minLen);
+    var n = Object.prototype.toString.call(o).slice(8, -1);
+    if (n === "Object" && o.constructor) n = o.constructor.name;
+    if (n === "Map" || n === "Set") return Array.from(n);
+    if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen);
+}
+
+function _iterableToArray(iter) {
+    if (typeof Symbol !== "undefined" && Symbol.iterator in Object(iter)) return Array.from(iter);
+}
+
+function _arrayWithoutHoles(arr) {
+    if (Array.isArray(arr)) return _arrayLikeToArray(arr);
+}
+
+function _arrayLikeToArray(arr, len) {
+    if (len == null || len > arr.length) len = arr.length;
+    for (var i = 0, arr2 = new Array(len); i < len; i++) {
+        arr2[i] = arr[i];
+    }
+    return arr2;
+}
+
+var _require = require("bar"), foo = _require.foo;
+
+var _require2 = require("world"), hello = _require2.hello;
+
+foo.x.apply(foo, _toConsumableArray(foo.y(hello.z)));
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,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

test/input/issue-3040/input.js

@@ -1,4 +1,16 @@
-function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } }
+"use strict";
+
+function _toConsumableArray(arr) { return _arrayWithoutHoles(arr) || _iterableToArray(arr) || _unsupportedIterableToArray(arr) || _nonIterableSpread(); }
+
+function _nonIterableSpread() { throw new TypeError("Invalid attempt to spread non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); }
+
+function _unsupportedIterableToArray(o, minLen) { if (!o) return; if (typeof o === "string") return _arrayLikeToArray(o, minLen); var n = Object.prototype.toString.call(o).slice(8, -1); if (n === "Object" && o.constructor) n = o.constructor.name; if (n === "Map" || n === "Set") return Array.from(n); if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen); }
+
+function _iterableToArray(iter) { if (typeof Symbol !== "undefined" && Symbol.iterator in Object(iter)) return Array.from(iter); }
+
+function _arrayWithoutHoles(arr) { if (Array.isArray(arr)) return _arrayLikeToArray(arr); }
+
+function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0, arr2 = new Array(len); i < len; i++) { arr2[i] = arr[i]; } return arr2; }
 
 var _require = require("bar"),
     foo = _require.foo;

test/input/issue-3040/input.js.map

@@ -1 +1,11 @@
-{"version":3,"sources":["input2.js"],"names":["require","foo","hello","x","apply","_toConsumableArray","y","z"],"mappings":"kLAAcA,QAAQ,OAAfC,aAAAA,kBACSD,QAAQ,SAAjBE,gBAAAA,MAEPD,IAAIE,EAAJC,MAAAH,IAAAI,mBAASJ,IAAIK,EAAEJ,MAAMK","sourcesContent":["const {foo} = require(\"bar\");\nconst {hello} = require(\"world\");\n\nfoo.x(...foo.y(hello.z));\n"]}
+{
+    "version": 3,
+    "sources": [
+        "input.js"
+    ],
+    "names": [],
+    "mappings": ";;;;;;;;;;;;;;eAAc,OAAO,CAAC,KAAD,C;IAAd,G,YAAA,G;;gBACS,OAAO,CAAC,OAAD,C;IAAhB,K,aAAA,K;;AAEP,GAAG,CAAC,CAAJ,OAAA,GAAG,qBAAM,GAAG,CAAC,CAAJ,CAAM,KAAK,CAAC,CAAZ,CAAN,EAAH",
+    "sourcesContent": [
+        "const {foo} = require(\"bar\");\nconst {hello} = require(\"world\");\n\nfoo.x(...foo.y(hello.z));\n"
+    ]
+}

test/input/issue-505/output.js

@@ -2,4 +2,4 @@ function test(a){
 "aaaaaaaaaaaaaaaa"
 ;a(err,data),a(err,
 data)}
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsidGVzdCIsImNhbGxiYWNrIiwiZXJyIiwiZGF0YSJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0EsS0FBS0M7QUFDVjtDQUNBQSxFQUFTQyxJQUFLQyxNQUNkRixFQUFTQztBQUFLQyJ9
+//# sourceMappingURL=data:application/json;charset=utf-8;base64,eyJ2ZXJzaW9uIjozLCJzb3VyY2VzIjpbIjAiXSwibmFtZXMiOlsidGVzdCIsImNhbGxiYWNrIiwiZXJyIiwiZGF0YSJdLCJtYXBwaW5ncyI6IkFBQUEsU0FBU0EsS0FBS0M7O0NBRVZBLEVBQVNDLElBQUtDLE1BQ2RGLEVBQVNDO0FBQUtDIn0=

