v3.1.7

fixes #2423

README.md

@@ -221,7 +221,7 @@ to prevent the `require`, `exports` and `$` names from being changed.
 is a separate step, different from variable name mangling.  Pass
 `--mangle-props` to enable it.  It will mangle all properties in the
 input code with the exception of built in DOM properties and properties
-in core javascript classes.  For example:
+in core JavaScript classes.  For example:
 
 ```javascript
 // example.js
@@ -236,7 +236,7 @@ x.bar_ = 2;
 x["baz_"] = 3;
 console.log(x.calc());
 ```
-Mangle all properties (except for javascript `builtins`):
+Mangle all properties (except for JavaScript `builtins`):
 ```bash
 $ uglifyjs example.js -c -m --mangle-props
 ```
@@ -515,7 +515,6 @@ if (result.error) throw result.error;
 
 ```javascript
 {
-    warnings: false,
     parse: {
         // parse options
     },
@@ -538,6 +537,7 @@ if (result.error) throw result.error;
     nameCache: null, // or specify a name cache object
     toplevel: false,
     ie8: false,
+    warnings: false,
 }
 ```
 
@@ -632,6 +632,12 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 
 - `hoist_funs` (default: `true`) -- hoist function declarations
 
+- `hoist_props` (default: `false`) -- hoist properties from constant object and
+  array literals into regular variables subject to a set of constraints. For example:
+  `var o={p:1, q:2}; f(o.p, o.q);` is converted to `f(1, 2);`. Note: `hoist_props`
+  works best with `mangle` enabled, the `compress` option `passes` set to `2` or higher,
+  and the `compress` option `toplevel` enabled.
+
 - `hoist_vars` (default: `false`) -- hoist `var` declarations (this is `false`
   by default because it seems to increase the size of the output in general)
 
@@ -645,6 +651,10 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   compressor from discarding unused function arguments.  You need this
   for code which relies on `Function.length`.
 
+- `keep_fnames` (default: `false`) -- Pass `true` to prevent the
+  compressor from discarding function names.  Useful for code relying on
+  `Function.prototype.name`. See also: the `keep_fnames` [mangle option](#mangle).
+
 - `keep_infinity` (default: `false`) -- default `false`. Pass `true` to prevent `Infinity` from
   being compressed into `1/0`, which may cause performance issues on Chrome.
 
@@ -709,6 +719,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   `foo === void 0`.  Note: recommend to set this value to `false` for IE10 and
   earlier versions due to known issues.
 
+- `unsafe` (default: `false`) -- apply "unsafe" transformations (discussion below)
+
 - `unsafe_comps` (default: `false`) -- Reverse `<` and `<=` to `>` and `>=` to
   allow improved compression. This might be unsafe when an at least one of two
   operands is an object with computed values due the use of methods like `get`,
@@ -716,8 +728,6 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   comparison are switching. Compression only works if both `comparisons` and
   `unsafe_comps` are both set to true.
 
-- `unsafe` (default: `false`) -- apply "unsafe" transformations (discussion below)
-
 - `unsafe_Func` (default: `false`) -- compress and mangle `Function(args, code)`
   when both `args` and `code` are string literals.
 
@@ -738,15 +748,19 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 
 ## Mangle options
 
+- `eval` (default `false`). Pass `true` to mangle names visible in scopes
+  where `eval` or `with` are used.
+
+- `keep_fnames` (default `false`).  Pass `true` to not mangle function names.
+  Useful for code relying on `Function.prototype.name`. See also: the `keep_fnames`
+  [compress option](#compress-options).
+
 - `reserved` (default `[]`). Pass an array of identifiers that should be
   excluded from mangling. Example: `["foo", "bar"]`.
 
 - `toplevel` (default `false`). Pass `true` to mangle names declared in the
   top level scope.
 
-- `eval` (default `false`). Pass `true` to mangle names visible in scopes
-  where `eval` or `with` are used.
-
 Examples:
 
 ```javascript
@@ -1052,7 +1066,7 @@ in total it's a bit more than just using UglifyJS's own parser.
 ### Uglify Fast Minify Mode
 
 It's not well known, but whitespace removal and symbol mangling accounts
-for 95% of the size reduction in minified code for most javascript - not
+for 95% of the size reduction in minified code for most JavaScript - not
 elaborate code transforms. One can simply disable `compress` to speed up
 Uglify builds by 3 to 4 times. In this fast `mangle`-only mode Uglify has
 comparable minify speeds and gzip sizes to

lib/compress.js

@@ -60,6 +60,7 @@ function Compressor(options, false_by_default) {
         expression    : false,
         global_defs   : {},
         hoist_funs    : !false_by_default,
+        hoist_props   : false,
         hoist_vars    : false,
         ie8           : false,
         if_return     : !false_by_default,
@@ -151,7 +152,7 @@ merge(Compressor.prototype, {
         var last_count = 1 / 0;
         for (var pass = 0; pass < passes; pass++) {
             if (pass > 0 || this.option("reduce_vars"))
-                node.reset_opt_flags(this, true);
+                node.reset_opt_flags(this);
             node = node.transform(this);
             if (passes > 1) {
                 var count = 0;
@@ -190,6 +191,7 @@ merge(Compressor.prototype, {
         if (node._squeezed) return node;
         var was_scope = false;
         if (node instanceof AST_Scope) {
+            node = node.hoist_properties(this);
             node = node.hoist_declarations(this);
             was_scope = true;
         }
@@ -283,8 +285,9 @@ merge(Compressor.prototype, {
         self.transform(tt);
     });
 
-    AST_Node.DEFMETHOD("reset_opt_flags", function(compressor, rescan) {
-        var reduce_vars = rescan && compressor.option("reduce_vars");
+    AST_Toplevel.DEFMETHOD("reset_opt_flags", function(compressor) {
+        var reduce_vars = compressor.option("reduce_vars");
+        var unused = compressor.option("unused");
         // Stack of look-up tables to keep track of whether a `SymbolDef` has been
         // properly assigned before use:
         // - `push()` & `pop()` when visiting conditional branches
@@ -308,16 +311,31 @@ merge(Compressor.prototype, {
                 if (node instanceof AST_SymbolRef) {
                     var d = node.definition();
                     d.references.push(node);
-                    if (d.fixed === undefined || !safe_to_read(d)
-                        || is_modified(node, 0, is_immutable(node))) {
+                    if (d.fixed === undefined || !safe_to_read(d) || d.single_use == "m") {
                         d.fixed = false;
-                    } else {
-                        var parent = tw.parent();
-                        if (parent instanceof AST_Assign && parent.operator == "=" && node === parent.right
-                            || parent instanceof AST_Call && node !== parent.expression
-                            || parent instanceof AST_Return && node === parent.value && node.scope !== d.scope
-                            || parent instanceof AST_VarDef && node === parent.value) {
-                            d.escaped = true;
+                    } else if (d.fixed) {
+                        var value = node.fixed_value();
+                        if (unused && value && d.references.length == 1) {
+                            if (value instanceof AST_Lambda) {
+                                d.single_use = d.scope === node.scope
+                                        && !(d.orig[0] instanceof AST_SymbolFunarg)
+                                    || value.is_constant_expression(node.scope);
+                            } else {
+                                d.single_use = d.scope === node.scope
+                                    && loop_ids[d.id] === in_loop
+                                    && value.is_constant_expression();
+                                }
+                        } else {
+                            d.single_use = false;
+                        }
+                        if (is_modified(node, value, 0, is_immutable(value))) {
+                            if (d.single_use) {
+                                d.single_use = "m";
+                            } else {
+                                d.fixed = false;
+                            }
+                        } else {
+                            mark_escaped(d, node, value, 0);
                         }
                     }
                 }
@@ -365,6 +383,10 @@ merge(Compressor.prototype, {
                     } else {
                         d.fixed = node;
                         mark(d, true);
+                        if (unused && d.references.length == 1) {
+                            d.single_use = d.scope === d.references[0].scope
+                                || node.is_constant_expression(d.references[0].scope);
+                        }
                     }
                     var save_ids = safe_ids;
                     safe_ids = Object.create(null);
@@ -404,8 +426,7 @@ merge(Compressor.prototype, {
                     pop();
                     return true;
                 }
-                if (node instanceof AST_Binary
-                    && (node.operator == "&&" || node.operator == "||")) {
+                if (node instanceof AST_Binary && lazy_op(node.operator)) {
                     node.left.walk(tw);
                     push();
                     node.right.walk(tw);
@@ -516,6 +537,7 @@ merge(Compressor.prototype, {
                 }
                 return true;
             }
+            return def.fixed instanceof AST_Defun;
         }
 
         function safe_to_assign(def, value) {
@@ -538,6 +560,7 @@ merge(Compressor.prototype, {
         }
 
         function reset_def(def) {
+            def.direct_access = false;
             def.escaped = false;
             if (def.scope.uses_eval) {
                 def.fixed = false;
@@ -551,34 +574,68 @@ merge(Compressor.prototype, {
             def.single_use = undefined;
         }
 
-        function is_immutable(node) {
-            var value = node.fixed_value();
+        function is_immutable(value) {
             if (!value) return false;
-            if (value.is_constant()) return true;
-            if (compressor.option("unused")) {
-                var d = node.definition();
-                if (d.single_use === undefined) {
-                    d.single_use = loop_ids[d.id] === in_loop
-                        && d.scope === node.scope
-                        && value.is_constant_expression();
-                }
-                if (d.references.length == 1 && d.single_use) return true;
-            }
-            return value instanceof AST_Lambda;
+            return value.is_constant()
+                || value instanceof AST_Lambda
+                || value instanceof AST_This;
         }
 
-        function is_modified(node, level, immutable) {
+        function read_property(obj, key) {
+            if (key instanceof AST_Constant) key = key.getValue();
+            if (key instanceof AST_Node) return null;
+            var value;
+            if (obj instanceof AST_Array) {
+                var elements = obj.elements;
+                if (key == "length") return make_node_from_constant(elements.length, obj);
+                if (typeof key == "number" && key in elements) value = elements[key];
