v3.11.0

fixes #4155

.github/workflows/ufuzz.yml

@@ -6,6 +6,7 @@ on:
 env:
   BASE_URL: https://api.github.com/repos/${{ github.repository }}
   CAUSE: ${{ github.event_name }}
+  RUN_NUM: ${{ github.run_number }}
   TOKEN: ${{ github.token }}
 jobs:
   ufuzz:
@@ -36,12 +37,8 @@ jobs:
           npm config set update-notifier false
           npm --version
           while !(npm install); do echo "'npm install' failed - retrying..."; done
-          PERIOD=1800000
           if [[ $CAUSE == "schedule" ]]; then
-            PERIOD=`node test/ufuzz/actions $BASE_URL $TOKEN`
-          fi
-          if (( $PERIOD == 0 )); then
-            echo "too many jobs in queue - skipping..."
+            node test/ufuzz/job $BASE_URL $TOKEN $RUN_NUM
           else
-            node test/ufuzz/job $PERIOD
+            node test/ufuzz/job 5000
           fi

README.md

@@ -688,6 +688,8 @@ to be `false` and all symbol names will be omitted.
 - `loops` (default: `true`) -- optimizations for `do`, `while` and `for` loops
   when we can statically determine the condition.
 
+- `merge_vars` (default: `true`) -- combine and reuse variables.
+
 - `negate_iife` (default: `true`) -- negate "Immediately-Called Function Expressions"
   where the return value is discarded, to avoid the parens that the
   code generator would insert.

lib/ast.js

@@ -288,10 +288,13 @@ var AST_LabeledStatement = DEFNODE("LabeledStatement", "label", {
             var label = node.label;
             var def = this.label;
             node.walk(new TreeWalker(function(node) {
-                if (node instanceof AST_LoopControl && node.label && node.label.thedef === def) {
+                if (node instanceof AST_LoopControl) {
+                    if (!node.label || node.label.thedef !== def) return;
                     node.label.thedef = label;
                     label.references.push(node);
+                    return true;
                 }
+                if (node instanceof AST_Scope) return true;
             }));
         }
         return node;
@@ -409,16 +412,16 @@ var AST_With = DEFNODE("With", "expression", {
 
 /* -----[ scope and functions ]----- */
 
-var AST_Scope = DEFNODE("Scope", "variables functions uses_with uses_eval parent_scope enclosed cname", {
+var AST_Scope = DEFNODE("Scope", "cname enclosed uses_eval uses_with parent_scope functions variables make_def", {
     $documentation: "Base class for all statements introducing a lexical scope",
     $propdoc: {
-        variables: "[Object/S] a map of name -> SymbolDef for all variables/functions defined in this scope",
-        functions: "[Object/S] like `variables`, but only lists function declarations",
-        uses_with: "[boolean/S] tells whether this scope uses the `with` statement",
-        uses_eval: "[boolean/S] tells whether this scope contains a direct call to the global `eval`",
-        parent_scope: "[AST_Scope?/S] link to the parent scope",
-        enclosed: "[SymbolDef*/S] a list of all symbol definitions that are accessed from this scope or any subscopes",
         cname: "[integer/S] current index for mangling variables (used internally by the mangler)",
+        enclosed: "[SymbolDef*/S] a list of all symbol definitions that are accessed from this scope or any subscopes",
+        uses_eval: "[boolean/S] tells whether this scope contains a direct call to the global `eval`",
+        uses_with: "[boolean/S] tells whether this scope uses the `with` statement",
+        parent_scope: "[AST_Scope?/S] link to the parent scope",
+        functions: "[Object/S] like `variables`, but only lists function declarations",
+        variables: "[Object/S] a map of name -> SymbolDef for all variables/functions defined in this scope",
     },
     clone: function(deep) {
         var node = this._clone(deep);
@@ -628,6 +631,9 @@ var AST_Switch = DEFNODE("Switch", "expression", {
     },
     _validate: function() {
         must_be_expression(this, "expression");
+        this.body.forEach(function(node) {
+            if (!(node instanceof AST_SwitchBranch)) throw new Error("body must be AST_SwitchBranch[]");
+        });
     },
 }, AST_Block);
 

lib/output.js

@@ -100,7 +100,7 @@ function OutputStream(options) {
         }
     }
 
-    var indentation = 0;
+    var indentation = options.indent_start;
     var current_col = 0;
     var current_line = 1;
     var current_pos = 0;
@@ -191,10 +191,6 @@ function OutputStream(options) {
         return name;
     }
 
-    function make_indent(back) {
-        return repeat_string(" ", options.indent_start + indentation - back * options.indent_level);
-    }
-
     /* -----[ beautification/minification ]----- */
 
     var has_parens = false;
@@ -345,9 +341,7 @@ function OutputStream(options) {
     };
 
     var indent = options.beautify ? function(half) {
-        if (options.beautify) {
-            print(make_indent(half ? 0.5 : 0));
-        }
+        print(repeat_string(" ", half ? indentation - (options.indent_level >> 1) : indentation));
     } : noop;
 
     var with_indent = options.beautify ? function(col, cont) {
@@ -575,9 +569,9 @@ function OutputStream(options) {
         get             : get,
         toString        : get,
         indent          : indent,
-        indentation     : function() { return indentation },
-        current_width   : function() { return current_col - indentation },
-        should_break    : function() { return options.width && this.current_width() >= options.width },
+        should_break    : readonly ? noop : function() {
+            return options.width && current_col - indentation >= options.width;
+        },
         has_parens      : function() { return has_parens },
         newline         : newline,
         print           : print,
@@ -630,13 +624,7 @@ function OutputStream(options) {
     var use_asm = false;
 
     AST_Node.DEFMETHOD("print", function(stream, force_parens) {
-        var self = this, generator = self._codegen;
-        function doit() {
-            stream.prepend_comments(self);
-            self.add_source_map(stream);
-            generator(self, stream);
-            stream.append_comments(self);
-        }
+        var self = this;
         stream.push_node(self);
         if (force_parens || self.needs_parens(stream)) {
             stream.with_parens(doit);
@@ -644,9 +632,14 @@ function OutputStream(options) {
             doit();
         }
         stream.pop_node();
-    });
-    AST_Node.DEFMETHOD("_print", AST_Node.prototype.print);
 
+        function doit() {
+            stream.prepend_comments(self);
+            self.add_source_map(stream);
+            self._codegen(stream);
+            stream.append_comments(self);
+        }
+    });
     AST_Node.DEFMETHOD("print_to_string", function(options) {
         var s = OutputStream(options);
         this.print(s);
@@ -689,78 +682,66 @@ function OutputStream(options) {
 
     PARENS(AST_Unary, function(output) {
         var p = output.parent();
-        return p instanceof AST_PropAccess && p.expression === this
-            || p instanceof AST_Call && p.expression === this;
+        return (p instanceof AST_Call || p instanceof AST_PropAccess) && p.expression === this;
     });
 
     PARENS(AST_Sequence, function(output) {
         var p = output.parent();
-            // (foo, bar)() or foo(1, (2, 3), 4)
-        return p instanceof AST_Call
-            // !(foo, bar, baz)
-            || p instanceof AST_Unary
+            // [ 1, (2, 3), 4 ] ==> [ 1, 3, 4 ]
+        return p instanceof AST_Array
             // 1 + (2, 3) + 4 ==> 8
             || p instanceof AST_Binary
-            // var a = (1, 2), b = a + a; ==> b == 4
-            || p instanceof AST_VarDef
-            // (1, {foo:2}).foo or (1, {foo:2})["foo"] ==> 2
-            || p instanceof AST_PropAccess && p.expression === this
-            // [ 1, (2, 3), 4 ] ==> [ 1, 3, 4 ]
-            || p instanceof AST_Array
-            // { foo: (1, 2) }.foo ==> 2
-            || p instanceof AST_ObjectProperty
+            // new (foo, bar) or foo(1, (2, 3), 4)
+            || p instanceof AST_Call
             // (false, true) ? (a = 10, b = 20) : (c = 30)
             // ==> 20 (side effect, set a := 10 and b := 20)
-            || p instanceof AST_Conditional;
+            || p instanceof AST_Conditional
+            // { foo: (1, 2) }.foo ==> 2
+            || p instanceof AST_ObjectProperty
+            // (1, {foo:2}).foo or (1, {foo:2})["foo"] ==> 2
+            || p instanceof AST_PropAccess && p.expression === this
+            // !(foo, bar, baz)
+            || p instanceof AST_Unary
+            // var a = (1, 2), b = a + a; ==> b == 4
+            || p instanceof AST_VarDef;
     });
 
     PARENS(AST_Binary, function(output) {
         var p = output.parent();
-        // (foo && bar)()
-        if (p instanceof AST_Call && p.expression === this)
-            return true;
-        // typeof (foo && bar)
-        if (p instanceof AST_Unary)
-            return true;
-        // (foo && bar)["prop"], (foo && bar).prop
-        if (p instanceof AST_PropAccess && p.expression === this)
-            return true;
         // this deals with precedence: 3 * (2 + 1)
         if (p instanceof AST_Binary) {
             var po = p.operator, pp = PRECEDENCE[po];
             var so = this.operator, sp = PRECEDENCE[so];
-            if (pp > sp
-                || (pp == sp
-                    && this === p.right)) {
-                return true;
-            }
+            return pp > sp || (pp == sp && this === p.right);
         }
+        // (foo && bar)()
+        if (p instanceof AST_Call) return p.expression === this;
+        // (foo && bar)["prop"], (foo && bar).prop
+        if (p instanceof AST_PropAccess) return p.expression === this;
+        // typeof (foo && bar)
+        if (p instanceof AST_Unary) return true;
     });
 
     PARENS(AST_PropAccess, function(output) {
+        var node = this;
         var p = output.parent();
-        if (p instanceof AST_New && p.expression === this) {
-            // i.e. new (foo.bar().baz)
+        if (p instanceof AST_New && p.expression === node) {
+            // i.e. new (foo().bar)
             //
             // if there's one call into this subtree, then we need
             // parens around it too, otherwise the call will be
             // interpreted as passing the arguments to the upper New
             // expression.
-            var parens = false;
-            this.walk(new TreeWalker(function(node) {
-                if (parens || node instanceof AST_Scope) return true;
-                if (node instanceof AST_Call) {
-                    parens = true;
-                    return true;
-                }
-            }));
-            return parens;
+            do {
+                node = node.expression;
+            } while (node instanceof AST_PropAccess);
+            return node.TYPE == "Call";
         }
     });
 