test/jetstream.js

@@ -14,9 +14,9 @@ if (typeof phantom == "undefined") {
         args.splice(debug, 1);
         debug = true;
     }
-    args.unshift("bin/uglifyjs");
     if (!args.length) args.push("-mcb", "beautify=false,webkit");
-    args.push("--timings");
+    args.unshift("bin/uglifyjs");
+    args.push("--validate", "--timings");
     var child_process = require("child_process");
     var fetch = require("./fetch");
     var http = require("http");
@@ -41,7 +41,7 @@ if (typeof phantom == "undefined") {
                     var uglifyjs = child_process.spawn(process.argv[0], args, {
                         silent: true
                     }).on("exit", function(code) {
-                        console.log("uglifyjs", url.slice(site.length + 1), args.join(" "));
+                        console.log("uglifyjs", url.slice(site.length + 1), args.slice(1).join(" "));
                         console.log(stderr);
                         if (code) throw new Error("uglifyjs failed with code " + code);
                     });

test/mocha/cli.js

@@ -2,6 +2,7 @@ var assert = require("assert");
 var exec = require("child_process").exec;
 var fs = require("fs");
 var run_code = require("../sandbox").run_code;
+var to_ascii = require("../node").to_ascii;
 
 function read(path) {
     return fs.readFileSync(path, "utf8");
@@ -48,6 +49,62 @@ describe("bin/uglifyjs", function() {
             done();
         });
     });
+    it("Should work with --source-map names=true", function(done) {
+        exec([
+            uglifyjscmd,
+            "--beautify",
+            "--source-map", [
+                "names=true",
+                "url=inline",
+            ].join(","),
+        ].join(" "), function(err, stdout) {
+            if (err) throw err;
+            var expected = [
+                "var obj = {",
+                "    p: a,",
+                "    q: b",
+                "};",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,",
+            ].join("\n")
+            assert.strictEqual(stdout.slice(0, expected.length), expected);
+            var map = JSON.parse(to_ascii(stdout.slice(expected.length).trim()));
+            assert.deepEqual(map.names, [ "obj", "p", "a", "q", "b" ]);
+            done();
+        }).stdin.end([
+            "var obj = {",
+            "    p: a,",
+            "    q: b",
+            "};",
+        ].join("\n"));
+    });
+    it("Should work with --source-map names=false", function(done) {
+        exec([
+            uglifyjscmd,
+            "--beautify",
+            "--source-map", [
+                "names=false",
+                "url=inline",
+            ].join(","),
+        ].join(" "), function(err, stdout) {
+            if (err) throw err;
+            var expected = [
+                "var obj = {",
+                "    p: a,",
+                "    q: b",
+                "};",
+                "//# sourceMappingURL=data:application/json;charset=utf-8;base64,",
+            ].join("\n")
+            assert.strictEqual(stdout.slice(0, expected.length), expected);
+            var map = JSON.parse(to_ascii(stdout.slice(expected.length).trim()));
+            assert.deepEqual(map.names, []);
+            done();
+        }).stdin.end([
+            "var obj = {",
+            "    p: a,",
+            "    q: b",
+            "};",
+        ].join("\n"));
+    });
     it("Should give sensible error against invalid input source map", function(done) {
         var command = uglifyjscmd + " test/mocha.js --source-map content=blah,url=inline --verbose";
         exec(command, function(err, stdout, stderr) {
@@ -109,9 +166,12 @@ describe("bin/uglifyjs", function() {
         }
         var command = [
             uglifyjscmd,
-            "--source-map", "content=" + mapFile,
-            "--source-map", "includeSources=true",
-            "--source-map", "url=inline",
+            "--beautify",
+            "--source-map", [
+                "content=" + mapFile,
+                "includeSources",
+                "url=inline",
+            ].join(","),
         ].join(" ");
 
         var child = exec(command, function(err, stdout) {

test/mocha/minify.js

@@ -1,7 +1,7 @@
 var assert = require("assert");
 var readFileSync = require("fs").readFileSync;
 var run_code = require("../sandbox").run_code;
-var UglifyJS = require("../../");
+var UglifyJS = require("../..");
 
 function read(path) {
     return readFileSync(path, "utf8");
@@ -9,18 +9,30 @@ function read(path) {
 
