harmony-v3.1.9

fixes #2468

README.md

@@ -706,6 +706,11 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   Specify `"strict"` to treat `foo.bar` as side-effect-free only when
   `foo` is certain to not throw, i.e. not `null` or `undefined`.
 
+- `reduce_funcs` (default: `true`) -- Allows single-use functions
+  to be inlined as function expressions when permissible.
+  Enabled by default.  Option depends on `reduce_vars` being enabled.
+  For speed critical code this option should be disabled.
+
 - `reduce_vars` (default: `true`) -- Improve optimization on variables assigned with and
   used as constant values.
 

lib/compress.js

@@ -78,6 +78,7 @@ function Compressor(options, false_by_default) {
         properties    : !false_by_default,
         pure_getters  : !false_by_default && "strict",
         pure_funcs    : null,
+        reduce_funcs  : !false_by_default,
         reduce_vars   : !false_by_default,
         sequences     : !false_by_default,
         side_effects  : !false_by_default,
@@ -156,7 +157,9 @@ merge(Compressor.prototype, {
         }
         var passes = +this.options.passes || 1;
         var last_count = 1 / 0;
+        var mangle = { ie8: this.option("ie8") };
         for (var pass = 0; pass < passes; pass++) {
+            node.figure_out_scope(mangle);
             if (pass > 0 || this.option("reduce_vars"))
                 node.reset_opt_flags(this);
             node = node.transform(this);
@@ -291,7 +294,7 @@ merge(Compressor.prototype, {
         self.transform(tt);
     });
 
-    AST_Node.DEFMETHOD("reset_opt_flags", function(compressor) {
+    AST_Toplevel.DEFMETHOD("reset_opt_flags", function(compressor) {
         var reduce_vars = compressor.option("reduce_vars");
         var unused = compressor.option("unused");
         // Stack of look-up tables to keep track of whether a `SymbolDef` has been
@@ -318,16 +321,16 @@ merge(Compressor.prototype, {
                 if (node instanceof AST_SymbolRef) {
                     var d = node.definition();
                     d.references.push(node);
+                    var value;
                     if (d.fixed === undefined || !safe_to_read(d) || d.single_use == "m") {
                         d.fixed = false;
                     } else if (d.fixed) {
-                        var value = node.fixed_value();
-                        if (unused && !compressor.exposed(d)) {
-                            d.single_use = value
-                                && d.references.length == 1
-                                && loop_ids[d.id] === in_loop
-                                && d.scope === node.scope
-                                && value.is_constant_expression();
+                        value = node.fixed_value();
+                        if (value && ref_once(d) && !compressor.exposed(d)) {
+                            d.single_use = value instanceof AST_Lambda
+                                || d.scope === node.scope && value.is_constant_expression();
+                        } else {
+                            d.single_use = false;
                         }
                         if (is_modified(node, value, 0, is_immutable(value))) {
                             if (d.single_use) {
@@ -335,10 +338,9 @@ merge(Compressor.prototype, {
                             } else {
                                 d.fixed = false;
                             }
-                        } else {
-                            mark_escaped(d, node, value, 0);
                         }
                     }
+                    mark_escaped(d, node, value, 0);
                 }
                 if (node instanceof AST_SymbolCatch) {
                     node.definition().fixed = false;
@@ -389,7 +391,9 @@ merge(Compressor.prototype, {
                         d.fixed = false;
                     } else {
                         d.fixed = node;
+                        loop_ids[d.id] = in_loop;
                         mark(d, true);
+                        d.single_use = ref_once(d);
                     }
                     var save_ids = safe_ids;
                     safe_ids = Object.create(null);
@@ -542,6 +546,7 @@ merge(Compressor.prototype, {
                 }
                 return true;
             }
+            return def.fixed instanceof AST_Defun;
         }
 
         function safe_to_assign(def, value) {
@@ -567,7 +572,7 @@ merge(Compressor.prototype, {
         function reset_def(def) {
             def.direct_access = false;
             def.escaped = false;
-            if (def.scope.uses_eval) {
+            if (def.scope.uses_eval || def.scope.uses_with) {
                 def.fixed = false;
             } else if (def.orig[0] instanceof AST_SymbolConst || !compressor.exposed(def)) {
                 def.fixed = undefined;
@@ -579,8 +584,19 @@ merge(Compressor.prototype, {
             def.single_use = undefined;
         }
 