+            } else if (obj instanceof AST_Object) {
+                var props = obj.properties;
+                for (var i = props.length; --i >= 0;) {
+                    var prop = props[i];
+                    if (!(prop instanceof AST_ObjectKeyVal)) return;
+                    if (!value && props[i].key === key) value = props[i].value;
+                }
+            }
+            return value instanceof AST_SymbolRef && value.fixed_value() || value;
+        }
+
+        function is_modified(node, value, level, immutable) {
             var parent = tw.parent(level);
             if (is_lhs(node, parent)
-                || !immutable && parent instanceof AST_Call && parent.expression === node) {
+                || !immutable
+                    && parent instanceof AST_Call
+                    && parent.expression === node
+                    && (!(value instanceof AST_Function) || value.contains_this(parent))) {
                 return true;
+            } else if (parent instanceof AST_Array || parent instanceof AST_Object) {
+                return is_modified(parent, parent, level + 1);
             } else if (parent instanceof AST_PropAccess && parent.expression === node) {
-                return !immutable && is_modified(parent, level + 1);
+                return !immutable && is_modified(parent, read_property(value, parent.property), level + 1);
             }
         }
+
+        function mark_escaped(d, node, value, level) {
+            var parent = tw.parent(level);
+            if (value instanceof AST_Constant || value instanceof AST_Function) return;
+            if (parent instanceof AST_Assign && parent.operator == "=" && node === parent.right
+                || parent instanceof AST_Call && node !== parent.expression
+                || parent instanceof AST_Return && node === parent.value && node.scope !== d.scope
+                || parent instanceof AST_VarDef && node === parent.value) {
+                d.escaped = true;
+                return;
+            } else if (parent instanceof AST_Array || parent instanceof AST_Object) {
+                mark_escaped(d, parent, parent, level + 1);
+            } else if (parent instanceof AST_PropAccess && node === parent.expression) {
+                value = read_property(value, parent.property);
+                mark_escaped(d, parent, value, level + 1);
+                if (value) return;
+            }
+            if (level == 0) d.direct_access = true;
+        }
     });
 
-    AST_SymbolRef.DEFMETHOD("fixed_value", function() {
+    AST_Symbol.DEFMETHOD("fixed_value", function() {
         var fixed = this.definition().fixed;
         if (!fixed || fixed instanceof AST_Node) return fixed;
         return fixed();
@@ -762,6 +819,7 @@ merge(Compressor.prototype, {
         function collapse(statements, compressor) {
             var scope = compressor.find_parent(AST_Scope);
             if (scope.uses_eval || scope.uses_with) return statements;
+            var args;
             var candidates = [];
             var stat_index = statements.length;
             while (--stat_index >= 0) {
@@ -779,9 +837,10 @@ merge(Compressor.prototype, {
                     // Locate symbols which may execute code outside of scanning range
                     var lvalues = get_lvalues(candidate);
                     if (lhs instanceof AST_SymbolRef) lvalues[lhs.name] = false;
+                    var one_off = lhs instanceof AST_Symbol && lhs.definition().references.length == 1;
                     var side_effects = value_has_side_effects(candidate);
                     var hit = candidate.name instanceof AST_SymbolFunarg;
-                    var abort = false, replaced = false;
+                    var abort = false, replaced = false, can_replace = !args || !hit;
                     var tt = new TreeTransformer(function(node, descend) {
                         if (abort) return node;
                         // Skip nodes before `candidate` as quickly as possible
@@ -806,7 +865,8 @@ merge(Compressor.prototype, {
                             return node;
                         }
                         // Replace variable with assignment when found
-                        if (!(node instanceof AST_SymbolDeclaration)
+                        if (can_replace
+                            && !(node instanceof AST_SymbolDeclaration)
                             && !is_lhs(node, parent)
                             && lhs.equivalent_to(node)) {
                             CHANGED = replaced = abort = true;
@@ -838,17 +898,18 @@ merge(Compressor.prototype, {
                         var sym;
                         if (node instanceof AST_Call
                             || node instanceof AST_Exit
-                            || node instanceof AST_PropAccess && node.has_side_effects(compressor)
+                            || node instanceof AST_PropAccess
+                                && (side_effects || node.expression.may_throw_on_access(compressor))
                             || node instanceof AST_SymbolRef
                                && (lvalues[node.name]
                                    || side_effects && !references_in_scope(node.definition()))
-                            || (sym = lhs_or_def(node)) && get_symbol(sym).name in lvalues
-                            || parent instanceof AST_Binary
-                                && (parent.operator == "&&" || parent.operator == "||")
-                            || parent instanceof AST_Case
-                            || parent instanceof AST_Conditional
-                            || parent instanceof AST_For
-                            || parent instanceof AST_If) {
+                            || (sym = lhs_or_def(node))
+                                && (sym instanceof AST_PropAccess || sym.name in lvalues)
+                            || (side_effects || !one_off)
+                                && (parent instanceof AST_Binary && lazy_op(parent.operator)
+                                    || parent instanceof AST_Case
+                                    || parent instanceof AST_Conditional
+                                    || parent instanceof AST_If)) {
                             if (!(node instanceof AST_Scope)) descend(node, tt);
                             abort = true;
                             return node;
@@ -856,6 +917,12 @@ merge(Compressor.prototype, {
                         // Skip (non-executed) functions and (leading) default case in switch statements
                         if (node instanceof AST_Default || node instanceof AST_Scope) return node;
                     });
+                    if (!can_replace) {
+                        for (var j = compressor.self().argnames.lastIndexOf(candidate.name) + 1; j < args.length; j++) {
+                            args[j].transform(tt);
+                        }
+                        can_replace = true;
+                    }
                     for (var i = stat_index; !abort && i < statements.length; i++) {
                         statements[i].transform(tt);
                     }
@@ -873,12 +940,18 @@ merge(Compressor.prototype, {
                     && iife.expression === fn) {
                     var fn_strict = compressor.has_directive("use strict");
                     if (fn_strict && fn.body.indexOf(fn_strict) < 0) fn_strict = false;
+                    var len = fn.argnames.length;
+                    args = iife.args.slice(len);
                     var names = Object.create(null);
-                    for (var i = fn.argnames.length; --i >= 0;) {
+                    for (var i = len; --i >= 0;) {
                         var sym = fn.argnames[i];
+                        var arg = iife.args[i];
+                        args.unshift(make_node(AST_VarDef, sym, {
+                            name: sym,
+                            value: arg
+                        }));
                         if (sym.name in names) continue;
                         names[sym.name] = true;
-                        var arg = iife.args[i];
                         if (!arg) arg = make_node(AST_Undefined, sym).transform(compressor);
                         else {
                             var tw = new TreeWalker(function(node) {
@@ -934,27 +1007,14 @@ merge(Compressor.prototype, {
                 }
             }
 
-            function get_symbol(node) {
-                while (node instanceof AST_PropAccess) node = node.expression;
-                return node;
-            }
-
             function get_lvalues(expr) {
                 var lvalues = Object.create(null);
                 if (expr instanceof AST_Unary) return lvalues;
-                var scope;
                 var tw = new TreeWalker(function(node, descend) {
-                    if (node instanceof AST_Scope) {
-                        var save_scope = scope;
-                        descend();
-                        scope = save_scope;
-                        return true;
-                    }
-                    if (node instanceof AST_SymbolRef || node instanceof AST_PropAccess) {
-                        var sym = get_symbol(node);
-                        if (sym instanceof AST_SymbolRef) {
-                            lvalues[sym.name] = lvalues[sym.name] || is_lhs(node, tw.parent());
-                        }
+                    var sym = node;
+                    while (sym instanceof AST_PropAccess) sym = sym.expression;
+                    if (sym instanceof AST_SymbolRef || sym instanceof AST_This) {
+                        lvalues[sym.name] = lvalues[sym.name] || is_lhs(node, tw.parent());
                     }
                 });
                 expr[expr instanceof AST_Assign ? "right" : "value"].walk(tw);
@@ -1431,9 +1491,10 @@ merge(Compressor.prototype, {
             return member(this.operator, unary_bool);
         });
         def(AST_Binary, function(){
-            return member(this.operator, binary_bool) ||
-                ( (this.operator == "&&" || this.operator == "||") &&
-                  this.left.is_boolean() && this.right.is_boolean() );
+            return member(this.operator, binary_bool)
+                || lazy_op(this.operator)
+                    && this.left.is_boolean()
+                    && this.right.is_boolean();
         });
         def(AST_Conditional, function(){
             return this.consequent.is_boolean() && this.alternative.is_boolean();
@@ -1502,6 +1563,7 @@ merge(Compressor.prototype, {
         node.DEFMETHOD("is_string", func);
     });
 
+    var lazy_op = makePredicate("&& ||");
     var unary_side_effects = makePredicate("delete ++ --");
 
     function is_lhs(node, parent) {
@@ -1613,35 +1675,6 @@ merge(Compressor.prototype, {
                     && unaryPrefix(this.operator);
             }
         });
-        // Obtain the constant value of an expression already known to be constant.
-        // Result only valid iff this.is_constant() is true.
-        AST_Node.DEFMETHOD("constant_value", function(compressor){
-            // Accomodate when option evaluate=false.
-            if (this instanceof AST_Constant && !(this instanceof AST_RegExp)) {
-                return this.value;
-            }
-            // Accomodate the common constant expressions !0 and -1 when option evaluate=false.