 describe("minify", function() {
     it("Should test basic sanity of minify with default options", function() {
-        var js = 'function foo(bar) { if (bar) return 3; else return 7; var u = not_called(); }';
+        var js = "function foo(bar) { if (bar) return 3; else return 7; var u = not_called(); }";
         var result = UglifyJS.minify(js);
-        assert.strictEqual(result.code, 'function foo(n){return n?3:7}');
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, "function foo(n){return n?3:7}");
     });
-
+    it("Should not mutate minify `options`", function() {
+        var options = {
+            compress: true,
+            mangle: false,
+            output: {},
+        };
+        var value = JSON.stringify(options);
+        var result = UglifyJS.minify("print(6 * 7);", options);
+        if (result.error) throw result.error;
+        assert.strictEqual(result.code, "print(42);");
+        assert.strictEqual(JSON.stringify(options), value);
+    })
     it("Should skip inherited keys from `files`", function() {
         var files = Object.create({ skip: this });
         files[0] = "alert(1 + 1)";
         var result = UglifyJS.minify(files);
+        if (result.error) throw result.error;
         assert.strictEqual(result.code, "alert(2);");
     });
-
     it("Should work with mangle.cache", function() {
         var cache = {};
         var original = "";
@@ -53,7 +65,6 @@ describe("minify", function() {
         ].join(""));
         assert.strictEqual(run_code(compressed, true), run_code(original, true));
     });
-
     it("Should work with nameCache", function() {
         var cache = {};
         var original = "";
@@ -86,7 +97,6 @@ describe("minify", function() {
         ].join(""));
         assert.strictEqual(run_code(compressed, true), run_code(original, true));
     });
-
     it("Should avoid cached names when mangling top-level variables", function() {
         var cache = {};
         var original = "";
@@ -115,7 +125,6 @@ describe("minify", function() {
         ].join(""));
         assert.strictEqual(run_code(compressed, true), run_code(original, true));
     });
-
     it("Should avoid cached names when mangling inner-scoped variables", function() {
         var cache = {};
         var original = "";
@@ -139,7 +148,6 @@ describe("minify", function() {
         ].join(""));
         assert.strictEqual(run_code(compressed, true), run_code(original, true));
     });
-
     it("Should not parse invalid use of reserved words", function() {
         assert.strictEqual(UglifyJS.minify("function enum(){}").error, undefined);
         assert.strictEqual(UglifyJS.minify("function static(){}").error, undefined);
@@ -155,7 +163,6 @@ describe("minify", function() {
                 }});
             assert.strictEqual(result.code, 'var foo={"x":1,y:2,"z":3};');
         });
-
         it("Should preserve quote styles when quote_style is 3", function() {
             var js = 'var foo = {"x": 1, y: 2, \'z\': 3};';
             var result = UglifyJS.minify(js, {
@@ -165,7 +172,6 @@ describe("minify", function() {
                 }});
             assert.strictEqual(result.code, 'var foo={"x":1,y:2,\'z\':3};');
         });
-
         it("Should not preserve quotes in object literals when disabled", function() {
             var js = 'var foo = {"x": 1, y: 2, \'z\': 3};';
             var result = UglifyJS.minify(js, {

test/mocha/reduce.js

@@ -246,4 +246,54 @@ describe("test/reduce.js", function() {
             "// }",
         ].join("\n"));
     });
+    it("Should reduce test case which differs only in Error.message", function() {
+        var code = [
+            "var a=0;",
+            "try{",
+            "null[function(){}]",
+            "}catch(e){",
+            "for(var i in e.toString())",
+            "a++,console.log()",
+            "}",
+            "console.log(a);",
+        ].join("");
+        var result = reduce_test(code, {
+            compress: false,
+            mangle: false,
+            output: {
+                beautify: true,
+            },
+        });
+        if (result.error) throw result.error;
+        assert.deepEqual(result.warnings, []);
+        assert.strictEqual(result.code.replace(/function \(/g, "function("), (semver.satisfies(process.version, "<=0.10") ? [
+            "// Can't reproduce test failure",
+            "// minify options: {",
+            '//   "compress": false,',
+            '//   "mangle": false,',
+            '//   "output": {',
+            '//     "beautify": true',
+            "//   }",
+            "// }",
+        ] : [
+            [
+                "try{",
+                "null[function(){}]",
+                "}catch(e){",
+                "console.log(e)",
+                "}",
+            ].join(""),
+            "// output: TypeError: Cannot read property 'function(){}' of null",
+            "// ",
+            "// minify: TypeError: Cannot read property 'function() {}' of null",
+            "// ",
+            "// options: {",
+            '//   "compress": false,',
+            '//   "mangle": false,',
+            '//   "output": {',
+            '//     "beautify": true',
+            "//   }",
+            "// }",
+        ]).join("\n"));
+    });
 });

test/mocha/sourcemaps.js

@@ -7,11 +7,13 @@ function read(path) {
 }
 
 function source_map(code) {
-    return JSON.parse(UglifyJS.minify(code, {
+    var result = UglifyJS.minify(code, {
         compress: false,
         mangle: false,
         sourceMap: true,
-    }).map);
+    });
+    if (result.error) throw result.error;
+    return JSON.parse(result.map);
 }
 
 function get_map() {
@@ -65,6 +67,40 @@ describe("sourcemaps", function() {
         ].join("\n"));
         assert.deepEqual(map.names, [ "enabled", "x" ]);
     });
+    it("Should work with sourceMap.names=true", function() {
+        var result = UglifyJS.minify([
+            "var obj = {",
+            "    p: a,",
+            "    q: b",
+            "};",
+        ].join("\n"), {
+            compress: false,
+            mangle: false,
+            sourceMap: {
+                names: true,
+            },
+        });
+        if (result.error) throw result.error;
+        var map = JSON.parse(result.map);
+        assert.deepEqual(map.names, [ "obj", "p", "a", "q", "b" ]);
+    });
+    it("Should work with sourceMap.names=false", function() {
+        var result = UglifyJS.minify([
+            "var obj = {",
+            "    p: a,",
+            "    q: b",
+            "};",
+        ].join("\n"), {
+            compress: false,
+            mangle: false,
+            sourceMap: {
+                names: false,
+            },
+        });
+        if (result.error) throw result.error;
+        var map = JSON.parse(result.map);
+        assert.deepEqual(map.names, []);
+    });
     it("Should mark array/object literals", function() {
         var result = UglifyJS.minify([
             "var obj = {};",

