harmony-v3.1.5

Sub-optimal result due to block scope.

README.md

@@ -604,7 +604,7 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 
 ## Compress options
 
-- `arrows` (default `true`) -- Converts `()=>{return x}` to `()=>x`. Class
+- `arrows` (default: `true`) -- Converts `()=>{return x}` to `()=>x`. Class
   and object literal methods will also be converted to arrow expressions if
   the resultant code is shorter: `m(){return x}` becomes `m:()=>x`.
   This transform requires that the `ecma` compress option is set to `6` or greater.
@@ -622,8 +622,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   `!(a <= b) → a > b` (only when `unsafe_comps`), attempts to negate binary
   nodes, e.g. `a = !b && !c && !d && !e → a=!(b||c||d||e)` etc.
 
-- `computed_props` -- default `true`. Transforms constant computed properties
-  into regular ones: `{["computed"]: 1}` is converted into `{computed: 1}`.
+- `computed_props` (default: `true`) -- Transforms constant computed properties
+  into regular ones: `{["computed"]: 1}` is converted to `{computed: 1}`.
 
 - `conditionals` (default: `true`) -- apply optimizations for `if`-s and conditional
   expressions
@@ -637,7 +637,7 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 
 - `drop_debugger` (default: `true`) -- remove `debugger;` statements
 
-- `ecma` -- default `5`. Pass `6` or greater to enable `compress` options that
+- `ecma` (default: `5`) -- Pass `6` or greater to enable `compress` options that
   will transform ES5 code into smaller ES6+ equivalent forms.
 
 - `evaluate` (default: `true`) -- attempt to evaluate constant expressions
@@ -662,6 +662,10 @@ 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.
 
@@ -726,7 +730,9 @@ 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_arrows` (default `false`) -- Convert ES5 style anonymous function
+- `unsafe` (default: `false`) -- apply "unsafe" transformations (discussion below)
+
+- `unsafe_arrows` (default: `false`) -- Convert ES5 style anonymous function
   expressions to arrow functions if the function body does not reference `this`.
   Note: it is not always safe to perform this conversion if code relies on the
   the function having a `prototype`, which arrow functions lack.
@@ -739,14 +745,19 @@ 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.
 
 - `unsafe_math` (default: `false`) -- optimize numerical expressions like
   `2 * x * 3` into `6 * x`, which may give imprecise floating point results.
 
+- `unsafe_methods` (default: false) -- Converts `{ m: function(){} }` to
+  `{ m(){} }`. `ecma` must be set to `6` or greater to enable this transform.
+  If `unsafe_methods` is a RegExp then key/value pairs with keys matching the
+  RegExp will be converted to concise methods.
+  Note: if enabled there is a risk of getting a "`<method name>` is not a
+  constructor" TypeError should any code try to `new` the former function.
+
 - `unsafe_proto` (default: `false`) -- optimize expressions like
   `Array.prototype.slice.call(a)` into `[].slice.call(a)`
 
@@ -761,17 +772,21 @@ 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_classnames` (default `false`).  Pass `true` to not mangle class names.
 
+- `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.
-
 - `safari10` (default `false`). Pass `true` to work around the Safari 10 loop
   iterator [bug](https://bugs.webkit.org/show_bug.cgi?id=171041)
   "Cannot declare a let variable twice".

lib/ast.js

@@ -1042,7 +1042,7 @@ var AST_This = DEFNODE("This", null, {
 
 var AST_Super = DEFNODE("Super", null, {
     $documentation: "The `super` symbol",
-}, AST_Symbol);
+}, AST_This);
 
 var AST_Constant = DEFNODE("Constant", null, {
     $documentation: "Base class for all constants",

lib/compress.js

@@ -157,7 +157,7 @@ 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;
@@ -289,8 +289,9 @@ merge(Compressor.prototype, {
         self.transform(tt);
     });
 
-    AST_Node.DEFMETHOD("reset_opt_flags", function(compressor, rescan) {
-        var reduce_vars = rescan && compressor.option("reduce_vars");
+    AST_Node.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
@@ -315,9 +316,23 @@ 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 value = node.fixed_value();
+                        if (unused) {
+                            d.single_use = value
+                                && d.references.length == 1
+                                && loop_ids[d.id] === in_loop
+                                && d.scope === node.scope
+                                && value.is_constant_expression();
+                        }
+                        if (is_modified(node, 0, is_immutable(value))) {
+                            if (d.single_use) {
+                                d.single_use = "m";
+                            } else {
+                                d.fixed = false;
+                            }
                         } else {
                             var parent = tw.parent();
                             if (parent instanceof AST_Assign && parent.operator == "=" && node === parent.right
@@ -328,6 +343,7 @@ merge(Compressor.prototype, {
                             }
                         }
                     }
+                }
                 if (node instanceof AST_SymbolCatch) {
                     node.definition().fixed = false;
                 }
@@ -419,8 +435,7 @@ 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);
@@ -567,20 +582,8 @@ merge(Compressor.prototype, {
             def.single_use = undefined;
         }
 
-        function is_immutable(node) {
-            var value = node.fixed_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;
+        function is_immutable(value) {
+            return value && (value.is_constant() || value instanceof AST_Lambda);
         }
 
         function is_modified(node, level, immutable) {
@@ -610,7 +613,6 @@ merge(Compressor.prototype, {
     }
 
     function is_lhs_read_only(lhs) {
-        if (lhs instanceof AST_Super) return true;
         if (lhs instanceof AST_This) return true;
         if (lhs instanceof AST_SymbolRef) return lhs.definition().orig[0] instanceof AST_SymbolLambda;
         if (lhs instanceof AST_PropAccess) {
@@ -819,6 +821,7 @@ 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;
@@ -880,17 +883,18 @@ 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 == "||")
+                            || (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_For
-                            || parent instanceof AST_If) {
+                                    || parent instanceof AST_If)) {
                             if (!(node instanceof AST_Scope)) descend(node, tt);
                             abort = true;
                             return node;
@@ -1003,28 +1007,15 @@ 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) {
+                    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);
                 return lvalues;
@@ -1522,9 +1513,10 @@ 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();
@@ -1596,6 +1588,7 @@ merge(Compressor.prototype, {
         node.DEFMETHOD("is_string", func);
     });
 