     PARENS(AST_Call, function(output) {
         var p = output.parent();
-        if (p instanceof AST_New && p.expression === this) return true;
+        if (p instanceof AST_New) return p.expression === this;
         // https://bugs.webkit.org/show_bug.cgi?id=123506
         if (output.option('webkit')) {
             var g = output.parent(1);
@@ -773,11 +754,12 @@ function OutputStream(options) {
     });
 
     PARENS(AST_New, function(output) {
+        if (need_constructor_parens(this, output)) return false;
         var p = output.parent();
-        if (!need_constructor_parens(this, output)
-            && (p instanceof AST_PropAccess // (new Date).getTime(), (new Date)["getTime"]()
-                || p instanceof AST_Call && p.expression === this)) // (new foo)(bar)
-            return true;
+        // (new foo)(bar)
+        if (p instanceof AST_Call) return p.expression === this;
+        // (new Date).getTime(), (new Date)["getTime"]()
+        return p instanceof AST_PropAccess;
     });
 
     PARENS(AST_Number, function(output) {
@@ -786,36 +768,29 @@ function OutputStream(options) {
             var value = this.value;
             // https://github.com/mishoo/UglifyJS/issues/115
             // https://github.com/mishoo/UglifyJS/pull/1009
-            if (value < 0 || /^0/.test(make_num(value))) {
-                return true;
-            }
+            return value < 0 || /^0/.test(make_num(value));
         }
     });
 
     PARENS([ AST_Assign, AST_Conditional ], function(output) {
         var p = output.parent();
-        // !(a = false) → true
-        if (p instanceof AST_Unary)
-            return true;
         // 1 + (a = 2) + 3 → 6, side effect setting a = 2
-        if (p instanceof AST_Binary && !(p instanceof AST_Assign))
-            return true;
+        if (p instanceof AST_Binary) return !(p instanceof AST_Assign);
         // (a = func)() —or— new (a = Object)()
-        if (p instanceof AST_Call && p.expression === this)
-            return true;
+        if (p instanceof AST_Call) return p.expression === this;
         // (a = foo) ? bar : baz
-        if (p instanceof AST_Conditional && p.condition === this)
-            return true;
+        if (p instanceof AST_Conditional) return p.condition === this;
         // (a = foo)["prop"] —or— (a = foo).prop
-        if (p instanceof AST_PropAccess && p.expression === this)
-            return true;
+        if (p instanceof AST_PropAccess) return p.expression === this;
+        // !(a = false) → true
+        if (p instanceof AST_Unary) return true;
     });
 
     /* -----[ PRINTERS ]----- */
 
-    DEFPRINT(AST_Directive, function(self, output) {
-        var quote = self.quote;
-        var value = self.value;
+    DEFPRINT(AST_Directive, function(output) {
+        var quote = this.quote;
+        var value = this.value;
         switch (output.option("quote_style")) {
           case 0:
           case 2:
@@ -828,7 +803,7 @@ function OutputStream(options) {
         output.print(quote + value + quote);
         output.semicolon();
     });
-    DEFPRINT(AST_Debugger, function(self, output) {
+    DEFPRINT(AST_Debugger, function(output) {
         output.print("debugger");
         output.semicolon();
     });
@@ -864,21 +839,21 @@ function OutputStream(options) {
         force_statement(this.body, output);
     });
 
-    DEFPRINT(AST_Statement, function(self, output) {
-        self.body.print(output);
+    DEFPRINT(AST_Statement, function(output) {
+        this.body.print(output);
         output.semicolon();
     });
-    DEFPRINT(AST_Toplevel, function(self, output) {
-        display_body(self.body, true, output, true);
+    DEFPRINT(AST_Toplevel, function(output) {
+        display_body(this.body, true, output, true);
         output.print("");
     });
-    DEFPRINT(AST_LabeledStatement, function(self, output) {
-        self.label.print(output);
+    DEFPRINT(AST_LabeledStatement, function(output) {
+        this.label.print(output);
         output.colon();
-        self.body.print(output);
+        this.body.print(output);
     });
-    DEFPRINT(AST_SimpleStatement, function(self, output) {
-        self.body.print(output);
+    DEFPRINT(AST_SimpleStatement, function(output) {
+        this.body.print(output);
         output.semicolon();
     });
     function print_braced_empty(self, output) {
@@ -895,13 +870,14 @@ function OutputStream(options) {
             });
         } else print_braced_empty(self, output);
     }
-    DEFPRINT(AST_BlockStatement, function(self, output) {
-        print_braced(self, output);
+    DEFPRINT(AST_BlockStatement, function(output) {
+        print_braced(this, output);
     });
-    DEFPRINT(AST_EmptyStatement, function(self, output) {
+    DEFPRINT(AST_EmptyStatement, function(output) {
         output.semicolon();
     });
-    DEFPRINT(AST_Do, function(self, output) {
+    DEFPRINT(AST_Do, function(output) {
+        var self = this;
         output.print("do");
         output.space();
         make_block(self.body, output);
@@ -913,7 +889,8 @@ function OutputStream(options) {
         });
         output.semicolon();
     });
-    DEFPRINT(AST_While, function(self, output) {
+    DEFPRINT(AST_While, function(output) {
+        var self = this;
         output.print("while");
         output.space();
         output.with_parens(function() {
@@ -922,7 +899,8 @@ function OutputStream(options) {
         output.space();
         self._do_print_body(output);
     });
-    DEFPRINT(AST_For, function(self, output) {
+    DEFPRINT(AST_For, function(output) {
+        var self = this;
         output.print("for");
         output.space();
         output.with_parens(function() {
@@ -951,7 +929,8 @@ function OutputStream(options) {
         output.space();
         self._do_print_body(output);
     });
-    DEFPRINT(AST_ForIn, function(self, output) {
+    DEFPRINT(AST_ForIn, function(output) {
+        var self = this;
         output.print("for");
         output.space();
         output.with_parens(function() {
@@ -964,7 +943,8 @@ function OutputStream(options) {
         output.space();
         self._do_print_body(output);
     });
-    DEFPRINT(AST_With, function(self, output) {
+    DEFPRINT(AST_With, function(output) {
+        var self = this;
         output.print("with");
         output.space();
         output.with_parens(function() {
@@ -975,7 +955,7 @@ function OutputStream(options) {
     });
 
     /* -----[ functions ]----- */
-    AST_Lambda.DEFMETHOD("_do_print", function(output, nokeyword) {
+    DEFPRINT(AST_Lambda, function(output, nokeyword) {
         var self = this;
         if (!nokeyword) {
             output.print("function");
@@ -993,32 +973,23 @@ function OutputStream(options) {
         output.space();
         print_braced(self, output, true);
     });
-    DEFPRINT(AST_Lambda, function(self, output) {
-        self._do_print(output);
-    });
 
     /* -----[ jumps ]----- */
-    function print_jump(output, kind, target) {
-        output.print(kind);
-        if (target) {
-            output.space();
-            target.print(output);
-        }
-        output.semicolon();
+    function print_jump(kind, prop) {
+        return function(output) {
+            output.print(kind);
+            var target = this[prop];
+            if (target) {
+                output.space();
+                target.print(output);
+            }
+            output.semicolon();
+        };
     }
-
-    DEFPRINT(AST_Return, function(self, output) {
-        print_jump(output, "return", self.value);
-    });
-    DEFPRINT(AST_Throw, function(self, output) {
-        print_jump(output, "throw", self.value);
-    });
-    DEFPRINT(AST_Break, function(self, output) {
-        print_jump(output, "break", self.label);
-    });
-    DEFPRINT(AST_Continue, function(self, output) {
-        print_jump(output, "continue", self.label);
-    });
+    DEFPRINT(AST_Return, print_jump("return", "value"));
+    DEFPRINT(AST_Throw, print_jump("throw", "value"));
+    DEFPRINT(AST_Break, print_jump("break", "label"));
+    DEFPRINT(AST_Continue, print_jump("continue", "label"));
 
     /* -----[ if ]----- */
     function make_then(self, output) {
@@ -1047,7 +1018,8 @@ function OutputStream(options) {
         }
         force_statement(self.body, output);
     }
-    DEFPRINT(AST_If, function(self, output) {
+    DEFPRINT(AST_If, function(output) {
+        var self = this;
         output.print("if");
         output.space();
         output.with_parens(function() {
@@ -1069,7 +1041,8 @@ function OutputStream(options) {
     });
 
     /* -----[ switch ]----- */
-    DEFPRINT(AST_Switch, function(self, output) {
+    DEFPRINT(AST_Switch, function(output) {
+        var self = this;
         output.print("switch");
         output.space();
         output.with_parens(function() {
@@ -1087,28 +1060,30 @@ function OutputStream(options) {
             });
         });
     });
-    AST_SwitchBranch.DEFMETHOD("_do_print_body", function(output) {
+    function print_branch_body(self, output) {
         output.newline();
-        this.body.forEach(function(stmt) {
+        self.body.forEach(function(stmt) {
             output.indent();
             stmt.print(output);
             output.newline();
         });
-    });
-    DEFPRINT(AST_Default, function(self, output) {
+    }
+    DEFPRINT(AST_Default, function(output) {
         output.print("default:");
-        self._do_print_body(output);
+        print_branch_body(this, output);
     });
-    DEFPRINT(AST_Case, function(self, output) {
+    DEFPRINT(AST_Case, function(output) {
+        var self = this;
         output.print("case");
         output.space();
         self.expression.print(output);
         output.print(":");
-        self._do_print_body(output);
+        print_branch_body(self, output);
     });
 
     /* -----[ exceptions ]----- */
-    DEFPRINT(AST_Try, function(self, output) {
+    DEFPRINT(AST_Try, function(output) {
+        var self = this;
         output.print("try");
         output.space();
         print_braced(self, output);
@@ -1121,7 +1096,8 @@ function OutputStream(options) {
             self.bfinally.print(output);
         }
     });
-    DEFPRINT(AST_Catch, function(self, output) {
+    DEFPRINT(AST_Catch, function(output) {
+        var self = this;
         output.print("catch");
         output.space();
         output.with_parens(function() {
@@ -1130,13 +1106,14 @@ function OutputStream(options) {
         output.space();
         print_braced(self, output);
     });
-    DEFPRINT(AST_Finally, function(self, output) {
+    DEFPRINT(AST_Finally, function(output) {
         output.print("finally");
         output.space();
-        print_braced(self, output);
+        print_braced(this, output);
     });
 
-    DEFPRINT(AST_Var, function(self, output) {
+    DEFPRINT(AST_Var, function(output) {
+        var self = this;
         output.print("var");
         output.space();
         self.definitions.forEach(function(def, i) {
@@ -1161,7 +1138,8 @@ function OutputStream(options) {
         node.print(output, parens);
     }
 