test/mozilla-ast.js

@@ -24,11 +24,22 @@ function try_beautify(code) {
     }
 }
 
-function test(original, estree, description) {
-    var transformed = UglifyJS.minify(UglifyJS.AST_Node.from_mozilla_ast(estree), {
+function validate(ast) {
+    try {
+        ast.walk(new UglifyJS.TreeWalker(function(node) {
+            node.validate();
+        }));
+    } catch (e) {
+        return { error: e };
+    }
+    return UglifyJS.minify(ast, {
         compress: false,
-        mangle: false
+        mangle: false,
     });
+}
+
+function test(original, estree, description) {
+    var transformed = validate(UglifyJS.AST_Node.from_mozilla_ast(estree));
     if (transformed.error || original !== transformed.code) {
         console.log("//=============================================================");
         console.log("// !!!!!! Failed... round", round);

test/reduce.js

@@ -1,5 +1,5 @@
 var crypto = require("crypto");
-var U = require("./node");
+var U = require("..");
 var List = U.List;
 var os = require("os");
 var sandbox = require("./sandbox");
@@ -18,20 +18,30 @@ var sandbox = require("./sandbox");
 // will produce different output from the code minified with `minify_options`.
 // Returns a `minify` result object with an additonal boolean property `reduced`.
 
+Error.stackTraceLimit = Infinity;
 module.exports = function reduce_test(testcase, minify_options, reduce_options) {
     if (testcase instanceof U.AST_Node) testcase = testcase.print_to_string();
     minify_options = minify_options || {};
     reduce_options = reduce_options || {};
     var max_iterations = reduce_options.max_iterations || 1000;
     var max_timeout = reduce_options.max_timeout || 10000;
+    var warnings = [];
+    var log = reduce_options.log || function(msg) {
+        warnings.push(msg);
+    };
     var verbose = reduce_options.verbose;
     var minify_options_json = JSON.stringify(minify_options, null, 2);
     var result_cache = Object.create(null);
+    var test_for_diff = compare_run_code;
     // the initial timeout to assess the viability of the test case must be large
-    var differs = producesDifferentResultWhenMinified(result_cache, testcase, minify_options, max_timeout);
+    var differs = test_for_diff(testcase, minify_options, result_cache, max_timeout);
 
