v2.8.25

- fix `estree` conversion of getter/setter
- fix non-directive literal in `to_mozilla_ast()`
- revamp `test/mozilla-ast.js`
  - reuse `test/ufuzz.js` for code generation
  - use `acorn.parse()` for creating `estree`
- extend `test/ufuzz.js` for `acorn` workaround
  - catch variable redefinition
  - non-trivial literal as directive
  - adjust options for tolerance

Miscellaneous
- optional semi-colon when parsing directives

fixes #1914
closes #1915

README.md

@@ -11,9 +11,10 @@ There's also an
 Chrome and probably Safari).
 
 #### Note:
-- release versions of `uglify-js` only support ECMAScript 5 (ES5). If you wish to minify
-ES2015+ (ES6+) code then please use the [harmony](#harmony) development branch.
-- Node 7 has a known performance regression and runs `uglify-js` twice as slow.
+- `uglify-js` only supports ECMAScript 5 (ES5).
+- Support for `const` is [present but incomplete](#support-for-const), and may not be
+  transformed properly.
+- Those wishing to minify ES2015+ (ES6+) should use the `npm` package [**uglify-es**](https://github.com/mishoo/UglifyJS2/tree/harmony).
 
 Install
 -------
@@ -29,12 +30,6 @@ From NPM for programmatic use:
 
     npm install uglify-js
 
-From Git:
-
-    git clone git://github.com/mishoo/UglifyJS2.git
-    cd UglifyJS2
-    npm link .
-
 Usage
 -----
 
@@ -441,13 +436,19 @@ to set `true`; it's effectively a shortcut for `foo=true`).
   compressor from discarding function names.  Useful for code relying on
   `Function.prototype.name`. See also: the `keep_fnames` [mangle option](#mangle).
 
-- `passes` -- default `1`. Number of times to run compress. Use an
-  integer argument larger than 1 to further reduce code size in some cases.
-  Note: raising the number of passes will increase uglify compress time.
+- `passes` -- default `1`. Number of times to run compress with a maximum of 3.
+  In some cases more than one pass leads to further compressed code.  Keep in
+  mind more passes will take more time.
 
 - `keep_infinity` -- default `false`. Pass `true` to prevent `Infinity` from
   being compressed into `1/0`, which may cause performance issues on Chrome.
 
+- `side_effects` -- default `false`. Pass `true` to potentially drop functions
+marked as "pure".  A function call is marked as "pure" if a comment annotation
+`/*@__PURE__*/` or `/*#__PURE__*/` immediately precedes the call. For example:
+`/*@__PURE__*/foo()`;
+
+
 ### The `unsafe` option
 
 It enables some transformations that *might* break code logic in certain
@@ -983,19 +984,9 @@ The `source_map_options` (optional) can contain the following properties:
   [compressor]: http://lisperator.net/uglifyjs/compress
   [parser]: http://lisperator.net/uglifyjs/parser
 
-#### Harmony
+#### Support for `const`
 
-If you wish to use the experimental [harmony](https://github.com/mishoo/UglifyJS2/commits/harmony)
-branch to minify ES2015+ (ES6+) code please use the following in your `package.json` file:
-
-```
-"uglify-js": "git+https://github.com/mishoo/UglifyJS2.git#harmony"
-```
-
-or to directly install the experimental harmony version of uglify:
-
-```
-npm install --save-dev uglify-js@github:mishoo/UglifyJS2#harmony
-```
-
-See [#448](https://github.com/mishoo/UglifyJS2/issues/448) for additional details.
+`const` in `uglify-js@2.x` has function scope and as such behaves much like
+`var` - unlike `const` in ES2015 (ES6) which has block scope. It is recommended
+to avoid using `const` for this reason as it will have undefined behavior when
+run on an ES2015 compatible browser.

bin/uglifyjs

@@ -367,19 +367,19 @@ var index = 0;
                     if (ex instanceof UglifyJS.JS_Parse_Error) {
                         print_error("Parse error at " + file + ":" + ex.line + "," + ex.col);
                         var col = ex.col;
-                        var line = code.split(/\r?\n/)[ex.line - (col ? 1 : 2)];
+                        var lines = code.split(/\r?\n/);
+                        var line = lines[ex.line - 1];
+                        if (!line && !col) {
+                            line = lines[ex.line - 2];
+                            col = line.length;
+                        }
                         if (line) {
                             if (col > 40) {
                                 line = line.slice(col - 40);
                                 col = 40;
                             }
-                            if (col) {
-                                print_error(line.slice(0, 80));
-                                print_error(line.slice(0, col).replace(/\S/g, " ") + "^");
-                            } else {
-                                print_error(line.slice(-40));
-                                print_error(line.slice(-40).replace(/\S/g, " ") + "^");
-                            }
+                            print_error(line.slice(0, 80));
+                            print_error(line.slice(0, col).replace(/\S/g, " ") + "^");
                         }
                         print_error(ex.stack);
                         process.exit(1);

lib/ast.js

@@ -214,12 +214,13 @@ var AST_LabeledStatement = DEFNODE("LabeledStatement", "label", {
     clone: function(deep) {
         var node = this._clone(deep);
         if (deep) {
-            var refs = node.label.references;
-            var label = this.label;
+            var label = node.label;
+            var def = this.label;
             node.walk(new TreeWalker(function(node) {
                 if (node instanceof AST_LoopControl
-                    && node.label && node.label.thedef === label) {
-                    refs.push(node);
+                    && node.label && node.label.thedef === def) {
+                    node.label.thedef = label;
+                    label.references.push(node);
                 }
             }));
         }
@@ -797,8 +798,8 @@ var AST_Object = DEFNODE("Object", "properties", {
 var AST_ObjectProperty = DEFNODE("ObjectProperty", "key value", {
     $documentation: "Base class for literal object properties",
     $propdoc: {
-        key: "[string] the property name converted to a string for ObjectKeyVal.  For setters and getters this is an arbitrary AST_Node.",
-        value: "[AST_Node] property value.  For setters and getters this is an AST_Function."
+        key: "[string] the property name converted to a string for ObjectKeyVal.  For setters and getters this is an AST_SymbolAccessor.",
+        value: "[AST_Node] property value.  For setters and getters this is an AST_Accessor."
     },
     _walk: function(visitor) {
         return visitor._visit(this, function(){

lib/compress.js

@@ -271,6 +271,14 @@ merge(Compressor.prototype, {
                     if (d.fixed === undefined || !is_safe(d)
                         || is_modified(node, 0, node.fixed_value() instanceof AST_Lambda)) {
                         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;
+                        }
                     }
                 }
                 if (node instanceof AST_SymbolCatch) {
@@ -308,21 +316,55 @@ merge(Compressor.prototype, {
                     safe_ids = save_ids;
                     return true;
                 }
-                var iife;
-                if (node instanceof AST_Function
-                    && !node.name
-                    && (iife = tw.parent()) instanceof AST_Call
-                    && iife.expression === node) {
-                    // Virtually turn IIFE parameters into variable definitions:
-                    //   (function(a,b) {...})(c,d) => (function() {var a=c,b=d; ...})()
-                    // So existing transformation rules can work on them.
-                    node.argnames.forEach(function(arg, i) {
-                        var d = arg.definition();
-                        d.fixed = function() {
-                            return iife.args[i] || make_node(AST_Undefined, iife);
-                        };
-                        mark(d, true);
-                    });
+                if (node instanceof AST_Function) {
+                    push();
+                    var iife;
+                    if (!node.name
+                        && (iife = tw.parent()) instanceof AST_Call
+                        && iife.expression === node) {
+                        // Virtually turn IIFE parameters into variable definitions:
+                        //   (function(a,b) {...})(c,d) => (function() {var a=c,b=d; ...})()
+                        // So existing transformation rules can work on them.
+                        node.argnames.forEach(function(arg, i) {
+                            var d = arg.definition();
+                            if (!node.uses_arguments && d.fixed === undefined) {
+                                d.fixed = function() {
+                                    return iife.args[i] || make_node(AST_Undefined, iife);
+                                };
+                                mark(d, true);
+                            } else {
+                                d.fixed = false;
+                            }
+                        });
+                    }
+                    descend();
+                    pop();
+                    return true;
+                }
+                if (node instanceof AST_Accessor) {
+                    var save_ids = safe_ids;
+                    safe_ids = Object.create(null);
+                    descend();
+                    safe_ids = save_ids;
+                    return true;
+                }
+                if (node instanceof AST_Binary
+                    && (node.operator == "&&" || node.operator == "||")) {
+                    node.left.walk(tw);
+                    push();
+                    node.right.walk(tw);
+                    pop();
+                    return true;
+                }
+                if (node instanceof AST_Conditional) {
+                    node.condition.walk(tw);
+                    push();
+                    node.consequent.walk(tw);
+                    pop();
+                    push();
+                    node.alternative.walk(tw);
+                    pop();
+                    return true;
                 }
                 if (node instanceof AST_If || node instanceof AST_DWLoop) {
                     node.condition.walk(tw);
@@ -359,7 +401,19 @@ merge(Compressor.prototype, {
                     pop();
                     return true;
                 }
-                if (node instanceof AST_Catch || node instanceof AST_SwitchBranch) {
+                if (node instanceof AST_Try) {
+                    push();
+                    walk_body(node, tw);
+                    pop();
+                    if (node.bcatch) {
+                        push();
+                        node.bcatch.walk(tw);
+                        pop();
+                    }
+                    if (node.bfinally) node.bfinally.walk(tw);
+                    return true;
+                }
+                if (node instanceof AST_SwitchBranch) {
                     push();
                     descend();
                     pop();
@@ -393,7 +447,10 @@ merge(Compressor.prototype, {
         }
 
         function reset_def(def) {
-            if (toplevel || !def.global || def.orig[0] instanceof AST_SymbolConst) {
+            def.escaped = false;
+            if (def.scope.uses_eval) {
+                def.fixed = false;
+            } else if (toplevel || !def.global || def.orig[0] instanceof AST_SymbolConst) {
                 def.fixed = undefined;
             } else {
                 def.fixed = false;
@@ -419,6 +476,14 @@ merge(Compressor.prototype, {
         return fixed();
     });
 
+    function is_reference_const(ref) {
+        if (!(ref instanceof AST_SymbolRef)) return false;
+        var orig = ref.definition().orig;
+        for (var i = orig.length; --i >= 0;) {
+            if (orig[i] instanceof AST_SymbolConst) return true;
+        }
+    }
+
     function find_variable(compressor, name) {
         var scope, i = 0;
         while (scope = compressor.parent(i++)) {
@@ -1160,12 +1225,12 @@ merge(Compressor.prototype, {
                 && !node.expression.has_side_effects(compressor);
     }
 