-            if (this instanceof AST_UnaryPrefix
-                && this.expression instanceof AST_Constant) switch (this.operator) {
-              case "!":
-                return !this.expression.value;
-              case "~":
-                return ~this.expression.value;
-              case "-":
-                return -this.expression.value;
-              case "+":
-                return +this.expression.value;
-              default:
-                throw new Error(string_template("Cannot evaluate unary expression {value}", {
-                    value: this.print_to_string()
-                }));
-            }
-            var result = this.evaluate(compressor);
-            if (result !== this) {
-                return result;
-            }
-            throw new Error(string_template("Cannot evaluate constant [{file}:{line},{col}]", this.start));
-        });
         def(AST_Statement, function(){
             throw new Error(string_template("Cannot evaluate a statement [{file}:{line},{col}]", this.start));
         });
@@ -1660,6 +1693,7 @@ merge(Compressor.prototype, {
                 var elements = [];
                 for (var i = 0, len = this.elements.length; i < len; i++) {
                     var element = this.elements[i];
+                    if (element instanceof AST_Function) continue;
                     var value = ev(element, compressor);
                     if (element === value) return this;
                     elements.push(value);
@@ -1683,6 +1717,7 @@ merge(Compressor.prototype, {
                     if (typeof Object.prototype[key] === 'function') {
                         return this;
                     }
+                    if (prop.value instanceof AST_Function) continue;
                     val[key] = ev(prop.value, compressor);
                     if (val[key] === prop.value) return this;
                 }
@@ -2141,18 +2176,22 @@ merge(Compressor.prototype, {
         }
         def(AST_Node, return_false);
         def(AST_Constant, return_true);
-        def(AST_Function, function(){
+        def(AST_Lambda, function(scope){
             var self = this;
             var result = true;
             self.walk(new TreeWalker(function(node) {
                 if (!result) return true;
                 if (node instanceof AST_SymbolRef) {
                     var def = node.definition();
-                    if (self.enclosed.indexOf(def) >= 0
-                        && self.variables.get(def.name) !== def) {
+                    if (member(def, self.enclosed)
+                        && !self.variables.has(def.name)) {
+                        if (scope) {
+                            var scope_def = scope.find_variable(node);
+                            if (def.undeclared ? !scope_def : scope_def === def) return true;
+                        }
                         result = false;
-                        return true;
                     }
+                    return true;
                 }
             }));
             return result;
@@ -2240,7 +2279,6 @@ merge(Compressor.prototype, {
         if (self.uses_eval || self.uses_with) return;
         var drop_funcs = !(self instanceof AST_Toplevel) || compressor.toplevel.funcs;
         var drop_vars = !(self instanceof AST_Toplevel) || compressor.toplevel.vars;
-        if (!drop_funcs && !drop_vars) return;
         var assign_as_unused = /keep_assign/.test(compressor.option("unused")) ? return_false : function(node) {
             if (node instanceof AST_Assign && (node.write_only || node.operator == "=")) {
                 return node.left;
@@ -2296,7 +2334,10 @@ merge(Compressor.prototype, {
                     });
                     return true;
                 }
-                if (assign_as_unused(node) instanceof AST_SymbolRef && scope === self) {
+                var sym;
+                if (scope === self
+                    && (sym = assign_as_unused(node)) instanceof AST_SymbolRef
+                    && self.variables.get(sym.name) === sym.definition()) {
                     if (node instanceof AST_Assign) node.right.walk(tw);
                     return true;
                 }
@@ -2369,13 +2410,16 @@ merge(Compressor.prototype, {
                     }
                 }
                 if (drop_funcs && node instanceof AST_Defun && node !== self) {
-                    if (!(node.name.definition().id in in_use_ids)) {
+                    var def = node.name.definition();
+                    if (!(def.id in in_use_ids)) {
                         compressor[node.name.unreferenced() ? "warn" : "info"]("Dropping unused function {name} [{file}:{line},{col}]", template(node.name));
+                        drop_decl(def, node.name);
                         return make_node(AST_EmptyStatement, node);
                     }
                     return node;
                 }
-                if (drop_vars && node instanceof AST_Definitions && !(tt.parent() instanceof AST_ForIn && tt.parent().init === node)) {
+                var parent = tt.parent();
+                if (node instanceof AST_Definitions && !(parent instanceof AST_ForIn && parent.init === node)) {
                     // place uninitialized names at the start
                     var body = [], head = [], tail = [];
                     // for unused names whose initialization has
@@ -2385,13 +2429,13 @@ merge(Compressor.prototype, {
                     node.definitions.forEach(function(def) {
                         if (def.value) def.value = def.value.transform(tt);
                         var sym = def.name.definition();
-                        if (sym.id in in_use_ids) {
+                        if (!drop_vars || sym.id in in_use_ids) {
                             if (def.name instanceof AST_SymbolVar) {
                                 var var_defs = var_defs_by_id.get(sym.id);
                                 if (var_defs.length > 1 && !def.value) {
                                     compressor.warn("Dropping duplicated definition of variable {name} [{file}:{line},{col}]", template(def.name));
                                     remove(var_defs, def);
-                                    remove(sym.orig, def.name);
+                                    drop_decl(sym, def.name);
                                     return;
                                 }
                             }
@@ -2424,7 +2468,7 @@ merge(Compressor.prototype, {
                             } else {
                                 compressor[def.name.unreferenced() ? "warn" : "info"]("Dropping unused variable {name} [{file}:{line},{col}]", template(def.name));
                             }
-                            remove(sym.orig, def.name);
+                            drop_decl(sym, def.name);
                         }
                     });
                     if (head.length == 0 && tail.length == 1 && tail[0].name instanceof AST_SymbolVar) {
@@ -2433,7 +2477,7 @@ merge(Compressor.prototype, {
                             var def = tail.pop();
                             compressor.warn("Converting duplicated definition of variable {name} to assignment [{file}:{line},{col}]", template(def.name));
                             remove(var_defs, def);
-                            remove(def.name.definition().orig, def.name);
+                            drop_decl(def.name.definition(), def.name);
                             side_effects.unshift(make_node(AST_Assign, def, {
                                 operator: "=",
                                 left: make_node(AST_SymbolRef, def.name, def.name),
@@ -2451,23 +2495,22 @@ merge(Compressor.prototype, {
                         }));
                     }
                     switch (body.length) {
-                        case 0:
+                      case 0:
                         return in_list ? MAP.skip : make_node(AST_EmptyStatement, node);
-                        case 1:
+                      case 1:
                         return body[0];
-                        default:
+                      default:
                         return in_list ? MAP.splice(body) : make_node(AST_BlockStatement, node, {
                             body: body
                         });
                     }
                 }
                 if (drop_vars) {
-                    var def = assign_as_unused(node);
-                    if (def instanceof AST_SymbolRef
-                        && !((def = def.definition()).id in in_use_ids)
-                        && self.variables.get(def.name) === def) {
+                    var sym = assign_as_unused(node);
+                    if (sym instanceof AST_SymbolRef
+                        && !(sym.definition().id in in_use_ids)) {
                         if (node instanceof AST_Assign) {
-                            return maintain_this_binding(tt.parent(), node, node.right.transform(tt));
+                            return maintain_this_binding(parent, node, node.right.transform(tt));
                         }
                         return make_node(AST_Number, node, {
                             value: 0
@@ -2516,6 +2559,14 @@ merge(Compressor.prototype, {
                         col  : sym.start.col
                     };
                 }
+
+                function drop_decl(def, decl) {
+                    remove(def.orig, decl);
+                    if (!def.orig.length) {
+                        def.scope.functions.del(def.name);
+                        def.scope.variables.del(def.name);
+                    }
+                }
             }
         );
         self.transform(tt);
@@ -2651,6 +2702,71 @@ merge(Compressor.prototype, {
         return self;
     });
 
+    AST_Scope.DEFMETHOD("hoist_properties", function(compressor){
+        var self = this;
+        if (!compressor.option("hoist_props") || compressor.has_directive("use asm")) return self;
+        var defs_by_id = Object.create(null);
+        var var_names = Object.create(null);
+        self.enclosed.forEach(function(def) {
+            var_names[def.name] = true;
+        });
+        self.variables.each(function(def, name) {
+            var_names[name] = true;
+        });
+        return self.transform(new TreeTransformer(function(node) {
+            if (node instanceof AST_VarDef) {
+                var sym = node.name, def, value;
+                if (sym.scope === self
+                    && !(def = sym.definition()).escaped
+                    && !def.single_use
+                    && !def.direct_access
+                    && (value = sym.fixed_value()) === node.value
+                    && value instanceof AST_Object) {
+                    var defs = new Dictionary();
+                    var assignments = [];
+                    value.properties.forEach(function(prop) {
+                        assignments.push(make_node(AST_VarDef, node, {
+                            name: make_sym(prop.key),
+                            value: prop.value
+                        }));
+                    });
+                    defs_by_id[def.id] = defs;
+                    return MAP.splice(assignments);
+                }
+            }
+            if (node instanceof AST_PropAccess && node.expression instanceof AST_SymbolRef) {
+                var defs = defs_by_id[node.expression.definition().id];
+                if (defs) {
+                    var key = node.property;
+                    if (key instanceof AST_Node) key = key.getValue();
+                    var def = defs.get(key);
+                    var sym = make_node(AST_SymbolRef, node, {
+                        name: def.name,
+                        scope: node.expression.scope,
+                        thedef: def
+                    });
+                    sym.reference({});
+                    return sym;
+                }
+            }
+
+            function make_sym(key) {
+                var prefix = sym.name + "_" + key.toString().replace(/[^a-z_$]+/ig, "_");
+                var name = prefix;
+                for (var i = 0; var_names[name]; i++) name = prefix + "$" + i;
+                var new_var = make_node(sym.CTOR, sym, {
+                    name: name,
+                    scope: self
+                });
+                var def = self.def_variable(new_var);
+                defs.set(key, def);
+                self.enclosed.push(def);
+                var_names[name] = true;
+                return new_var;
+            }
+        }));
+    });
+
     // drop_side_effect_free()
     // remove side-effect-free parts which only affects return value
     (function(def){
@@ -2698,14 +2814,12 @@ merge(Compressor.prototype, {
         def(AST_Binary, function(compressor, first_in_statement){