     if (verbose) {
-        console.error("// Node.js " + process.version + " on " + os.platform() + " " + os.arch());
+        log("// Node.js " + process.version + " on " + os.platform() + " " + os.arch());
+    }
+    if (differs.error && [ "DefaultsError", "SyntaxError" ].indexOf(differs.error.name) < 0) {
+        test_for_diff = test_minify;
+        differs = test_for_diff(testcase, minify_options, result_cache, max_timeout);
     }
     if (!differs) {
         // same stdout result produced when minified
@@ -39,16 +49,19 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             code: [
                 "// Can't reproduce test failure",
                 "// minify options: " + to_comment(minify_options_json)
-            ].join("\n")
+            ].join("\n"),
+            warnings: warnings,
         };
     } else if (differs.timed_out) {
         return {
             code: [
                 "// Can't reproduce test failure within " + max_timeout + "ms",
                 "// minify options: " + to_comment(minify_options_json)
-            ].join("\n")
+            ].join("\n"),
+            warnings: warnings,
         };
     } else if (differs.error) {
+        differs.warnings = warnings;
         return differs;
     } else if (is_error(differs.unminified_result)
         && is_error(differs.minified_result)
@@ -57,7 +70,8 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             code: [
                 "// No differences except in error message",
                 "// minify options: " + to_comment(minify_options_json)
-            ].join("\n")
+            ].join("\n"),
+            warnings: warnings,
         };
     } else {
         max_timeout = Math.min(100 * differs.elapsed, max_timeout);
@@ -125,40 +139,13 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 }
             }
             else if (node instanceof U.AST_Binary) {
-                CHANGED = true;
                 var permute = ((node.start._permute += step) * steps | 0) % 4;
                 var expr = [
                     node.left,
                     node.right,
                 ][ permute & 1 ];
-                if (permute < 2) return expr;
-                // wrap with console.log()
-                return new U.AST_Call({
-                    expression: new U.AST_Dot({
-                        expression: new U.AST_SymbolRef({
-                            name: "console",
-                            start: {},
-                        }),
-                        property: "log",
-                        start: {},
-                    }),
-                    args: [ expr ],
-                    start: {},
-                });
-            }
-            else if (node instanceof U.AST_Catch || node instanceof U.AST_Finally) {
-                // drop catch or finally block
-                node.start._permute++;
                 CHANGED = true;
-                return null;
-            }
-            else if (node instanceof U.AST_Conditional) {
-                CHANGED = true;
-                return [
-                    node.condition,
-                    node.consequent,
-                    node.alternative,
-                ][ ((node.start._permute += step) * steps | 0) % 3 ];
+                return permute < 2 ? expr : wrap_with_console_log(expr);
             }
             else if (node instanceof U.AST_BlockStatement) {
                 if (in_list) {
@@ -193,12 +180,26 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     return to_sequence(seq);
                 }
             }
+            else if (node instanceof U.AST_Catch) {
+                // drop catch block
+                node.start._permute++;
+                CHANGED = true;
+                return null;
+            }
+            else if (node instanceof U.AST_Conditional) {
+                CHANGED = true;
+                return [
+                    node.condition,
+                    node.consequent,
+                    node.alternative,
+                ][ ((node.start._permute += step) * steps | 0) % 3 ];
+            }
             else if (node instanceof U.AST_Defun) {
                 switch (((node.start._permute += step) * steps | 0) % 2) {
                   case 0:
                     CHANGED = true;
                     return List.skip;
-                  case 1:
+                  default:
                     if (!has_exit(node)) {
                         // hoist function declaration body
                         var body = node.body;
@@ -230,15 +231,11 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     return to_statement(expr);
                 }
             }
-            else if (node instanceof U.AST_PropAccess) {
-                var expr = [
-                    node.expression,
-                    node.property instanceof U.AST_Node && node.property,
-                ][ node.start._permute++ % 2 ];
-                if (expr) {
-                    CHANGED = true;
-                    return expr;
-                }
+            else if (node instanceof U.AST_Finally) {
+                // drop finally block
+                node.start._permute++;
+                CHANGED = true;
+                return null;
             }
             else if (node instanceof U.AST_For) {
                 var expr = [
@@ -287,6 +284,16 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     return expr;
                 }
             }
+            else if (node instanceof U.AST_PropAccess) {
+                var expr = [
+                    node.expression,
+                    node.property instanceof U.AST_Node && node.property,
+                ][ node.start._permute++ % 2 ];
+                if (expr) {
+                    CHANGED = true;
+                    return expr;
+                }
+            }
             else if (node instanceof U.AST_SimpleStatement) {
                 if (node.body instanceof U.AST_Call && node.body.expression instanceof U.AST_Function) {
                     // hoist simple statement IIFE function expression body
@@ -414,19 +421,41 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             }
         });
 
