v2.1.7

AST_Accessor will represent the function for a setter or getter.  Since they
are not mangleable, and they should not introduce a name in scope, we have a
new node for their name (AST_SymbolAccessor) which doesn't inherit from
AST_SymbolDeclaration.

fix #37

bin/uglifyjs2

@@ -252,7 +252,7 @@ if (SCOPE_IS_NEEDED) {
     time_it("scope", function(){
         TOPLEVEL.figure_out_scope();
         if (MANGLE) {
-            TOPLEVEL.compute_char_frequency();
+            TOPLEVEL.compute_char_frequency(MANGLE);
         }
     });
 }

lib/ast.js

@@ -345,6 +345,10 @@ var AST_Lambda = DEFNODE("Lambda", "name argnames uses_arguments", {
     }
 }, AST_Scope);
 
+var AST_Accessor = DEFNODE("Accessor", null, {
+    $documentation: "A setter/getter function"
+}, AST_Lambda);
+
 var AST_Function = DEFNODE("Function", null, {
     $documentation: "A function expression"
 }, AST_Lambda);
@@ -581,6 +585,18 @@ var AST_Seq = DEFNODE("Seq", "car cdr", {
         }
         return list;
     },
+    to_array: function() {
+        var p = this, a = [];
+        while (p) {
+            a.push(p.car);
+            if (p.cdr && !(p.cdr instanceof AST_Seq)) {
+                a.push(p.cdr);
+                break;
+            }
+            p = p.cdr;
+        }
+        return a;
+    },
     add: function(node) {
         var p = this;
         while (p) {
@@ -746,6 +762,10 @@ var AST_Symbol = DEFNODE("Symbol", "scope name thedef", {
     $documentation: "Base class for all symbols",
 });
 
+var AST_SymbolAccessor = DEFNODE("SymbolAccessor", null, {
+    $documentation: "The name of a property accessor (setter/getter function)"
+}, AST_Symbol);
+
 var AST_SymbolDeclaration = DEFNODE("SymbolDeclaration", "init", {
     $documentation: "A declaration symbol (symbol in var/const, function name or argument, symbol in catch)",
     $propdoc: {

lib/compress.js

@@ -53,6 +53,7 @@ function Compressor(options, false_by_default) {
         dead_code     : !false_by_default,
         drop_debugger : !false_by_default,
         unsafe        : !false_by_default,
+        unsafe_comps  : false,
         conditionals  : !false_by_default,
         comparisons   : !false_by_default,
         evaluate      : !false_by_default,
@@ -427,12 +428,23 @@ merge(Compressor.prototype, {
             var ret = [], prev = null;
             statements.forEach(function(stat){
                 if (prev) {
-                    if (stat instanceof AST_For && stat.init && !(stat.init instanceof AST_Definitions)) {
-                        stat.init = cons_seq(stat.init);
-                    }
-                    else if (stat instanceof AST_For && !stat.init) {
-                        stat.init = prev.body;
-                        ret.pop();
+                    if (stat instanceof AST_For) {
+                        var opera = {};
+                        try {
+                            prev.body.walk(new TreeWalker(function(node){
+                                if (node instanceof AST_Binary && node.operator == "in")
+                                    throw opera;
+                            }));
+                            if (stat.init && !(stat.init instanceof AST_Definitions)) {
+                                stat.init = cons_seq(stat.init);
+                            }
+                            else if (!stat.init) {
+                                stat.init = prev.body;
+                                ret.pop();
+                            }
+                        } catch(ex) {
+                            if (ex !== opera) throw ex;
+                        }
                     }
                     else if (stat instanceof AST_If) {
                         stat.condition = cons_seq(stat.condition);
@@ -692,7 +704,7 @@ merge(Compressor.prototype, {
         });
         def(AST_Binary, function(compressor){
             var self = this.clone(), op = this.operator;
-            if (compressor.option("comparisons") && compressor.option("unsafe")) {
+            if (compressor.option("unsafe_comps")) {
                 switch (op) {
                   case "<=" : self.operator = ">"  ; return self;
                   case "<"  : self.operator = ">=" ; return self;
@@ -1014,7 +1026,7 @@ merge(Compressor.prototype, {
         if (hoist_funs || hoist_vars) {
             var dirs = [];
             var hoisted = [];
-            var vars = {}, vars_found = 0, var_decl = 0;
+            var vars = new Dictionary(), vars_found = 0, var_decl = 0;
             // let's count var_decl first, we seem to waste a lot of
             // space if we hoist `var` when there's only one.
             self.walk(new TreeWalker(function(node){
@@ -1039,7 +1051,7 @@ merge(Compressor.prototype, {
                         }
                         if (node instanceof AST_Var && hoist_vars) {
                             node.definitions.forEach(function(def){
-                                vars[def.name.name] = def;
+                                vars.set(def.name.name, def);
                                 ++vars_found;
                             });
                             var seq = node.to_assignments();
@@ -1063,8 +1075,8 @@ merge(Compressor.prototype, {
             );
             self = self.transform(tt);
             if (vars_found > 0) hoisted.unshift(make_node(AST_Var, self, {
-                definitions: Object.keys(vars).map(function(name){
-                    var def = vars[name].clone();
+                definitions: vars.map(function(def){
+                    def = def.clone();
                     def.value = null;
                     return def;
                 })
@@ -1106,6 +1118,15 @@ merge(Compressor.prototype, {
         return self;
     });
 