             var right = this.right.drop_side_effect_free(compressor);
             if (!right) return this.left.drop_side_effect_free(compressor, first_in_statement);
-            switch (this.operator) {
-              case "&&":
-              case "||":
+            if (lazy_op(this.operator)) {
                 if (right === this.right) return this;
                 var node = this.clone();
                 node.right = right;
                 return node;
-              default:
+            } else {
                 var left = this.left.drop_side_effect_free(compressor, first_in_statement);
                 if (!left) return this.right.drop_side_effect_free(compressor, first_in_statement);
                 return make_sequence(this, [ left, right ]);
@@ -3571,7 +3685,7 @@ merge(Compressor.prototype, {
                     }
                     if (cdr instanceof AST_Binary && !(cdr instanceof AST_Assign)) {
                         if (cdr.left.is_constant()) {
-                            if (cdr.operator == "||" || cdr.operator == "&&") {
+                            if (lazy_op(cdr.operator)) {
                                 expressions[++i] = expressions[j];
                                 break;
                             }
@@ -3727,6 +3841,11 @@ merge(Compressor.prototype, {
     });
 
     var commutativeOperators = makePredicate("== === != !== * & | ^");
+    function is_object(node) {
+        return node instanceof AST_Array
+            || node instanceof AST_Lambda
+            || node instanceof AST_Object;
+    }
 
     OPT(AST_Binary, function(self, compressor){
         function reversible() {
@@ -3762,7 +3881,8 @@ merge(Compressor.prototype, {
           case "!==":
             if ((self.left.is_string(compressor) && self.right.is_string(compressor)) ||
                 (self.left.is_number(compressor) && self.right.is_number(compressor)) ||
-                (self.left.is_boolean() && self.right.is_boolean())) {
+                (self.left.is_boolean() && self.right.is_boolean()) ||
+                self.left.equivalent_to(self.right)) {
                 self.operator = self.operator.substr(0, 2);
             }
             // XXX: intentionally falling down to the next case
@@ -3782,6 +3902,13 @@ merge(Compressor.prototype, {
                     if (self.operator.length == 2) self.operator += "=";
                 }
             }
+            // obj !== obj => false
+            else if (self.left instanceof AST_SymbolRef
+                && self.right instanceof AST_SymbolRef
+                && self.left.definition() === self.right.definition()
+                && is_object(self.left.fixed_value())) {
+                return make_node(self.operator[0] == "=" ? AST_True : AST_False, self);
+            }
             break;
         }
         if (compressor.option("booleans") && self.operator == "+" && compressor.in_boolean_context()) {
@@ -4071,8 +4198,7 @@ merge(Compressor.prototype, {
         // "x" + (y + "z")==>  "x" + y + "z"
         if (self.right instanceof AST_Binary
             && self.right.operator == self.operator
-            && (self.operator == "&&"
-                || self.operator == "||"
+            && (lazy_op(self.operator)
                 || (self.operator == "+"
                     && (self.right.left.is_string(compressor)
                         || (self.left.is_string(compressor)
@@ -4120,47 +4246,55 @@ merge(Compressor.prototype, {
                 d.fixed = fixed = make_node(AST_Function, fixed, fixed);
             }
             if (compressor.option("unused")
+                && fixed
                 && d.references.length == 1
-                && (d.single_use || fixed instanceof AST_Function
-                    && !(d.scope.uses_arguments && d.orig[0] instanceof AST_SymbolFunarg)
-                    && !d.scope.uses_eval
-                    && compressor.find_parent(AST_Scope) === fixed.parent_scope)) {
+                && d.single_use) {
                 var value = fixed.optimize(compressor);
                 return value === fixed ? fixed.clone(true) : value;
             }
-            if (compressor.option("evaluate") && fixed) {
-                if (d.should_replace === undefined) {
-                    var init = fixed.evaluate(compressor);
-                    if (init !== fixed && (compressor.option("unsafe_regexp") || !(init instanceof RegExp))) {
-                        init = make_node_from_constant(init, fixed);
-                        var value_length = init.optimize(compressor).print_to_string().length;
-                        var fn;
-                        if (has_symbol_ref(fixed)) {
-                            fn = function() {
-                                var result = init.optimize(compressor);
-                                return result === init ? result.clone(true) : result;
-                            };
-                        } else {
-                            value_length = Math.min(value_length, fixed.print_to_string().length);
-                            fn = function() {
-                                var result = best_of_expression(init.optimize(compressor), fixed);
-                                return result === init || result === fixed ? result.clone(true) : result;
-                            };
-                        }
-                        var name_length = d.name.length;
-                        var overhead = 0;
-                        if (compressor.option("unused") && !compressor.exposed(d)) {
-                            overhead = (name_length + 2 + value_length) / d.references.length;
-                        }
-                        d.should_replace = value_length <= name_length + overhead ? fn : false;
-                    } else {
-                        d.should_replace = false;
+            if (fixed && d.should_replace === undefined) {
+                var init;
+                if (fixed instanceof AST_This) {
+                    if (!(d.orig[0] instanceof AST_SymbolFunarg)
+                        && all(d.references, function(ref) {
+                            return d.scope === ref.scope;
+                        })) {
+                        init = fixed;
+                    }
+                } else {
+                    var ev = fixed.evaluate(compressor);
+                    if (ev !== fixed && (compressor.option("unsafe_regexp") || !(ev instanceof RegExp))) {
+                        init = make_node_from_constant(ev, fixed);
                     }
                 }
-                if (d.should_replace) {
-                    return d.should_replace();
+                if (init) {
+                    var value_length = init.optimize(compressor).print_to_string().length;
+                    var fn;
+                    if (has_symbol_ref(fixed)) {
+                        fn = function() {
+                            var result = init.optimize(compressor);
+                            return result === init ? result.clone(true) : result;
+                        };
+                    } else {
+                        value_length = Math.min(value_length, fixed.print_to_string().length);
+                        fn = function() {
+                            var result = best_of_expression(init.optimize(compressor), fixed);
+                            return result === init || result === fixed ? result.clone(true) : result;
+                        };
+                    }
+                    var name_length = d.name.length;
+                    var overhead = 0;
+                    if (compressor.option("unused") && !compressor.exposed(d)) {
+                        overhead = (name_length + 2 + value_length) / d.references.length;
+                    }
+                    d.should_replace = value_length <= name_length + overhead ? fn : false;
+                } else {
+                    d.should_replace = false;
                 }
             }
+            if (d.should_replace) {
+                return d.should_replace();
+            }
         }
         return self;
 
@@ -4454,19 +4588,69 @@ merge(Compressor.prototype, {
     });
 
     OPT(AST_Sub, function(self, compressor){
+        var expr = self.expression;
         var prop = self.property;
-        if (prop instanceof AST_String && compressor.option("properties")) {
-            prop = prop.getValue();
-            if (is_identifier_string(prop)) {
-                return make_node(AST_Dot, self, {
-                    expression : self.expression,
-                    property   : prop
-                }).optimize(compressor);
+        if (compressor.option("properties")) {
+            var key = prop.evaluate(compressor);
+            if (key !== prop) {
+                var property = "" + key;
+                if (is_identifier_string(property)
+                    && property.length <= prop.print_to_string().length + 1) {
+                    return make_node(AST_Dot, self, {
+                        expression: expr,
+                        property: property
+                    }).optimize(compressor);
+                }
+                if (!(prop instanceof AST_Number)) {
+                    var value = parseFloat(property);
+                    if (value.toString() == property) {
+                        prop = self.property = make_node(AST_Number, prop, {
+                            value: value
+                        });
+                    }
+                }
             }
-            var v = parseFloat(prop);
-            if (!isNaN(v) && v.toString() == prop) {
-                self.property = make_node(AST_Number, self.property, {
-                    value: v
+        }
+        if (is_lhs(self, compressor.parent())) return self;
+        if (key !== prop) {
+            var sub = self.flatten_object(property, compressor);
+            if (sub) {
+                expr = self.expression = sub.expression;
+                prop = self.property = sub.property;
+            }
+        }
+        if (compressor.option("properties") && compressor.option("side_effects")
+            && prop instanceof AST_Number && expr instanceof AST_Array) {
+            var index = prop.getValue();
+            var elements = expr.elements;
+            if (index in elements) {
+                var flatten = true;
+                var values = [];
+                for (var i = elements.length; --i > index;) {
+                    var value = elements[i].drop_side_effect_free(compressor);
+                    if (value) {
+                        values.unshift(value);
+                        if (flatten && value.has_side_effects(compressor)) flatten = false;
+                    }
+                }
+                var retValue = elements[index];
+                retValue = retValue instanceof AST_Hole ? make_node(AST_Undefined, retValue) : retValue;
+                if (!flatten) values.unshift(retValue);
+                while (--i >= 0) {
+                    var value = elements[i].drop_side_effect_free(compressor);
+                    if (value) values.unshift(value);
+                    else index--;
+                }
+                if (flatten) {
+                    values.push(retValue);
+                    return make_sequence(self, values).optimize(compressor);
+                } else return make_node(AST_Sub, self, {
+                    expression: make_node(AST_Array, expr, {
+                        elements: values
+                    }),
+                    property: make_node(AST_Number, prop, {
+                        value: index
+                    })
                 });
             }
         }
@@ -4478,7 +4662,8 @@ merge(Compressor.prototype, {
         return self;
     });
 
-    AST_Lambda.DEFMETHOD("contains_this", function() {
+    AST_Lambda.DEFMETHOD("contains_this", function(grandparent) {
+        if (grandparent instanceof AST_New) return false;
         var result;
         var self = this;
         self.walk(new TreeWalker(function(node) {
@@ -4489,25 +4674,40 @@ merge(Compressor.prototype, {
         return result;
     });
 
+    AST_PropAccess.DEFMETHOD("flatten_object", function(key, compressor) {
+        if (!compressor.option("properties")) return;
+        var expr = this.expression;
+        if (expr instanceof AST_Object) {
+            var props = expr.properties;
+            for (var i = props.length; --i >= 0;) {
+                var prop = props[i];
+                if ("" + prop.key == key) {
+                    if (!all(props, function(prop) {
+                        return prop instanceof AST_ObjectKeyVal;
+                    })) break;
+                    var value = prop.value;
+                    if (value instanceof AST_Function