+        function ref_once(def) {
+            return unused
+                && !def.scope.uses_eval
+                && !def.scope.uses_with
+                && def.references.length == 1
+                && loop_ids[def.id] === in_loop;
+        }
+
         function is_immutable(value) {
-            return value && (value.is_constant() || value instanceof AST_Lambda);
+            if (!value) return false;
+            return value.is_constant()
+                || value instanceof AST_Lambda
+                || value instanceof AST_This;
         }
 
         function read_property(obj, key) {
@@ -608,10 +624,13 @@ merge(Compressor.prototype, {
                 || !immutable
                     && parent instanceof AST_Call
                     && parent.expression === node
-                    && (!(value instanceof AST_Function) || value.contains_this())) {
+                    && (!(value instanceof AST_Function) || value.contains_this(parent))) {
                 return true;
-            } else if (parent instanceof AST_Array || parent instanceof AST_Object) {
+            } else if (parent instanceof AST_Array) {
                 return is_modified(parent, parent, level + 1);
+            } else if (parent instanceof AST_ObjectKeyVal && node === parent.value) {
+                var obj = tw.parent(level + 1);
+                return is_modified(obj, obj, level + 2);
             } else if (parent instanceof AST_PropAccess && parent.expression === node) {
                 return !immutable && is_modified(parent, read_property(value, parent.property), level + 1);
             }
@@ -619,15 +638,19 @@ merge(Compressor.prototype, {
 
         function mark_escaped(d, node, value, level) {
             var parent = tw.parent(level);
-            if (value instanceof AST_Constant || value instanceof AST_Function) return;
+            if (value instanceof AST_Constant || value instanceof AST_ClassExpression) return;
+            if (level > 0 && value instanceof AST_Function) return;
             if (parent instanceof AST_Assign && parent.operator == "=" && node === parent.right
                 || parent instanceof AST_Call && node !== parent.expression
                 || parent instanceof AST_Return && node === parent.value && node.scope !== d.scope
                 || parent instanceof AST_VarDef && node === parent.value) {
                 d.escaped = true;
                 return;
-            } else if (parent instanceof AST_Array || parent instanceof AST_Object) {
+            } else if (parent instanceof AST_Array) {
                 mark_escaped(d, parent, parent, level + 1);
+            } else if (parent instanceof AST_ObjectKeyVal && node === parent.value) {
+                var obj = tw.parent(level + 1);
+                mark_escaped(d, obj, obj, level + 2);
             } else if (parent instanceof AST_PropAccess && node === parent.expression) {
                 value = read_property(value, parent.property);
                 mark_escaped(d, parent, value, level + 1);
@@ -811,6 +834,14 @@ merge(Compressor.prototype, {
             || compressor.option("unsafe") && global_names(this.name);
     });
 