+    OPT(AST_While, function(self, compressor) {
+        if (!compressor.option("loops")) return self;
+        self = AST_DWLoop.prototype.optimize.call(self, compressor);
+        if (self instanceof AST_While) {
+            self = make_node(AST_For, self, self);
+        }
+        return self;
+    });
+
     OPT(AST_For, function(self, compressor){
         var cond = self.condition;
         if (cond) {
@@ -1220,8 +1241,8 @@ merge(Compressor.prototype, {
             return make_node(self.body.CTOR, self, {
                 value: make_node(AST_Conditional, self, {
                     condition   : self.condition,
-                    consequent  : self.body.value,
-                    alternative : self.alternative.value || make_node(AST_Undefined, self).optimize(compressor)
+                    consequent  : self.body.value || make_node(AST_Undefined, self.body).optimize(compressor),
+                    alternative : self.alternative.value || make_node(AST_Undefined, self.alternative).optimize(compressor)
                 })
             }).transform(compressor);
         }
@@ -1380,6 +1401,10 @@ merge(Compressor.prototype, {
     });
 
     OPT(AST_Seq, function(self, compressor){
+        if (!compressor.option("side_effects"))
+            return self;
+        if (!self.car.has_side_effects())
+            return self.cdr;
         if (compressor.option("cascade")) {
             if (self.car instanceof AST_Assign
                 && !self.car.left.has_side_effects()
@@ -1395,7 +1420,26 @@ merge(Compressor.prototype, {
         return self;
     });
 
+    AST_Unary.DEFMETHOD("lift_sequences", function(compressor){
+        if (compressor.option("sequences")) {
+            if (this.expression instanceof AST_Seq) {
+                var seq = this.expression;
+                var x = seq.to_array();
+                this.expression = x.pop();
+                x.push(this);
+                seq = AST_Seq.from_array(x).transform(compressor);
+                return seq;
+            }
+        }
+        return this;
+    });
+
+    OPT(AST_UnaryPostfix, function(self, compressor){
+        return self.lift_sequences(compressor);
+    });
+
     OPT(AST_UnaryPrefix, function(self, compressor){
+        self = self.lift_sequences(compressor);
         var e = self.expression;
         if (compressor.option("booleans") && compressor.in_boolean_context()) {
             switch (self.operator) {
@@ -1411,14 +1455,53 @@ merge(Compressor.prototype, {
                 compressor.warn("Boolean expression always true [{file}:{line},{col}]", self.start);
                 return make_node(AST_True, self);
             }
-        }
-        if (e instanceof AST_Binary) {
-            self = best_of(self, e.negate(compressor));
+            if (e instanceof AST_Binary && self.operator == "!") {
+                self = best_of(self, e.negate(compressor));
+            }
         }
         return self.evaluate(compressor)[0];
     });
 