+                        && value.contains_this(compressor.parent())) break;
+                    return make_node(AST_Sub, this, {
+                        expression: make_node(AST_Array, expr, {
+                            elements: props.map(function(prop) {
+                                return prop.value;
+                            })
+                        }),
+                        property: make_node(AST_Number, this, {
+                            value: i
+                        })
+                    });
+                }
+            }
+        }
+    });
+
     OPT(AST_Dot, function(self, compressor){
         var def = self.resolve_defines(compressor);
         if (def) {
             return def.optimize(compressor);
         }
-        if (compressor.option("unsafe") && self.expression instanceof AST_Object) {
-            var values = self.expression.properties;
-            for (var i = values.length; --i >= 0;) {
-                if (values[i].key === self.property) {
-                    var value = values[i].value;
-                    if (value instanceof AST_Function ? !value.contains_this() : !value.has_side_effects(compressor)) {
-                        var obj = self.expression.clone();
-                        obj.properties = obj.properties.slice();
-                        obj.properties.splice(i, 1);
-                        return make_sequence(self, [ obj, value ]).optimize(compressor);
-                    }
-                }
-            }
-        }
         if (compressor.option("unsafe_proto")
             && self.expression instanceof AST_Dot
             && self.expression.property == "prototype") {
@@ -4530,6 +4730,9 @@ merge(Compressor.prototype, {
                 break;
             }
         }
+        if (is_lhs(self, compressor.parent())) return self;
+        var sub = self.flatten_object(self.property, compressor);
+        if (sub) return sub.optimize(compressor);
         var ev = self.evaluate(compressor);
         if (ev !== self) {
             ev = make_node_from_constant(ev, self).optimize(compressor);

package.json

@@ -4,7 +4,7 @@
   "homepage": "http://lisperator.net/uglifyjs",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.1.4",
+  "version": "3.1.7",
   "engines": {
     "node": ">=0.8.0"
   },

test/compress/arrays.js

@@ -128,50 +128,110 @@ constant_join_3: {
 
 for_loop: {
     options = {
-        unsafe      : true,
-        unused      : true,
-        evaluate    : true,
-        reduce_vars : true
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+        unused: true,
     };
     input: {
         function f0() {
             var a = [1, 2, 3];
-            for (var i = 0; i < a.length; i++) {
-                console.log(a[i]);
-            }
+            var b = 0;
+            for (var i = 0; i < a.length; i++)
+                b += a[i];
+            return b;
         }
-
         function f1() {
             var a = [1, 2, 3];
-            for (var i = 0, len = a.length; i < len; i++) {
-                console.log(a[i]);
-            }
+            var b = 0;
+            for (var i = 0, len = a.length; i < len; i++)
+                b += a[i];
+            return b;
         }
-
-        function f2() {
-            var a = [1, 2, 3];
-            for (var i = 0; i < a.length; i++) {
-                a[i]++;
-            }
-        }
-    }
-    expect: {
-        function f0() {
-            var a = [1, 2, 3];
-            for (var i = 0; i < 3; i++)
-                console.log(a[i]);
-        }
-
-        function f1() {
-            var a = [1, 2, 3];
-            for (var i = 0; i < 3; i++)
-                console.log(a[i]);
-        }
-
         function f2() {
             var a = [1, 2, 3];
             for (var i = 0; i < a.length; i++)
                 a[i]++;
+            return a[2];
         }
+        console.log(f0(), f1(), f2());
     }
+    expect: {
+        function f0() {
+            var a = [1, 2, 3];
+            var b = 0;
+            for (var i = 0; i < 3; i++)
+                b += a[i];
+            return b;
+        }
+        function f1() {
+            var a = [1, 2, 3];
+            var b = 0;
+            for (var i = 0; i < 3; i++)
+                b += a[i];
+            return b;
+        }
+        function f2() {
+            var a = [1, 2, 3];
+            for (var i = 0; i < a.length; i++)
+                a[i]++;
+            return a[2];
+        }
+        console.log(f0(), f1(), f2());
+    }
+    expect_stdout: "6 6 4"
+}
+
+index: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var a = [ 1, 2 ];
+        console.log(a[0], a[1]);
+    }
+    expect: {
+        console.log(1, 2);
+    }
+    expect_stdout: "1 2"
+}
+
+length: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var a = [ 1, 2 ];
+        console.log(a.length);
+    }
+    expect: {
+        console.log(2);
+    }
+    expect_stdout: "2"
+}
+
+index_length: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var a = [ 1, 2 ];
+        console.log(a[0], a.length);
+    }
+    expect: {
+        console.log(1, 2);
+    }
+    expect_stdout: "1 2"
 }

test/compress/collapse_vars.js

@@ -2051,7 +2051,7 @@ inner_lvalues: {
         console.log(null, a, b);
     }
     expect: {
-        var a, b = 10;
+        var b = 10;
         var a = (--b || a || 3).toString(), c = --b + -a;
         console.log(null, a, b);
     }
@@ -2534,69 +2534,484 @@ issue_2319_3: {
     expect_stdout: "true"
 }
 
-prop_side_effects_1: {
+issue_2365: {
     options = {
         collapse_vars: true,
-        evaluate: true,
-        pure_getters: "strict",
-        reduce_vars: true,
-        toplevel: true,
-        unsafe: true,
-        unused: true,
+        pure_getters: true,
     }
     input: {
-        var C = 1;
-        console.log(C);
-        var obj = {
-            bar: function() {
-                return C + C;
+        console.log(function(a) {
+            var b = a.f;
+            a.f++;
+            return b;
+        }({ f: 1 }));
+        console.log(function() {
+            var a = { f: 1 }, b = a.f;
+            a.f++;
+            return b;
+        }());
+        console.log({
+            f: 1,
+            g: function() {
+                var b = this.f;
+                this.f++;
+                return b;
             }
-        };
-        console.log(obj.bar());
+        }.g());
     }
     expect: {
-        console.log(1);
+        console.log(function(a) {
+            var b = a.f;
+            a.f++;
+            return b;
+        }({ f: 1 }));
+        console.log(function() {
+            var a = { f: 1 }, b = a.f;
+            a.f++;
+            return b;
+        }());
         console.log({
-            bar: function() {
-                return 2;
+            f: 1,
+            g: function() {
+                var b = this.f;
+                this.f++;
+                return b;
             }
-        }.bar());
+        }.g());
     }
     expect_stdout: [
         "1",
-        "2",
+        "1",
+        "1",
     ]
 }
 
-prop_side_effects_2: {
+issue_2364_1: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        function inc(obj) {
+            return obj.count++;
+        }
+        function foo() {
+            var first = arguments[0];
+            var result = inc(first);
+            return foo.amount = first.count, result;
+        }
+        var data = {
+            count: 0,
+        };
+        var answer = foo(data);
+        console.log(foo.amount, answer);
+    }
+    expect: {
+        function inc(obj) {
+            return obj.count++;
+        }
+        function foo() {
+            var first = arguments[0];
+            var result = inc(first);
+            return foo.amount = first.count, result;
+        }
+        var data = {
+            count: 0
+        };
+        var answer = foo(data);
+        console.log(foo.amount, answer);
+    }
+    expect_stdout: "1 0"
+}
+
+issue_2364_2: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        function callValidate() {
+            var validate = compilation.validate;
+            var result = validate.apply(null, arguments);
+            return callValidate.errors = validate.errors, result;
+        }
+    }
+    expect: {
+        function callValidate() {
+            var validate = compilation.validate;
+            var result = validate.apply(null, arguments);
+            return callValidate.errors = validate.errors, result;
+        }
+    }
+}
+
+issue_2364_3: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        function inc(obj) {
+            return obj.count++;
+        }
+        function foo(bar) {
+            var result = inc(bar);
+            return foo.amount = bar.count, result;
+        }
+        var data = {
+            count: 0,
+        };
+        var answer = foo(data);
+        console.log(foo.amount, answer);
+    }
+    expect: {
+        function inc(obj) {
+            return obj.count++;
+        }
+        function foo(bar) {
+            var result = inc(bar);
+            return foo.amount = bar.count, result;
+        }
+        var data = {
+            count: 0,
+        };
+        var answer = foo(data);
+        console.log(foo.amount, answer);
+    }
+    expect_stdout: "1 0"
+}
+
+issue_2364_4: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        function inc(obj) {
+            return obj.count++;
+        }
+        function foo(bar, baz) {
+            var result = inc(bar);
+            return foo.amount = baz.count, result;
+        }
+        var data = {
+            count: 0,
+        };
+        var answer = foo(data, data);
+        console.log(foo.amount, answer);
+    }
+    expect: {
+        function inc(obj) {
+            return obj.count++;
+        }
+        function foo(bar, baz) {
+            var result = inc(bar);
+            return foo.amount = baz.count, result;
+        }
+        var data = {
+            count: 0,
+        };
+        var answer = foo(data, data);
+        console.log(foo.amount, answer);
+    }
+    expect_stdout: "1 0"
+}
+
+issue_2364_5: {
     options = {
         collapse_vars: true,
         evaluate: true,
-        inline: true,
-        passes: 2,
-        pure_getters: "strict",
+        pure_getters: true,
+        properties: true,
         reduce_vars: true,
-        side_effects: true,
-        toplevel: true,
-        unsafe: true,
         unused: true,
     }
     input: {
-        var C = 1;
-        console.log(C);
-        var obj = {
-            bar: function() {
-                return C + C;
-            }
-        };
-        console.log(obj.bar());
+        function f0(o, a, h) {
+            var b = 3 - a;
+            var obj = o;
+            var seven = 7;
+            var prop = 'run';
+            var t = obj[prop](b)[seven] = h;
+            return t;
+        }
     }
     expect: {
-        console.log(1);
-        console.log(2);
+        function f0(o, a, h) {
+            return o.run(3 - a)[7] = h;
+        }
     }
-    expect_stdout: [
-        "1",
-        "2",
-    ]
+}
+
+issue_2364_6: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        function f(a, b) {
+            var c = a.p;
+            b.p = "FAIL";
+            return c;
+        }
+        var o = {
+            p: "PASS"
+        }
+        console.log(f(o, o));
+    }
+    expect: {
+        function f(a, b) {
+            var c = a.p;
+            b.p = "FAIL";
+            return c;
+        }
+        var o = {
+            p: "PASS"
+        }
+        console.log(f(o, o));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_2364_7: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        function f(a, b) {
+            var c = a.p;
+            b.f();
+            return c;
+        }
+        var o = {
+            p: "PASS",
+            f: function() {
+                this.p = "FAIL";
+            }
+        }
+        console.log(f(o, o));
+    }
+    expect: {
+        function f(a, b) {
+            var c = a.p;
+            b.f();
+            return c;
+        }
+        var o = {
+            p: "PASS",
+            f: function() {
+                this.p = "FAIL";
+            }
+        }
+        console.log(f(o, o));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_2364_8: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        function f(a, b, c) {
+            var d = a[b.f = function() {
+                return "PASS";
+            }];
+            return c.f(d);
+        }
+        var o = {
+            f: function() {
+                return "FAIL";
+            }
+        };
+        console.log(f({}, o, o));
+    }
+    expect: {
+        function f(a, b, c) {
+            var d = a[b.f = function() {