+        var diff_error_message;
         for (var pass = 1; pass <= 3; ++pass) {
             var testcase_ast = U.parse(testcase);
+            if (diff_error_message === testcase) {
+                // only difference detected is in error message, so expose that and try again
+                testcase_ast.transform(new U.TreeTransformer(function(node, descend) {
+                    if (node.TYPE == "Call" && node.expression.print_to_string() == "console.log") {
+                        return to_sequence(node.args);
+                    }
+                    if (node instanceof U.AST_Catch) {
+                        descend(node, this);
+                        node.body.unshift(new U.AST_SimpleStatement({
+                            body: wrap_with_console_log(new U.AST_SymbolRef(node.argname)),
+                            start: {},
+                        }));
+                        return node;
+                    }
+                }));
+                var code = testcase_ast.print_to_string();
+                if (diff = test_for_diff(code, minify_options, result_cache, max_timeout)) {
+                    testcase = code;
+                    differs = diff;
+                } else {
+                    testcase_ast = U.parse(testcase);
+                }
+            }
+            diff_error_message = null;
             testcase_ast.walk(new U.TreeWalker(function(node) {
                 // unshare start props to retain visit data between iterations
                 node.start = JSON.parse(JSON.stringify(node.start));
                 node.start._permute = 0;
             }));
             for (var c = 0; c < max_iterations; ++c) {
-                if (verbose) {
-                    if (pass == 1 && c % 25 == 0) {
-                        console.error("// reduce test pass "
-                            + pass + ", iteration " + c + ": " + testcase.length + " bytes");
-                    }
+                if (verbose && pass == 1 && c % 25 == 0) {
+                    log("// reduce test pass " + pass + ", iteration " + c + ": " + testcase.length + " bytes");
                 }
                 var CHANGED = false;
                 var code_ast = testcase_ast.clone(true).transform(tt);
@@ -436,12 +465,12 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 } catch (ex) {
                     // AST is not well formed.
                     // no harm done - just log the error, ignore latest change and continue iterating.
-                    console.error("*** Error generating code from AST.");
-                    console.error(ex);
-                    console.error("*** Discarding permutation and continuing.");
+                    log("*** Error generating code from AST.");
+                    log(ex.stack);
+                    log("*** Discarding permutation and continuing.");
                     continue;
                 }
-                var diff = producesDifferentResultWhenMinified(result_cache, code, minify_options, max_timeout);
+                var diff = test_for_diff(code, minify_options, result_cache, max_timeout);
                 if (diff) {
                     if (diff.timed_out) {
                         // can't trust the validity of `code_ast` and `code` when timed out.
@@ -449,14 +478,15 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     } else if (diff.error) {
                         // something went wrong during minify() - could be malformed AST or genuine bug.
                         // no harm done - just log code & error, ignore latest change and continue iterating.
-                        console.error("*** Error during minification.");
-                        console.error(code);
-                        console.error(diff.error);
-                        console.error("*** Discarding permutation and continuing.");
+                        log("*** Error during minification.");
+                        log(code);
+                        log(diff.error.stack);
+                        log("*** Discarding permutation and continuing.");
                     } else if (is_error(diff.unminified_result)
                         && is_error(diff.minified_result)
                         && diff.unminified_result.name == diff.minified_result.name) {
                         // ignore difference in error messages caused by minification
+                        diff_error_message = testcase;
                     } else {
                         // latest permutation is valid, so use it as the basis of new changes
                         testcase_ast = code_ast;
@@ -467,27 +497,32 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             }
             if (c == 0) break;
             if (verbose) {
-                console.error("// reduce test pass " + pass + ": " + testcase.length + " bytes");
+                log("// reduce test pass " + pass + ": " + testcase.length + " bytes");
             }
         }
-        testcase = try_beautify(result_cache, testcase, minify_options, differs.unminified_result, max_timeout);
+        testcase = try_beautify(testcase, minify_options, differs.unminified_result, result_cache, max_timeout);
         var lines = [ "" ];
-        var unminified_result = strip_color_codes(differs.unminified_result);
-        var minified_result = strip_color_codes(differs.minified_result);
-        if (trim_trailing_whitespace(unminified_result) == trim_trailing_whitespace(minified_result)) {
-            lines.push(
-                "// (stringified)",
-                "// output: " + JSON.stringify(unminified_result),
-                "// minify: " + JSON.stringify(minified_result)
-            );
+        if (isNaN(max_timeout)) {
+            lines.push("// minify error: " + to_comment(strip_color_codes(differs.minified_result.stack)));
         } else {
-            lines.push(
-                "// output: " + to_comment(unminified_result),
-                "// minify: " + to_comment(minified_result)
-            );
+            var unminified_result = strip_color_codes(differs.unminified_result);
+            var minified_result = strip_color_codes(differs.minified_result);
+            if (trim_trailing_whitespace(unminified_result) == trim_trailing_whitespace(minified_result)) {
+                lines.push(
+                    "// (stringified)",
+                    "// output: " + JSON.stringify(unminified_result),
+                    "// minify: " + JSON.stringify(minified_result)
+                );
+            } else {
+                lines.push(
+                    "// output: " + to_comment(unminified_result),
+                    "// minify: " + to_comment(minified_result)
+                );
+            }
         }
         lines.push("// options: " + to_comment(minify_options_json));
         testcase.code += lines.join("\n");
+        testcase.warnings = warnings;
         return testcase;
     }
 };
@@ -504,7 +539,7 @@ function trim_trailing_whitespace(value) {
     return ("" + value).replace(/\s+$/, "");
 }
 
-function try_beautify(result_cache, testcase, minify_options, expected, timeout) {
+function try_beautify(testcase, minify_options, expected, result_cache, timeout) {
     var result = U.minify(testcase, {
         compress: false,
         mangle: false,
@@ -518,10 +553,16 @@ function try_beautify(result_cache, testcase, minify_options, expected, timeout)
         code: testcase,
     };
     var toplevel = sandbox.has_toplevel(minify_options);
-    var actual = run_code(result_cache, result.code, toplevel, timeout);
-    if (!sandbox.same_stdout(expected, actual)) return {
-        code: testcase,
-    };
+    if (isNaN(timeout)) {
+        if (!U.minify(result.code, minify_options).error) return {
+            code: testcase,
+        };
+    } else {
+        var actual = run_code(result.code, toplevel, result_cache, timeout);
+        if (!sandbox.same_stdout(expected, actual)) return {
+            code: testcase,
+        };
+    }
     result.code = "// (beautified)\n" + result.code;
     return result;
 }
@@ -592,21 +633,37 @@ function to_statement(node) {
     });
 }
 
-function run_code(result_cache, code, toplevel, timeout) {
+function wrap_with_console_log(node) {
+    // wrap with console.log()
+    return new U.AST_Call({
+        expression: new U.AST_Dot({
+            expression: new U.AST_SymbolRef({
+                name: "console",
+                start: {},
+            }),
+            property: "log",
+            start: {},
+        }),
+        args: [ node ],
+        start: {},
+    });
+}
+
+function run_code(code, toplevel, result_cache, timeout) {
     var key = crypto.createHash("sha1").update(code).digest("base64");
     return result_cache[key] || (result_cache[key] = sandbox.run_code(code, toplevel, timeout));
 }
 