+    AST_Binary.DEFMETHOD("lift_sequences", function(compressor){
+        if (compressor.option("sequences")) {
+            if (this.left instanceof AST_Seq) {
+                var seq = this.left;
+                var x = seq.to_array();
+                this.left = x.pop();
+                x.push(this);
+                seq = AST_Seq.from_array(x).transform(compressor);
+                return seq;
+            }
+            if (this.right instanceof AST_Seq
+                && !(this.operator == "||" || this.operator == "&&")
+                && !this.left.has_side_effects()) {
+                var seq = this.right;
+                var x = seq.to_array();
+                this.right = x.pop();
+                x.push(this);
+                seq = AST_Seq.from_array(x).transform(compressor);
+                return seq;
+            }
+        }
+        return this;
+    });
+
+    var commutativeOperators = makePredicate("== === != !== * & | ^");
+
     OPT(AST_Binary, function(self, compressor){
+        function reverse(op) {
+            if (op) self.operator = op;
+            var tmp = self.left;
+            self.left = self.right;
+            self.right = tmp;
+        };
+        if (commutativeOperators(self.operator)) {
+            if (self.right instanceof AST_Constant
+                && !(self.left instanceof AST_Constant)) {
+                reverse();
+            }
+        }
+        self = self.lift_sequences(compressor);
         if (compressor.option("comparisons")) switch (self.operator) {
           case "===":
           case "!==":
@@ -1429,21 +1512,10 @@ merge(Compressor.prototype, {
             // XXX: intentionally falling down to the next case
           case "==":
           case "!=":
-            if (self.left instanceof AST_UnaryPrefix
-                && self.left.operator == "typeof"
-                && self.right instanceof AST_String
-                && self.right.value == "undefined") {
-                if (!(self.left.expression instanceof AST_SymbolRef)
-                    || !self.left.expression.undeclared()) {
-                    self.left = self.left.expression;
-                    self.right = make_node(AST_Undefined, self.right).optimize(compressor);
-                    if (self.operator.length == 2) self.operator += "=";
-                }
-            }
-            else if (self.left instanceof AST_String
-                     && self.left.value == "undefined"
-                     && self.right instanceof AST_UnaryPrefix
-                     && self.right.operator == "typeof") {
+            if (self.left instanceof AST_String
+                && self.left.value == "undefined"
+                && self.right instanceof AST_UnaryPrefix
+                && self.right.operator == "typeof") {
                 if (!(self.right.expression instanceof AST_SymbolRef)
                     || !self.right.expression.undeclared()) {
                     self.left = self.right.expression;
@@ -1506,12 +1578,6 @@ merge(Compressor.prototype, {
                 });
                 self = best_of(self, negated);
             }
-            var reverse = function(op) {
-                self.operator = op;
-                var tmp = self.left;
-                self.left = self.right;
-                self.right = tmp;
-            };
             switch (self.operator) {
               case "<": reverse(">"); break;
               case "<=": reverse(">="); break;
@@ -1557,6 +1623,7 @@ merge(Compressor.prototype, {
 
     var ASSIGN_OPS = [ '+', '-', '/', '*', '%', '>>', '<<', '>>>', '|', '^', '&' ];
     OPT(AST_Assign, function(self, compressor){
+        self = self.lift_sequences(compressor);
         if (self.operator == "="
             && self.left instanceof AST_SymbolRef
             && self.right instanceof AST_Binary

lib/output.js

@@ -137,7 +137,7 @@ function OutputStream(options) {
         str = String(str);
         var ch = str.charAt(0);
         if (might_need_semicolon) {
-            if (";}".indexOf(ch) < 0 && !/[;]$/.test(last)) {
+            if ((!ch || ";}".indexOf(ch) < 0) && !/[;]$/.test(last)) {
                 if (options.semicolons || requireSemicolonChars(ch)) {
                     OUTPUT += ";";
                     current_col++;
@@ -410,11 +410,16 @@ function OutputStream(options) {
         return first_in_statement(output);
     });
 
+    PARENS(AST_Unary, function(output){
+        var p = output.parent();
+        return p instanceof AST_PropAccess;
+    });
+
     PARENS(AST_Seq, function(output){
         var p = output.parent();
         return p instanceof AST_Call             // (foo, bar)() or foo(1, (2, 3), 4)
             || p instanceof AST_Unary            // !(foo, bar, baz)
-            || p instanceof AST_Binary           // 1 + (2, 3) + 4 ==> 7
+            || p instanceof AST_Binary           // 1 + (2, 3) + 4 ==> 8
             || p instanceof AST_VarDef           // var a = (1, 2), b = a + a; ==> b == 4
             || p instanceof AST_Dot              // (1, {foo:2}).foo ==> 2
             || p instanceof AST_Array            // [ 1, (2, 3), 4 ] ==> [ 1, 3, 4 ]
@@ -463,10 +468,21 @@ function OutputStream(options) {
         }
     });
 