+    var lazy_op = makePredicate("&& ||");
     var unary_side_effects = makePredicate("delete ++ --");
 
     function is_lhs(node, parent) {
@@ -2143,7 +2136,6 @@ merge(Compressor.prototype, {
 
         def(AST_EmptyStatement, return_false);
         def(AST_Constant, return_false);
-        def(AST_Super, return_false);
         def(AST_This, return_false);
 
         def(AST_Call, function(compressor){
@@ -2838,7 +2830,6 @@ merge(Compressor.prototype, {
 
         def(AST_Node, return_this);
         def(AST_Constant, return_null);
-        def(AST_Super, return_null);
         def(AST_This, return_null);
         def(AST_Call, function(compressor, first_in_statement){
             if (!this.is_expr_pure(compressor)) {
@@ -2864,14 +2855,12 @@ 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 ]);
@@ -3795,7 +3784,7 @@ 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;
                             }
@@ -4295,8 +4284,7 @@ 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)
@@ -4348,6 +4336,7 @@ merge(Compressor.prototype, {
                 d.fixed = fixed = make_node(AST_Function, fixed, fixed);
             }
             if (compressor.option("unused")
+                && fixed
                 && d.references.length == 1
                 && (d.single_use || is_func_expr(fixed)
                     && !(d.scope.uses_arguments && d.orig[0] instanceof AST_SymbolFunarg)
@@ -4832,7 +4821,7 @@ merge(Compressor.prototype, {
             var has_special_symbol = false;
             self.walk(new TreeWalker(function(node) {
                 if (has_special_symbol) return true;
-                if (node instanceof AST_Super || node instanceof AST_This) {
+                if (node instanceof AST_This) {
                     has_special_symbol = true;
                     return true;
                 }

lib/output.js

@@ -1685,9 +1685,6 @@ function OutputStream(options) {
     DEFPRINT(AST_Symbol, function (self, output) {
         self._do_print(output);
     });
-    DEFPRINT(AST_SymbolDeclaration, function(self, output){
-        self._do_print(output);
-    });
     DEFPRINT(AST_Hole, noop);
     DEFPRINT(AST_This, function(self, output){
         output.print("this");

lib/parse.js

@@ -2565,7 +2565,7 @@ function parse($TEXT, options) {
                 unexpected(tmp);
             }
           case "name":
-            if (tmp.value == "yield" && !is_token(peek(), "punc", ":")
+            if (tmp.value == "yield" && !is_token(peek(), "punc", ":") && !is_token(peek(), "punc", "(")
                 && S.input.has_directive("use strict") && !is_in_generator()) {
                 token_error(tmp, "Unexpected yield identifier inside strict mode");
             }

package.json

@@ -4,7 +4,7 @@
   "homepage": "https://github.com/mishoo/UglifyJS2/tree/harmony",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.1.4",
+  "version": "3.1.5",
   "engines": {
     "node": ">=0.8.0"
   },

test/compress/arrow.js

@@ -631,3 +631,31 @@ issue_2271: {
     }
     expect_stdout: "PASS"
 }
+
+concise_method_with_super: {
+    options = {
+        arrows: true,
+    }
+    input: {
+        var o = {
+            f: "FAIL",
+            g() {
+                return super.f;
+            }
+        }
+        Object.setPrototypeOf(o, { f: "PASS" });
+        console.log(o.g());
+    }
+    expect: {
+        var o = {
+            f: "FAIL",
+            g() {
+                return super.f;
+            }
+        }
+        Object.setPrototypeOf(o, { f: "PASS" });
+        console.log(o.g());
+    }
+    expect_stdout: "PASS"
+    node_version: ">=4"
+}

test/compress/collapse_vars.js

@@ -2874,3 +2874,419 @@ prop_side_effects_2: {
         "2",
     ]
 }
+
+issue_2365: {
+    options = {
+        collapse_vars: true,
+        pure_getters: true,
+    }
+    input: {
+        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;
+            }
+        }.g());
+    }
+    expect: {
+        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;
+            }
+        }.g());
+    }
+    expect_stdout: [
+        "1",
+        "1",
+        "1",
+    ]
+}
+
+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,
+        pure_getters: true,
+        properties: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        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: {
+        function f0(o, a, h) {
+            return o.run(3 - a)[7] = h;
+        }
+    }
+}
+
+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"
+}

test/compress/reduce_vars.js

@@ -3051,3 +3051,63 @@ array_forof_2: {
     expect_stdout: "3"
     node_version: ">=0.12"
 }
+
+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"
+}

test/mocha/yield.js

@@ -102,4 +102,15 @@ describe("Yield", function() {
             assert.throws(test(tests[i]), fail, tests[i]);
         }
     });
+
+    it("Should allow yield to be used as class/object property name", function() {
+        var input = [
+            '"use strict";',
+            "({yield:42});",
+            "({yield(){}});",
+            "(class{yield(){}});",
+            "class C{yield(){}}",
+        ].join("");
+        assert.strictEqual(UglifyJS.minify(input, { compress: false }).code, input);
+    });
 });