+    function drop_decl(def) {
+        def._eliminiated = (def._eliminiated || 0) + 1;
+        if (def.orig.length == def._eliminiated) {
+            def.scope.functions.del(def.name);
+            def.scope.variables.del(def.name);
+        }
+    }
+
     function tighten_body(statements, compressor) {
         var CHANGED, max_iter = 10;
         do {
@@ -844,6 +875,7 @@ merge(Compressor.prototype, {
         function collapse(statements, compressor) {
             var scope = compressor.find_parent(AST_Scope).get_defun_scope();
             if (scope.uses_eval || scope.uses_with) return statements;
+            var args;
             var candidates = [];
             var stat_index = statements.length;
             while (--stat_index >= 0) {
@@ -864,7 +896,7 @@ merge(Compressor.prototype, {
                     var one_off = lhs instanceof AST_Symbol && lhs.definition().references.length == 1;
                     var side_effects = value_has_side_effects(candidate);
                     var hit = candidate.name instanceof AST_SymbolFunarg;
-                    var abort = false, replaced = false;
+                    var abort = false, replaced = false, can_replace = !args || !hit;
                     var tt = new TreeTransformer(function(node, descend) {
                         if (abort) return node;
                         // Skip nodes before `candidate` as quickly as possible
@@ -891,7 +923,8 @@ merge(Compressor.prototype, {
                             return node;
                         }
                         // Replace variable with assignment when found
-                        if (!(node instanceof AST_SymbolDeclaration)
+                        if (can_replace
+                            && !(node instanceof AST_SymbolDeclaration)
                             && !is_lhs(node, parent)
                             && lhs.equivalent_to(node)) {
                             CHANGED = replaced = abort = true;
@@ -942,6 +975,12 @@ merge(Compressor.prototype, {
                         // Skip (non-executed) functions and (leading) default case in switch statements
                         if (node instanceof AST_Default || node instanceof AST_Scope) return node;
                     });
+                    if (!can_replace) {
+                        for (var j = compressor.self().argnames.lastIndexOf(candidate.__name || candidate.name) + 1; j < args.length; j++) {
+                            args[j].transform(tt);
+                        }
+                        can_replace = true;
+                    }
                     for (var i = stat_index; !abort && i < statements.length; i++) {
                         statements[i].transform(tt);
                     }
@@ -987,9 +1026,16 @@ merge(Compressor.prototype, {
                     })) {
                     var fn_strict = compressor.has_directive("use strict");
                     if (fn_strict && fn.body.indexOf(fn_strict) < 0) fn_strict = false;
+                    var len = fn.argnames.length;
+                    args = iife.args.slice(len);
                     var names = Object.create(null);
-                    for (var i = fn.argnames.length; --i >= 0;) {
+                    for (var i = len; --i >= 0;) {
                         var sym = fn.argnames[i];
+                        var arg = iife.args[i];
+                        args.unshift(make_node(AST_VarDef, sym, {
+                            name: sym,
+                            value: arg
+                        }));
                         if (sym.name in names) continue;
                         names[sym.name] = true;
                         if (sym instanceof AST_Expansion) {
@@ -1003,9 +1049,9 @@ merge(Compressor.prototype, {
                                         elements: elements
                                     })
                                 }));
+                                candidates[0].__name = sym;
                             }
                         } else {
-                            var arg = iife.args[i];
                             if (!arg) arg = make_node(AST_Undefined, sym).transform(compressor);
                             else if (has_overlapping_symbol(fn, arg, fn_strict)) arg = null;
                             if (arg) candidates.unshift(make_node(AST_VarDef, sym, {
@@ -1023,7 +1069,8 @@ merge(Compressor.prototype, {
                     candidates.push(expr);
                 } else if (expr instanceof AST_Sequence) {
                     expr.expressions.forEach(extract_candidates);
-                } else if (expr instanceof AST_Definitions) {
+                } else if (expr instanceof AST_Definitions
+                    && (compressor.option("unused") || !(expr instanceof AST_Const))) {
                     expr.definitions.forEach(function(var_def) {
                         if (var_def.value) candidates.push(var_def);
                     });
@@ -1037,7 +1084,8 @@ merge(Compressor.prototype, {
             function get_lhs(expr) {
                 if (expr instanceof AST_VarDef && expr.name instanceof AST_SymbolDeclaration) {
                     var def = expr.name.definition();
-                    if (def.orig.length > 1 && !(expr.name instanceof AST_SymbolFunarg)
+                    if (def.orig.length - (def._eliminiated || 0) > 1
+                            && !(expr.name instanceof AST_SymbolFunarg)
                         || def.references.length == 1 && !compressor.exposed(def)) {
                         return make_node(AST_SymbolRef, expr.name, expr.name);
                     }
@@ -1047,6 +1095,10 @@ merge(Compressor.prototype, {
                 }
             }
 