-function producesDifferentResultWhenMinified(result_cache, code, minify_options, max_timeout) {
+function compare_run_code(code, minify_options, result_cache, max_timeout) {
     var minified = U.minify(code, minify_options);
     if (minified.error) return minified;
 
     var toplevel = sandbox.has_toplevel(minify_options);
     var elapsed = Date.now();
-    var unminified_result = run_code(result_cache, code, toplevel, max_timeout);
+    var unminified_result = run_code(code, toplevel, result_cache, max_timeout);
     elapsed = Date.now() - elapsed;
     var timeout = Math.min(100 * elapsed, max_timeout);
-    var minified_result = run_code(result_cache, minified.code, toplevel, timeout);
+    var minified_result = run_code(minified.code, toplevel, result_cache, timeout);
 
     if (sandbox.same_stdout(unminified_result, minified_result)) {
         return is_timed_out(unminified_result) && is_timed_out(minified_result) && {
@@ -619,4 +676,10 @@ function producesDifferentResultWhenMinified(result_cache, code, minify_options,
         elapsed: elapsed,
     };
 }
-Error.stackTraceLimit = Infinity;
+
+function test_minify(code, minify_options) {
+    var minified = U.minify(code, minify_options);
+    return minified.error && {
+        minified_result: minified.error,
+    };
+}

test/ufuzz/index.js

@@ -764,20 +764,22 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
         return createObjectLiteral(recurmax, stmtDepth, canThrow) + "." + getDotKey();
       case p++:
         var name = getVarName();
-        return name + " && " + name + "[" + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "]";
+        var s = name + "[" + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "]";
+        return canThrow && rng(8) == 0 ? s : name + " && " + s;
       case p++:
         var name = getVarName();
-        return name + " && " + name + "." + getDotKey();
+        var s = name + "." + getDotKey();
+        return canThrow && rng(8) == 0 ? s : name + " && " + s;
+      case p++:
+      case p++:
+        var name = getVarName();
+        var s = name + "." + getDotKey();
+        s = "typeof " + s + ' == "function" && --_calls_ >= 0 && ' + s + "(" + createArgs(recurmax, stmtDepth, canThrow) + ")";
+        return canThrow && rng(8) == 0 ? s : name + " && " + s;
       case p++:
       case p++:
       case p++:
       case p++:
-        if (rng(16) == 0) {
-            var name = getVarName();
-            var fn = name + "." + getDotKey();
-            called[name] = true;
-            return name + " && " + "typeof " + fn + ' == "function" && --_calls_ >= 0 && ' + fn + "(" + createArgs(recurmax, stmtDepth, canThrow) + ")";
-        }
         var name = rng(3) == 0 ? getVarName() : "f" + rng(funcs + 2);
         called[name] = true;
         return "typeof " + name + ' == "function" && --_calls_ >= 0 && ' + name + "(" + createArgs(recurmax, stmtDepth, canThrow) + ")";
@@ -1018,7 +1020,7 @@ function log_suspects(minify_options, component) {
     var defs = default_options[component];
     var suspects = Object.keys(defs).filter(function(name) {
         var flip = name == "keep_fargs";
-        if (flip === !(name in options ? options : defs)[name]) {
+        if (flip !== (name in options ? options : defs)[name]) {
             var m = JSON.parse(JSON.stringify(minify_options));
             var o = JSON.parse(JSON.stringify(options));
             o[name] = flip;
@@ -1029,7 +1031,7 @@ function log_suspects(minify_options, component) {
                 errorln(result.error);
             } else {
                 var r = sandbox.run_code(result.code, sandbox.has_toplevel(m));
-                return sandbox.same_stdout(original_result, r);
+                return !sandbox.same_stdout(uglify_result, r);
             }
         }
     });
@@ -1043,10 +1045,8 @@ function log_suspects(minify_options, component) {
 }
 
 function log_suspects_global(options) {
-    var o = {};
-    UglifyJS.minify("", o);
-    var suspects = Object.keys(o).filter(function(component) {
-      return typeof o[component] != "object";
+    var suspects = Object.keys(default_options).filter(function(component) {
+      return typeof default_options[component] != "object";
     }).filter(function(component) {
         var m = JSON.parse(options);
         m[component] = false;
@@ -1056,7 +1056,7 @@ function log_suspects_global(options) {
             errorln(result.error);
         } else {
             var r = sandbox.run_code(result.code, sandbox.has_toplevel(m));
-            return sandbox.same_stdout(original_result, r);
+            return !sandbox.same_stdout(uglify_result, r);
         }
     });
     if (suspects.length > 0) {
@@ -1113,7 +1113,10 @@ function log(options) {
     errorln(JSON.stringify(JSON.parse(options), null, 2));
     errorln();
     if (!ok && typeof uglify_code == "string") {
-        Object.keys(default_options).forEach(log_suspects.bind(null, JSON.parse(options)));
+        Object.keys(default_options).filter(function(component) {
+          var defs = default_options[component];
+          return defs && typeof defs == "object";
+        }).forEach(log_suspects.bind(null, JSON.parse(options)));
         log_suspects_global(options);
         errorln("!!!!!! Failed... round " + round);
     }
@@ -1133,11 +1136,50 @@ function fuzzy_match(original, uglified) {
     return true;
 }
 