+    PARENS(AST_PropAccess, function(output){
+        var p = output.parent();
+        return p instanceof AST_New && p.expression === this;
+    });
+
+    PARENS(AST_Call, function(output){
+        var p = output.parent();
+        return p instanceof AST_New && p.expression === this;
+    });
+
     PARENS(AST_New, function(output){
         var p = output.parent();
-        // (new Date).getTime();
-        if (p instanceof AST_Dot && no_constructor_parens(this, output))
+        if (no_constructor_parens(this, output)
+            && (p instanceof AST_Dot // (new Date).getTime()
+                || p instanceof AST_Call && p.expression === this)) // (new foo)(bar)
             return true;
     });
 
@@ -529,6 +545,7 @@ function OutputStream(options) {
     });
     DEFPRINT(AST_Toplevel, function(self, output){
         display_body(self.body, true, output);
+        output.print("");
     });
     DEFPRINT(AST_LabeledStatement, function(self, output){
         self.label.print(output);

lib/parse.js

@@ -883,6 +883,8 @@ function parse($TEXT, options) {
     var function_ = function(in_statement, ctor) {
         var name = is("name") ? as_symbol(in_statement
                                           ? AST_SymbolDefun
+                                          : ctor === AST_Accessor
+                                          ? AST_SymbolAccessor
                                           : AST_SymbolLambda) : null;
         if (in_statement && !name)
             unexpected();
@@ -1158,7 +1160,7 @@ function parse($TEXT, options) {
                     a.push(new AST_ObjectGetter({
                         start : start,
                         key   : name,
-                        value : function_(false, AST_Lambda),
+                        value : function_(false, AST_Accessor),
                         end   : prev()
                     }));
                     continue;
@@ -1167,7 +1169,7 @@ function parse($TEXT, options) {
                     a.push(new AST_ObjectSetter({
                         start : start,
                         key   : name,
-                        value : function_(false, AST_Lambda),
+                        value : function_(false, AST_Accessor),
                         end   : prev()
                     }));
                     continue;

lib/scope.js

@@ -43,7 +43,7 @@
 
 "use strict";
 
-function SymbolDef(scope, orig) {
+function SymbolDef(scope, index, orig) {
     this.name = orig.name;
     this.orig = [ orig ];
     this.scope = scope;
@@ -52,15 +52,18 @@ function SymbolDef(scope, orig) {
     this.mangled_name = null;
     this.undeclared = false;
     this.constant = false;
+    this.index = index;
 };
 
 SymbolDef.prototype = {
-    unmangleable: function() {
-        return this.global || this.undeclared || this.scope.uses_eval || this.scope.uses_with;
+    unmangleable: function(options) {
+        return this.global
+            || this.undeclared
+            || (!options.eval && (this.scope.uses_eval || this.scope.uses_with));
     },
-    mangle: function() {
-        if (!this.mangled_name && !this.unmangleable())
-            this.mangled_name = this.scope.next_mangled();
+    mangle: function(options) {
+        if (!this.mangled_name && !this.unmangleable(options))
+            this.mangled_name = this.scope.next_mangled(options);
     }
 };
 