+            function get_rvalue(expr) {
+                return expr[expr instanceof AST_Assign ? "right" : "value"];
+            }
+
             function get_lvalues(expr) {
                 var lvalues = Object.create(null);
                 if (expr instanceof AST_Unary) return lvalues;
@@ -1057,7 +1109,7 @@ merge(Compressor.prototype, {
                         lvalues[sym.name] = lvalues[sym.name] || is_lhs(node, tw.parent());
                     }
                 });
-                expr[expr instanceof AST_Assign ? "right" : "value"].walk(tw);
+                get_rvalue(expr).walk(tw);
                 return lvalues;
             }
 
@@ -1083,10 +1135,12 @@ merge(Compressor.prototype, {
                 var found = false;
                 return statements[stat_index].transform(new TreeTransformer(function(node, descend, in_list) {
                     if (found) return node;
-                    if (node === expr) {
+                    if (node === expr || node.body === expr) {
                         found = true;
                         if (node instanceof AST_VarDef) {
-                            remove(node.name.definition().orig, node.name);
+                            drop_decl(node.name.definition());
+                            node.value = null;
+                            return node;
                         }
                         return in_list ? MAP.skip : null;
                     }
@@ -1095,16 +1149,12 @@ merge(Compressor.prototype, {
                       case 0: return null;
                       case 1: return node.expressions[0];
                     }
-                    if (node instanceof AST_Definitions && node.definitions.length == 0
-                        || node instanceof AST_SimpleStatement && !node.body) {
-                        return null;
-                    }
                 }));
             }
 
             function value_has_side_effects(expr) {
                 if (expr instanceof AST_Unary) return false;
-                return expr[expr instanceof AST_Assign ? "right" : "value"].has_side_effects(compressor);
+                return get_rvalue(expr).has_side_effects(compressor);
             }
 