-    // may_eq_null()
-    // returns true if this node may evaluate to null or undefined
+    // may_throw_on_access()
+    // returns true if this node may be null, undefined or contain `AST_Accessor`
     (function(def) {
-        AST_Node.DEFMETHOD("may_eq_null", function(compressor) {
+        AST_Node.DEFMETHOD("may_throw_on_access", function(compressor) {
             var pure_getters = compressor.option("pure_getters");
-            return !pure_getters || this._eq_null(pure_getters);
+            return !pure_getters || this._throw_on_access(pure_getters);
         });
 
         function is_strict(pure_getters) {
@@ -1177,7 +1242,12 @@ merge(Compressor.prototype, {
         def(AST_Undefined, return_true);
         def(AST_Constant, return_false);
         def(AST_Array, return_false);
-        def(AST_Object, return_false);
+        def(AST_Object, function(pure_getters) {
+            if (!is_strict(pure_getters)) return false;
+            for (var i = this.properties.length; --i >=0;)
+                if (this.properties[i].value instanceof AST_Accessor) return true;
+            return false;
+        });
         def(AST_Function, return_false);
         def(AST_UnaryPostfix, return_false);
         def(AST_UnaryPrefix, function() {
@@ -1186,33 +1256,33 @@ merge(Compressor.prototype, {
         def(AST_Binary, function(pure_getters) {
             switch (this.operator) {
               case "&&":
-                return this.left._eq_null(pure_getters);
+                return this.left._throw_on_access(pure_getters);
               case "||":
-                return this.left._eq_null(pure_getters)
-                    && this.right._eq_null(pure_getters);
+                return this.left._throw_on_access(pure_getters)
+                    && this.right._throw_on_access(pure_getters);
               default:
                 return false;
             }
         })
         def(AST_Assign, function(pure_getters) {
             return this.operator == "="
-                && this.right._eq_null(pure_getters);
+                && this.right._throw_on_access(pure_getters);
         })
         def(AST_Conditional, function(pure_getters) {
-            return this.consequent._eq_null(pure_getters)
-                || this.alternative._eq_null(pure_getters);
+            return this.consequent._throw_on_access(pure_getters)
+                || this.alternative._throw_on_access(pure_getters);
         })
         def(AST_Seq, function(pure_getters) {
-            return this.cdr._eq_null(pure_getters);
+            return this.cdr._throw_on_access(pure_getters);
         });
         def(AST_SymbolRef, function(pure_getters) {
             if (this.is_undefined) return true;
             if (!is_strict(pure_getters)) return false;
             var fixed = this.fixed_value();
-            return !fixed || fixed._eq_null(pure_getters);
+            return !fixed || fixed._throw_on_access(pure_getters);
         });
     })(function(node, func) {
-        node.DEFMETHOD("_eq_null", func);
+        node.DEFMETHOD("_throw_on_access", func);
     });
 
     /* -----[ boolean/negation helpers ]----- */
@@ -1549,23 +1619,20 @@ merge(Compressor.prototype, {
                 : ev(this.alternative, compressor);
         });
         def(AST_SymbolRef, function(compressor){
-            if (this._evaluating) throw def;
+            if (!compressor.option("reduce_vars") || this._evaluating) throw def;
             this._evaluating = true;
             try {
                 var fixed = this.fixed_value();
-                if (compressor.option("reduce_vars") && fixed) {
-                    if (compressor.option("unsafe")) {
-                        if (!HOP(fixed, "_evaluated")) {
-                            fixed._evaluated = ev(fixed, compressor);
-                        }
-                        return fixed._evaluated;
-                    }
-                    return ev(fixed, compressor);
-                }
+                if (!fixed) throw def;
+                var value = ev(fixed, compressor);
+                if (!HOP(fixed, "_eval")) fixed._eval = function() {
+                    return value;
+                };
+                if (value && typeof value == "object" && this.definition().escaped) throw def;
+                return value;
             } finally {
                 this._evaluating = false;
             }
-            throw def;
         });
         def(AST_PropAccess, function(compressor){
             if (compressor.option("unsafe")) {
@@ -1755,11 +1822,11 @@ merge(Compressor.prototype, {
             return any(this.elements, compressor);
         });
         def(AST_Dot, function(compressor){
-            return this.expression.may_eq_null(compressor)
+            return this.expression.may_throw_on_access(compressor)
                 || this.expression.has_side_effects(compressor);
         });
         def(AST_Sub, function(compressor){
-            return this.expression.may_eq_null(compressor)
+            return this.expression.may_throw_on_access(compressor)
                 || this.expression.has_side_effects(compressor)
                 || this.property.has_side_effects(compressor);
         });
@@ -1891,6 +1958,7 @@ merge(Compressor.prototype, {
                         && node instanceof AST_Assign
                         && node.operator == "="
                         && node.left instanceof AST_SymbolRef
+                        && !is_reference_const(node.left)
                         && scope === self) {
                         node.right.walk(tw);
                         return true;
@@ -1980,7 +2048,7 @@ merge(Compressor.prototype, {
                         }
                         return node;
                     }
-                    if (drop_vars && node instanceof AST_Definitions && !(tt.parent() instanceof AST_ForIn)) {
+                    if (drop_vars && node instanceof AST_Definitions && !(tt.parent() instanceof AST_ForIn && tt.parent().init === node)) {
                         var def = node.definitions.filter(function(def){
                             if (def.value) def.value = def.value.transform(tt);
                             var sym = def.name.definition();
@@ -2058,26 +2126,32 @@ merge(Compressor.prototype, {
                             return maintain_this_binding(tt.parent(), node, node.right.transform(tt));
                         }
                     }
+                    // certain combination of unused name + side effect leads to:
+                    //    https://github.com/mishoo/UglifyJS2/issues/44
+                    //    https://github.com/mishoo/UglifyJS2/issues/1830
+                    // that's an invalid AST.
+                    // We fix it at this stage by moving the `var` outside the `for`.
                     if (node instanceof AST_For) {
                         descend(node, this);
-
                         if (node.init instanceof AST_BlockStatement) {
-                            // certain combination of unused name + side effect leads to:
-                            //    https://github.com/mishoo/UglifyJS2/issues/44
-                            // that's an invalid AST.
-                            // We fix it at this stage by moving the `var` outside the `for`.
-
-                            var body = node.init.body.slice(0, -1);
-                            node.init = node.init.body.slice(-1)[0].body;
-                            body.push(node);
-
-                            return in_list ? MAP.splice(body) : make_node(AST_BlockStatement, node, {
-                                body: body
-                            });
+                            var block = node.init;
+                            node.init = block.body.pop();
+                            block.body.push(node);
+                            return in_list ? MAP.splice(block.body) : block;
                         } else if (is_empty(node.init)) {
                             node.init = null;
-                            return node;
                         }
+                        return node;
+                    }
+                    if (node instanceof AST_LabeledStatement && node.body instanceof AST_For) {
+                        descend(node, this);
+                        if (node.body instanceof AST_BlockStatement) {
+                            var block = node.body;
+                            node.body = block.body.pop();
+                            block.body.push(node);
+                            return in_list ? MAP.splice(block.body) : block;
+                        }
+                        return node;
                     }
                     if (node instanceof AST_Scope && node !== self)
                         return node;
@@ -2256,6 +2330,7 @@ merge(Compressor.prototype, {
             var args = trim(this.args, compressor, first_in_statement);
             return args && AST_Seq.from_array(args);
         });
+        def(AST_Accessor, return_null);
         def(AST_Function, return_null);
         def(AST_Binary, function(compressor, first_in_statement){
             var right = this.right.drop_side_effect_free(compressor);
@@ -2326,11 +2401,11 @@ merge(Compressor.prototype, {
             return values && AST_Seq.from_array(values);
         });
         def(AST_Dot, function(compressor, first_in_statement){
-            if (this.expression.may_eq_null(compressor)) return this;
+            if (this.expression.may_throw_on_access(compressor)) return this;
             return this.expression.drop_side_effect_free(compressor, first_in_statement);
         });
         def(AST_Sub, function(compressor, first_in_statement){
-            if (this.expression.may_eq_null(compressor)) return this;
+            if (this.expression.may_throw_on_access(compressor)) return this;
             var expression = this.expression.drop_side_effect_free(compressor, first_in_statement);
             if (!expression) return this.property.drop_side_effect_free(compressor, first_in_statement);
             var property = this.property.drop_side_effect_free(compressor);
@@ -2380,7 +2455,7 @@ merge(Compressor.prototype, {
             if (compressor.option("dead_code") && self instanceof AST_While) {
                 var a = [];
                 extract_declarations_from_unreachable_code(compressor, self.body, a);
-                return make_node(AST_BlockStatement, self, { body: a });
+                return make_node(AST_BlockStatement, self, { body: a }).optimize(compressor);
             }
             if (self instanceof AST_Do) {
                 var has_loop_control = false;
@@ -2389,7 +2464,8 @@ merge(Compressor.prototype, {
                     if (node instanceof AST_LoopControl && tw.loopcontrol_target(node) === self)
                         return has_loop_control = true;
                 });
-                self.walk(tw);
+                var parent = compressor.parent();
+                (parent instanceof AST_LabeledStatement ? parent : self).walk(tw);
                 if (!has_loop_control) return self.body;
             }
         }
@@ -2459,7 +2535,7 @@ merge(Compressor.prototype, {
                     }));
                 }
                 extract_declarations_from_unreachable_code(compressor, self.body, a);
-                return make_node(AST_BlockStatement, self, { body: a });
+                return make_node(AST_BlockStatement, self, { body: a }).optimize(compressor);
             }
             if (cond !== self.condition) {
                 cond = make_node_from_constant(cond, self.condition).transform(compressor);
@@ -2711,9 +2787,9 @@ merge(Compressor.prototype, {
             var body = [];
             if (self.bcatch) extract_declarations_from_unreachable_code(compressor, self.bcatch, body);
             if (self.bfinally) body = body.concat(self.bfinally.body);
-            return body.length > 0 ? make_node(AST_BlockStatement, self, {
+            return make_node(AST_BlockStatement, self, {
                 body: body
-            }).optimize(compressor) : make_node(AST_EmptyStatement, self);
+            }).optimize(compressor);
         }
         return self;
     });
@@ -3041,7 +3117,8 @@ merge(Compressor.prototype, {
             }
             if (left
                 && !(left instanceof AST_SymbolRef
-                    && left.definition().orig[0] instanceof AST_SymbolLambda)) {
+                    && (left.definition().orig[0] instanceof AST_SymbolLambda
+                        || is_reference_const(left)))) {
                 var parent, field;
                 var cdr = self.cdr;
                 while (true) {
@@ -3595,7 +3672,9 @@ merge(Compressor.prototype, {
                 return make_node(AST_Infinity, self).optimize(compressor);
             }
         }
-        if (compressor.option("evaluate") && compressor.option("reduce_vars")) {
+        if (compressor.option("evaluate")
+            && compressor.option("reduce_vars")
+            && is_lhs(self, compressor.parent()) !== self) {
             var d = self.definition();
             var fixed = self.fixed_value();
             if (fixed) {
@@ -3603,21 +3682,45 @@ merge(Compressor.prototype, {
                     var init = fixed.evaluate(compressor);
                     if (init !== fixed) {
                         init = make_node_from_constant(init, fixed);
-                        var value = best_of_expression(init.optimize(compressor), fixed).print_to_string().length;
+                        var value = 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 = Math.min(value, 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 = d.name.length;
-                        var freq = d.references.length;
-                        var overhead = d.global || !freq ? 0 : (name + 2 + value) / freq;
-                        d.should_replace = value <= name + overhead ? init : false;
+                        var overhead = 0;
+                        if (compressor.option("unused") && (!d.global || compressor.option("toplevel"))) {
+                            overhead = (name + 2 + value) / d.references.length;
+                        }
+                        d.should_replace = value <= name + overhead ? fn : false;
                     } else {
                         d.should_replace = false;
                     }
                 }
                 if (d.should_replace) {
-                    return best_of_expression(d.should_replace.optimize(compressor), fixed).clone(true);
+                    return d.should_replace();
                 }
             }
         }
         return self;
+
+        function has_symbol_ref(value) {
+            var found;
+            value.walk(new TreeWalker(function(node) {
+                if (node instanceof AST_SymbolRef) found = true;
+                if (found) return true;
+            }));
+            return found;
+        }
     });
 
     function is_atomic(lhs, self) {

lib/mozilla-ast.js

@@ -111,23 +111,19 @@
         },
         Property: function(M) {
             var key = M.key;
-            var name = key.type == "Identifier" ? key.name : key.value;
             var args = {
                 start    : my_start_token(key),
                 end      : my_end_token(M.value),
-                key      : name,
+                key      : key.type == "Identifier" ? key.name : key.value,
                 value    : from_moz(M.value)
             };
-            switch (M.kind) {
-              case "init":
-                return new AST_ObjectKeyVal(args);
-              case "set":
-                args.value.name = from_moz(key);
-                return new AST_ObjectSetter(args);
-              case "get":
-                args.value.name = from_moz(key);
-                return new AST_ObjectGetter(args);
-            }
+            if (M.kind == "init") return new AST_ObjectKeyVal(args);
+            args.key = new AST_SymbolAccessor({
+                name: args.key
+            });
+            args.value = new AST_Accessor(args.value);
+            if (M.kind == "get") return new AST_ObjectGetter(args);
+            if (M.kind == "set") return new AST_ObjectSetter(args);
         },
         ArrayExpression: function(M) {
             return new AST_Array({
@@ -256,10 +252,7 @@
     map("CallExpression", AST_Call, "callee>expression, arguments@args");
 
     def_to_moz(AST_Toplevel, function To_Moz_Program(M) {
-        return {
-            type: "Program",
-            body: M.body.map(to_moz)
-        };
+        return to_moz_scope("Program", M);
     });
 
     def_to_moz(AST_Defun, function To_Moz_FunctionDeclaration(M) {
@@ -267,7 +260,7 @@
             type: "FunctionDeclaration",
             id: to_moz(M.name),
             params: M.argnames.map(to_moz),
-            body: to_moz_block(M)
+            body: to_moz_scope("BlockStatement", M)
         }
     });
 