-    DEFPRINT(AST_VarDef, function(self, output) {
+    DEFPRINT(AST_VarDef, function(output) {
+        var self = this;
         self.name.print(output);
         if (self.value) {
             output.space();
@@ -1185,18 +1163,19 @@ function OutputStream(options) {
             });
         });
     }
-    DEFPRINT(AST_Call, function(self, output) {
-        self.expression.print(output);
-        print_call_args(self, output);
+    DEFPRINT(AST_Call, function(output) {
+        this.expression.print(output);
+        print_call_args(this, output);
     });
-    DEFPRINT(AST_New, function(self, output) {
+    DEFPRINT(AST_New, function(output) {
+        var self = this;
         output.print("new");
         output.space();
         self.expression.print(output);
         if (need_constructor_parens(self, output)) print_call_args(self, output);
     });
-    DEFPRINT(AST_Sequence, function(self, output) {
-        self.expressions.forEach(function(node, index) {
+    DEFPRINT(AST_Sequence, function(output) {
+        this.expressions.forEach(function(node, index) {
             if (index > 0) {
                 output.comma();
                 if (output.should_break()) {
@@ -1207,7 +1186,8 @@ function OutputStream(options) {
             node.print(output);
         });
     });
-    DEFPRINT(AST_Dot, function(self, output) {
+    DEFPRINT(AST_Dot, function(output) {
+        var self = this;
         var expr = self.expression;
         expr.print(output);
         var prop = self.property;
@@ -1228,35 +1208,38 @@ function OutputStream(options) {
             output.print_name(prop);
         }
     });
-    DEFPRINT(AST_Sub, function(self, output) {
-        self.expression.print(output);
+    DEFPRINT(AST_Sub, function(output) {
+        this.expression.print(output);
         output.print("[");
-        self.property.print(output);
+        this.property.print(output);
         output.print("]");
     });
-    DEFPRINT(AST_UnaryPrefix, function(self, output) {
-        var op = self.operator;
+    DEFPRINT(AST_UnaryPrefix, function(output) {
+        var op = this.operator;
+        var exp = this.expression;
         output.print(op);
         if (/^[a-z]/i.test(op)
             || (/[+-]$/.test(op)
-                && self.expression instanceof AST_UnaryPrefix
-                && /^[+-]/.test(self.expression.operator))) {
+                && exp instanceof AST_UnaryPrefix
+                && /^[+-]/.test(exp.operator))) {
             output.space();
         }
-        self.expression.print(output);
+        exp.print(output);
     });
-    DEFPRINT(AST_UnaryPostfix, function(self, output) {
-        self.expression.print(output);
-        output.print(self.operator);
+    DEFPRINT(AST_UnaryPostfix, function(output) {
+        this.expression.print(output);
+        output.print(this.operator);
     });
-    DEFPRINT(AST_Binary, function(self, output) {
+    DEFPRINT(AST_Binary, function(output) {
+        var self = this;
         self.left.print(output);
         output.space();
         output.print(self.operator);
         output.space();
         self.right.print(output);
     });
-    DEFPRINT(AST_Conditional, function(self, output) {
+    DEFPRINT(AST_Conditional, function(output) {
+        var self = this;
         self.condition.print(output);
         output.space();
         output.print("?");
@@ -1268,10 +1251,10 @@ function OutputStream(options) {
     });
 
     /* -----[ literals ]----- */
-    DEFPRINT(AST_Array, function(self, output) {
-        output.with_square(function() {
-            var a = self.elements, len = a.length;
-            if (len > 0) output.space();
+    DEFPRINT(AST_Array, function(output) {
+        var a = this.elements, len = a.length;
+        output.with_square(len > 0 ? function() {
+            output.space();
             a.forEach(function(exp, i) {
                 if (i) output.comma();
                 exp.print(output);
@@ -1281,12 +1264,13 @@ function OutputStream(options) {
                 if (i === len - 1 && exp instanceof AST_Hole)
                   output.comma();
             });
-            if (len > 0) output.space();
-        });
+            output.space();
+        } : noop);
     });
-    DEFPRINT(AST_Object, function(self, output) {
-        if (self.properties.length > 0) output.with_block(function() {
-            self.properties.forEach(function(prop, i) {
+    DEFPRINT(AST_Object, function(output) {
+        var props = this.properties;
+        if (props.length > 0) output.with_block(function() {
+            props.forEach(function(prop, i) {
                 if (i) {
                     output.print(",");
                     output.newline();
@@ -1296,7 +1280,7 @@ function OutputStream(options) {
             });
             output.newline();
         });
-        else print_braced_empty(self, output);
+        else print_braced_empty(this, output);
     });
 
     function print_property_name(key, quote, output) {
@@ -1315,47 +1299,48 @@ function OutputStream(options) {
         }
     }
 
-    DEFPRINT(AST_ObjectKeyVal, function(self, output) {
+    DEFPRINT(AST_ObjectKeyVal, function(output) {
+        var self = this;
         print_property_name(self.key, self.quote, output);
         output.colon();
         self.value.print(output);
     });
-    AST_ObjectProperty.DEFMETHOD("_print_getter_setter", function(type, output) {
-        output.print(type);
-        output.space();
-        print_property_name(this.key.name, this.quote, output);
-        this.value._do_print(output, true);
-    });
-    DEFPRINT(AST_ObjectSetter, function(self, output) {
-        self._print_getter_setter("set", output);
-    });
-    DEFPRINT(AST_ObjectGetter, function(self, output) {
-        self._print_getter_setter("get", output);
-    });
-    DEFPRINT(AST_Symbol, function(self, output) {
-        var def = self.definition();
-        output.print_name(def && def.mangled_name || self.name);
+    function print_accessor(type) {
+        return function(output) {
+            var self = this;
+            output.print(type);
+            output.space();
+            print_property_name(self.key.name, self.quote, output);
+            self.value._codegen(output, true);
+        };
+    }
+    DEFPRINT(AST_ObjectGetter, print_accessor("get"));
+    DEFPRINT(AST_ObjectSetter, print_accessor("set"));
+    DEFPRINT(AST_Symbol, function(output) {
+        var def = this.definition();
+        output.print_name(def && def.mangled_name || this.name);
     });
     DEFPRINT(AST_Hole, noop);
-    DEFPRINT(AST_This, function(self, output) {
+    DEFPRINT(AST_This, function(output) {
         output.print("this");
     });
-    DEFPRINT(AST_Constant, function(self, output) {
-        output.print(self.value);
+    DEFPRINT(AST_Constant, function(output) {
+        output.print(this.value);
     });
-    DEFPRINT(AST_String, function(self, output) {
-        output.print_string(self.value, self.quote);
+    DEFPRINT(AST_String, function(output) {
+        output.print_string(this.value, this.quote);
     });
-    DEFPRINT(AST_Number, function(self, output) {
-        if (use_asm && self.start && self.start.raw != null) {
-            output.print(self.start.raw);
+    DEFPRINT(AST_Number, function(output) {
+        var start = this.start;
+        if (use_asm && start && start.raw != null) {
+            output.print(start.raw);
         } else {
-            output.print(make_num(self.value));
+            output.print(make_num(this.value));
         }
     });
 
-    DEFPRINT(AST_RegExp, function(self, output) {
-        var regexp = self.value;
+    DEFPRINT(AST_RegExp, function(output) {
+        var regexp = this.value;
         var str = regexp.toString();
         var end = str.lastIndexOf("/");
         if (regexp.raw_source) {
@@ -1389,7 +1374,7 @@ function OutputStream(options) {
             }
         }));
         var p = output.parent();
-        if (p instanceof AST_Binary && /^in/.test(p.operator) && p.left === self)
+        if (p instanceof AST_Binary && /^in/.test(p.operator) && p.left === this)
             output.print(" ");
     });
 

lib/parse.js

@@ -44,11 +44,14 @@
 
 "use strict";
 
-var KEYWORDS = 'break case catch const continue debugger default delete do else finally for function if in instanceof new return switch throw try typeof var void while with';
-var KEYWORDS_ATOM = 'false null true';
-var RESERVED_WORDS = 'abstract boolean byte char class double enum export extends final float goto implements import int interface let long native package private protected public short static super synchronized this throws transient volatile yield'
-    + " " + KEYWORDS_ATOM + " " + KEYWORDS;
-var KEYWORDS_BEFORE_EXPRESSION = 'return new delete throw else case';
+var KEYWORDS = "break case catch const continue debugger default delete do else finally for function if in instanceof new return switch throw try typeof var void while with";
+var KEYWORDS_ATOM = "false null true";
+var RESERVED_WORDS = [
+    "abstract boolean byte char class double enum export extends final float goto implements import int interface let long native package private protected public short static super synchronized this throws transient volatile yield",
+    KEYWORDS_ATOM,
+    KEYWORDS,
+].join(" ");
+var KEYWORDS_BEFORE_EXPRESSION = "return new delete throw else case";
 
 KEYWORDS = makePredicate(KEYWORDS);
 RESERVED_WORDS = makePredicate(RESERVED_WORDS);
@@ -438,7 +441,7 @@ function tokenizer($TEXT, filename, html5_comments, shebang) {
     var skip_multiline_comment = with_eof_error("Unterminated multiline comment", function() {
         var regex_allowed = S.regex_allowed;
         var i = find("*/", true);
-        var text = S.text.substring(S.pos, i).replace(/\r\n|\r|\u2028|\u2029/g, '\n');
+        var text = S.text.substring(S.pos, i).replace(/\r\n|\r|\u2028|\u2029/g, "\n");
         // update stream position
         forward(text.length /* doesn't count \r\n as 2 char while S.pos - i does */ + 2);
         S.comments_before.push(token("comment2", text, true));

lib/propmangle.js

@@ -110,7 +110,6 @@ function mangle_properties(ast, options) {
         cache: null,
         debug: false,
         keep_quoted: false,
-        only_cache: false,
         regex: null,
         reserved: null,
     }, true);
@@ -213,7 +212,6 @@ function mangle_properties(ast, options) {
 
     function can_mangle(name) {
         if (unmangleable[name]) return false;
-        if (options.only_cache) return cache.has(name);
         if (/^-?[0-9]+(\.[0-9]+)?(e[+-][0-9]+)?$/.test(name)) return false;
         return true;
     }

lib/scope.js

@@ -96,8 +96,9 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
 
     // pass 1: setup scope chaining and handle definitions
     var self = this;
-    var scope = self.parent_scope = null;
     var defun = null;
+    var next_def_id = 0;
+    var scope = self.parent_scope = null;
     var tw = new TreeWalker(function(node, descend) {
         if (node instanceof AST_Catch) {
             var save_scope = scope;
@@ -149,7 +150,9 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options) {
             scope.def_variable(node).defun = defun;
         }
     });
-    self.next_def_id = 0;
+    self.make_def = function(orig, init) {
+        return new SymbolDef(++next_def_id, this, orig, init);
+    };
     self.walk(tw);
 