+                return "PASS";
+            }];
+            return c.f(d);
+        }
+        var o = {
+            f: function() {
+                return "FAIL";
+            }
+        };
+        console.log(f({}, o, o));
+    }
+    expect_stdout: "PASS"
+}
+
+issue_2364_9: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        function f(a, b) {
+            var d = a();
+            return b.f(d);
+        }
+        var o = {
+            f: function() {
+                return "FAIL";
+            }
+        };
+        console.log(f(function() {
+            o.f = function() {
+                return "PASS";
+            };
+        }, o));
+    }
+    expect: {
+        function f(a, b) {
+            var d = a();
+            return b.f(d);
+        }
+        var o = {
+            f: function() {
+                return "FAIL";
+            }
+        };
+        console.log(f(function() {
+            o.f = function() {
+                return "PASS";
+            };
+        }, o));
+    }
+    expect_stdout: "PASS"
+}
+
+pure_getters_chain: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        function o(t, r) {
+            var a = t[1], s = t[2], o = t[3], i = t[5];
+            return a <= 23 && s <= 59 && o <= 59 && (!r || i);
+        }
+        console.log(o([ , 23, 59, 59, , 42], 1));
+    }
+    expect: {
+        function o(t, r) {
+            return t[1] <= 23 && t[2] <= 59 && t[3] <= 59 && (!r || t[5]);
+        }
+        console.log(o([ , 23, 59, 59, , 42], 1));
+    }
+    expect_stdout: "42"
+}
+
+conditional_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function f(a, b) {
+            var c = "";
+            var d = b ? ">" : "<";
+            if (a) c += "=";
+            return c += d;
+        }
+        console.log(f(0, 0), f(0, 1), f(1, 0), f(1, 1));
+    }
+    expect: {
+        function f(a, b) {
+            var c = "";
+            if (a) c += "=";
+            return c += b ? ">" : "<";
+        }
+        console.log(f(0, 0), f(0, 1), f(1, 0), f(1, 1));
+    }
+    expect_stdout: "< > =< =>"
+}
+
+conditional_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function f(a, b) {
+            var c = a + 1, d = a + 2;
+            return b ? c : d;
+        }
+        console.log(f(3, 0), f(4, 1));
+    }
+    expect: {
+        function f(a, b) {
+            return b ? a + 1 : a + 2;
+        }
+        console.log(f(3, 0), f(4, 1));
+    }
+    expect_stdout: "5 5"
+}
+
+issue_2425_1: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = 8;
+        (function(b) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect: {
+        var a = 8;
+        (function(b) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect_stdout: "15"
+}
+
+issue_2425_2: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = 8;
+        (function(b, c) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect: {
+        var a = 8;
+        (function(b, c) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect_stdout: "15"
+}
+
+issue_2425_3: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = 8;
+        (function(b, b) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect: {
+        var a = 8;
+        (function(b, b) {
+            (a |= 10).toString();
+        })(--a);
+        console.log(a);
+    }
+    expect_stdout: "15"
 }

test/compress/comparing.js

@@ -73,4 +73,41 @@ dont_change_in_or_instanceof_expressions: {
         1 instanceof 1;
         null instanceof null;
     }
-}
+}
+
+self_comparison_1: {
+    options = {
+        comparisons: true,
+    }
+    input: {
+        a === a;
+        a !== b;
+        b.c === a.c;
+        b.c !== b.c;
+    }
+    expect: {
+        a == a;
+        a !== b;
+        b.c === a.c;
+        b.c != b.c;
+    }
+}
+
+self_comparison_2: {
+    options = {
+        comparisons: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        function f() {}
+        var o = {};
+        console.log(f != f, o === o);
+    }
+    expect: {
+        function f() {}
+        var o = {};
+        console.log(false, true);
+    }
+    expect_stdout: "false true"
+}

test/compress/drop-unused.js

@@ -1109,11 +1109,11 @@ var_catch_toplevel: {
     }
 }
 
-issue_2105: {
+issue_2105_1: {
     options = {
         collapse_vars: true,
         inline: true,
-        passes: 3,
+        passes: 2,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -1139,17 +1139,50 @@ issue_2105: {
         });
     }
     expect: {
-        (function() {
-            var quux = function() {
+        ({
+            prop: function() {
+                console.log;
                 console.log("PASS");
-            };
-            return {
-                prop: function() {
-                    console.log;
-                    quux();
+            }
+        }).prop();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_2105_2: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        passes: 2,
+        properties: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        !function(factory) {
+            factory();
+        }( function() {
+            return function(fn) {
+                fn()().prop();
+            }( function() {
+                function bar() {
+                    var quux = function() {
+                        console.log("PASS");
+                    }, foo = function() {
+                        console.log;
+                        quux();
+                    };
+                    return { prop: foo };
                 }
-            };
-        })().prop();
+                return bar;
+            } );
+        });
+    }
+    expect: {
+        console.log("PASS");
     }
     expect_stdout: "PASS"
 }

test/compress/evaluate.js

@@ -386,10 +386,11 @@ unsafe_object_accessor: {
     }
 }
 
-unsafe_function: {
+prop_function: {
     options = {
-        evaluate  : true,
-        unsafe    : true
+        evaluate: true,
+        properties: true,
+        side_effects: true,
     }
     input: {
         console.log(
@@ -402,9 +403,9 @@ unsafe_function: {
     expect: {
         console.log(
             ({a:{b:1},b:function(){}}) + 1,
-            ({b:function(){}}, {b:1}) + 1,
-            ({a:{b:1}}, function(){}) + 1,
-            ({b:function(){}}, {b:1}).b + 1
+            ({b:1}) + 1,
+            function(){} + 1,
+            2
         );
     }
     expect_stdout: true
@@ -630,10 +631,11 @@ unsafe_string_bad_index: {
     expect_stdout: true
 }
 
-unsafe_prototype_function: {
+prototype_function: {
     options = {
-        evaluate  : true,
-        unsafe    : true
+        evaluate: true,
+        properties: true,
+        side_effects: true,
     }
     input: {
         var a = ({valueOf: 0}) < 1;
@@ -652,8 +654,8 @@ unsafe_prototype_function: {
         var d = ({toString: 0}) + "";
         var e = (({valueOf: 0}) + "")[2];
         var f = (({toString: 0}) + "")[2];
-        var g = ({}, 0)();
-        var h = ({}, 0)();
+        var g = 0();
+        var h = 0();
     }
 }
 
@@ -1195,3 +1197,40 @@ issue_2231_2: {
     }
     expect_stdout: true
 }
+
+self_comparison_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var o = { n: NaN };
+        console.log(o.n == o.n, o.n === o.n, o.n != o.n, o.n !== o.n, typeof o.n);
+    }
+    expect: {
+        console.log(false, false, true, true, "number");
+    }
+    expect_stdout: "false false true true 'number'"
+}
+
+self_comparison_2: {
+    options = {
+        evaluate: true,
+        hoist_props: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = { n: NaN };
+        console.log(o.n == o.n, o.n === o.n, o.n != o.n, o.n !== o.n, typeof o.n);
+    }
+    expect: {
+        console.log(false, false, true, true, "number");
+    }
+    expect_stdout: "false false true true 'number'"
+}

test/compress/functions.js

@@ -151,13 +151,13 @@ issue_1841_2: {
 
 function_returning_constant_literal: {
     options = {
-        reduce_vars: true,
-        unsafe: true,
-        toplevel: true,
-        evaluate: true,
-        cascade: true,
-        unused: true,
         inline: true,
+        passes: 2,
+        properties: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
     }
     input: {
         function greeter() {

test/compress/hoist_props.js

@@ -0,0 +1,399 @@
+issue_2377_1: {
+    options = {
+        evaluate: true,
+        inline: true,
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var obj = {
+            foo: 1,
+            bar: 2,
+            square: function(x) {
+                return x * x;
+            },
+            cube: function(x) {
+                return x * x * x;
+            },
+        };
+        console.log(obj.foo, obj.cube(3));
+    }
+    expect: {
+        var obj_foo = 1, obj_cube = function(x) {
+            return x * x * x;
+        };
+        console.log(obj_foo, obj_cube(3));
+    }
+    expect_stdout: "1 27"
+}
+
+issue_2377_2: {
+    options = {
+        evaluate: true,
+        inline: true,
+        hoist_props: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var obj = {
+            foo: 1,
+            bar: 2,
+            square: function(x) {
+                return x * x;
+            },
+            cube: function(x) {
+                return x * x * x;
+            },
+        };
+        console.log(obj.foo, obj.cube(3));
+    }
+    expect: {
+        console.log(1, function(x) {
+            return x * x * x;
+        }(3));
+    }
+    expect_stdout: "1 27"
+}
+
+issue_2377_3: {
+    options = {
+        evaluate: true,
+        inline: true,
+        hoist_props: true,
+        passes: 3,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var obj = {
+            foo: 1,
+            bar: 2,
+            square: function(x) {
+                return x * x;
+            },
+            cube: function(x) {
+                return x * x * x;
+            },
+        };
+        console.log(obj.foo, obj.cube(3));
+    }
+    expect: {
+        console.log(1, 27);
+    }
+    expect_stdout: "1 27"
+}
+
+direct_access_1: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var a = 0;
+        var obj = {
+            a: 1,
+            b: 2,
+        };
+        for (var k in obj) a++;
+        console.log(a, obj.a);
+    }
+    expect: {
+        var a = 0;
+        var obj = {
+            a: 1,
+            b: 2,
+        };
+        for (var k in obj) a++;
+        console.log(a, obj.a);
+    }
+    expect_stdout: "2 1"
+}
+
+direct_access_2: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = { a: 1 };
+        var f = function(k) {
+            if (o[k]) return "PASS";
+        };
+        console.log(f("a"));
+    }
+    expect: {
+        var o = { a: 1 };
+        console.log(function(k) {
+            if (o[k]) return "PASS";
+        }("a"));
+    }
+    expect_stdout: "PASS"
+}
+
+direct_access_3: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = { a: 1 };
+        o.b;
+        console.log(o.a);
+    }
+    expect: {
+        var o = { a: 1 };
+        o.b;
+        console.log(o.a);
+    }
+    expect_stdout: "1"
+}
+
+single_use: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var obj = {
+            bar: function() {
+                return 42;
+            },
+        };
+        console.log(obj.bar());
+    }
+    expect: {
+        console.log({
+            bar: function() {
+                return 42;
+            },
+        }.bar());
+    }
+}
+
+name_collision_1: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var obj_foo = 1;
+        var obj_bar = 2;
+        function f() {
+            var obj = {
+                foo: 3,
+                bar: 4,
+                "b-r": 5,
+                "b+r": 6,
+                "b!r": 7,
+            };
+            console.log(obj_foo, obj.foo, obj.bar, obj["b-r"], obj["b+r"], obj["b!r"]);
+        }
+        f();
+    }
+    expect: {
+        var obj_foo = 1;
+        var obj_bar = 2;
+        function f() {
+            var obj_foo$0 = 3,
+                obj_bar = 4,
+                obj_b_r = 5,
+                obj_b_r$0 = 6,
+                obj_b_r$1 = 7;
+            console.log(obj_foo, obj_foo$0, obj_bar, obj_b_r, obj_b_r$0, obj_b_r$1);
+        }
+        f();
+    }
+    expect_stdout: "1 3 4 5 6 7"
+}
+
+name_collision_2: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var o = {
+            p: 1,
+            0: function(x) {
+                return x;
+            },
+            1: function(x) {
+                return x + 1;
+            }
+        }, o__$0 = 2, o__$1 = 3;
+        console.log(o.p === o.p, o[0](4), o[1](5), o__$0, o__$1);
+    }
+    expect: {
+        var o_p = 1,
+            o__ = function(x) {
+                return x;
+            },
+            o__$2 = function(x) {
+                return x + 1;