@@ -276,7 +269,7 @@
             type: "FunctionExpression",
             id: to_moz(M.name),
             params: M.argnames.map(to_moz),
-            body: to_moz_block(M)
+            body: to_moz_scope("BlockStatement", M)
         }
     });
 
@@ -382,11 +375,10 @@
     });
 
     def_to_moz(AST_ObjectProperty, function To_Moz_Property(M) {
-        var key = (
-            is_identifier(M.key)
-            ? {type: "Identifier", name: M.key}
-            : {type: "Literal", value: M.key}
-        );
+        var key = {
+            type: "Literal",
+            value: M.key instanceof AST_SymbolAccessor ? M.key.name : M.key
+        };
         var kind;
         if (M instanceof AST_ObjectKeyVal) {
             kind = "init";
@@ -547,8 +539,8 @@
         moz_to_me = new Function("U2", "my_start_token", "my_end_token", "from_moz", "return(" + moz_to_me + ")")(
             exports, my_start_token, my_end_token, from_moz
         );
-        me_to_moz = new Function("to_moz", "to_moz_block", "return(" + me_to_moz + ")")(
-            to_moz, to_moz_block
+        me_to_moz = new Function("to_moz", "to_moz_block", "to_moz_scope", "return(" + me_to_moz + ")")(
+            to_moz, to_moz_block, to_moz_scope
         );
         MOZ_TO_ME[moztype] = moz_to_me;
         def_to_moz(mytype, me_to_moz);
@@ -606,4 +598,14 @@
         };
     };
 
+    function to_moz_scope(type, node) {
+        var body = node.body.map(to_moz);
+        if (node.body[0] instanceof AST_SimpleStatement && node.body[0].body instanceof AST_String) {
+            body.unshift(to_moz(new AST_EmptyStatement(node.body[0])));
+        }
+        return {
+            type: type,
+            body: body
+        };
+    };
 })();

lib/output.js

@@ -190,11 +190,7 @@ function OutputStream(options) {
     var might_need_space = false;
     var might_need_semicolon = false;
     var might_add_newline = 0;
-    var last = null;
-
-    function last_char() {
-        return last.charAt(last.length - 1);
-    };
+    var last = "";
 
     var ensure_line_len = options.max_line_len ? function() {
         if (current_col > options.max_line_len) {
@@ -218,10 +214,11 @@ function OutputStream(options) {
     function print(str) {
         str = String(str);
         var ch = str.charAt(0);
+        var prev = last.charAt(last.length - 1);
         if (might_need_semicolon) {
             might_need_semicolon = false;
 
-            if ((!ch || ";}".indexOf(ch) < 0) && !/[;]$/.test(last)) {
+            if (prev == ":" && ch == "}" || (!ch || ";}".indexOf(ch) < 0) && prev != ";") {
                 if (options.semicolons || requireSemicolonChars(ch)) {
                     OUTPUT += ";";
                     current_col++;
@@ -258,7 +255,6 @@ function OutputStream(options) {
         }
 
         if (might_need_space) {
-            var prev = last_char();
             if ((is_identifier_char(prev)
                     && (is_identifier_char(ch) || ch == "\\"))
                 || (ch == "/" && ch == prev)

lib/parse.js

@@ -111,7 +111,7 @@ var WHITESPACE_CHARS = makePredicate(characters(" \u00a0\n\r\t\f\u000b\u200b\u20
 
 var NEWLINE_CHARS = makePredicate(characters("\n\r\u2028\u2029"));
 
-var PUNC_BEFORE_EXPRESSION = makePredicate(characters("[{(,.;:"));
+var PUNC_BEFORE_EXPRESSION = makePredicate(characters("[{(,;:"));
 
 var PUNC_CHARS = makePredicate(characters("[]{}(),;:"));
 
@@ -807,24 +807,20 @@ function parse($TEXT, options) {
         handle_regexp();
         switch (S.token.type) {
           case "string":
-            var dir = false;
-            if (S.in_directives === true) {
-                if ((is_token(peek(), "punc", ";") || peek().nlb) && S.token.raw.indexOf("\\") === -1) {
+            if (S.in_directives) {
+                tmp = peek();
+                if (S.token.raw.indexOf("\\") == -1
+                    && (tmp.nlb
+                        || is_token(tmp, "eof")
+                        || is_token(tmp, "punc", ";")
+                        || is_token(tmp, "punc", "}"))) {
                     S.input.add_directive(S.token.value);
                 } else {
                     S.in_directives = false;
                 }
             }
             var dir = S.in_directives, stat = simple_statement();
-            if (dir) {
-                return new AST_Directive({
-                    start : stat.body.start,
-                    end   : stat.body.end,
-                    quote : stat.body.quote,
-                    value : stat.body.value,
-                });
-            }
-            return stat;
+            return dir ? new AST_Directive(stat.body) : stat;
           case "num":
           case "regexp":
           case "operator":
@@ -1320,10 +1316,15 @@ function parse($TEXT, options) {
             var type = start.type;
             var name = as_property_name();
             if (type == "name" && !is("punc", ":")) {
+                var key = new AST_SymbolAccessor({
+                    start: S.token,
+                    name: as_property_name(),
+                    end: prev()
+                });
                 if (name == "get") {
                     a.push(new AST_ObjectGetter({
                         start : start,
-                        key   : as_atom_node(),
+                        key   : key,
                         value : create_accessor(),
                         end   : prev()
                     }));
@@ -1332,7 +1333,7 @@ function parse($TEXT, options) {
                 if (name == "set") {
                     a.push(new AST_ObjectSetter({
                         start : start,
-                        key   : as_atom_node(),
+                        key   : key,
                         value : create_accessor(),
                         end   : prev()
                     }));
@@ -1354,14 +1355,15 @@ function parse($TEXT, options) {
 
     function as_property_name() {
         var tmp = S.token;
-        next();
         switch (tmp.type) {
+          case "operator":
+            if (!KEYWORDS(tmp.value)) unexpected();
           case "num":
           case "string":
           case "name":
-          case "operator":
           case "keyword":
           case "atom":
+            next();
             return tmp.value;
           default:
             unexpected();
@@ -1370,16 +1372,9 @@ function parse($TEXT, options) {
 
     function as_name() {
         var tmp = S.token;
+        if (tmp.type != "name") unexpected();
         next();
-        switch (tmp.type) {
-          case "name":
-          case "operator":
-          case "keyword":
-          case "atom":
-            return tmp.value;
-          default:
-            unexpected();
-        }
+        return tmp.value;
     };
 
     function _make_symbol(type) {
@@ -1440,14 +1435,14 @@ function parse($TEXT, options) {
         if (is("operator") && UNARY_PREFIX(start.value)) {
             next();
             handle_regexp();
-            var ex = make_unary(AST_UnaryPrefix, start.value, maybe_unary(allow_calls));
+            var ex = make_unary(AST_UnaryPrefix, start, maybe_unary(allow_calls));
             ex.start = start;
             ex.end = prev();
             return ex;
         }
         var val = expr_atom(allow_calls);
         while (is("operator") && UNARY_POSTFIX(S.token.value) && !S.token.nlb) {
-            val = make_unary(AST_UnaryPostfix, S.token.value, val);
+            val = make_unary(AST_UnaryPostfix, S.token, val);
             val.start = start;
             val.end = S.token;
             next();
@@ -1455,9 +1450,10 @@ function parse($TEXT, options) {
         return val;
     };
 
-    function make_unary(ctor, op, expr) {
+    function make_unary(ctor, token, expr) {
+        var op = token.value;
         if ((op == "++" || op == "--") && !is_assignable(expr))
-            croak("Invalid use of " + op + " operator", null, ctor === AST_UnaryPrefix ? expr.start.col - 1 : null);
+            croak("Invalid use of " + op + " operator", token.line, token.col, token.pos);
         return new ctor({ operator: op, expression: expr });
     };
 

lib/scope.js

@@ -361,11 +361,6 @@ AST_Symbol.DEFMETHOD("unmangleable", function(options){
     return this.definition().unmangleable(options);
 });
 
-// property accessors are not mangleable
-AST_SymbolAccessor.DEFMETHOD("unmangleable", function(){
-    return true;
-});
-
 // labels are always mangleable
 AST_Label.DEFMETHOD("unmangleable", function(){
     return false;

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": "2.8.22",
+  "version": "2.8.25",
   "engines": {
     "node": ">=0.8.0"
   },
@@ -33,10 +33,7 @@
     "yargs": "~3.10.0"
   },
   "devDependencies": {
-    "acorn": "~0.6.0",
-    "escodegen": "~1.3.3",
-    "esfuzz": "~0.3.1",
-    "estraverse": "~1.5.1",
+    "acorn": "~5.0.3",
     "mocha": "~2.3.4"
   },
   "optionalDependencies": {

test/benchmark.js

@@ -11,8 +11,8 @@ if (!args.length) {
 }
 args.push("--stats");
 var urls = [
-    "https://code.jquery.com/jquery-3.1.1.js",
-    "https://code.angularjs.org/1.6.1/angular.js",
+    "https://code.jquery.com/jquery-3.2.1.js",
+    "https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.6.4/angular.js",
     "https://cdnjs.cloudflare.com/ajax/libs/mathjs/3.9.0/math.js",
     "https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.js",
     "https://unpkg.com/react@15.3.2/dist/react.js",

test/compress/collapse_vars.js

@@ -1592,3 +1592,49 @@ var_side_effects_3: {
     }
     expect_stdout: true
 }
+
+reassign_const_1: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function f() {
+            const a = 1;
+            a = 2;
+            return a;
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            const a = 1;
+            a = 2;
+            return a;
+        }
+        console.log(f());
+    }
+    expect_stdout: true
+}
+
+reassign_const_2: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        function f() {
+            const a = 1;
+            ++a;
+            return a;
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            const a = 1;
+            ++a;
+            return a;
+        }
+        console.log(f());
+    }
+    expect_stdout: true
+}

test/compress/dead-code.js

@@ -256,3 +256,19 @@ try_catch_finally: {
         "1",
     ]
 }
+
+accessor: {
+    options = {
+        side_effects: true,
+    }
+    input: {
+        ({
+            get a() {},
+            set a(v){
+                this.b = 2;
+            },
+            b: 1
+        });
+    }
+    expect: {}
+}