     // pass 2: find back references and eval
@@ -240,12 +243,6 @@ 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)) {
@@ -259,24 +256,30 @@ AST_Toplevel.DEFMETHOD("def_global", function(node) {
     }
 });
 
+function init_scope_vars(scope, parent) {
+    scope.cname = -1;                               // the current index for mangling functions/variables
+    scope.enclosed = [];                            // variables from this or outer scope(s) that are referenced from this or inner scopes
+    scope.uses_eval = false;                        // will be set to true if this or nested scope uses the global `eval`
+    scope.uses_with = false;                        // will be set to true if this or some nested scope uses the `with` statement
+    scope.parent_scope = parent;                    // the parent scope (null if this is the top level)
+    scope.functions = new Dictionary();             // map name to AST_SymbolDefun (functions defined in this scope)
+    scope.variables = new Dictionary();             // map name to AST_SymbolVar (variables defined in this scope; includes functions)
+    if (parent) scope.make_def = parent.make_def;   // top-level tracking of SymbolDef instances
+}
+
 AST_Scope.DEFMETHOD("init_scope_vars", function(parent_scope) {
-    this.variables = new Dictionary();  // map name to AST_SymbolVar (variables defined in this scope; includes functions)
-    this.functions = new Dictionary();  // map name to AST_SymbolDefun (functions defined in this scope)
-    this.uses_with = false;             // will be set to true if this or some nested scope uses the `with` statement
-    this.uses_eval = false;             // will be set to true if this or nested scope uses the global `eval`
-    this.parent_scope = parent_scope;   // the parent scope
-    this.enclosed = [];                 // a list of variables from this or outer scope(s) that are referenced from this or inner scopes
-    this.cname = -1;                    // the current index for mangling functions/variables
+    init_scope_vars(this, parent_scope);
 });
 
-AST_Lambda.DEFMETHOD("init_scope_vars", function() {
-    AST_Scope.prototype.init_scope_vars.apply(this, arguments);
+AST_Lambda.DEFMETHOD("init_scope_vars", function(parent_scope) {
+    init_scope_vars(this, parent_scope);
     this.uses_arguments = false;
     this.def_variable(new AST_SymbolFunarg({
         name: "arguments",
         start: this.start,
-        end: this.end
+        end: this.end,
     }));
+    return this;
 });
 
 AST_Symbol.DEFMETHOD("mark_enclosed", function(options) {
@@ -332,7 +335,7 @@ AST_Toplevel.DEFMETHOD("resolve", return_this);
 function names_in_use(scope, options) {
     var names = scope.names_in_use;
     if (!names) {
-        scope.names_in_use = names = Object.create(scope.mangled_names || null);
+        scope.names_in_use = names = Object.create(null);
         scope.cname_holes = [];
         var cache = options.cache && options.cache.props;
         scope.enclosed.forEach(function(def) {
@@ -366,7 +369,7 @@ function next_mangled_name(scope, options, def) {
         name = base54(holes[i]);
         if (names[name]) continue;
         holes.splice(i, 1);
-        scope.names_in_use[name] = true;
+        in_use[name] = true;
         return name;
     }
     while (true) {
@@ -375,7 +378,7 @@ function next_mangled_name(scope, options, def) {
         if (!names[name]) break;
         holes.push(scope.cname);
     }
-    scope.names_in_use[name] = true;
+    in_use[name] = true;
     return name;
 }
 
@@ -387,18 +390,10 @@ AST_Symbol.DEFMETHOD("unmangleable", function(options) {
 // labels are always mangleable
 AST_Label.DEFMETHOD("unmangleable", return_false);
 
-AST_Symbol.DEFMETHOD("unreferenced", function() {
-    return !this.definition().references.length && !this.scope.pinned();
-});
-
 AST_Symbol.DEFMETHOD("definition", function() {
     return this.thedef;
 });
 
-AST_Symbol.DEFMETHOD("global", function() {
-    return this.definition().global;
-});
-
 function _default_mangler_options(options) {
     options = defaults(options, {
         eval        : false,
@@ -424,7 +419,7 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
     var lname = -1;
 
     if (options.cache && options.cache.props) {
-        var mangled_names = this.mangled_names = Object.create(null);
+        var mangled_names = names_in_use(this, options);
         options.cache.props.each(function(mangled_name) {
             mangled_names[mangled_name] = true;
         });
@@ -496,7 +491,7 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options) {
 
 AST_Toplevel.DEFMETHOD("find_colliding_names", function(options) {
     var cache = options.cache && options.cache.props;
-    var avoid = Object.create(null);
+    var avoid = Object.create(RESERVED_WORDS);
     options.reserved.forEach(to_avoid);
     this.globals.each(add_def);
     this.walk(new TreeWalker(function(node) {
@@ -533,7 +528,7 @@ AST_Toplevel.DEFMETHOD("expand_names", function(options) {
         var name;
         do {
             name = base54(cname++);
-        } while (avoid[name] || RESERVED_WORDS[name]);
+        } while (avoid[name]);
         return name;
     }
 
@@ -558,8 +553,8 @@ AST_Sequence.DEFMETHOD("tail_node", function() {
 AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options) {
     options = _default_mangler_options(options);
     base54.reset();
+    var fn = AST_Symbol.prototype.add_source_map;
     try {
-        var fn = AST_Symbol.prototype.add_source_map;
         AST_Symbol.prototype.add_source_map = function() {
             if (!this.unmangleable(options)) base54.consider(this.name, -1);
         };

lib/utils.js

@@ -112,51 +112,29 @@ function return_this() { return this; }
 function return_null() { return null; }
 
 var List = (function() {
-    function List(a, f, backwards) {
-        var ret = [], top = [], i;
-        function doit() {
+    function List(a, f) {
+        var ret = [];
+        for (var i = 0; i < a.length; i++) {
             var val = f(a[i], i);
-            var is_last = val instanceof Last;
-            if (is_last) val = val.v;
-            if (val instanceof AtTop) {
-                val = val.v;
-                if (val instanceof Splice) {
-                    top.push.apply(top, backwards ? val.v.slice().reverse() : val.v);
-                } else {
-                    top.push(val);
-                }
-            } else if (val !== skip) {
-                if (val instanceof Splice) {
-                    ret.push.apply(ret, backwards ? val.v.slice().reverse() : val.v);
-                } else {
-                    ret.push(val);
-                }
-            }
-            return is_last;
-        }
-        if (Array.isArray(a)) {
-            if (backwards) {
-                for (i = a.length; --i >= 0;) if (doit()) break;
-                ret.reverse();
-                top.reverse();
+            if (val === skip) continue;
+            if (val instanceof Splice) {
+                ret.push.apply(ret, val.v);
             } else {
-                for (i = 0; i < a.length; ++i) if (doit()) break;
+                ret.push(val);
             }
-        } else {
-            for (i in a) if (HOP(a, i)) if (doit()) break;
         }
-        return top.concat(ret);
+        return ret;
     }
     List.is_op = function(val) {
-        return val === skip || val instanceof AtTop || val instanceof Last || val instanceof Splice;
+        return val === skip || val instanceof Splice;
+    };
+    List.splice = function(val) {
+        return new Splice(val);
     };
-    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); };
     var skip = List.skip = {};
-    function AtTop(val) { this.v = val; }
-    function Splice(val) { this.v = val; }
-    function Last(val) { this.v = val; }
+    function Splice(val) {
+        this.v = val;
+    }
     return List;
 })();
 

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": "3.10.2",
+  "version": "3.11.0",
   "engines": {
     "node": ">=0.8.0"
   },

test/compress/asm.js

@@ -95,7 +95,7 @@ asm_mixed: {
                 return +sum;
             }
             function geometricMean(start, end) {
-                return start |= 0, end |= 0, +exp(logSum(start, end) / (end - start | 0));
+                return start |= 0, end |= 0, +exp(+logSum(start, end) / (end - start | 0));
             }
             var exp = stdlib.Math.exp, log = stdlib.Math.log, values = new stdlib.Float64Array(buffer);
             return { geometricMean: geometricMean };

test/compress/collapse_vars.js

@@ -62,18 +62,18 @@ collapse_vars_side_effects_1: {
     expect: {
         function f1() {
             var s = "abcdef", i = 2;
-            console.log.bind(console)(s.charAt(i++), s.charAt(i++), s.charAt(4), 7);
+            console.log.bind(console)(s.charAt(i++), s.charAt(+i), s.charAt(4), 7);
         }
         function f2() {
             var s = "abcdef", i = 2;
-            console.log.bind(console)(s.charAt(i++), 5, s.charAt(i++), s.charAt(i++), 7);
+            console.log.bind(console)(s.charAt(i++), 5, s.charAt(i++), s.charAt(+i), 7);
         }
         function f3() {
             var s = "abcdef",
                 i = 2,
                 log = console.log.bind(console),
                 x = s.charAt(i++),
-                y = s.charAt(i++);
+                y = s.charAt(+i);
             log(x, s.charAt(4), y, 7);
         }
         function f4() {
@@ -3073,7 +3073,6 @@ issue_2298: {
     expect: {
         !function() {
             (function() {
-                0;
                 try {
                     !function(b) {
                         (void 0)[1] = "foo";
@@ -8538,3 +8537,25 @@ issue_4051: {
     }
     expect_stdout: "undefined"
 }
+
+issue_4070: {
+    options = {
+        collapse_vars: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+    }
+    input: {
+        console.log(function f() {
+            function g() {}
+            g.p++;
+            return f.p = g.p;
+        }());
+    }
+    expect: {
+        console.log(function f() {
+            function g() {}
+            return f.p = ++g.p;
+        }());
+    }
+    expect_stdout: "NaN"
+}

test/compress/concat-strings.js

@@ -238,6 +238,41 @@ concat_8: {
     expect_stdout: true
 }
 
+concat_9: {
+    options = {
+        booleans: true,
+        evaluate: true,
+        reduce_vars: true,
+        strings: true,
+        toplevel: true,
+    }
+    input: {
+        var a = "foo";
+        console.log(
+            12 + (34 + a),
+            null + (34 + a),
+            12 + (null + a),
+            false + (34 + a),
+            12 + (false + a),
+            "bar" + (34 + a),
+            12 + ("bar" + a)
+        );
+    }
+    expect: {
+        var a = "foo";
+        console.log(
+            "1234" + a,
+            "null34" + a,
+            "12null" + a,
+            !1 + (34 + a),
+            12 + (!1 + a),
+            "bar34" + a,
+            "12bar" + a
+        );
+    }
+    expect_stdout: true
+}
+
 issue_3689: {
     options = {
         strings: true,

test/compress/conditionals.js

@@ -783,6 +783,28 @@ cond_12: {
     }
 }
 
+cond_13: {
+    options = {
+        conditionals: true,
+    }
+    input: {
+        x ? y(a) : z(a);
+        x ? y.f(a) : z.f(a);
+        x ? y.f(a) : z.g(a);
+        x ? y.f()(a) : z.g()(a);
+        x ? y.f.u(a) : z.g.u(a);
+        x ? y.f().u(a) : z.g().u(a);
+    }
+    expect: {
+        (x ? y : z)(a);
+        (x ? y : z).f(a);
+        x ? y.f(a) : z.g(a);
+        (x ? y.f() : z.g())(a);
+        (x ? y.f : z.g).u(a);
+        (x ? y.f() : z.g()).u(a);
+    }
+}
+
 ternary_boolean_consequent: {
     options = {
         booleans: true,

test/compress/drop-unused.js

@@ -1730,7 +1730,7 @@ chained_3: {
     expect: {
         console.log(function(a, b) {
             var c = b;
-            b++;
+            +b;
             return c;
         }(0, 2));
     }
@@ -1997,7 +1997,7 @@ issue_3146_4: {
     expect_stdout: "PASS"
 }
 