+            },
+            o__$0 = 2,
+            o__$1 = 3;
+        console.log(o_p === o_p, o__(4), o__$2(5), o__$0, o__$1);
+    }
+    expect_stdout: "true 4 6 2 3"
+}
+
+name_collision_3: {
+    options = {
+        hoist_props: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var o = {
+            p: 1,
+            0: function(x) {
+                return x;
+            },
+            1: function(x) {
+                return x + 1;
+            }
+        }, o__$0 = 2, o__$1 = 3;
+        console.log(o.p === o.p, o[0](4), o[1](5));
+    }
+    expect: {
+        var o_p = 1,
+            o__ = function(x) {
+                return x;
+            },
+            o__$2 = function(x) {
+                return x + 1;
+            },
+            o__$0 = 2,
+            o__$1 = 3;
+        console.log(o_p === o_p, o__(4), o__$2(5));
+    }
+    expect_stdout: "true 4 6"
+}
+
+contains_this_1: {
+    options = {
+        evaluate: true,
+        hoist_props: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            u: function() {
+                return this === this;
+            },
+            p: 1
+        };
+        console.log(o.p, o.p);
+    }
+    expect: {
+        console.log(1, 1);
+    }
+    expect_stdout: "1 1"
+}
+
+contains_this_2: {
+    options = {
+        evaluate: true,
+        hoist_props: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            u: function() {
+                return this === this;
+            },
+            p: 1
+        };
+        console.log(o.p, o.p, o.u);
+    }
+    expect: {
+        console.log(1, 1, function() {
+            return this === this;
+        });
+    }
+    expect_stdout: true
+}
+
+contains_this_3: {
+    options = {
+        evaluate: true,
+        hoist_props: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            u: function() {
+                return this === this;
+            },
+            p: 1
+        };
+        console.log(o.p, o.p, o.u());
+    }
+    expect: {
+        var o = {
+            u: function() {
+                return this === this;
+            },
+            p: 1
+        };
+        console.log(o.p, o.p, o.u());
+    }
+    expect_stdout: "1 1 true"
+}
+
+new_this: {
+    options = {
+        evaluate: true,
+        hoist_props: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            a: 1,
+            b: 2,
+            f: function(a) {
+                this.b = a;
+            }
+        };
+        console.log(new o.f(o.a).b, o.b);
+    }
+    expect: {
+        console.log(new function(a) {
+            this.b = a;
+        }(1).b, 2);
+    }
+    expect_stdout: "1 2"
+}

test/compress/properties.js

@@ -1,7 +1,8 @@
 keep_properties: {
     options = {
-        properties: false
-    };
+        evaluate: true,
+        properties: false,
+    }
     input: {
         a["foo"] = "bar";
     }
@@ -12,6 +13,7 @@ keep_properties: {
 
 dot_properties: {
     options = {
+        evaluate: true,
         properties: true,
     }
     beautify = {
@@ -37,6 +39,7 @@ dot_properties: {
 
 dot_properties_es5: {
     options = {
+        evaluate: true,
         properties: true,
     }
     beautify = {
@@ -61,8 +64,8 @@ dot_properties_es5: {
 sub_properties: {
     options = {
         evaluate: true,
-        properties: true
-    };
+        properties: true,
+    }
     input: {
         a[0] = 0;
         a["0"] = 1;
@@ -81,18 +84,18 @@ sub_properties: {
         a[3.14] = 3;
         a.if = 4;
         a["foo bar"] = 5;
-        a[NaN] = 6;
-        a[null] = 7;
+        a.NaN = 6;
+        a.null = 7;
         a[void 0] = 8;
     }
 }
 
 evaluate_array_length: {
     options = {
+        evaluate: true,
         properties: true,
         unsafe: true,
-        evaluate: true
-    };
+    }
     input: {
         a = [1, 2, 3].length;
         a = [1, 2, 3].join()["len" + "gth"];
@@ -109,10 +112,10 @@ evaluate_array_length: {
 
 evaluate_string_length: {
     options = {
+        evaluate: true,
         properties: true,
         unsafe: true,
-        evaluate: true
-    };
+    }
     input: {
         a = "foo".length;
         a = ("foo" + "bar")["len" + "gth"];
@@ -151,7 +154,8 @@ mangle_properties: {
 
 mangle_unquoted_properties: {
     options = {
-        properties: false
+        evaluate: true,
+        properties: false,
     }
     mangle = {
         properties: {
@@ -249,7 +253,8 @@ mangle_debug_suffix: {
 
 mangle_debug_suffix_keep_quoted: {
     options = {
-        properties: false
+        evaluate: true,
+        properties: false,
     }
     mangle = {
         properties: {
@@ -677,8 +682,8 @@ accessor_this: {
 issue_2208_1: {
     options = {
         inline: true,
+        properties: true,
         side_effects: true,
-        unsafe: true,
     }
     input: {
         console.log({
@@ -696,8 +701,8 @@ issue_2208_1: {
 issue_2208_2: {
     options = {
         inline: true,
+        properties: true,
         side_effects: true,
-        unsafe: true,
     }
     input: {
         console.log({
@@ -721,8 +726,8 @@ issue_2208_2: {
 issue_2208_3: {
     options = {
         inline: true,
+        properties: true,
         side_effects: true,
-        unsafe: true,
     }
     input: {
         a = 42;
@@ -746,8 +751,8 @@ issue_2208_3: {
 issue_2208_4: {
     options = {
         inline: true,
+        properties: true,
         side_effects: true,
-        unsafe: true,
     }
     input: {
         function foo() {}
@@ -770,8 +775,8 @@ issue_2208_4: {
 issue_2208_5: {
     options = {
         inline: true,
+        properties: true,
         side_effects: true,
-        unsafe: true,
     }
     input: {
         console.log({
@@ -804,3 +809,219 @@ issue_2256: {
         g.keep = g.g;
     }
 }
+
+lhs_prop_1: {
+    options = {
+        evaluate: true,
+        properties: true,
+    }
+    input: {
+        console.log(++{
+            a: 1
+        }.a);
+    }
+    expect: {
+        console.log(++{
+            a: 1
+        }.a);
+    }
+    expect_stdout: "2"
+}
+
+lhs_prop_2: {
+    options = {
+        evaluate: true,
+        inline: true,
+        properties: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        [1][0] = 42;
+        (function(a) {
+            a.b = "g";
+        })("abc");
+        (function(a) {
+            a[2] = "g";
+        })("def");
+        (function(a) {
+            a[""] = "g";
+        })("ghi");
+    }
+    expect: {
+        [1][0] = 42;
+        "abc".b = "g";
+        "def"[2] = "g";
+        "ghi"[""] = "g";
+    }
+}
+
+literal_duplicate_key_side_effects: {
+    options = {
+        properties: true,
+        side_effects: true,
+    }
+    input: {
+        console.log({
+            a: "FAIL",
+            a: console.log ? "PASS" : "FAIL"
+        }.a);
+    }
+    expect: {
+        console.log(console.log ? "PASS" : "FAIL");
+    }
+    expect_stdout: "PASS"
+}
+
+prop_side_effects_1: {
+    options = {
+        evaluate: true,
+        inline: true,
+        properties: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var C = 1;
+        console.log(C);
+        var obj = {
+            bar: function() {
+                return C + C;
+            }
+        };
+        console.log(obj.bar());
+    }
+    expect: {
+        console.log(1);
+        var obj = {
+            bar: function() {
+                return 2;
+            }
+        };
+        console.log(obj.bar());
+    }
+    expect_stdout: [
+        "1",
+        "2",
+    ]
+}
+
+prop_side_effects_2: {
+    options = {
+        evaluate: true,
+        inline: true,
+        passes: 2,
+        properties: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var C = 1;
+        console.log(C);
+        var obj = {
+            "": function() {
+                return C + C;
+            }
+        };
+        console.log(obj[""]());
+    }
+    expect: {
+        console.log(1);
+        console.log(2);
+    }
+    expect_stdout: [
+        "1",
+        "2",
+    ]
+}
+
+accessor_1: {
+    options = {
+        properties: true,
+    }
+    input: {
+        console.log({
+            a: "FAIL",
+            get a() {
+                return "PASS";
+            }
+        }.a);
+    }
+    expect: {
+        console.log({
+            a: "FAIL",
+            get a() {
+                return "PASS";
+            }
+        }.a);
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}
+
+accessor_2: {
+    options = {
+        properties: true,
+    }
+    input: {
+        console.log({
+            get a() {
+                return "PASS";
+            },
+            set a(v) {},
+            a: "FAIL"
+        }.a);
+    }
+    expect: {
+        console.log({
+            get a() {
+                return "PASS";
+            },
+            set a(v) {},
+            a: "FAIL"
+        }.a);
+    }
+    expect_stdout: true
+}
+
+array_hole: {
+    options = {
+        properties: true,
+        side_effects: true,
+    }
+    input: {
+        console.log(
+            [ 1, 2, , 3][1],
+            [ 1, 2, , 3][2],
+            [ 1, 2, , 3][3]
+        );
+    }
+    expect: {
+        console.log(2, void 0, 3);
+    }
+    expect_stdout: "2 undefined 3"
+}
+
+new_this: {
+    options = {
+        properties: true,
+        side_effects: true,
+    }
+    input: {
+        new {
+            f: function(a) {
+                this.a = a;
+            }
+        }.f(42);
+    }
+    expect: {
+        new function(a) {
+            this.a = a;
+        }(42);
+    }
+}

test/compress/reduce_vars.js

@@ -211,7 +211,116 @@ unsafe_evaluate: {
     }
 }
 
-unsafe_evaluate_object: {
+unsafe_evaluate_side_effect_free_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(){ var o={p:1}; console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:2}; console.log(o.p); return o; }());
+        console.log(function(){ var o={p:3}; console.log([o][0].p); return o.p; }());
+    }
+    expect: {
+        console.log(function(){ console.log(1); return 1; }());
+        console.log(function(){ var o={p:2}; console.log(2); return o; }());
+        console.log(function(){ console.log(3); return 3; }());
+    }
+    expect_stdout: true
+}
+
+unsafe_evaluate_side_effect_free_2: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        passes: 2,
+        pure_getters: "strict",
+        reduce_vars: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(){ var o={p:1},a=[o]; console.log(a[0].p); return o.p; }());
+    }
+    expect: {
+        console.log(function(){ console.log(1); return 1; }());
+    }
+    expect_stdout: true
+}
+
+unsafe_evaluate_escaped: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(){ var o={p:1}; console.log(o, o.p); return o.p; }());
+        console.log(function(){ var o={p:2}; console.log(o.p, o); return o.p; }());
+        console.log(function(){ var o={p:3},a=[o]; console.log(a[0].p++); return o.p; }());
+    }
+    expect: {
+        console.log(function(){ var o={p:1}; console.log(o, o.p); return o.p; }());
+        console.log(function(){ var o={p:2}; console.log(o.p, o); return o.p; }());
+        console.log(function(){ var o={p:3},a=[o]; console.log(a[0].p++); return o.p; }());
+    }
+    expect_stdout: true
+}
+
+unsafe_evaluate_modified: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(){ var o={p:1}; o.p++; console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:2}; --o.p; console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:3}; o.p += ""; console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:4}; o = {}; console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:5}; o.p = -9; console.log(o.p); return o.p; }());
+        function inc() { this.p++; }
+        console.log(function(){ var o={p:6}; inc.call(o); console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:7}; console.log([o][0].p++); return o.p; }());
+    }
+    expect: {
+        console.log(function(){ var o={p:1}; o.p++; console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:2}; --o.p; console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:3}; o.p += ""; console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:4}; o = {}; console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:5}; o.p = -9; console.log(o.p); return o.p; }());
+        function inc() { this.p++; }
+        console.log(function(){ var o={p:6}; inc.call(o); console.log(o.p); return o.p; }());
+        console.log(function(){ var o={p:7}; console.log([o][0].p++); return o.p; }());
+    }
+    expect_stdout: true
+}
+
+unsafe_evaluate_unknown: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(){ var o={p:1}; console.log(o.not_present); return o.p; }());
+        console.log(function(){ var o={p:2}; console.log(o.prototype); return o.p; }());