             function references_in_scope(def) {
@@ -2261,18 +2311,25 @@ merge(Compressor.prototype, {
         }
         def(AST_Node, return_false);
         def(AST_Constant, return_true);
-        def(AST_Function, function(){
+        def(AST_Lambda, function(scope){
             var self = this;
             var result = true;
             self.walk(new TreeWalker(function(node) {
                 if (!result) return true;
                 if (node instanceof AST_SymbolRef) {
                     var def = node.definition();
-                    if (self.enclosed.indexOf(def) >= 0
-                        && self.variables.get(def.name) !== def) {
+                    if (member(def, self.enclosed)
+                        && !self.variables.has(def.name)) {
+                        if (scope) {
+                            var scope_def = scope.find_variable(node);
+                            if (def.undeclared ? !scope_def : scope_def === def) {
+                                result = "f";
+                                return true;
+                            }
+                        }
                         result = false;
-                        return true;
                     }
+                    return true;
                 }
             }));
             return result;
@@ -2353,7 +2410,7 @@ merge(Compressor.prototype, {
                 || can_be_evicted_from_block(self.body[0])) {
                 return self.body[0];
             }
-          break;
+            break;
           case 0: return make_node(AST_EmptyStatement, self);
         }
         return self;
@@ -2389,75 +2446,80 @@ merge(Compressor.prototype, {
         // this scope (not in nested scopes).
         var scope = this;
         var tw = new TreeWalker(function(node, descend){
-            if (node !== self) {
-                if (node instanceof AST_Defun || node instanceof AST_DefClass) {
-                    var in_export = tw.parent() instanceof AST_Export;
-                    if (in_export || !drop_funcs && scope === self) {
-                        var node_def = node.name.definition();
-                        if (node_def.global && !(node_def.id in in_use_ids)) {
-                            in_use_ids[node_def.id] = true;
-                            in_use.push(node_def);
-                        }
-                    }
-                    initializations.add(node.name.name, node);
-                    return true; // don't go in nested scopes
-                }
-                if (node instanceof AST_Definitions && scope === self) {
-                    var in_export = tw.parent() instanceof AST_Export;
-                    node.definitions.forEach(function(def){
-                        if (def.name instanceof AST_SymbolVar) {
-                            var_defs_by_id.add(def.name.definition().id, def);
-                        }
-                        if (in_export || !drop_vars) {
-                            def.name.walk(new TreeWalker(function(node) {
-                                if (node instanceof AST_SymbolDeclaration) {
-                                    var def = node.definition();
-                                    if ((in_export || def.global) && !(def.id in in_use_ids)) {
-                                        in_use_ids[def.id] = true;
-                                        in_use.push(def);
-                                    }
-                                }
-                            }));
-                        }
-                        if (def.value) {
-                            if (def.name instanceof AST_Destructuring) {
-                                var destructuring_cache = destructuring_value;
-                                destructuring_value = def.value;
-                                def.walk(tw);
-                                destructuring_value = destructuring_cache;
-                            } else {
-                                initializations.add(def.name.name, def.value);
-                            }
-                            if (def.value.has_side_effects(compressor)) {
-                                def.value.walk(tw);
-                            }
-                        }
-                    });
-                    return true;
-                }
-                if (assign_as_unused(node) instanceof AST_SymbolRef && scope === self
-                    && !is_ref_of(node.left, AST_SymbolBlockDeclaration)) {
-                    if (node instanceof AST_Assign) node.right.walk(tw);
-                    return true;
-                }
-                if (node instanceof AST_SymbolRef) {
-                    var node_def = node.definition();
-                    if (!(node_def.id in in_use_ids)) {
+            if (node === self) return;
+            if (node instanceof AST_Defun || node instanceof AST_DefClass) {
+                var in_export = tw.parent() instanceof AST_Export;
+                if (in_export || !drop_funcs && scope === self) {
+                    var node_def = node.name.definition();
+                    if (node_def.global && !(node_def.id in in_use_ids)) {
                         in_use_ids[node_def.id] = true;
                         in_use.push(node_def);
                     }
-                    return true;
                 }
-                if (node instanceof AST_Scope) {
-                    var save_scope = scope;
-                    scope = node;
-                    descend();
-                    scope = save_scope;
-                    return true;
-                }
-                if (node.destructuring && destructuring_value) {
-                    initializations.add(node.name, destructuring_value);
+                initializations.add(node.name.name, node);
+                return true; // don't go in nested scopes
+            }
+            if (node instanceof AST_SymbolFunarg && scope === self) {
+                var_defs_by_id.add(node.definition().id, node);
+            }
+            if (node instanceof AST_Definitions && scope === self) {