-issue_3192: {
+issue_3192_1: {
     options = {
         unused: true,
     }
@@ -2025,6 +2025,26 @@ issue_3192: {
     ]
 }
 
+issue_3192_2: {
+    options = {
+        keep_fargs: "strict",
+        unused: true,
+    }
+    input: {
+        "use strict";
+        (function(a) {
+            console.log(a = "foo", arguments[0]);
+        })("bar");
+    }
+    expect: {
+        "use strict";
+        (function() {
+            console.log("foo", arguments[0]);
+        })("bar");
+    }
+    expect_stdout: "foo bar"
+}
+
 issue_3233: {
     options = {
         pure_getters: "strict",
@@ -2161,8 +2181,7 @@ issue_3515_1: {
     expect: {
         var c = 0;
         (function() {
-            this[c++] = 0;
-            for (var key20 in !0);
+            for (var key20 in !(this[c++] = 0));
         })();
         console.log(c);
     }
@@ -2718,7 +2737,7 @@ issue_3962_1: {
                 0..toString();
             } while (0);
             if (c) console.log("PASS");
-        }((a--, 1)), 0);
+        }(1), 0);
         void 0;
     }
     expect_stdout: "PASS"
@@ -2751,7 +2770,7 @@ issue_3962_2: {
                 0..toString();
             } while (0);
             if (c) console.log("PASS");
-        }((a--, 1)), 0);
+        }(1), 0);
     }
     expect_stdout: "PASS"
 }
@@ -2834,11 +2853,11 @@ issue_4025: {
         console.log(a, b, d);
     }
     expect: {
-        var d, c = 0;
+        var c = 0;
         try {
             console.log(c);
         } finally {
-            d = c + 1;
+            var d = c + 1;
             c = 0;
         }
         console.log(1, 1, d);
@@ -2848,3 +2867,128 @@ issue_4025: {
         "1 1 1",
     ]
 }
+
+forin_var_1: {
+    options = {
+        unused: true,
+    }
+    input: {
+        var k;
+        for (k in [ 1, 2 ])
+            console.log(k);
+        for (k in { PASS: 3 })
+            console.log(k);
+        console.log(k);
+    }
+    expect: {
+        for (var k in [ 1, 2 ])
+            console.log(k);
+        for (k in { PASS: 3 })
+            console.log(k);
+        console.log(k);
+    }
+    expect_stdout: [
+        "0",
+        "1",
+        "PASS",
+        "PASS",
+    ]
+}
+
+forin_var_2: {
+    options = {
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            switch (0) {
+              case function() {
+                    for (a in 0);
+                }:
+                var b = 0;
+            }
+            for (var c = 0; a;);
+            var a;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            switch (0) {
+              case function() {
+                    for (a in 0);
+                }:
+            }
+            for (; a;);
+            var a;
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4133: {
+    options = {
+        evaluate: true,
+        merge_vars: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 1;
+        var b = [ a-- ], c = b && b[c];
+        console.log(a);
+    }
+    expect: {
+        var b = 1;
+        console.log(0);
+    }
+    expect_stdout: "0"
+}
+
+issue_4144: {
+    options = {
+        keep_fargs: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function(a, b) {
+            var b = console, c = ++b;
+        })(console.log("PASS"), 0);
+    }
+    expect: {
+        (function(b) {
+            b = console,
+            ++b;
+        })(console.log("PASS"));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4146: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f(a, b) {
+            function g() {}
+            var a = g;
+            var c = b;
+            c.p;
+            console.log(typeof a);
+        }
+        f("FAIL", 42);
+    }
+    expect: {
+        (function(a, b) {
+            a = function () {};
+            var c = b;
+            c.p;
+            console.log(typeof a);
+        })(0, 42);
+    }
+    expect_stdout: "function"
+}

test/compress/evaluate.js

@@ -2869,3 +2869,148 @@ issue_4035: {
         "true",
     ]
 }
+
+issue_4067: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+    }
+    input: {
+        (function(a) {
+            (function(b) {
+                b[0] += 0;
+                console.log(+a);
+            })(a);
+        })([]);
+    }
+    expect: {
+        (function(a) {
+            (function(b) {
+                b[0] += 0;
+                console.log(+a);
+            })(a);
+        })([]);
+    }
+    expect_stdout: "NaN"
+}
+
+issue_4077: {
+    options = {
+        evaluate: true,
+        unsafe: true,
+    }
+    input: {
+        console.log((a = []) - (a[0]++, 1) || "PASS");
+    }
+    expect: {
+        console.log((a = []) - (a[0]++, 1) || "PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4119_1: {
+    options = {
+        conditionals: true,
+        dead_code: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var a, b;
+        b = a = [];
+        a[0] += 0;
+        if (+b + 1) {
+            console.log("FAIL");
+        } else {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        var a, b;
+        b = a = [];
+        a[0] += 0;
+        +b + 1 ? console.log("FAIL") : console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4119_2: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+    }
+    input: {
+        var a;
+        (function(b) {
+            a[0] += 0;
+            console.log(+b + 1 ? "FAIL" : "PASS");
+        })(a = []);
+    }
+    expect: {
+        var a;
+        (function(b) {
+            a[0] += 0;
+            console.log(+b + 1 ? "FAIL" : "PASS");
+        })(a = []);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4119_3: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var a, b;
+        b = a = {
+            p: 42,
+        };
+        delete a.p;
+        console.log(b.p ? "FAIL" : "PASS");
+    }
+    expect: {
+        var a, b;
+        b = a = {
+            p: 42,
+        };
+        delete a.p;
+        console.log(b.p ? "FAIL" : "PASS");
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4119_4: {
+    options = {
+        booleans: true,
+        conditionals: true,
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a, b;
+        b = a = {
+            p: 42,
+        };
+        delete a.p;
+        console.log(!b ? "FAIL" : "PASS");
+    }
+    expect: {
+        var a, b;
+        b = a = {
+            p: 42,
+        };
+        delete a.p;
+        console.log((b, 0, "PASS"));
+    }
+    expect_stdout: "PASS"
+}

test/compress/functions.js

@@ -1483,8 +1483,7 @@ issue_2663_2: {
     }
     expect: {
         (function() {
-            var i;
-            for (i in { a: 1, b: 2, c: 3 })
+            for (var i in { a: 1, b: 2, c: 3 })
                 j = i, console.log(j);
             var j;
         })();
@@ -2677,7 +2676,7 @@ cross_references_3: {
                 };
                 return Math.square(n) + Math.cube(n);
             };
-        }(Math)(2));
+        }()(2));
         console.log(Math.square(3), Math.cube(3));
     }
     expect_stdout: [
@@ -4778,3 +4777,34 @@ issue_4006: {
     }
     expect_stdout: "-1"
 }
+
+issue_4155: {
+    options = {
+        functions: true,
+        inline: true,
+        merge_vars: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a;
+            (function() {
+                console.log(a);
+            })(a);
+            var b = function() {};
+            b && console.log(typeof b);
+        })();
+    }
+    expect: {
+        (function() {
+            void console.log(b);
+            var b = function() {};
+            b && console.log(typeof b);
+        })();
+    }
+    expect_stdout: [
+        "undefined",
+        "function",
+    ]
+}

test/compress/if_return.js

@@ -594,3 +594,72 @@ iife_if_return_simple: {
     }
     expect_stdout: "PASS"
 }
+
+nested_if_break: {
+    options = {
+        if_return: true,
+    }
+    input: {
+        for (var i = 0; i < 3; i++)
+            L1: if ("number" == typeof i) {
+                if (0 === i) break L1;
+                console.log(i);
+            }
+    }
+    expect: {
+        for (var i = 0; i < 3; i++)
+            L1: if ("number" == typeof i)
+                if (0 !== i) console.log(i);
+    }
+    expect_stdout: [
+        "1",
+        "2",
+    ]
+}
+
+nested_if_continue: {
+    options = {
+        conditionals: true,
+        if_return: true,
+        join_vars: true,
+        loops: true,
+    }
+    input: {
+        function f(n) {
+            var i = 0;
+            do {
+                if ("number" == typeof n) {
+                    if (0 === n) {
+                        console.log("even", i);
+                        continue;
+                    }
+                    if (1 === n) {
+                        console.log("odd", i);
+                        continue;
+                    }
+                    i++;
+                }
+            } while (0 <= (n -= 2));
+        }
+        f(37);
+        f(42);
+    }
+    expect: {
+        function f(n) {
+            for (var i = 0;
+                "number" == typeof n
+                    && (0 !== n
+                        ? 1 !== n
+                            ? i++
+                            : console.log("odd", i)
+                        : console.log("even", i)),
+                0 <= (n -= 2););
+        }
+        f(37);
+        f(42);
+    }
+    expect_stdout: [
+        "odd 18",
+        "even 21",
+    ]
+}

test/compress/join_vars.js

@@ -277,8 +277,8 @@ join_object_assignments_forin: {
     }
     expect: {
         console.log(function() {
-            var o = { a: "PASS" };
-            for (var a in o)
+            var o = { a: "PASS" }, a;
+            for (a in o)
                 return o[a];
         }());
     }

test/compress/keep_fargs.js

@@ -306,7 +306,6 @@ issue_2298: {
     expect: {
         !function() {
             (function() {
-                0;
                 try {
                     !function() {
                         (void 0)[1] = "foo";

test/compress/loops.js

@@ -756,7 +756,37 @@ empty_for_in_side_effects: {
     expect_warnings: [
         "WARN: Dropping unused variable b [test/compress/loops.js:4,16]",
         "INFO: Dropping unused loop variable a [test/compress/loops.js:1,17]",
-        "WARN: Side effects in object of for-in loop [test/compress/loops.js:1,17]",
+        "WARN: Side effects in object of for-in loop [test/compress/loops.js:2,17]",
+    ]
+}
+
+empty_for_in_prop_init: {
+    options = {
+        loops: true,
+        pure_getters: "strict",
+        unused: true,
+    }
+    input: {
+        console.log(function f() {
+            var a = "bar";
+            for ((a, f)[a] in console.log("foo"));
+            return a;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            var a = "bar";
+            console.log("foo");
+            return a;
+        }());
+    }
+    expect_stdout: [
+        "foo",
+        "bar",
+    ]
+    expect_warnings: [
+        "INFO: Dropping unused loop variable f [test/compress/loops.js:3,21]",
+        "WARN: Side effects in object of for-in loop [test/compress/loops.js:3,30]",
     ]
 }
 