test/compress/drop-unused.js

@@ -1029,3 +1029,63 @@ delete_assign_2: {
     }
     expect_stdout: true
 }
+
+issue_1830_1: {
+    options = {
+        unused: true,
+    }
+    input: {
+        !function() {
+            L: for (var b = console.log(1); !1;) continue L;
+        }();
+    }
+    expect: {
+        !function() {
+            L: for (console.log(1); !1;) continue L;
+        }();
+    }
+    expect_stdout: "1"
+}
+
+issue_1830_2: {
+    options = {
+        unused: true,
+    }
+    input: {
+        !function() {
+            L: for (var a = 1, b = console.log(a); --a;) continue L;
+        }();
+    }
+    expect: {
+        !function() {
+            var a = 1;
+            L: for (console.log(a); --a;) continue L;
+        }();
+    }
+    expect_stdout: "1"
+}
+
+reassign_const: {
+    options = {
+        cascade: true,
+        sequences: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            const a = 1;
+            a = 2;
+            return a;
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            const a = 1;
+            return a = 2, a;
+        }
+        console.log(f());
+    }
+    expect_stdout: true
+}

test/compress/functions.js

@@ -93,3 +93,57 @@ issue_485_crashing_1530: {
         this, void 0;
     }
 }
+
+issue_1841_1: {
+    options = {
+        keep_fargs: false,
+        pure_getters: "strict",
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        var b = 10;
+        !function(arg) {
+            for (var key in "hi")
+                var n = arg.baz, n = [ b = 42 ];
+        }(--b);
+        console.log(b);
+    }
+    expect: {
+        var b = 10;
+        !function() {
+            for (var key in "hi") {
+                b = 42;
+            }
+        }(--b);
+        console.log(b);
+    }
+    expect_exact: "42"
+}
+
+issue_1841_2: {
+    options = {
+        keep_fargs: false,
+        pure_getters: false,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        var b = 10;
+        !function(arg) {
+            for (var key in "hi")
+                var n = arg.baz, n = [ b = 42 ];
+        }(--b);
+        console.log(b);
+    }
+    expect: {
+        var b = 10;
+        !function(arg) {
+            for (var key in "hi") {
+                arg.baz, b = 42;
+            }
+        }(--b);
+        console.log(b);
+    }
+    expect_exact: "42"
+}

test/compress/issue-1656.js

@@ -35,11 +35,11 @@ f7: {
         console.log(a, b);
     }
     expect_exact: [
-        "var a = 100, b = 10;",
+        "var b = 10;",
         "",
         "!function() {",
-        "    for (;b = a, !1; ) ;",
-        "}(), console.log(a, b);",
+        "    for (;b = 100, !1; ) ;",
+        "}(), console.log(100, b);",
     ]
     expect_stdout: true
 }

test/compress/issue-1833.js

@@ -0,0 +1,134 @@
+iife_for: {
+    options = {
+        negate_iife: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                L: for (;;) break L;
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        !function() {
+            !function() {
+                L: for (;;) break L;
+            }();
+        }();
+    }
+}
+
+iife_for_in: {
+    options = {
+        negate_iife: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                L: for (var a in x) break L;
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        !function() {
+            !function() {
+                L: for (var a in x) break L;
+            }();
+        }();
+    }
+}
+
+iife_do: {
+    options = {
+        negate_iife: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                L: do {
+                    break L;
+                } while (1);
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        !function() {
+            !function() {
+                L: do {
+                    break L;
+                } while (1);
+            }();
+        }();
+    }
+}
+
+iife_while: {
+    options = {
+        negate_iife: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            function g() {
+                L: while (1) break L;
+            }
+            g();
+        }
+        f();
+    }
+    expect: {
+        !function() {
+            !function() {
+                L: while (1) break L;
+            }();
+        }();
+    }
+}
+
+label_do: {
+    options = {
+        evaluate: true,
+        loops: true,
+    }
+    input: {
+        L: do {
+            continue L;
+        } while (0);
+    }
+    expect: {
+        L: do {
+            continue L;
+        } while (0);
+    }
+}
+
+label_while: {
+    options = {
+        evaluate: true,
+        dead_code: true,
+        loops: true,
+    }
+    input: {
+        function f() {
+            L: while (0) continue L;
+        }
+    }
+    expect_exact: "function f(){L:;}"
+}

test/compress/pure_getters.js

@@ -119,3 +119,62 @@ chained: {
         a.b.c;
     }
 }
+
+impure_getter_1: {
+    options = {
+        pure_getters: "strict",
+        side_effects: true,
+    }
+    input: {
+        ({
+            get a() {
+                console.log(1);
+            },
+            b: 1
+        }).a;
+        ({
+            get a() {
+                console.log(1);
+            },
+            b: 1
+        }).b;
+    }
+    expect: {
+        ({
+            get a() {
+                console.log(1);
+            },
+            b: 1
+        }).a;
+        ({
+            get a() {
+                console.log(1);
+            },
+            b: 1
+        }).b;
+    }
+    expect_stdout: "1"
+}
+
+impure_getter_2: {
+    options = {
+        pure_getters: true,
+        side_effects: true,
+    }
+    input: {
+        // will produce incorrect output because getter is not pure
+        ({
+            get a() {
+                console.log(1);
+            },
+            b: 1
+        }).a;
+        ({
+            get a() {
+                console.log(1);
+            },
+            b: 1
+        }).b;
+    }
+    expect: {}
+}

test/compress/reduce_vars.js

@@ -41,22 +41,22 @@ reduce_vars: {
         var A = 1;
         (function() {
             console.log(-3);
-            console.log(-4);
+            console.log(A - 5);
         })();
         (function f1() {
             var a = 2;
-            console.log(-3);
+            console.log(a - 5);
             eval("console.log(a);");
         })();
         (function f2(eval) {
             var a = 2;
-            console.log(-3);
+            console.log(a - 5);
             eval("console.log(a);");
         })(eval);
         (function() {
             return "yes";
         })();
-        console.log(2);
+        console.log(A + 1);
     }
     expect_stdout: true
 }
@@ -300,7 +300,7 @@ unsafe_evaluate_array: {
     }
 }
 
-unsafe_evaluate_equality: {
+unsafe_evaluate_equality_1: {
     options = {
         evaluate     : true,
         reduce_vars  : true,
@@ -308,47 +308,62 @@ unsafe_evaluate_equality: {
         unused       : true
     }
     input: {
-        function f0(){
+        function f0() {
             var a = {};
-            console.log(a === a);
+            return a === a;
         }
-
-        function f1(){
+        function f1() {
             var a = [];
-            console.log(a === a);
+            return a === a;
         }
+        console.log(f0(), f1());
+    }
+    expect: {
+        function f0() {
+            return true;
+        }
+        function f1() {
+            return true;
+        }
+        console.log(f0(), f1());
+    }
+    expect_stdout: true
+}
 
-        function f2(){
+unsafe_evaluate_equality_2: {
+    options = {
+        collapse_vars: true,
+        evaluate     : true,
+        passes       : 2,
+        reduce_vars  : true,
+        unsafe       : true,
+        unused       : true
+    }
+    input: {
+        function f2() {
             var a = {a:1, b:2};
             var b = a;
             var c = a;
-            console.log(b === c);
+            return b === c;
         }
-
-        function f3(){
+        function f3() {
             var a = [1, 2, 3];
             var b = a;
             var c = a;
-            console.log(b === c);
+            return b === c;
         }
+        console.log(f2(), f3());
     }
     expect: {
-        function f0(){
-            console.log(true);
+        function f2() {
+            return true;
         }
-
-        function f1(){
-            console.log(true);
-        }
-
-        function f2(){
-            console.log(true);
-        }
-
-        function f3(){
-            console.log(true);
+        function f3() {
+            return true;
         }
+        console.log(f2(), f3());
     }
+    expect_stdout: true
 }
 
 passes: {
@@ -1717,7 +1732,10 @@ redefine_arguments_3: {
         console.log(function() {
             var arguments;
             return typeof arguments;
-        }(), "number", "undefined");
+        }(), "number", function(x) {
+            var arguments = x;
+            return typeof arguments;
+        }());
     }
     expect_stdout: "object number undefined"
 }
@@ -1995,3 +2013,188 @@ catch_var: {
     }
     expect_stdout: "true"
 }
+
+issue_1814_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        const a = 42;
+        !function() {
+            var b = a;
+            !function(a) {
+                console.log(a++, b);
+            }(0);
+        }();
+    }
+    expect: {
+        const a = 42;
+        !function() {
+            !function(a) {
+                console.log(a++, 42);
+            }(0);
+        }();
+    }
+    expect_stdout: "0 42"
+}
+
+issue_1814_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        const a = "32";
+        !function() {
+            var b = a + 1;
+            !function(a) {
+                console.log(a++, b);
+            }(0);
+        }();
+    }
+    expect: {
+        const a = "32";
+        !function() {
+            !function(a) {
+                console.log(a++, "321");
+            }(0);
+        }();
+    }
+    expect_stdout: "0 '321'"
+}
+
+try_abort: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        !function() {
+            try {
+                var a = 1;
+                throw "";
+                var b = 2;
+            } catch (e) {
+            }
+            console.log(a, b);
+        }();
+    }
+    expect: {
+        !function() {
+            try {
+                var a = 1;
+                throw "";
+                var b = 2;
+            } catch (e) {
+            }
+            console.log(a, b);
+        }();
+    }
+    expect_stdout: "1 undefined"
+}
+
+issue_1865: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe: true,
+    }
+    input: {
+        function f(some) {
+            some.thing = false;
+        }
+        console.log(function() {
+            var some = { thing: true };
+            f(some);
+            return some.thing;
+        }());
+    }
+    expect: {
+        function f(some) {
+            some.thing = false;
+        }
+        console.log(function() {
+            var some = { thing: true };
+            f(some);
+            return some.thing;
+        }());
+    }
+    expect_stdout: true
+}
+
+issue_1922_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            arguments[0] = 2;
+            return a;
+        }(1));
+    }
+    expect: {
+        console.log(function(a) {
+            arguments[0] = 2;
+            return a;
+        }(1));
+    }
+    expect_stdout: "2"
+}
+
+issue_1922_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        console.log(function() {
+            var a;
+            eval("a = 1");
+            return a;
+        }(1));
+    }
+    expect: {
+        console.log(function() {
+            var a;
+            eval("a = 1");
+            return a;
+        }(1));
+    }
+    expect_stdout: "1"
+}
+
+accessor: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+    }
+    input: {
+        var a = 1;
+        console.log({
+            get a() {
+                a = 2;
+                return a;
+            },
+            b: 1
+        }.b, a);
+    }
+    expect: {
+        var a = 1;
+        console.log({
+            get a() {
+                a = 2;
+                return a;
+            },
+            b: 1
+        }.b, a);
+    }
+    expect_stdout: "1 1"
+}

test/compress/sequences.js

@@ -610,3 +610,27 @@ delete_seq_6: {
     }
     expect_stdout: true
 }
+
+reassign_const: {
+    options = {
+        cascade: true,
+        sequences: true,
+        side_effects: true,
+    }
+    input: {
+        function f() {
+            const a = 1;
+            a++;
+            return a;
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            const a = 1;
+            return a++, a;
+        }
+        console.log(f());
+    }
+    expect_stdout: true
+}

test/input/invalid/assign_4.js

@@ -0,0 +1 @@
+++null

test/input/invalid/dot_1.js

@@ -0,0 +1 @@
+a.=

test/input/invalid/dot_2.js

@@ -0,0 +1 @@
+%.a;

test/input/invalid/dot_3.js

@@ -0,0 +1 @@
+a./();

test/input/invalid/object.js

@@ -0,0 +1 @@
+console.log({%: 1});

test/mocha/accessorTokens-1492.js

@@ -16,7 +16,7 @@ describe("Accessor tokens", function() {
                 assert.equal(node.start.pos, 12);
                 assert.equal(node.end.endpos, 46);
 