@@ -75,14 +78,17 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
     // pass 1: setup scope chaining and handle definitions
     var self = this;
     var scope = self.parent_scope = null;
-    var labels = Object.create(null);
+    var labels = new Dictionary();
+    var nesting = 0;
     var tw = new TreeWalker(function(node, descend){
         if (node instanceof AST_Scope) {
-            node.init_scope_vars();
+            node.init_scope_vars(nesting);
             var save_scope = node.parent_scope = scope;
+            ++nesting;
             scope = node;
             descend();
             scope = save_scope;
+            --nesting;
             return true;        // don't descend again in TreeWalker
         }
         if (node instanceof AST_Directive) {
@@ -97,11 +103,11 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
         }
         if (node instanceof AST_LabeledStatement) {
             var l = node.label;
-            if (labels[l.name])
+            if (labels.has(l.name))
                 throw new Error(string_template("Label {name} defined twice", l));
-            labels[l.name] = l;
+            labels.set(l.name, l);
             descend();
-            delete labels[l.name];
+            labels.del(l.name);
             return true;        // no descend again
         }
         if (node instanceof AST_SymbolDeclaration) {
@@ -115,7 +121,14 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             node.init_scope_vars();
         }
         if (node instanceof AST_SymbolLambda) {
-            scope.def_function(node);
+            //scope.def_function(node);
+            //
+            // https://github.com/mishoo/UglifyJS2/issues/24 — MSIE
+            // leaks function expression names into the containing
+            // scope.  Don't like this fix but seems we can't do any
+            // better.  IE: please die. Please!
+            (node.scope = scope.parent_scope).def_function(node);
+
             node.init.push(tw.parent());
         }
         else if (node instanceof AST_SymbolDefun) {
@@ -144,7 +157,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             scope.def_variable(node);
         }
         if (node instanceof AST_LabelRef) {
-            var sym = labels[node.name];
+            var sym = labels.get(node.name);
             if (!sym) throw new Error(string_template("Undefined label {name} [{line},{col}]", {
                 name: node.name,
                 line: node.start.line,
@@ -157,7 +170,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
 
     // pass 2: find back references and eval
     var func = null;
-    var globals = self.globals = Object.create(null);
+    var globals = self.globals = new Dictionary();
     var tw = new TreeWalker(function(node, descend){
         if (node instanceof AST_Lambda) {
             var prev_func = func;
@@ -175,12 +188,12 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
             var sym = node.scope.find_variable(name);
             if (!sym) {
                 var g;
-                if (globals[name]) {
-                    g = globals[name];
+                if (globals.has(name)) {
+                    g = globals.get(name);
                 } else {
-                    g = new SymbolDef(self, node);
+                    g = new SymbolDef(self, globals.size(), node);
                     g.undeclared = true;
-                    globals[name] = g;
+                    globals.set(name, g);
                 }
                 node.thedef = g;
                 if (name == "eval" && tw.parent() instanceof AST_Call) {
@@ -200,15 +213,16 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(){
     self.walk(tw);
 });
 
-AST_Scope.DEFMETHOD("init_scope_vars", function(){
+AST_Scope.DEFMETHOD("init_scope_vars", function(nesting){
     this.directives = [];     // contains the directives defined in this scope, i.e. "use strict"
-    this.variables = Object.create(null); // map name to AST_SymbolVar (variables defined in this scope; includes functions)
-    this.functions = Object.create(null); // map name to AST_SymbolDefun (functions defined in this scope)
+    this.variables = new Dictionary(); // map name to AST_SymbolVar (variables defined in this scope; includes functions)
+    this.functions = new Dictionary(); // map name to AST_SymbolDefun (functions defined in this scope)
     this.uses_with = false;   // will be set to true if this or some nested scope uses the `with` statement
     this.uses_eval = false;   // will be set to true if this or nested scope uses the global `eval`
     this.parent_scope = null; // the parent scope
     this.enclosed = [];       // a list of variables from this or outer scope(s) that are referenced from this or inner scopes
     this.cname = -1;          // the current index for mangling functions/variables
+    this.nesting = nesting;   // the nesting level of this scope (0 means toplevel)
 });
 
 AST_Scope.DEFMETHOD("strict", function(){
@@ -216,7 +230,7 @@ AST_Scope.DEFMETHOD("strict", function(){
 });
 
 AST_Lambda.DEFMETHOD("init_scope_vars", function(){
-    AST_Scope.prototype.init_scope_vars.call(this);
+    AST_Scope.prototype.init_scope_vars.apply(this, arguments);
     this.uses_arguments = false;
 });
 
@@ -229,6 +243,7 @@ AST_SymbolRef.DEFMETHOD("reference", function() {
         if (s === def.scope) break;
         s = s.parent_scope;
     }
+    this.frame = this.scope.nesting - def.scope.nesting;
 });
 
 AST_SymbolDeclaration.DEFMETHOD("init_scope_vars", function(){
@@ -245,7 +260,7 @@ AST_LabelRef.DEFMETHOD("reference", function(){
 