@@ -933,3 +963,128 @@ issue_3634_2: {
     }
     expect_stdout: "1"
 }
+
+issue_4075: {
+    options = {
+        loops: true,
+        unused: true,
+    }
+    input: {
+        var a = "FAIL";
+        (function() {
+            for (a in { PASS: 0 });
+        })()
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        (function() {
+            for (a in { PASS: 0 });
+        })()
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4082: {
+    options = {
+        keep_fargs: "strict",
+        loops: true,
+        unused: true,
+    }
+    input: {
+        var a = "PASS";
+        (function(a) {
+            for (a in "foo")
+                var b;
+        })();
+        console.log(a);
+    }
+    expect: {
+        var a = "PASS";
+        (function(a) {
+            for (a in "foo");
+        })();
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_4084: {
+    options = {
+        keep_fargs: "strict",
+        loops: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            function f(a) {
+                var b = a++;
+                for (a in "foo");
+            }
+            f();
+            return typeof a;
+        }());
+    }
+    expect: {
+        console.log(function() {
+            (function() {
+                0;
+            })();
+            return typeof a;
+        }());
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4091_1: {
+    options = {
+        loops: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        try {
+            throw "FAIL";
+        } catch (e) {
+            for (var e in 42);
+        }
+        console.log(e && e);
+    }
+    expect: {
+        try {
+            throw "FAIL";
+        } catch (e) {
+            var e;
+        }
+        console.log(e && e);
+    }
+    expect_stdout: "undefined"
+}
+
+issue_4091_2: {
+    options = {
+        loops: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        try {
+            throw "FAIL";
+        } catch (e) {
+            for (e in 42);
+            var e;
+        }
+        console.log(e && e);
+    }
+    expect: {
+        try {
+            throw "FAIL";
+        } catch (e) {
+            var e;
+        }
+        console.log(e && e);
+    }
+    expect_stdout: "undefined"
+}

test/compress/numbers.js

@@ -91,7 +91,7 @@ evaluate_1: {
     expect: {
         console.log(
             x + 1 + 2,
-            2 * x,
+            2 * +x,
             +x + 1 + 2,
             1 + x + 2 + 3,
             3 | x,
@@ -130,7 +130,7 @@ evaluate_1_unsafe_math: {
     expect: {
         console.log(
             x + 1 + 2,
-            2 * x,
+            2 * +x,
             +x + 3,
             1 + x + 2 + 3,
             3 | x,
@@ -148,45 +148,52 @@ evaluate_1_unsafe_math: {
 evaluate_2: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: false,
     }
     input: {
-        var x = "42", y = null;
-        [
-            x + 1 + 2,
-            x * 1 * 2,
-            +x + 1 + 2,
-            1 + x + 2 + 3,
-            1 | x | 2 | 3,
-            1 + x-- + 2 + 3,
-            1 + (x*y + 2) + 3,
-            1 + (2 + x + 3),
-            1 + (2 + ~x + 3),
-            -y + (2 + ~x + 3),
-            1 & (2 & x & 3),
-            1 + (2 + (x |= 0) + 3),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var x = "" + num, y = null;
+            [
+                x + 1 + 2,
+                x * 1 * 2,
+                +x + 1 + 2,
+                1 + x + 2 + 3,
+                1 | x | 2 | 3,
+                1 + x-- + 2 + 3,
+                1 + (x*y + 2) + 3,
+                1 + (2 + x + 3),
+                1 + (2 + ~x + 3),
+                -y + (2 + ~x + 3),
+                1 & (2 & x & 3),
+                1 + (2 + (x |= 0) + 3),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect: {
-        var x = "42", y = null;
-        [
-            x + 1 + 2,
-            2 * x,
-            +x + 1 + 2,
-            1 + x + 2 + 3,
-            3 | x,
-            1 + x-- + 2 + 3,
-            x*y + 2 + 1 + 3,
-            1 + (2 + x + 3),
-            2 + ~x + 3 + 1,
-            2 + ~x + 3 - y,
-            0 & x,
-            2 + (x |= 0) + 3 + 1,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var x = "" + num, y = null;
+            [
+                x + "12",
+                2 * x,
+                +x + 1 + 2,
+                1 + x + "23",
+                3 | x,
+                1 + x-- + 2 + 3,
+                x*y + 2 + 1 + 3,
+                2 + x + 3 + 1,
+                2 + ~x + 3 + 1,
+                2 + ~x + 3,
+                0 & x,
+                2 + (x |= 0) + 3 + 1,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect_stdout: [
         "string 4212",
@@ -207,45 +214,52 @@ evaluate_2: {
 evaluate_2_unsafe_math: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: true,
     }
     input: {
-        var x = "42", y = null;
-        [
-            x + 1 + 2,
-            x * 1 * 2,
-            +x + 1 + 2,
-            1 + x + 2 + 3,
-            1 | x | 2 | 3,
-            1 + x-- + 2 + 3,
-            1 + (x*y + 2) + 3,
-            1 + (2 + x + 3),
-            1 + (2 + ~x + 3),
-            -y + (2 + ~x + 3),
-            1 & (2 & x & 3),
-            1 + (2 + (x |= 0) + 3),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var x = "" + num, y = null;
+            [
+                x + 1 + 2,
+                x * 1 * 2,
+                +x + 1 + 2,
+                1 + x + 2 + 3,
+                1 | x | 2 | 3,
+                1 + x-- + 2 + 3,
+                1 + (x*y + 2) + 3,
+                1 + (2 + x + 3),
+                1 + (2 + ~x + 3),
+                -y + (2 + ~x + 3),
+                1 & (2 & x & 3),
+                1 + (2 + (x |= 0) + 3),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect: {
-        var x = "42", y = null;
-        [
-            x + 1 + 2,
-            2 * x,
-            +x + 3,
-            1 + x + 2 + 3,
-            3 | x,
-            6 + x--,
-            x*y + 6,
-            1 + (2 + x + 3),
-            6 + ~x,
-            5 + ~x - y,
-            0 & x,
-            6 + (x |= 0),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var x = "" + num, y = null;
+            [
+                x + "12",
+                2 * x,
+                +x + 3,
+                1 + x + "23",
+                3 | x,
+                6 + x--,
+                x*y + 6,
+                6 + x,
+                6 + ~x,
+                5 + ~x,
+                0 & x,
+                6 + (x |= 0),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect_stdout: [
         "string 4212",
@@ -310,45 +324,52 @@ evaluate_4: {
 evaluate_5: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: false,
     }
     input: {
-        var a = "1";
-        [
-            +a + 2 + 3,
-            +a + 2 - 3,
-            +a - 2 + 3,
-            +a - 2 - 3,
-            2 + +a + 3,
-            2 + +a - 3,
-            2 - +a + 3,
-            2 - +a - 3,
-            2 + 3 + +a,
-            2 + 3 - +a,
-            2 - 3 + +a,
-            2 - 3 - +a,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var a = "" + num;
+            [
+                +a + 2 + 3,
+                +a + 2 - 3,
+                +a - 2 + 3,
+                +a - 2 - 3,
+                2 + +a + 3,
+                2 + +a - 3,
+                2 - +a + 3,
+                2 - +a - 3,
+                2 + 3 + +a,
+                2 + 3 - +a,
+                2 - 3 + +a,
+                2 - 3 - +a,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(1);
     }
     expect: {
-        var a = "1";
-        [
-            +a + 2 + 3,
-            +a + 2 - 3,
-            a - 2 + 3,
-            a - 2 - 3,
-            +a + 2 + 3,
-            +a + 2 - 3,
-            2 - a + 3,
-            2 - a - 3,
-            +a + 5,
-            5 - a,
-            +a - 1,
-            -1 - a,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var a = "" + num;
+            [
+                +a + 2 + 3,
+                +a + 2 - 3,
+                a - 2 + 3,
+                a - 2 - 3,
+                +a + 2 + 3,
+                +a + 2 - 3,
+                2 - a + 3,
+                2 - a - 3,
+                +a + 5,
+                5 - a,
+                +a - 1,
+                -1 - a,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(1);
     }
     expect_stdout: [
         "number 6",
@@ -369,45 +390,52 @@ evaluate_5: {
 evaluate_5_unsafe_math: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: true,
     }
     input: {
-        var a = "1";
-        [
-            +a + 2 + 3,
-            +a + 2 - 3,
-            +a - 2 + 3,
-            +a - 2 - 3,
-            2 + +a + 3,
-            2 + +a - 3,
-            2 - +a + 3,
-            2 - +a - 3,
-            2 + 3 + +a,
-            2 + 3 - +a,
-            2 - 3 + +a,
-            2 - 3 - +a,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var a = "" + num;
+            [
+                +a + 2 + 3,
+                +a + 2 - 3,
+                +a - 2 + 3,
+                +a - 2 - 3,
+                2 + +a + 3,
+                2 + +a - 3,
+                2 - +a + 3,
+                2 - +a - 3,
+                2 + 3 + +a,
+                2 + 3 - +a,
+                2 - 3 + +a,
+                2 - 3 - +a,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(1);
     }
     expect: {
-        var a = "1";
-        [
-            +a + 5,
-            +a + -1,
-            a - -1,
-            a - 5,
-            +a + 5,
-            +a + -1,
-            5 - a,
-            -1 - a,
-            +a + 5,
-            5 - a,
-            +a - 1,
-            -1 - a,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num) {
+            var a = "" + num;
+            [
+                +a + 5,
+                +a + -1,
+                a - -1,
+                a - 5,
+                +a + 5,
+                +a + -1,
+                5 - a,
+                -1 - a,
+                +a + 5,
+                5 - a,
+                +a - 1,
+                -1 - a,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(1);
     }
     expect_stdout: [
         "number 6",
@@ -546,37 +574,44 @@ evaluate_6_unsafe_math: {
 evaluate_7: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: false,
     }
     input: {
-        var x = "42", y;
-        [
-            +x + 2 + (3 + !y),
-            +x + 2 + (3 - !y),
-            +x + 2 - (3 + !y),
-            +x + 2 - (3 - !y),
-            +x - 2 + (3 + !y),
-            +x - 2 + (3 - !y),
-            +x - 2 - (3 + !y),
-            +x - 2 - (3 - !y),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num, y) {
+            var x = "" + num;
+            [
+                +x + 2 + (3 + !y),
+                +x + 2 + (3 - !y),
+                +x + 2 - (3 + !y),
+                +x + 2 - (3 - !y),
+                +x - 2 + (3 + !y),
+                +x - 2 + (3 - !y),
+                +x - 2 - (3 + !y),
+                +x - 2 - (3 - !y),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect: {
-        var x = "42", y;
-        [
-            +x + 2 + (3 + !y),
-            +x + 2 + (3 - !y),
-            +x + 2 - (3 + !y),
-            +x + 2 - (3 - !y),
-            x - 2 + (3 + !y),
-            x - 2 + (3 - !y),
-            x - 2 - (3 + !y),
-            x - 2 - (3 - !y),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num, y) {
+            var x = "" + num;
+            [
+                +x + 2 + (3 + !y),
+                +x + 2 + (3 - !y),
+                +x + 2 - (3 + !y),
+                +x + 2 - (3 - !y),
+                x - 2 + (3 + !y),
+                x - 2 + (3 - !y),
+                x - 2 - (3 + !y),
+                x - 2 - (3 - !y),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect_stdout: [
         "number 48",
@@ -593,37 +628,44 @@ evaluate_7: {
 evaluate_7_unsafe_math: {
     options = {
         evaluate: true,
+        reduce_vars: true,
         unsafe_math: true,
     }
     input: {
-        var x = "42", y;
-        [
-            +x + 2 + (3 + !y),
-            +x + 2 + (3 - !y),
-            +x + 2 - (3 + !y),
-            +x + 2 - (3 - !y),
-            +x - 2 + (3 + !y),
-            +x - 2 + (3 - !y),
-            +x - 2 - (3 + !y),
-            +x - 2 - (3 - !y),
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num, y) {
+            var x = "" + num;
+            [
+                +x + 2 + (3 + !y),
+                +x + 2 + (3 - !y),
+                +x + 2 - (3 + !y),
+                +x + 2 - (3 - !y),
+                +x - 2 + (3 + !y),
+                +x - 2 + (3 - !y),
+                +x - 2 - (3 + !y),
+                +x - 2 - (3 - !y),
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect: {
-        var x = "42", y;
-        [
-            +x + 5 + !y,
-            +x + 5 - !y,
-            +x + -1 - !y,
-            +x + -1 + !y,
-            x - -1 + !y,
-            x - -1 - !y,
-            x - 5 - !y,
-            x - 5 + !y,
-        ].forEach(function(n) {
-            console.log(typeof n, n);
-        });
+        function f(num, y) {
+            var x = "" + num;
+            [
+                +x + 5 + !y,
+                +x + 5 - !y,
+                +x + -1 - !y,
+                +x + -1 + !y,
+                x - -1 + !y,
+                x - -1 - !y,
+                x - 5 - !y,
+                x - 5 + !y,
+            ].forEach(function(n) {
+                console.log(typeof n, n);
+            });
+        }
+        f(42);
     }
     expect_stdout: [
         "number 48",
@@ -637,6 +679,22 @@ evaluate_7_unsafe_math: {
     ]
 }
 