-                assert(node.key instanceof UglifyJS.AST_SymbolRef);
+                assert(node.key instanceof UglifyJS.AST_SymbolAccessor);
                 assert.equal(node.key.start.pos, 16);
                 assert.equal(node.key.end.endpos, 22);
 

test/mocha/cli.js

@@ -298,12 +298,87 @@ describe("bin/uglifyjs", function () {
            assert.ok(err);
            assert.strictEqual(stdout, "");
            assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
-               "Parse error at test/input/invalid/assign_3.js:1,18",
+               "Parse error at test/input/invalid/assign_3.js:1,17",
                "console.log(3 || ++this);",
-               "                  ^",
+               "                 ^",
                "SyntaxError: Invalid use of ++ operator"
            ].join("\n"));
            done();
        });
     });
+    it("Should throw syntax error (++null)", function(done) {
+       var command = uglifyjscmd + ' test/input/invalid/assign_4.js';
+
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/assign_4.js:1,0",
+               "++null",
+               "^",
+               "SyntaxError: Invalid use of ++ operator"
+           ].join("\n"));
+           done();
+       });
+    });
+    it("Should throw syntax error (a.=)", function(done) {
+       var command = uglifyjscmd + ' test/input/invalid/dot_1.js';
+
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/dot_1.js:1,2",
+               "a.=",
+               "  ^",
+               "SyntaxError: Unexpected token: operator (=)"
+           ].join("\n"));
+           done();
+       });
+    });
+    it("Should throw syntax error (%.a)", function(done) {
+       var command = uglifyjscmd + ' test/input/invalid/dot_2.js';
+
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/dot_2.js:1,0",
+               "%.a;",
+               "^",
+               "SyntaxError: Unexpected token: operator (%)"
+           ].join("\n"));
+           done();
+       });
+    });
+    it("Should throw syntax error (a./();)", function(done) {
+       var command = uglifyjscmd + ' test/input/invalid/dot_3.js';
+
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/dot_3.js:1,2",
+               "a./();",
+               "  ^",
+               "SyntaxError: Unexpected token: operator (/)"
+           ].join("\n"));
+           done();
+       });
+    });
+    it("Should throw syntax error ({%: 1})", function(done) {
+       var command = uglifyjscmd + ' test/input/invalid/object.js';
+
+       exec(command, function (err, stdout, stderr) {
+           assert.ok(err);
+           assert.strictEqual(stdout, "");
+           assert.strictEqual(stderr.split(/\n/).slice(0, 4).join("\n"), [
+               "Parse error at test/input/invalid/object.js:1,13",
+               "console.log({%: 1});",
+               "             ^",
+               "SyntaxError: Unexpected token: operator (%)"
+           ].join("\n"));
+           done();
+       });
+    });
 });

test/mocha/directives.js

@@ -351,18 +351,28 @@ describe("Directives", function() {
         var tests = [
             [
                 '"use strict";"use strict";"use strict";"use foo";"use strict";;"use sloppy";doSomething("foo");',
-                '"use strict";"use foo";doSomething("foo");'
+                '"use strict";"use foo";doSomething("foo");',
+                'function f(){ "use strict" }',
+                'function f(){ "use asm" }',
+                'function f(){ "use nondirective" }',
+                'function f(){ ;"use strict" }',
+                'function f(){ "use \n"; }',
             ],
             [
                  // Nothing gets optimised in the compressor because "use asm" is the first statement
                 '"use asm";"use\\x20strict";1+1;',
-                '"use asm";;"use strict";1+1;' // Yet, the parser noticed that "use strict" wasn't a directive
+                '"use asm";;"use strict";1+1;', // Yet, the parser noticed that "use strict" wasn't a directive
+                'function f(){"use strict"}',
+                'function f(){"use asm"}',
+                'function f(){"use nondirective"}',
+                'function f(){}',
+                'function f(){}',
             ]
         ];
 
         for (var i = 0; i < tests.length; i++) {
             assert.strictEqual(
-                uglify.minify(tests[i][0], {fromString: true, compress: {collapse_vars: true, side_effects: true}}).code,
+                uglify.minify(tests[i][0], {fromString: true}).code,
                 tests[i][1],
                 tests[i][0]
             );

test/mocha/getter-setter.js

@@ -71,7 +71,7 @@ describe("Getters and setters", function() {
         var fail = function(data) {
             return function (e) {
                 return e instanceof UglifyJS.JS_Parse_Error &&
-                    e.message === "Invalid getter/setter name: " + data.operator;
+                    e.message === "Unexpected token: operator (" + data.operator + ")";
             };
         };
 

test/mozilla-ast.js

@@ -1,103 +1,87 @@
 // Testing UglifyJS <-> SpiderMonkey AST conversion
-// through generative testing.
+"use strict";
 
-var UglifyJS = require(".."),
-    escodegen = require("escodegen"),
-    esfuzz = require("esfuzz"),
-    estraverse = require("estraverse"),
-    prefix = "\r    ";
+var acorn = require("acorn");
+var ufuzz = require("./ufuzz");
+var UglifyJS = require("..");
 
-// Normalizes input AST for UglifyJS in order to get correct comparison.
-
-function normalizeInput(ast) {
-    return estraverse.replace(ast, {
-        enter: function(node, parent) {
-            switch (node.type) {
-                // Internally mark all the properties with semi-standard type "Property".
-                case "ObjectExpression":
-                    node.properties.forEach(function (property) {
-                        property.type = "Property";
-                    });
-                    break;
-
-                // Since UglifyJS doesn"t recognize different types of property keys,
-                // decision on SpiderMonkey node type is based on check whether key
-                // can be valid identifier or not - so we do in input AST.
-                case "Property":
-                    var key = node.key;
-                    if (key.type === "Literal" && typeof key.value === "string" && UglifyJS.is_identifier(key.value)) {
-                        node.key = {
-                            type: "Identifier",
-                            name: key.value
-                        };
-                    } else if (key.type === "Identifier" && !UglifyJS.is_identifier(key.name)) {
-                        node.key = {
-                            type: "Literal",
-                            value: key.name
-                        };
-                    }
-                    break;
-
-                // UglifyJS internally flattens all the expression sequences - either
-                // to one element (if sequence contains only one element) or flat list.
-                case "SequenceExpression":
-                    node.expressions = node.expressions.reduce(function flatten(list, expr) {
-                        return list.concat(expr.type === "SequenceExpression" ? expr.expressions.reduce(flatten, []) : [expr]);
-                    }, []);
-                    if (node.expressions.length === 1) {
-                        return node.expressions[0];
-                    }
-                    break;
-            }
-        }
-    });
-}
-
-module.exports = function(options) {
-    console.log("--- UglifyJS <-> Mozilla AST conversion");
-
-    for (var counter = 0; counter < options.iterations; counter++) {
-        process.stdout.write(prefix + counter + "/" + options.iterations);
-
-        var ast1 = normalizeInput(esfuzz.generate({
-            maxDepth: options.maxDepth
-        }));
-
-        var ast2 =
-            UglifyJS
-            .AST_Node
-            .from_mozilla_ast(ast1)
-            .to_mozilla_ast();
-
-        var astPair = [
-            {name: 'expected', value: ast1},
-            {name: 'actual', value: ast2}
-        ];
-
-        var jsPair = astPair.map(function(item) {
-            return {
-                name: item.name,
-                value: escodegen.generate(item.value)
+function try_beautify(code) {
+    var beautified;
+    try {
+        beautified = UglifyJS.minify(code, {
+            fromString: true,
+            compress: false,
+            mangle: false,
+            output: {
+                beautify: true,
+                bracketize: true
             }
         });
-
-        if (jsPair[0].value !== jsPair[1].value) {
-            var fs = require("fs");
-            var acorn = require("acorn");
-
-            fs.existsSync("tmp") || fs.mkdirSync("tmp");
-
-            jsPair.forEach(function (item) {
-                var fileName = "tmp/dump_" + item.name;
-                var ast = acorn.parse(item.value);
-                fs.writeFileSync(fileName + ".js", item.value);
-                fs.writeFileSync(fileName + ".json", JSON.stringify(ast, null, 2));
-            });
-
-            process.stdout.write("\n");
-            throw new Error("Got different outputs, check out tmp/dump_*.{js,json} for codes and ASTs.");
-        }
+    } catch (ex) {
+        beautified = { error: ex };
     }
+    if (beautified.error) {
+        console.log("// !!! beautify failed !!!");
+        console.log(beautified.error.stack);
+        console.log(code);
+    } else {
+        console.log("// (beautified)");
+        console.log(beautified.code);
+    }
+}
 
-    process.stdout.write(prefix + "Probability of error is less than " + (100 / options.iterations) + "%, stopping.\n");
-};
+function test(original, estree, description) {
+    var transformed;
+    try {
+        transformed = UglifyJS.minify(estree, {
+            fromString: true,
+            compress: false,
+            mangle: false,
+            spidermonkey: true
+        });
+    } catch (ex) {
+        transformed = { error: ex };
+    }
+    if (transformed.error || original !== transformed.code) {
+        console.log("//=============================================================");
+        console.log("// !!!!!! Failed... round", round);
+        console.log("// original code");
+        try_beautify(original);
+        console.log();
+        console.log();
+        console.log("//-------------------------------------------------------------");
+        console.log("//", description);
+        if (transformed.error) {
+            console.log(transformed.error.stack);
+        } else {
+            try_beautify(transformed.code);
+        }
+        console.log("!!!!!! Failed... round", round);
+        process.exit(1);
+    }
+}
+
+var num_iterations = ufuzz.num_iterations;
+for (var round = 1; round <= num_iterations; round++) {
+    process.stdout.write(round + " of " + num_iterations + "\r");
+    var code = ufuzz.createTopLevelCode();
+    var uglified = {
+        ast: UglifyJS.parse(code),
+        code: UglifyJS.minify(code, {
+            fromString: true,
+            compress: false,
+            mangle: false
+        }).code
+    };
+    test(uglified.code, uglified.ast.to_mozilla_ast(), "AST_Node.to_mozilla_ast()");
+    try {
+        test(uglified.code, acorn.parse(code), "acorn.parse()");
+    } catch (e) {
+        console.log("//=============================================================");
+        console.log("// acorn parser failed... round", round);
+        console.log(e);
+        console.log("// original code");
+        console.log(code);
+    }
+}
+console.log();

test/run-tests.js

@@ -23,12 +23,6 @@ mocha_tests();
 var run_sourcemaps_tests = require('./sourcemaps');
 run_sourcemaps_tests();
 
-var run_ast_conversion_tests = require("./mozilla-ast");
-
-run_ast_conversion_tests({
-    iterations: 1000
-});
-
 /* -----[ utils ]----- */
 
 function tmpl() {

test/sandbox.js

@@ -1,15 +1,37 @@
 var vm = require("vm");
 