+        console.log(function(){ var o={p:3}; console.log(o.hasOwnProperty); return o.p; }());
+    }
+    expect: {
+        console.log(function(){ var o={p:1}; console.log(o.not_present); return o.p; }());
+        console.log(function(){ var o={p:2}; console.log(o.prototype); return o.p; }());
+        console.log(function(){ var o={p:3}; console.log(o.hasOwnProperty); return o.p; }());
+    }
+    expect_stdout: true
+}
+
+unsafe_evaluate_object_1: {
     options = {
         evaluate     : true,
         reduce_vars  : true,
@@ -251,7 +360,83 @@ unsafe_evaluate_object: {
     }
 }
 
-unsafe_evaluate_array: {
+unsafe_evaluate_object_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var obj = {
+            foo: 1,
+            bar: 2,
+            square: function(x) {
+                return x * x;
+            },
+            cube: function(x) {
+                return x * x * x;
+            },
+        };
+        console.log(obj.foo, obj.bar, obj.square(2), obj.cube);
+    }
+    expect: {
+        var obj = {
+            foo: 1,
+            bar: 2,
+            square: function(x) {
+                return x * x;
+            },
+            cube: function(x) {
+                return x * x * x;
+            },
+        };
+        console.log(1, 2, obj.square(2), obj.cube);
+    }
+    expect_stdout: true
+}
+
+unsafe_evaluate_object_3: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var obj = {
+            get foo() {
+                return 1;
+            },
+            bar: 2,
+            square: function(x) {
+                return x * x;
+            },
+            cube: function(x) {
+                return x * x * x;
+            },
+        };
+        console.log(obj.foo, obj.bar, obj.square(2), obj.cube);
+    }
+    expect: {
+        var obj = {
+            get foo() {
+                return 1;
+            },
+            bar: 2,
+            square: function(x) {
+                return x * x;
+            },
+            cube: function(x) {
+                return x * x * x;
+            },
+        };
+        console.log(obj.foo, obj.bar, obj.square(2), obj.cube);
+    }
+    expect_stdout: true
+}
+
+unsafe_evaluate_array_1: {
     options = {
         evaluate     : true,
         reduce_vars  : true,
@@ -299,6 +484,132 @@ unsafe_evaluate_array: {
     }
 }
 
+unsafe_evaluate_array_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var arr = [
+            1,
+            2,
+            function(x) {
+                return x * x;
+            },
+            function(x) {
+                return x * x * x;
+            },
+        ];
+        console.log(arr[0], arr[1], arr[2](2), arr[3]);
+    }
+    expect: {
+        var arr = [
+            1,
+            2,
+            function(x) {
+                return x * x;
+            },
+            function(x) {
+                return x * x * x;
+            },
+        ];
+        console.log(1, 2, arr[2](2), arr[3]);
+    }
+    expect_stdout: true
+}
+
+unsafe_evaluate_array_3: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var arr = [
+            1,
+            2,
+            function() {
+                return ++arr[0];
+            },
+        ];
+        console.log(arr[0], arr[1], arr[2](), arr[0]);
+    }
+    expect: {
+        var arr = [
+            1,
+            2,
+            function() {
+                return ++arr[0];
+            },
+        ];
+        console.log(arr[0], arr[1], arr[2](), arr[0]);
+    }
+    expect_stdout: "1 2 2 2"
+}
+
+unsafe_evaluate_array_4: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var arr = [
+            1,
+            2,
+            function() {
+                return ++this[0];
+            },
+        ];
+        console.log(arr[0], arr[1], arr[2], arr[0]);
+    }
+    expect: {
+        var arr = [
+            1,
+            2,
+            function() {
+                return ++this[0];
+            },
+        ];
+        console.log(1, 2, arr[2], 1);
+    }
+    expect_stdout: true
+}
+
+unsafe_evaluate_array_5: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var arr = [
+            1,
+            2,
+            function() {
+                return ++this[0];
+            },
+        ];
+        console.log(arr[0], arr[1], arr[2](), arr[0]);
+    }
+    expect: {
+        var arr = [
+            1,
+            2,
+            function() {
+                return ++this[0];
+            },
+        ];
+        console.log(arr[0], arr[1], arr[2](), arr[0]);
+    }
+    expect_stdout: "1 2 2 2"
+}
+
 unsafe_evaluate_equality_1: {
     options = {
         evaluate     : true,
@@ -1190,10 +1501,10 @@ defun_label: {
         !function() {
             console.log(function(a) {
                 L: {
-                    if (a) break L;
+                    if (2) break L;
                     return 1;
                 }
-            }(2));
+            }());
         }();
     }
     expect_stdout: true
@@ -2660,6 +2971,7 @@ obj_var_2: {
         evaluate: true,
         inline: true,
         passes: 2,
+        properties: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -2716,10 +3028,10 @@ obj_arg_2: {
         evaluate: true,
         inline: true,
         passes: 2,
+        properties: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
-        unsafe: true,
         unused: true,
     }
     input: {
@@ -2894,3 +3206,339 @@ array_forin_2: {
     }
     expect_stdout: "3"
 }
+
+const_expr_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            a: 1,
+            b: 2
+        };
+        o.a++;
+        console.log(o.a, o.b);
+    }
+    expect: {
+        var o = {
+            a: 1,
+            b: 2
+        };
+        o.a++;
+        console.log(o.a, o.b);
+    }
+    expect_stdout: "2 2"
+}
+
+const_expr_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        Object.prototype.c = function() {
+            this.a++;
+        };
+        var o = {
+            a: 1,
+            b: 2
+        };
+        o.c();
+        console.log(o.a, o.b);
+    }
+    expect: {
+        Object.prototype.c = function() {
+            this.a++;
+        };
+        var o = {
+            a: 1,
+            b: 2
+        };
+        o.c();
+        console.log(o.a, o.b);
+    }
+    expect_stdout: "2 2"
+}
+
+escaped_prop: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var obj = { o: { a: 1 } };
+        (function(o) {
+            o.a++;
+        })(obj.o);
+        (function(o) {
+            console.log(o.a);
+        })(obj.o);
+    }
+    expect: {
+        var obj = { o: { a: 1 } };
+        obj.o.a++;
+        console.log(obj.o.a);
+    }
+    expect_stdout: "2"
+}
+
+issue_2420_1: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function run() {
+            var self = this;
+            if (self.count++)
+                self.foo();
+            else
+                self.bar();
+        }
+        var o = {
+            count: 0,
+            foo: function() { console.log("foo"); },
+            bar: function() { console.log("bar"); },
+        };
+        run.call(o);
+        run.call(o);
+    }
+    expect: {
+        function run() {
+            if (this.count++)
+                this.foo();
+            else
+                this.bar();
+        }
+        var o = {
+            count: 0,
+            foo: function() { console.log("foo"); },
+            bar: function() { console.log("bar"); },
+        };
+        run.call(o);
+        run.call(o);
+    }
+    expect_stdout: [
+        "bar",
+        "foo",
+    ]
+}
+
+issue_2420_2: {
+    options = {
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            var that = this;
+            if (that.bar)
+                that.foo();
+            else
+                !function(that, self) {
+                    console.log(this === that, self === this, that === self);
+                }(that, this);
+        }
+        f.call({
+            bar: 1,
+            foo: function() { console.log("foo", this.bar); },
+        });
+        f.call({});
+    }
+    expect: {
+        function f() {
+            if (this.bar)
+                this.foo();
+            else
+                !function(that, self) {
+                    console.log(this === that, self === this, that === self);
+                }(this, this);
+        }
+        f.call({
+            bar: 1,
+            foo: function() { console.log("foo", this.bar); },
+        });
+        f.call({});
+    }
+    expect_stdout: [
+        "foo 1",
+        "false false true",
+    ]
+}
+
+issue_2423_1: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function c() { return 1; }
+        function p() { console.log(c()); }
+        p();
+        p();
+    }
+    expect: {
+        function p() { console.log(function() { return 1; }()); }
+        p();
+        p();
+    }
+    expect_stdout: [
+        "1",
+        "1",
+    ]
+}
+
+issue_2423_2: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function c() { return 1; }
+        function p() { console.log(c()); }
+        p();
+        p();
+    }
+    expect: {
+        function p() { console.log(1); }
+        p();
+        p();
+    }
+    expect_stdout: [
+        "1",
+        "1",
+    ]
+}
+
+issue_2423_3: {
+    options = {
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function c() { return 1; }
+        function p() { console.log(c()); }
+        p();
+    }
+    expect: {
+        (function() { console.log(function() { return 1; }()); })();
+    }
+    expect_stdout: "1"
+}
+
+issue_2423_4: {
+    options = {
+        inline: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function c() { return 1; }
+        function p() { console.log(c()); }
+        p();
+    }
+    expect: {
+        console.log(1);
+    }
+    expect_stdout: "1"
+}
+
+issue_2423_5: {
+    options = {
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function x() {
+            y();
+        }
+        function y() {
+            console.log(1);
+        }
+        function z() {
+            function y() {
+                console.log(2);
+            }
+            x();
+        }
+        z();
+        z();
+    }
+    expect: {
+        function z() {
+            console.log(1);
+        }
+        z();
+        z();
+    }
+    expect_stdout: [
+        "1",
+        "1",
+    ]
+}
+
+issue_2423_6: {
+    options = {
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function x() {
+            y();
+        }
+        function y() {
+            console.log(1);
+        }
+        function z() {
+            function y() {
+                console.log(2);
+            }
+            x();
+            y();
+        }
+        z();
+        z();
+    }
+    expect: {
+        function z(){
+            console.log(1);
+            console.log(2);
+        }
+        z();
+        z();
+    }
+    expect_stdout: [
+        "1",
+        "2",
+        "1",
+        "2",
+    ]
+}

test/ufuzz.js

@@ -162,6 +162,7 @@ var VALUES = [
     '"object"',
     '"number"',
     '"function"',
+    'this',
 ];
 
 var BINARY_OPS_NO_COMMA = [
@@ -349,10 +350,10 @@ function createParams() {
     return params.join(', ');
 }
 
-function createArgs() {
+function createArgs(recurmax, stmtDepth, canThrow) {
     var args = [];
     for (var n = rng(4); --n >= 0;) {
-        args.push(createValue());
+        args.push(rng(2) ? createValue() : createExpression(recurmax - 1, COMMA_OK, stmtDepth, canThrow));
     }
     return args.join(', ');
 }
@@ -390,9 +391,10 @@ function createFunction(recurmax, inGlobal, noDecl, canThrow, stmtDepth) {
 
     VAR_NAMES.length = namesLenBefore;
 
-    if (noDecl) s = 'var ' + createVarName(MANDATORY) + ' = ' + s + '(' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ');';
+    if (noDecl) s = 'var ' + createVarName(MANDATORY) + ' = ' + s;
     // avoid "function statements" (decl inside statements)
-    else if (inGlobal || rng(10) > 0) s += 'var ' + createVarName(MANDATORY) + ' = ' + name + '(' + createArgs() + ');';
+    else if (inGlobal || rng(10) > 0) s += 'var ' + createVarName(MANDATORY) + ' = ' + name;
+    s += '(' + createArgs(recurmax, stmtDepth, canThrow) + ');';
 
     return s;
 }
@@ -626,6 +628,9 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
       case p++:
       case p++:
         return createValue();
+      case p++:
+      case p++:
+        return getVarName();
       case p++:
         return createExpression(recurmax, COMMA_OK, stmtDepth, canThrow);
       case p++:

test/ufuzz.json

@@ -16,11 +16,9 @@
     {},
     {
         "compress": {
-            "toplevel": true
+            "hoist_props": true
         },
-        "mangle": {
-            "toplevel": true
-        }
+        "toplevel": true
     },
     {
         "compress": {