+evaluate_8_unsafe_math: {
+    options = {
+        evaluate: true,
+        unsafe_math: true,
+    }
+    input: {
+        var a = [ "42" ];
+        console.log(a * (1 / 7));
+    }
+    expect: {
+        var a = [ "42" ];
+        console.log(+a / 7);
+    }
+    expect_stdout: "6"
+}
+
 NaN_redefined: {
     options = {
         evaluate: true,
@@ -1251,3 +1309,29 @@ issue_3695: {
     }
     expect_stdout: "NaN"
 }
+
+issue_4137: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log(+(A = []) * (A[0] = 1));
+    }
+    expect: {
+        console.log(+(A = []) * (A[0] = 1));
+    }
+    expect_stdout: "0"
+}
+
+issue_4142: {
+    options = {
+        evaluate: true,
+    }
+    input: {
+        console.log("" + +(0 === console));
+    }
+    expect: {
+        console.log("" + +(0 === console));
+    }
+    expect_stdout: "0"
+}

test/compress/reduce_vars.js

@@ -120,7 +120,7 @@ modified: {
     expect: {
         function f0() {
             var b = 2;
-            b++;
+            +b;
             console.log(2);
             console.log(4);
         }
@@ -1624,7 +1624,7 @@ defun_label: {
     expect_stdout: true
 }
 
-double_reference: {
+double_reference_1: {
     options = {
         reduce_funcs: true,
         reduce_vars: true,
@@ -1638,6 +1638,32 @@ double_reference: {
             g();
         }
     }
+    expect: {
+        function f() {
+            var g = function g() {
+                g();
+            };
+            g();
+        }
+    }
+}
+
+double_reference_2: {
+    options = {
+        functions: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            var g = function g() {
+                g();
+            };
+            g();
+        }
+    }
     expect: {
         function f() {
             (function g() {
@@ -1647,6 +1673,60 @@ double_reference: {
     }
 }
 
+double_reference_3: {
+    options = {
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var x = function f() {
+            return f;
+        };
+        function g() {
+            return x();
+        }
+        console.log(g() === g());
+    }
+    expect: {
+        var x = function f() {
+            return f;
+        };
+        function g() {
+            return x();
+        }
+        console.log(g() === g());
+    }
+    expect_stdout: "true"
+}
+
+double_reference_4: {
+    options = {
+        comparisons: true,
+        functions: true,
+        inline: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var x = function f() {
+            return f;
+        };
+        function g() {
+            return x();
+        }
+        console.log(g() === g());
+    }
+    expect: {
+        console.log(true);
+    }
+    expect_stdout: "true"
+}
+
 iife_arguments_1: {
     options = {
         reduce_funcs: true,
@@ -1686,8 +1766,35 @@ iife_arguments_2: {
     }
     expect: {
         (function() {
-            console.log(function f() {
+            var x = function f() {
                 return f;
+            };
+            console.log(x() === arguments[0]);
+        })();
+    }
+    expect_stdout: true
+}
+
+iife_arguments_3: {
+    options = {
+        functions: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var x = function f() {
+                return f;
+            };
+            console.log(x() === arguments[0]);
+        })();
+    }
+    expect: {
+        (function() {
+            console.log(function x() {
+                return x;
             }() === arguments[0]);
         })();
     }
@@ -2069,6 +2176,7 @@ issue_1670_6: {
         keep_fargs: false,
         reduce_funcs: true,
         reduce_vars: true,
+        sequences: true,
         side_effects: true,
         switches: true,
         unused: true,
@@ -2086,10 +2194,9 @@ issue_1670_6: {
         })(1);
     }
     expect: {
-        (function(a) {
-            a = 1;
-            console.log(a);
-        })(1);
+        (function() {
+            console.log(1);
+        })();
     }
     expect_stdout: "1"
 }
@@ -2308,7 +2415,7 @@ redefine_farg_2: {
         console.log(typeof [], "number",function(a, b) {
             a = b;
             return typeof a;
-        }([]));
+        }());
     }
     expect_stdout: "object number undefined"
 }
@@ -5483,7 +5590,7 @@ 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"

test/compress/sequences.js

@@ -877,7 +877,7 @@ for_init_var: {
     expect_stdout: "PASS"
 }
 
-forin: {
+forin_1: {
     options = {
         sequences: true,
     }
@@ -895,6 +895,49 @@ forin: {
     expect_stdout: "PASS"
 }
 
+forin_2: {
+    options = {
+        evaluate: true,
+        inline: true,
+        reduce_vars: true,
+        sequences: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            p: 1,
+            q: 2,
+        };
+        var k = "k";
+        for ((console.log("exp"), o)[function() {
+            console.log("prop");
+            return k;
+        }()] in function() {
+            console.log("obj");
+            return o;
+        }())
+            console.log(o.k, o[o.k]);
+    }
+    expect: {
+        var o = {
+            p: 1,
+            q: 2,
+        };
+        for ((console.log("exp"), o)[console.log("prop"), "k"] in console.log("obj"), o)
+            console.log(o.k, o[o.k]);
+    }
+    expect_stdout: [
+        "obj",
+        "exp",
+        "prop",
+        "p 1",
+        "exp",
+        "prop",
+        "q 2",
+    ]
+}
+
 call: {
     options = {
         sequences: true,
@@ -1112,3 +1155,25 @@ issue_3703: {
     }
     expect_stdout: "PASS"
 }
+
+issue_4079: {
+    options = {
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        try {
+            typeof (0, A);
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect: {
+        try {
+            A;
+        } catch (e) {
+            console.log("PASS");
+        }
+    }
+    expect_stdout: "PASS"
+}

test/compress/side_effects.js

@@ -245,6 +245,31 @@ unsafe_builtin_2: {
     expect_stdout: "object PASS PASS"
 }
 
+unsafe_builtin_3: {
+    options = {
+        conditionals: true,
+        side_effects: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var o = {};
+        if (42 < Math.random())
+            o.p = "FAIL";
+        else
+            o.p = "PASS";
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect: {
+        var o = {};
+        o.p = 42 < Math.random() ? "FAIL" : "PASS";
+        for (var k in o)
+            console.log(k, o[k]);
+    }
+    expect_stdout: "p PASS"
+}
+
 unsafe_string_replace: {
     options = {
         side_effects: true,

test/input/reduce/label.js

@@ -1,9 +1,3 @@
-var o = this;
-
-for (var k in o) L17060: {
-    a++;
+UNUSED: {
+    console.log(0 - .1 - .1 - .1);
 }
-
-var a;
-
-console.log(k);

test/input/reduce/label.reduced.js

@@ -1,15 +1,12 @@
 // (beautified)
-var o = this;
-
-for (var k in o) {}
-
-var a;
-
-console.log(k);
-// output: a
+console.log(0 - 1 - .1 - .1);
+// output: -1.2000000000000002
 // 
-// minify: k
+// minify: -1.2
 // 
 // options: {
+//   "compress": {
+//     "unsafe_math": true
+//   },
 //   "mangle": false
 // }

test/mocha/reduce.js

@@ -24,6 +24,9 @@ describe("test/reduce.js", function() {
     });
     it("Should eliminate unreferenced labels", function() {
         var result = reduce_test(read("test/input/reduce/label.js"), {
+            compress: {
+                unsafe_math: true,
+            },
             mangle: false,
         }, {
             verbose: false,

test/reduce.js

@@ -112,19 +112,18 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
             // no structural AST changes before this point.
             if (node.start._permute >= REPLACEMENTS.length) return;
 