+function safe_log(arg, level) {
+    if (arg) switch (typeof arg) {
+      case "function":
+        return arg.toString();
+      case "object":
+        if (/Error$/.test(arg.name)) return arg.toString();
+        arg.constructor.toString();
+        if (level--) for (var key in arg) {
+            if (!Object.getOwnPropertyDescriptor(arg, key).get) {
+                arg[key] = safe_log(arg[key], level);
+            }
+        }
+    }
+    return arg;
+}
+
 var FUNC_TOSTRING = [
     "Function.prototype.toString = Function.prototype.valueOf = function() {",
-    "    var ids = [];",
+    "    var id = 0;",
     "    return function() {",
-    "        var i = ids.indexOf(this);",
-    "        if (i < 0) {",
-    "            i = ids.length;",
-    "            ids.push(this);",
+    '        if (this === Array) return "[Function: Array]";',
+    '        if (this === Object) return "[Function: Object]";',
+    "        var i = this.name;",
+    '        if (typeof i != "number") {',
+    "            i = ++id;",
+    '            Object.defineProperty(this, "name", {',
+    "                get: function() {",
+    "                    return i;",
+    "                }",
+    "            });",
     "        }",
-    '        return "[Function: __func_" + i + "__]";',
+    '        return "[Function: " + i + "]";',
     "    }",
     "}();",
 ].join("\n");
@@ -21,15 +43,15 @@ exports.run_code = function(code) {
     };
     try {
         vm.runInNewContext([
-            "!function() {",
             FUNC_TOSTRING,
+            "!function() {",
             code,
             "}();",
         ].join("\n"), {
             console: {
                 log: function() {
                     return console.log.apply(console, [].map.call(arguments, function(arg) {
-                        return typeof arg == "function" || arg && /Error$/.test(arg.name) ? arg.toString() : arg;
+                        return safe_log(arg, 3);
                     }));
                 }
             }

test/ufuzz.js

@@ -2,7 +2,7 @@
 // derived from https://github.com/qfox/uglyfuzzer by Peter van der Zee
 "use strict";
 
-// check both cli and file modes of nodejs (!). See #1695 for details. and the various settings of uglify.
+// check both CLI and file modes of nodejs (!). See #1695 for details. and the various settings of uglify.
 // bin/uglifyjs s.js -c && bin/uglifyjs s.js -c passes=3 && bin/uglifyjs s.js -c passes=3 -m
 // cat s.js | node && node s.js && bin/uglifyjs s.js -c | node && bin/uglifyjs s.js -c passes=3 | node && bin/uglifyjs s.js -c passes=3 -m | node
 
@@ -20,49 +20,26 @@ var MAX_GENERATED_TOPLEVELS_PER_RUN = 1;
 var MAX_GENERATION_RECURSION_DEPTH = 12;
 var INTERVAL_COUNT = 100;
 
-var STMT_BLOCK = 0;
-var STMT_IF_ELSE = 1;
-var STMT_DO_WHILE = 2;
-var STMT_WHILE = 3;
-var STMT_FOR_LOOP = 4;
-var STMT_SEMI = 5;
-var STMT_EXPR = 6;
-var STMT_SWITCH = 7;
-var STMT_VAR = 8;
-var STMT_RETURN_ETC = 9;
-var STMT_FUNC_EXPR = 10;
-var STMT_TRY = 11;
-var STMT_C = 12;
-var STMTS_TO_USE = [
-    STMT_BLOCK,
-    STMT_IF_ELSE,
-    STMT_DO_WHILE,
-    STMT_WHILE,
-    STMT_FOR_LOOP,
-    STMT_SEMI,
-    STMT_EXPR,
-    STMT_SWITCH,
-    STMT_VAR,
-    STMT_RETURN_ETC,
-    STMT_FUNC_EXPR,
-    STMT_TRY,
-    STMT_C,
-];
-var STMT_ARG_TO_ID = {
-    block: STMT_BLOCK,
-    ifelse: STMT_IF_ELSE,
-    dowhile: STMT_DO_WHILE,
-    while: STMT_WHILE,
-    forloop: STMT_FOR_LOOP,
-    semi: STMT_SEMI,
-    expr: STMT_EXPR,
-    switch: STMT_SWITCH,
-    var: STMT_VAR,
-    stop: STMT_RETURN_ETC,
-    funcexpr: STMT_FUNC_EXPR,
-    try: STMT_TRY,
-    c: STMT_C,
-};
+var STMT_ARG_TO_ID = Object.create(null);
+var STMTS_TO_USE = [];
+function STMT_(name) {
+    return STMT_ARG_TO_ID[name] = STMTS_TO_USE.push(STMTS_TO_USE.length) - 1;
+}
+
+var STMT_BLOCK = STMT_("block");
+var STMT_IF_ELSE = STMT_("ifelse");
+var STMT_DO_WHILE = STMT_("dowhile");
+var STMT_WHILE = STMT_("while");
+var STMT_FOR_LOOP = STMT_("forloop");
+var STMT_FOR_IN = STMT_("forin");
+var STMT_SEMI = STMT_("semi");
+var STMT_EXPR = STMT_("expr");
+var STMT_SWITCH = STMT_("switch");
+var STMT_VAR = STMT_("var");
+var STMT_RETURN_ETC = STMT_("stop");
+var STMT_FUNC_EXPR = STMT_("funcexpr");
+var STMT_TRY = STMT_("try");
+var STMT_C = STMT_("c");
 
 var STMT_FIRST_LEVEL_OVERRIDE = -1;
 var STMT_SECOND_LEVEL_OVERRIDE = -1;
@@ -71,7 +48,9 @@ var STMT_COUNT_FROM_GLOBAL = true; // count statement depth from nearest functio
 var num_iterations = +process.argv[2] || 1/0;
 var verbose = false; // log every generated test
 var verbose_interval = false; // log every 100 generated tests
-var verbose_error = false;
+var use_strict = false;
+var catch_redef = require.main === module;
+var generate_directive = require.main === module;
 for (var i = 2; i < process.argv.length; ++i) {
     switch (process.argv[i]) {
       case '-v':
@@ -80,9 +59,6 @@ for (var i = 2; i < process.argv.length; ++i) {
       case '-V':
         verbose_interval = true;
         break;
-      case '-E':
-        verbose_error = true;
-        break;
       case '-t':
         MAX_GENERATED_TOPLEVELS_PER_RUN = +process.argv[++i];
         if (!MAX_GENERATED_TOPLEVELS_PER_RUN) throw new Error('Must generate at least one toplevel per run');
@@ -101,6 +77,15 @@ for (var i = 2; i < process.argv.length; ++i) {
         STMT_SECOND_LEVEL_OVERRIDE = STMT_ARG_TO_ID[name];
         if (!(STMT_SECOND_LEVEL_OVERRIDE >= 0)) throw new Error('Unknown statement name; use -? to get a list');
         break;
+      case '--no-catch-redef':
+        catch_redef = false;
+        break;
+      case '--no-directive':
+        generate_directive = false;
+        break;
+      case '--use-strict':
+        use_strict = true;
+        break;
       case '--stmt-depth-from-func':
         STMT_COUNT_FROM_GLOBAL = false;
         break;
@@ -122,11 +107,13 @@ for (var i = 2; i < process.argv.length; ++i) {
         console.log('<number>: generate this many cases (if used must be first arg)');
         console.log('-v: print every generated test case');
         console.log('-V: print every 100th generated test case');
-        console.log('-E: print generated test case with runtime error');
         console.log('-t <int>: generate this many toplevels per run (more take longer)');
         console.log('-r <int>: maximum recursion depth for generator (higher takes longer)');
         console.log('-s1 <statement name>: force the first level statement to be this one (see list below)');
         console.log('-s2 <statement name>: force the second level statement to be this one (see list below)');
+        console.log('--no-catch-redef: do not redefine catch variables');
+        console.log('--no-directive: do not generate directives');
+        console.log('--use-strict: generate "use strict"');
         console.log('--stmt-depth-from-func: reset statement depth counter at each function, counts from global otherwise');
         console.log('--only-stmt <statement names>: a comma delimited white list of statements that may be generated');
         console.log('--without-stmt <statement names>: a comma delimited black list of statements never to generate');
@@ -210,12 +197,33 @@ var ASSIGNMENTS = [
     '=',
     '=',
     '=',
+    '=',
+    '=',
+    '=',
+    '=',
+
+    '=',
+    '=',
+    '=',
+    '=',
+    '=',
+    '=',
+    '=',
+    '=',
+    '=',
+    '=',
 
-    '==',
-    '!=',
-    '===',
-    '!==',
     '+=',
+    '+=',
+    '+=',
+    '+=',
+    '+=',
+    '+=',
+    '+=',
+    '+=',
+    '+=',
+    '+=',
+
     '-=',
     '*=',
     '/=',
@@ -225,7 +233,8 @@ var ASSIGNMENTS = [
     '<<=',
     '>>=',
     '>>>=',
-    '%=' ];
+    '%=',
+];
 
 var UNARY_SAFE = [
     '+',
@@ -294,17 +303,33 @@ var TYPEOF_OUTCOMES = [
     'symbol',
     'crap' ];
 
+var unique_vars = [];
 var loops = 0;
 var funcs = 0;
+var labels = 10000;
 
 function rng(max) {
     var r = randomBytes(2).readUInt16LE(0) / 65536;
     return Math.floor(max * r);
 }
 
+function strictMode() {
+    return use_strict && rng(4) == 0 ? '"use strict";' : '';
+}
+
 function createTopLevelCode() {
-    if (rng(2) === 0) return createStatements(3, MAX_GENERATION_RECURSION_DEPTH, CANNOT_THROW, CANNOT_BREAK, CANNOT_CONTINUE, CANNOT_RETURN, 0);
-    return createFunctions(rng(MAX_GENERATED_TOPLEVELS_PER_RUN) + 1, MAX_GENERATION_RECURSION_DEPTH, IN_GLOBAL, ANY_TYPE, CANNOT_THROW, 0);
+    VAR_NAMES.length = INITIAL_NAMES_LEN; // prune any previous names still in the list
+    unique_vars.length = 0;
+    loops = 0;
+    funcs = 0;
+    return [
+        strictMode(),
+        'var a = 100, b = 10, c = 0;',
+        rng(2) == 0
+        ? createStatements(3, MAX_GENERATION_RECURSION_DEPTH, CANNOT_THROW, CANNOT_BREAK, CANNOT_CONTINUE, CANNOT_RETURN, 0)
+        : createFunctions(rng(MAX_GENERATED_TOPLEVELS_PER_RUN) + 1, MAX_GENERATION_RECURSION_DEPTH, IN_GLOBAL, ANY_TYPE, CANNOT_THROW, 0),
+        'console.log(null, a, b, c);' // preceding `null` makes for a cleaner output (empty string still shows up etc)
+    ].join('\n');
 }
 
 function createFunctions(n, recurmax, inGlobal, noDecl, canThrow, stmtDepth) {
@@ -332,21 +357,36 @@ function createArgs() {
     return args.join(', ');
 }
 
+function filterDirective(s) {
+    if (!generate_directive && !s[1] && /\("/.test(s[2])) s[2] = ';' + s[2];
+    return s;
+}
+
 function createFunction(recurmax, inGlobal, noDecl, canThrow, stmtDepth) {
     if (--recurmax < 0) { return ';'; }
     if (!STMT_COUNT_FROM_GLOBAL) stmtDepth = 0;
     var func = funcs++;
     var namesLenBefore = VAR_NAMES.length;
-    var name = (inGlobal || rng(5) > 0) ? 'f' + func : createVarName(MANDATORY, noDecl);
-    if (name === 'a' || name === 'b' || name === 'c') name = 'f' + func; // quick hack to prevent assignment to func names of being called
-    var s = '';
+    var name;
+    if (inGlobal || rng(5) > 0) name = 'f' + func;
+    else {
+        unique_vars.push('a', 'b', 'c');
+        name = createVarName(MANDATORY, noDecl);
+        unique_vars.length -= 3;
+    }
+    var s = [
+        'function ' + name + '(' + createParams() + '){',
+        strictMode()
+    ];
     if (rng(5) === 0) {
         // functions with functions. lower the recursion to prevent a mess.
-        s = 'function ' + name + '(' + createParams() + '){' + createFunctions(rng(5) + 1, Math.ceil(recurmax * 0.7), NOT_GLOBAL, ANY_TYPE, canThrow, stmtDepth) + '}\n';
+        s.push(createFunctions(rng(5) + 1, Math.ceil(recurmax * 0.7), NOT_GLOBAL, ANY_TYPE, canThrow, stmtDepth));
     } else {
         // functions with statements
-        s = 'function ' + name + '(' + createParams() + '){' + createStatements(3, recurmax, canThrow, CANNOT_THROW, CANNOT_CONTINUE, CAN_RETURN, stmtDepth) + '}\n';
+        s.push(createStatements(3, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth));
     }
+    s.push('}', '');
+    s = filterDirective(s).join('\n');
 