 AST_Scope.DEFMETHOD("find_variable", function(name){
     if (name instanceof AST_Symbol) name = name.name;
-    return this.variables[name]
+    return this.variables.get(name)
         || (this.parent_scope && this.parent_scope.find_variable(name));
 });
 
@@ -255,23 +270,23 @@ AST_Scope.DEFMETHOD("has_directive", function(value){
 });
 
 AST_Scope.DEFMETHOD("def_function", function(symbol){
-    this.functions[symbol.name] = this.def_variable(symbol);
+    this.functions.set(symbol.name, this.def_variable(symbol));
 });
 
 AST_Scope.DEFMETHOD("def_variable", function(symbol){
     var def;
-    if (!this.variables[symbol.name]) {
-        def = new SymbolDef(this, symbol);
-        this.variables[symbol.name] = def;
+    if (!this.variables.has(symbol.name)) {
+        def = new SymbolDef(this, this.variables.size(), symbol);
+        this.variables.set(symbol.name, def);
         def.global = !this.parent_scope;
     } else {
-        def = this.variables[symbol.name];
+        def = this.variables.get(symbol.name);
         def.orig.push(symbol);
     }
     return symbol.thedef = def;
 });
 
-AST_Scope.DEFMETHOD("next_mangled", function(){
+AST_Scope.DEFMETHOD("next_mangled", function(options){
     var ext = this.enclosed, n = ext.length;
     out: while (true) {
         var m = base54(++this.cname);
@@ -281,7 +296,7 @@ AST_Scope.DEFMETHOD("next_mangled", function(){
         // inner scopes.
         for (var i = n; --i >= 0;) {
             var sym = ext[i];
-            var name = sym.mangled_name || (sym.unmangleable() && sym.name);
+            var name = sym.mangled_name || (sym.unmangleable(options) && sym.name);
             if (m == name) continue out;
         }
         return m;
@@ -293,8 +308,13 @@ AST_Scope.DEFMETHOD("references", function(sym){
     return this.enclosed.indexOf(sym) < 0 ? null : sym;
 });
 
-AST_Symbol.DEFMETHOD("unmangleable", function(){
-    return this.definition().unmangleable();
+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
@@ -329,7 +349,8 @@ AST_Symbol.DEFMETHOD("global", function(){
 
 AST_Toplevel.DEFMETHOD("mangle_names", function(options){
     options = defaults(options, {
-        except : []
+        except : [],
+        eval   : false,
     });
     // We only need to mangle declaration nodes.  Special logic wired
     // into the code generator will display the mangled name if it's
@@ -347,16 +368,11 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
         }
         if (node instanceof AST_Scope) {
             var p = tw.parent();
-            var is_setget = p instanceof AST_ObjectSetter || p instanceof AST_ObjectGetter;
-            var a = node.variables;
-            for (var i in a) {
-                var symbol = a[i];
-                if (!(is_setget && symbol instanceof AST_SymbolLambda)) {
-                    if (options.except.indexOf(symbol.name) < 0) {
-                        to_mangle.push(symbol);
-                    }
+            node.variables.each(function(symbol){
+                if (options.except.indexOf(symbol.name) < 0) {
+                    to_mangle.push(symbol);
                 }
-            }
+            });
             return;
         }
         if (node instanceof AST_Label) {
@@ -370,7 +386,7 @@ AST_Toplevel.DEFMETHOD("mangle_names", function(options){
     to_mangle.forEach(function(def){ def.mangle(options) });
 });
 
-AST_Toplevel.DEFMETHOD("compute_char_frequency", function(){
+AST_Toplevel.DEFMETHOD("compute_char_frequency", function(options){
     var tw = new TreeWalker(function(node){
         if (node instanceof AST_Constant)
             base54.consider(node.print_to_string());
@@ -428,7 +444,7 @@ AST_Toplevel.DEFMETHOD("compute_char_frequency", function(){
             base54.consider("catch");
         else if (node instanceof AST_Finally)
             base54.consider("finally");
-        else if (node instanceof AST_Symbol && node.unmangleable())
+        else if (node instanceof AST_Symbol && node.unmangleable(options))
             base54.consider(node.name);
         else if (node instanceof AST_Unary || node instanceof AST_Binary)
             base54.consider(node.operator);