-            if (parent instanceof U.AST_Assign
-                    && parent.left === node
-                || parent instanceof U.AST_Unary
-                    && parent.expression === node
-                    && ["++", "--", "delete"].indexOf(parent.operator) >= 0) {
-                // ignore lvalues
+            // ignore lvalues
+            if (parent instanceof U.AST_Assign && parent.left === node) return;
+            if (parent instanceof U.AST_Unary && parent.expression === node) switch (parent.operator) {
+              case "++":
+              case "--":
+              case "delete":
                 return;
             }
-            if ((parent instanceof U.AST_For || parent instanceof U.AST_ForIn)
-                && parent.init === node && node instanceof U.AST_Var) {
-                // preserve for (var ...)
-                return node;
-            }
+            // preserve for (var xxx; ...)
+            if (parent instanceof U.AST_For && parent.init === node && node instanceof U.AST_Var) return node;
+            // preserve for (xxx in ...)
+            if (parent instanceof U.AST_ForIn && parent.init === node) return node;
 
             // node specific permutations with no parent logic
 
@@ -452,6 +451,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                 node.start = JSON.parse(JSON.stringify(node.start));
                 node.start._permute = 0;
             }));
+            var before_iterations = testcase;
             for (var c = 0; c < max_iterations; ++c) {
                 if (verbose && pass == 1 && c % 25 == 0) {
                     log("// reduce test pass " + pass + ", iteration " + c + ": " + testcase.length + " bytes");
@@ -494,7 +494,7 @@ module.exports = function reduce_test(testcase, minify_options, reduce_options)
                     }
                 }
             }
-            if (c == 0) break;
+            if (before_iterations === testcase) break;
             if (verbose) {
                 log("// reduce test pass " + pass + ": " + testcase.length + " bytes");
             }
@@ -557,7 +557,7 @@ function try_beautify(testcase, minify_options, expected, result_cache, timeout)
             code: testcase,
         };
     } else {
-        var actual = run_code(result.code, toplevel, result_cache, timeout);
+        var actual = run_code(result.code, toplevel, result_cache, timeout).result;
         if (!sandbox.same_stdout(expected, actual)) return {
             code: testcase,
         };
@@ -650,7 +650,15 @@ function wrap_with_console_log(node) {
 
 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));
+    var value = result_cache[key];
+    if (!value) {
+        var start = Date.now();
+        result_cache[key] = value = {
+            result: sandbox.run_code(code, toplevel, timeout),
+            elapsed: Date.now() - start,
+        };
+    }
+    return value;
 }
 
 function compare_run_code(code, minify_options, result_cache, max_timeout) {
@@ -658,21 +666,19 @@ function compare_run_code(code, minify_options, result_cache, max_timeout) {
     if (minified.error) return minified;
 
     var toplevel = sandbox.has_toplevel(minify_options);
-    var elapsed = Date.now();
-    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(minified.code, toplevel, result_cache, timeout);
+    var unminified = run_code(code, toplevel, result_cache, max_timeout);
+    var timeout = Math.min(100 * unminified.elapsed, max_timeout);
+    var minified_result = run_code(minified.code, toplevel, result_cache, timeout).result;
 
-    if (sandbox.same_stdout(unminified_result, minified_result)) {
-        return is_timed_out(unminified_result) && is_timed_out(minified_result) && {
+    if (sandbox.same_stdout(unminified.result, minified_result)) {
+        return is_timed_out(unminified.result) && is_timed_out(minified_result) && {
             timed_out: true,
         };
     }
     return {
-        unminified_result: unminified_result,
+        unminified_result: unminified.result,
         minified_result: minified_result,
-        elapsed: elapsed,
+        elapsed: unminified.elapsed,
     };
 }
 

test/ufuzz/actions.js

@@ -1,9 +1,41 @@
-require("../../tools/exit");
-
 var get = require("https").get;
 var parse = require("url").parse;
-var base = process.argv[2];
-var token = process.argv[3];
+
+var base, token, run_number, eldest = true;
+exports.init = function(url, auth, num) {
+    base = url;
+    token = auth;
+    run_number = num;
+};
+exports.should_stop = function(callback) {
+    read(base + "/actions/runs?per_page=100", function(reply) {
+        if (!reply || !Array.isArray(reply.workflow_runs)) return;
+        var runs = reply.workflow_runs.filter(function(workflow) {
+            return workflow.status != "completed";
+        }).sort(function(a, b) {
+            return b.run_number - a.run_number;
+        });
+        var found = false, remaining = 20;
+        (function next() {
+            if (!runs.length) return;
+            var workflow = runs.pop();
+            if (workflow.event == "schedule" && workflow.run_number == run_number) found = true;
+            read(workflow.jobs_url, function(reply) {
+                if (!reply || !Array.isArray(reply.jobs)) return;
+                if (!reply.jobs.every(function(job) {
+                    if (job.status == "completed") return true;
+                    remaining--;
+                    return found || workflow.event != "schedule";
+                })) return;
+                if (remaining >= 0) {
+                    next();
+                } else {
+                    callback();
+                }
+            });
+        })();
+    });
+};
 
 function read(url, callback) {
     var options = parse(url);
@@ -21,29 +53,3 @@ function read(url, callback) {
         });
     });
 }
-
-var queued = 0, total = 0, earliest, now = Date.now();
-process.on("beforeExit", function() {
-    if (queued > 3) {
-        process.stdout.write("0");
-    } else if (now - earliest > 0 && total > 1) {
-        process.stdout.write(Math.min(20 * (now - earliest) / (total - 1), 6300000).toFixed(0));
-    } else {
-        process.stdout.write("3600000");
-    }
-});
-read(base + "/actions/workflows/ufuzz.yml/runs?event=schedule", function(reply) {
-    reply.workflow_runs.filter(function(workflow) {
-        return /^(in_progress|queued|)$/.test(workflow.status);
-    }).forEach(function(workflow) {
-        read(workflow.jobs_url, function(reply) {
-            reply.jobs.forEach(function(job) {
-                if (job.status == "queued") queued++;
-                total++;
-                if (!job.started_at) return;
-                var start = new Date(job.started_at);
-                if (!(earliest < start)) earliest = start;
-            });
-        });
-    });
-});

test/ufuzz/index.js

@@ -496,11 +496,16 @@ function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn
         var label = createLabel(canBreak, canContinue);
         canBreak = label.break || enableLoopControl(canBreak, CAN_BREAK);
         canContinue = label.continue || enableLoopControl(canContinue, CAN_CONTINUE);
-        var optElementVar = "";
-        if (rng(5) > 1) {
-            optElementVar = "c = 1 + c; var " + createVarName(MANDATORY) + " = expr" + loop + "[key" + loop + "]; ";
-        }
-        return "{var expr" + loop + " = " + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "; " + label.target + " for (var key" + loop + " in expr" + loop + ") {" + optElementVar + createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + "}}";
+        var key = rng(10) ? "key" + loop : getVarName();
+        return [
+            "{var expr" + loop + " = " + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "; ",
+            label.target + " for (",
+            /^key/.test(key) ? "var " : "",
+            key + " in expr" + loop + ") {",
+            rng(5) > 1 ? "c = 1 + c; var " + createVarName(MANDATORY) + " = expr" + loop + "[" + key + "]; " : "",
+            createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth),
+            "}}",
+        ].join("");
       case STMT_SEMI:
         return use_strict && rng(20) === 0 ? '"use strict";' : ";";
       case STMT_EXPR:

test/ufuzz/job.js

@@ -1,39 +1,63 @@
+var actions = require("./actions");
 var child_process = require("child_process");
 
-var ping = 5 * 60 * 1000;
-var period = +process.argv[2];
-var endTime = Date.now() + period;
-for (var i = 0; i < 2; i++) spawn(endTime);
-
-function spawn(endTime) {
-    var child = child_process.spawn("node", [
-        "--max-old-space-size=2048",
-        "test/ufuzz"
-    ], {
-        stdio: [ "ignore", "pipe", "pipe" ]
-    }).on("exit", respawn);
-    var stdout = "";
-    child.stdout.on("data", function(data) {
-        stdout += data;
+var args = [
+    "--max-old-space-size=2048",
+    "test/ufuzz",
+];
+var iterations;
+switch (process.argv.length) {
+  case 3:
+    iterations = +process.argv[2];
+    args.push(iterations);
+    break;
+  case 5:
+    actions.init(process.argv[2], process.argv[3], +process.argv[4]);
+    break;
+  default:
+    throw new Error("invalid parameters");
+}
+var tasks = [ run(), run() ];
+if (iterations) return;
+var alive = setInterval(function() {
+    actions.should_stop(function() {
+        clearInterval(alive);
+        tasks.forEach(function(kill) {
+            kill();
+        });
     });
-    var stderr = "";
-    child.stderr.on("data", trap).pipe(process.stdout);
-    var keepAlive = setInterval(function() {
-        var end = stdout.lastIndexOf("\r");
-        console.log(stdout.slice(stdout.lastIndexOf("\r", end - 1) + 1, end));
-        stdout = stdout.slice(end + 1);
-    }, ping);
-    var timer = setTimeout(function() {
-        clearInterval(keepAlive);
+}, 8 * 60 * 1000);
+
+function run() {
+    var child, stdout, stderr, log;
+    spawn();
+    return function() {
+        clearInterval(log);
         child.removeListener("exit", respawn);
         child.kill();
-    }, endTime - Date.now());
+    };
+
+    function spawn() {
+        child = child_process.spawn("node", args, {
+            stdio: [ "ignore", "pipe", "pipe" ]
+        }).on("exit", respawn);
+        stdout = "";
+        child.stdout.on("data", function(data) {
+            stdout += data;
+        });
+        stderr = "";
+        child.stderr.on("data", trap).pipe(process.stdout);
+        log = setInterval(function() {
+            var end = stdout.lastIndexOf("\r");
+            console.log(stdout.slice(stdout.lastIndexOf("\r", end - 1) + 1, end));
+            stdout = stdout.slice(end + 1);
+        }, 5 * 60 * 1000);
+    }
 
     function respawn() {
         console.log(stdout.replace(/[^\r\n]*\r/g, ""));
-        clearInterval(keepAlive);
-        clearTimeout(timer);
-        spawn(endTime);
+        clearInterval(log);
+        if (!iterations) spawn();
     }
 
     function trap(data) {