     VAR_NAMES.length = namesLenBefore;
 
@@ -354,7 +394,6 @@ function createFunction(recurmax, inGlobal, noDecl, canThrow, stmtDepth) {
     // avoid "function statements" (decl inside statements)
     else if (inGlobal || rng(10) > 0) s += 'var ' + createVarName(MANDATORY) + ' = ' + name + '(' + createArgs() + ');';
 
-
     return s;
 }
 
@@ -367,7 +406,41 @@ function createStatements(n, recurmax, canThrow, canBreak, canContinue, cannotRe
     return s;
 }
 
-function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) {
+function enableLoopControl(flag, defaultValue) {
+    return Array.isArray(flag) && flag.indexOf("") < 0 ? flag.concat("") : flag || defaultValue;
+}
+
+function createLabel(canBreak, canContinue) {
+    var label;
+    if (rng(10) < 3) {
+        label = ++labels;
+        if (Array.isArray(canBreak)) {
+            canBreak = canBreak.slice();
+        } else {
+            canBreak = canBreak ? [ "" ] : [];
+        }
+        canBreak.push(label);
+        if (Array.isArray(canContinue)) {
+            canContinue = canContinue.slice();
+        } else {
+            canContinue = canContinue ? [ "" ] : [];
+        }
+        canContinue.push(label);
+    }
+    return {
+        break: canBreak,
+        continue: canContinue,
+        target: label ? "L" + label + ": " : ""
+    };
+}
+
+function getLabel(label) {
+    if (!Array.isArray(label)) return "";
+    label = label[rng(label.length)];
+    return label && " L" + label;
+}
+
+function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth, target) {
     ++stmtDepth;
     var loop = ++loops;
     if (--recurmax < 0) {
@@ -375,24 +448,44 @@ function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn
     }
 
     // allow to forcefully generate certain structures at first or second recursion level
-    var target = 0;
-    if (stmtDepth === 1 && STMT_FIRST_LEVEL_OVERRIDE >= 0) target = STMT_FIRST_LEVEL_OVERRIDE;
-    else if (stmtDepth === 2 && STMT_SECOND_LEVEL_OVERRIDE >= 0) target = STMT_SECOND_LEVEL_OVERRIDE;
-    else target = STMTS_TO_USE[rng(STMTS_TO_USE.length)];
+    if (target === undefined) {
+        if (stmtDepth === 1 && STMT_FIRST_LEVEL_OVERRIDE >= 0) target = STMT_FIRST_LEVEL_OVERRIDE;
+        else if (stmtDepth === 2 && STMT_SECOND_LEVEL_OVERRIDE >= 0) target = STMT_SECOND_LEVEL_OVERRIDE;
+        else target = STMTS_TO_USE[rng(STMTS_TO_USE.length)];
+    }
 
     switch (target) {
       case STMT_BLOCK:
-        return '{' + createStatements(rng(5) + 1, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + '}';
+        var label = createLabel(canBreak);
+        return label.target + '{' + createStatements(rng(5) + 1, recurmax, canThrow, label.break, canContinue, cannotReturn, stmtDepth) + '}';
       case STMT_IF_ELSE:
         return 'if (' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ')' + createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + (rng(2) === 1 ? ' else ' + createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) : '');
       case STMT_DO_WHILE:
-        return '{var brake' + loop + ' = 5; do {' + createStatement(recurmax, canThrow, CAN_BREAK, CAN_CONTINUE, cannotReturn, stmtDepth) + '} while ((' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ') && --brake' + loop + ' > 0);}';
+        var label = createLabel(canBreak, canContinue);
+        canBreak = label.break || enableLoopControl(canBreak, CAN_BREAK);
+        canContinue = label.continue || enableLoopControl(canContinue, CAN_CONTINUE);
+        return '{var brake' + loop + ' = 5; ' + label.target + 'do {' + createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + '} while ((' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ') && --brake' + loop + ' > 0);}';
       case STMT_WHILE:
-        return '{var brake' + loop + ' = 5; while ((' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ') && --brake' + loop + ' > 0)' + createStatement(recurmax, canThrow, CAN_BREAK, CAN_CONTINUE, cannotReturn, stmtDepth) + '}';
+        var label = createLabel(canBreak, canContinue);
+        canBreak = label.break || enableLoopControl(canBreak, CAN_BREAK);
+        canContinue = label.continue || enableLoopControl(canContinue, CAN_CONTINUE);
+        return '{var brake' + loop + ' = 5; ' + label.target + 'while ((' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ') && --brake' + loop + ' > 0)' + createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + '}';
       case STMT_FOR_LOOP:
-        return 'for (var brake' + loop + ' = 5; (' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ') && brake' + loop + ' > 0; --brake' + loop + ')' + createStatement(recurmax, canThrow, CAN_BREAK, CAN_CONTINUE, cannotReturn, stmtDepth);
+        var label = createLabel(canBreak, canContinue);
+        canBreak = label.break || enableLoopControl(canBreak, CAN_BREAK);
+        canContinue = label.continue || enableLoopControl(canContinue, CAN_CONTINUE);
+        return label.target + 'for (var brake' + loop + ' = 5; (' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ') && brake' + loop + ' > 0; --brake' + loop + ')' + createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth);
+      case STMT_FOR_IN:
+        var label = createLabel(canBreak, canContinue);
+        canBreak = label.break || enableLoopControl(canBreak, CAN_BREAK);
+        canContinue = label.continue || enableLoopControl(canContinue, CAN_CONTINUE);
+        var optElementVar = '';
+        if (rng(5) > 1) {
+            optElementVar = 'c = 1 + c; var ' + createVarName(MANDATORY) + ' = expr' + loop + '[key' + loop + ']; ';
+        }
+        return '{var expr' + loop + ' = ' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + '; ' + label.target + ' for (var key' + loop + ' in expr' + loop + ') {' + optElementVar + createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + '}}';
       case STMT_SEMI:
-        return ';';
+        return use_strict && rng(20) === 0 ? '"use strict";' : ';';
       case STMT_EXPR:
         return createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ';';
       case STMT_SWITCH:
@@ -402,20 +495,22 @@ function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn
       case STMT_VAR:
         switch (rng(3)) {
           case 0:
+            unique_vars.push('c');
             var name = createVarName(MANDATORY);
-            if (name === 'c') name = 'a';
+            unique_vars.pop();
             return 'var ' + name + ';';
           case 1:
             // initializer can only have one expression
+            unique_vars.push('c');
             var name = createVarName(MANDATORY);
-            if (name === 'c') name = 'b';
+            unique_vars.pop();
             return 'var ' + name + ' = ' + createExpression(recurmax, NO_COMMA, stmtDepth, canThrow) + ';';
           default:
             // initializer can only have one expression
+            unique_vars.push('c');
             var n1 = createVarName(MANDATORY);
-            if (n1 === 'c') n1 = 'b';
             var n2 = createVarName(MANDATORY);
-            if (n2 === 'c') n2 = 'b';
+            unique_vars.pop();
             return 'var ' + n1 + ' = ' + createExpression(recurmax, NO_COMMA, stmtDepth, canThrow) + ', ' + n2 + ' = ' + createExpression(recurmax, NO_COMMA, stmtDepth, canThrow) + ';';
         }
       case STMT_RETURN_ETC:
@@ -424,8 +519,8 @@ function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn
           case 1:
           case 2:
           case 3:
-            if (canBreak && rng(5) === 0) return 'break;';
-            if (canContinue && rng(5) === 0) return 'continue;';
+            if (canBreak && rng(5) === 0) return 'break' + getLabel(canBreak) + ';';
+            if (canContinue && rng(5) === 0) return 'continue' + getLabel(canContinue) + ';';
             if (cannotReturn) return createExpression(recurmax, NO_COMMA, stmtDepth, canThrow) + ';';
             if (rng(3) == 0) return '/*3*/return;';
             return 'return ' + createExpression(recurmax, NO_COMMA, stmtDepth, canThrow) + ';';
@@ -456,8 +551,11 @@ function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn
             var nameLenBefore = VAR_NAMES.length;
             var catchName = createVarName(MANDATORY);
             var freshCatchName = VAR_NAMES.length !== nameLenBefore;
+            if (!catch_redef) unique_vars.push(catchName);
             s += ' catch (' + catchName + ') { ' + createStatements(3, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + ' }';
-            if (freshCatchName) VAR_NAMES.splice(nameLenBefore, 1); // remove catch name
+            // remove catch name
+            if (!catch_redef) unique_vars.pop();
+            if (freshCatchName) VAR_NAMES.splice(nameLenBefore, 1);
         }
         if (n !== 0) s += ' finally { ' + createStatements(3, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) + ' }';
         return s;
@@ -470,25 +568,27 @@ function createStatement(recurmax, canThrow, canBreak, canContinue, cannotReturn
 
 function createSwitchParts(recurmax, n, canThrow, canBreak, canContinue, cannotReturn, stmtDepth) {
     var hadDefault = false;
-    var s = '';
+    var s = [''];
+    canBreak = enableLoopControl(canBreak, CAN_BREAK);
     while (n-- > 0) {
         //hadDefault = n > 0; // disables weird `default` clause positioning (use when handling destabilizes)
         if (hadDefault || rng(5) > 0) {
-            s += '' +
-                'case ' + createExpression(recurmax, NO_COMMA, stmtDepth, canThrow) + ':\n' +
-                createStatements(rng(3) + 1, recurmax, canThrow, CAN_BREAK, canContinue, cannotReturn, stmtDepth) +
-                '\n' +
-                (rng(10) > 0 ? ' break;' : '/* fall-through */') +
-                '\n';
+            s.push(
+                'case ' + createExpression(recurmax, NO_COMMA, stmtDepth, canThrow) + ':',
+                createStatements(rng(3) + 1, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth),
+                rng(10) > 0 ? ' break;' : '/* fall-through */',
+                ''
+            );
         } else {
             hadDefault = true;
-            s += '' +
-                'default:\n' +
-                createStatements(rng(3) + 1, recurmax, canThrow, CAN_BREAK, canContinue, cannotReturn, stmtDepth) +
-                '\n';
+            s.push(
+                'default:',
+                createStatements(rng(3) + 1, recurmax, canThrow, canBreak, canContinue, cannotReturn, stmtDepth),
+                ''
+            );
         }
     }
-    return s;
+    return s.join('\n');
 }
 