lib/utils.js

@@ -244,3 +244,37 @@ function makePredicate(words) {
     }
     return new Function("str", f);
 };
+
+function Dictionary() {
+    this._values = Object.create(null);
+    this._size = 0;
+};
+Dictionary.prototype = {
+    set: function(key, val) {
+        if (!this.has(key)) ++this._size;
+        this._values["$" + key] = val;
+        return this;
+    },
+    get: function(key) { return this._values["$" + key] },
+    del: function(key) {
+        if (this.has(key)) {
+            --this._size;
+            delete this._values["$" + key];
+        }
+        return this;
+    },
+    has: function(key) { return ("$" + key) in this._values },
+    each: function(f) {
+        for (var i in this._values)
+            f(this._values[i], i.substr(1));
+    },
+    size: function() {
+        return this._size;
+    },
+    map: function(f) {
+        var ret = [];
+        for (var i in this._values)
+            ret.push(f(this._values[i], i.substr(1)));
+        return ret;
+    }
+};

package.json

@@ -3,7 +3,7 @@
     "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
     "homepage": "http://lisperator.net/uglifyjs",
     "main": "tools/node.js",
-    "version": "2.1.2",
+    "version": "2.1.7",
     "engines": { "node" : ">=0.4.0" },
     "maintainers": [{
         "name": "Mihai Bazon",

test/compress/issue-22.js

@@ -0,0 +1,17 @@
+return_with_no_value_in_if_body: {
+    options = { conditionals: true };
+    input: {
+        function foo(bar) {
+            if (bar) {
+                return;
+            } else {
+                return 1;
+            }
+        }
+    }
+    expect: {
+        function foo (bar) {
+            return bar ? void 0 : 1;
+        }
+    }
+}

test/compress/sequences.js

@@ -87,3 +87,75 @@ make_sequences_4: {
         with (x = 5, obj);
     }
 }
+
+lift_sequences_1: {
+    options = { sequences: true };
+    input: {
+        foo = !(x(), y(), bar());
+    }
+    expect: {
+        x(), y(), foo = !bar();
+    }
+}
+
+lift_sequences_2: {
+    options = { sequences: true, evaluate: true };
+    input: {
+        q = 1 + (foo(), bar(), 5) + 7 * (5 / (3 - (a(), (QW=ER), c(), 2))) - (x(), y(), 5);
+    }
+    expect: {
+        foo(), bar(), a(), QW = ER, c(), x(), y(), q = 36
+    }
+}
+
+lift_sequences_3: {
+    options = { sequences: true, conditionals: true };
+    input: {
+        x = (foo(), bar(), baz()) ? 10 : 20;
+    }
+    expect: {
+        foo(), bar(), x = baz() ? 10 : 20;
+    }
+}
+
+lift_sequences_4: {
+    options = { side_effects: true };
+    input: {
+        x = (foo, bar, baz);
+    }
+    expect: {
+        x = baz;
+    }
+}
+
+for_sequences: {
+    options = { sequences: true };
+    input: {
+        // 1
+        foo();
+        bar();
+        for (; false;);
+        // 2
+        foo();
+        bar();
+        for (x = 5; false;);
+        // 3
+        x = (foo in bar);
+        for (; false;);
+        // 4
+        x = (foo in bar);
+        for (y = 5; false;);
+    }
+    expect: {
+        // 1
+        for (foo(), bar(); false;);
+        // 2
+        for (foo(), bar(), x = 5; false;);
+        // 3
+        x = (foo in bar);
+        for (; false;);
+        // 4
+        x = (foo in bar);
+        for (y = 5; false;);
+    }
+}

tools/node.js

@@ -1,16 +1,5 @@
 var path = require("path");
 var fs = require("fs");
-
-// Avoid NodeJS warning.
-//
-// There's a --no-deprecation command line argument supported by
-// NodeJS, but that's tricky to use, so I'd like to set it from the
-// program itself.  Turns out you need to set `process.noDeprecation`,
-// but by the time you can set that the `path` module is already
-// loaded and `path.existsSync` is already changed to display that
-// warning, therefore here's the poor solution:
-path.existsSync = fs.existsSync;
-
 var vm = require("vm");
 var sys = require("util");