+function skip_infinite_recursion(orig, toplevel) {
+    var code = orig;
+    var tries = [];
+    var offset = 0;
+    var re = /(?:(?:^|[\s{};])try|}\s*catch\s*\(([^)]+)\)|}\s*finally)\s*(?={)/g;
+    var match;
+    while (match = re.exec(code)) {
+        if (/}\s*finally\s*$/.test(match[0])) {
+            tries.shift();
+            continue;
+        }
+        if (tries.length && tries[0].catch) tries.shift();
+        var index = match.index + match[0].length + 1;
+        if (/(?:^|[\s{};])try\s*$/.test(match[0])) {
+            tries.unshift({ try: index - offset });
+            continue;
+        }
+        tries[0].catch = index;
+        var insert = "throw " + match[1] + ".ufuzz_skip || (" + match[1] + ".ufuzz_skip = " + tries[0].try + "), " + match[1] + ";";
+        var new_code = code.slice(0, index) + insert + code.slice(index);
+        var result = sandbox.run_code(new_code, toplevel);
+        if (typeof result != "object" || typeof result.name != "string" || typeof result.message != "string") {
+            offset += insert.length;
+            code = new_code;
+        } else if (result.name == "RangeError" && result.message == "Maximum call stack size exceeded") {
+            index = result.ufuzz_skip;
+            return orig.slice(0, index) + 'throw new Error("skipping infinite recursion");' + orig.slice(index);
+        }
+    }
+}
+
 var fallback_options = [ JSON.stringify({
     compress: false,
     mangle: false
 }) ];
 var minify_options = require("./options.json").map(JSON.stringify);
+var sort_globals = [
+    "Object.keys(this).sort().forEach(function(name) {",
+    "    var value = this[name];",
+    "    delete this[name];",
+    "    this[name] = value;",
+    "});",
+    "",
+].join("\n");
 var original_code, original_result, errored;
 var uglify_code, uglify_result, ok;
 for (var round = 1; round <= num_iterations; round++) {
@@ -1150,24 +1192,36 @@ for (var round = 1; round <= num_iterations; round++) {
     (errored ? fallback_options : minify_options).forEach(function(options) {
         var o = JSON.parse(options);
         var toplevel = sandbox.has_toplevel(o);
+        o.validate = true;
         uglify_code = UglifyJS.minify(original_code, o);
         original_result = orig_result[toplevel ? 1 : 0];
         if (!uglify_code.error) {
             uglify_code = uglify_code.code;
             uglify_result = sandbox.run_code(uglify_code, toplevel);
             ok = sandbox.same_stdout(original_result, uglify_result);
-            if (!ok && typeof uglify_result == "string" && o.compress.unsafe_math) {
+            // ignore declaration order of global variables
+            if (!ok && !toplevel) {
+                ok = sandbox.same_stdout(sandbox.run_code(sort_globals + original_code), sandbox.run_code(sort_globals + uglify_code));
+            }
+            // ignore numerical imprecision caused by `unsafe_math`
+            if (!ok && typeof uglify_result == "string" && o.compress && o.compress.unsafe_math) {
                 ok = fuzzy_match(original_result, uglify_result);
                 if (!ok) {
                     var fuzzy_result = sandbox.run_code(original_code.replace(/( - 0\.1){3}/g, " - 0.3"), toplevel);
                     ok = sandbox.same_stdout(fuzzy_result, uglify_result);
                 }
             }
+            // ignore difference in depth of termination caused by infinite recursion
+            if (!ok) {
+                var orig_skipped = skip_infinite_recursion(original_code, toplevel);
+                var uglify_skipped = skip_infinite_recursion(uglify_code, toplevel);
+                if (orig_skipped && uglify_skipped) {
+                    ok = sandbox.same_stdout(sandbox.run_code(orig_skipped, toplevel), sandbox.run_code(uglify_skipped, toplevel));
+                }
+            }
         } else {
             uglify_code = uglify_code.error;
-            if (errored) {
-                ok = uglify_code.name == original_result.name;
-            }
+            ok = errored && uglify_code.name == original_result.name;
         }
         if (verbose || (verbose_interval && !(round % INTERVAL_COUNT)) || !ok) log(options);
         else if (errored) {

tools/node.js

@@ -66,8 +66,8 @@ function infer_options(options) {
 }
 
 exports.default_options = function() {
-    var defs = {};
-    Object.keys(infer_options({ 0: 0 })).forEach(function(component) {
+    var defs = infer_options({ 0: 0 });
+    Object.keys(defs).forEach(function(component) {
         var options = {};
         options[component] = { 0: 0 };
         if (options = infer_options(options)) {