 function createExpression(recurmax, noComma, stmtDepth, canThrow) {
@@ -530,37 +630,67 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
         return createExpression(recurmax, COMMA_OK, stmtDepth, canThrow);
       case p++:
         return createExpression(recurmax, noComma, stmtDepth, canThrow) + '?' + createExpression(recurmax, NO_COMMA, stmtDepth, canThrow) + ':' + createExpression(recurmax, noComma, stmtDepth, canThrow);
+      case p++:
       case p++:
         var nameLenBefore = VAR_NAMES.length;
+        unique_vars.push('c');
         var name = createVarName(MAYBE); // note: this name is only accessible from _within_ the function. and immutable at that.
-        if (name === 'c') name = 'a';
-        var s = '';
-        switch(rng(4)) {
+        unique_vars.pop();
+        var s = [];
+        switch (rng(5)) {
           case 0:
-            s = '(function ' + name + '(){' + createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth) + '})()';
+            s.push(
+                '(function ' + name + '(){',
+                strictMode(),
+                createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+                '})()'
+            );
             break;
           case 1:
-            s = '+function ' + name + '(){' + createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth) + '}()';
+            s.push(
+                '+function ' + name + '(){',
+                strictMode(),
+                createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+                '}()'
+            );
             break;
           case 2:
-            s = '!function ' + name + '(){' + createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth) + '}()';
+            s.push(
+                '!function ' + name + '(){',
+                strictMode(),
+                createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+                '}()'
+            );
+            break;
+          case 3:
+            s.push(
+                'void function ' + name + '(){',
+                strictMode(),
+                createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+                '}()'
+            );
             break;
           default:
-            s = 'void function ' + name + '(){' + createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth) + '}()';
+            var instantiate = rng(4) ? 'new ' : '';
+            s.push(
+                instantiate + 'function ' + name + '(){',
+                strictMode()
+            );
+            if (instantiate) for (var i = rng(4); --i >= 0;) {
+                if (rng(2)) s.push('this.' + getDotKey(true) + createAssignment() + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ';');
+                else  s.push('this[' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ']' + createAssignment() + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ';');
+            }
+            s.push(
+                createStatements(rng(5) + 1, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+                '}'
+            );
             break;
         }
         VAR_NAMES.length = nameLenBefore;
-        return s;
+        return filterDirective(s).join('\n');
       case p++:
       case p++:
         return createTypeofExpr(recurmax, stmtDepth, canThrow);
-      case p++:
-        return [
-            'new function() {',
-            rng(2) ? '' : createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ';',
-            'return ' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ';',
-            '}'
-        ].join('\n');
       case p++:
       case p++:
         // more like a parser test but perhaps comment nodes mess up the analysis?
@@ -600,19 +730,19 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
             ") || " + rng(10) + ").toString()[" +
             createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "] ";
       case p++:
-        return createArrayLiteral(recurmax, COMMA_OK, stmtDepth, canThrow);
+        return createArrayLiteral(recurmax, stmtDepth, canThrow);
       case p++:
-        return createObjectLiteral(recurmax, COMMA_OK, stmtDepth, canThrow);
+        return createObjectLiteral(recurmax, stmtDepth, canThrow);
       case p++:
-        return createArrayLiteral(recurmax, COMMA_OK, stmtDepth, canThrow) + '[' +
+        return createArrayLiteral(recurmax, stmtDepth, canThrow) + '[' +
             createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ']';
       case p++:
-        return createObjectLiteral(recurmax, COMMA_OK, stmtDepth, canThrow) + '[' +
+        return createObjectLiteral(recurmax, stmtDepth, canThrow) + '[' +
             createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ']';
       case p++:
-        return createArrayLiteral(recurmax, COMMA_OK, stmtDepth, canThrow) + '.' + getDotKey();
+        return createArrayLiteral(recurmax, stmtDepth, canThrow) + '.' + getDotKey();
       case p++:
-        return createObjectLiteral(recurmax, COMMA_OK, stmtDepth, canThrow) + '.' + getDotKey();
+        return createObjectLiteral(recurmax, stmtDepth, canThrow) + '.' + getDotKey();
       case p++:
         var name = getVarName();
         return name + ' && ' + name + '[' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + ']';
@@ -624,7 +754,7 @@ function _createExpression(recurmax, noComma, stmtDepth, canThrow) {
     return _createExpression(recurmax, noComma, stmtDepth, canThrow);
 }
 
-function createArrayLiteral(recurmax, noComma, stmtDepth, canThrow) {
+function createArrayLiteral(recurmax, stmtDepth, canThrow) {
     recurmax--;
     var arr = "[";
     for (var i = rng(6); --i >= 0;) {
@@ -657,18 +787,56 @@ var KEYS = [
     "3",
 ].concat(SAFE_KEYS);
 
-function getDotKey() {
-    return SAFE_KEYS[rng(SAFE_KEYS.length)];
+function getDotKey(assign) {
+    var key;
+    do {
+        key = SAFE_KEYS[rng(SAFE_KEYS.length)];
+    } while (assign && key == "length");
+    return key;
 }
 
-function createObjectLiteral(recurmax, noComma, stmtDepth, canThrow) {
-    recurmax--;
-    var obj = "({";
-    for (var i = rng(6); --i >= 0;) {
-        var key = KEYS[rng(KEYS.length)];
-        obj += key + ":(" + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + "), ";
+function createAccessor(recurmax, stmtDepth, canThrow) {
+    var namesLenBefore = VAR_NAMES.length;
+    var s;
+    var prop1 = getDotKey();
+    if (rng(2) == 0) {
+        s = [
+            'get ' + prop1 + '(){',
+            strictMode(),
+            createStatements(2, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+            createStatement(recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth, STMT_RETURN_ETC),
+            '},'
+        ];
+    } else {
+        var prop2;
+        do {
+            prop2 = getDotKey();
+        } while (prop1 == prop2);
+        s = [
+            'set ' + prop1 + '(' + createVarName(MANDATORY) + '){',
+            strictMode(),
+            createStatements(2, recurmax, canThrow, CANNOT_BREAK, CANNOT_CONTINUE, CAN_RETURN, stmtDepth),
+            'this.' + prop2 + createAssignment() + _createBinaryExpr(recurmax, COMMA_OK, stmtDepth, canThrow) + ';',
+            '},'
+        ];
     }
-    return obj + "})";
+    VAR_NAMES.length = namesLenBefore;
+    return filterDirective(s).join('\n');
+}
+
+function createObjectLiteral(recurmax, stmtDepth, canThrow) {
+    recurmax--;
+    var obj = ['({'];
+    for (var i = rng(6); --i >= 0;) {
+        if (rng(20) == 0) {
+            obj.push(createAccessor(recurmax, stmtDepth, canThrow));
+        } else {
+            var key = KEYS[rng(KEYS.length)];
+            obj.push(key + ':(' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow) + '),');
+        }
+    }
+    obj.push('})');
+    return obj.join('\n');
 }
 
 function createNestedBinaryExpr(recurmax, noComma, stmtDepth, canThrow) {
@@ -682,22 +850,23 @@ function _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) {
 function _createSimpleBinaryExpr(recurmax, noComma, stmtDepth, canThrow) {
     // intentionally generate more hardcore ops
     if (--recurmax < 0) return createValue();
+    var assignee, expr;
     switch (rng(30)) {
       case 0:
         return '(c = c + 1, ' + _createSimpleBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ')';
       case 1:
         return '(' + createUnarySafePrefix() + '(' + _createSimpleBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + '))';
       case 2:
-        var assignee = getVarName();
+        assignee = getVarName();
         return '(' + assignee + createAssignment() + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ')';
       case 3:
-        var assignee = getVarName();
-        var expr = '(' + assignee + '[' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow)
+        assignee = getVarName();
+        expr = '(' + assignee + '[' + createExpression(recurmax, COMMA_OK, stmtDepth, canThrow)
             + ']' + createAssignment() + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ')';
         return canThrow && rng(10) == 0 ? expr : '(' + assignee + ' && ' + expr + ')';
       case 4:
-        var assignee = getVarName();
-        var expr = '(' + assignee + '.' + getDotKey() + createAssignment()
+        assignee = getVarName();
+        expr = '(' + assignee + '.' + getDotKey(true) + createAssignment()
             + _createBinaryExpr(recurmax, noComma, stmtDepth, canThrow) + ')';
         return canThrow && rng(10) == 0 ? expr : '(' + assignee + ' && ' + expr + ')';
       default:
@@ -754,17 +923,24 @@ function getVarName() {
 
 function createVarName(maybe, dontStore) {
     if (!maybe || rng(2)) {
-        var name = VAR_NAMES[rng(VAR_NAMES.length)];
         var suffix = rng(3);
-        if (suffix) {
-            name += '_' + suffix;
-            if (!dontStore) VAR_NAMES.push(name);
-        }
+        var name;
+        do {
+            name = VAR_NAMES[rng(VAR_NAMES.length)];
+            if (suffix) name += '_' + suffix;
+        } while (unique_vars.indexOf(name) >= 0);
+        if (suffix && !dontStore) VAR_NAMES.push(name);
         return name;
     }
     return '';
 }
 
+if (require.main !== module) {
+    exports.createTopLevelCode = createTopLevelCode;
+    exports.num_iterations = num_iterations;
+    return;
+}
+
 function try_beautify(code, result) {
     try {
         var beautified = UglifyJS.minify(code, {
@@ -802,8 +978,8 @@ var default_options = {
     mangle: {
         "cache": null,
         "eval": false,
+        "ie8": false,
         "keep_fnames": false,
-        "screw_ie8": true,
         "toplevel": false,
     },
     output: infer_options(UglifyJS.OutputStream),
@@ -858,17 +1034,27 @@ function log(options) {
     } else {
         console.log("// !!! uglify failed !!!");
         console.log(uglify_code.stack);
+        if (typeof original_result != "string") {
+            console.log();
+            console.log();
+            console.log("original stacktrace:");
+            console.log(original_result.stack);
+        }
     }
     console.log("minify(options):");
     options = JSON.parse(options);
     console.log(options);
     console.log();
-    if (!ok) {
+    if (!ok && typeof uglify_code == "string") {
         Object.keys(default_options).forEach(log_suspects.bind(null, options));
         console.log("!!!!!! Failed... round", round);
     }
 }
 
+var fallback_options = [ JSON.stringify({
+    compress: false,
+    mangle: false
+}) ];
 var minify_options = require("./ufuzz.json").map(function(options) {
     options.fromString = true;
     return JSON.stringify(options);
@@ -878,17 +1064,9 @@ var uglify_code, uglify_result, ok;
 for (var round = 1; round <= num_iterations; round++) {
     process.stdout.write(round + " of " + num_iterations + "\r");
 
-    VAR_NAMES.length = INITIAL_NAMES_LEN; // prune any previous names still in the list
-    loops = 0;
-    funcs = 0;
-
-    original_code = [
-        "var a = 100, b = 10, c = 0;",
-        createTopLevelCode(),
-        "console.log(null, a, b, c);" // preceding `null` makes for a cleaner output (empty string still shows up etc)
-    ].join("\n");
-
-    minify_options.forEach(function(options) {
+    original_code = createTopLevelCode();
+    original_result = sandbox.run_code(original_code);
+    (typeof original_result != "string" ? fallback_options : minify_options).forEach(function(options) {
         try {
             uglify_code = UglifyJS.minify(original_code, JSON.parse(options)).code;
         } catch (e) {
@@ -897,12 +1075,13 @@ for (var round = 1; round <= num_iterations; round++) {
 
         ok = typeof uglify_code == "string";
         if (ok) {
-            original_result = sandbox.run_code(original_code);
             uglify_result = sandbox.run_code(uglify_code);
             ok = sandbox.same_stdout(original_result, uglify_result);
+        } else if (typeof original_result != "string") {
+            ok = uglify_code.name == original_result.name;
         }
         if (verbose || (verbose_interval && !(round % INTERVAL_COUNT)) || !ok) log(options);
-        else if (verbose_error && typeof original_result != "string") {
+        else if (typeof original_result != "string") {
             console.log("//=============================================================");
             console.log("// original code");
             try_beautify(original_code, original_result);