+                var in_export = tw.parent() instanceof AST_Export;
+                node.definitions.forEach(function(def){
+                    if (def.name instanceof AST_SymbolVar) {
+                        var_defs_by_id.add(def.name.definition().id, def);
+                    }
+                    if (in_export || !drop_vars) {
+                        def.name.walk(new TreeWalker(function(node) {
+                            if (node instanceof AST_SymbolDeclaration) {
+                                var def = node.definition();
+                                if ((in_export || def.global) && !(def.id in in_use_ids)) {
+                                    in_use_ids[def.id] = true;
+                                    in_use.push(def);
+                                }
+                            }
+                        }));
+                    }
+                    if (def.value) {
+                        if (def.name instanceof AST_Destructuring) {
+                            var destructuring_cache = destructuring_value;
+                            destructuring_value = def.value;
+                            def.walk(tw);
+                            destructuring_value = destructuring_cache;
+                        } else {
+                            initializations.add(def.name.name, def.value);
+                        }
+                        if (def.value.has_side_effects(compressor)) {
+                            def.value.walk(tw);
+                        }
+                    }
+                });
+                return true;
+            }
+            var sym;
+            if (scope === self
+                && (sym = assign_as_unused(node)) instanceof AST_SymbolRef
+                && !is_ref_of(node.left, AST_SymbolBlockDeclaration)
+                && self.variables.get(sym.name) === sym.definition()) {
+                if (node instanceof AST_Assign) node.right.walk(tw);
+                return true;
+            }
+            if (node instanceof AST_SymbolRef) {
+                var node_def = node.definition();
+                if (!(node_def.id in in_use_ids)) {
+                    in_use_ids[node_def.id] = true;
+                    in_use.push(node_def);
                 }
+                return true;
+            }
+            if (node instanceof AST_Scope) {
+                var save_scope = scope;
+                scope = node;
+                descend();
+                scope = save_scope;
+                return true;
+            }
+            if (node.destructuring && destructuring_value) {
+                initializations.add(node.name, destructuring_value);
             }
         });
         self.walk(tw);
@@ -2522,9 +2584,11 @@ merge(Compressor.prototype, {
                     }
                 }
                 if ((node instanceof AST_Defun || node instanceof AST_DefClass) && node !== self) {
-                    var keep = (node.name.definition().id in in_use_ids) || !drop_funcs && node.name.definition().global;
+                    var def = node.name.definition();
+                    var keep = (def.id in in_use_ids) || !drop_funcs && def.global;
                     if (!keep) {
                         compressor[node.name.unreferenced() ? "warn" : "info"]("Dropping unused function {name} [{file}:{line},{col}]", template(node.name));
+                        drop_decl(def);
                         return make_node(AST_EmptyStatement, node);
                     }
                     return node;
@@ -2549,7 +2613,7 @@ merge(Compressor.prototype, {
                                 if (var_defs.length > 1 && !def.value) {
                                     compressor.warn("Dropping duplicated definition of variable {name} [{file}:{line},{col}]", template(def.name));
                                     remove(var_defs, def);
-                                    remove(sym.orig, def.name);
+                                    drop_decl(sym);
                                     return;
                                 }
                             }
@@ -2582,7 +2646,7 @@ merge(Compressor.prototype, {
                             } else {
                                 compressor[def.name.unreferenced() ? "warn" : "info"]("Dropping unused variable {name} [{file}:{line},{col}]", template(def.name));
                             }
-                            remove(sym.orig, def.name);
+                            drop_decl(sym);
                         }
                     });
                     if (head.length == 0 && tail.length == 1 && tail[0].name instanceof AST_SymbolVar) {
@@ -2591,7 +2655,7 @@ merge(Compressor.prototype, {
                             var def = tail.pop();
                             compressor.warn("Converting duplicated definition of variable {name} to assignment [{file}:{line},{col}]", template(def.name));
                             remove(var_defs, def);
-                            remove(def.name.definition().orig, def.name);
+                            drop_decl(def.name.definition());
                             side_effects.unshift(make_node(AST_Assign, def, {
                                 operator: "=",
                                 left: make_node(AST_SymbolRef, def.name, def.name),
@@ -2623,8 +2687,7 @@ merge(Compressor.prototype, {
                     var def = assign_as_unused(node);
                     if (def instanceof AST_SymbolRef
                         && !((def = def.definition()).id in in_use_ids)
-                        && (drop_vars || !def.global)
-                        && self.variables.get(def.name) === def) {
+                        && (drop_vars || !def.global)) {
                         if (node instanceof AST_Assign) {
                             return maintain_this_binding(parent, node, node.right.transform(tt));
                         }
@@ -2833,7 +2896,8 @@ merge(Compressor.prototype, {
         self.variables.each(function(def, name) {
             var_names[name] = true;
         });
-        return self.transform(new TreeTransformer(function(node) {
+        var tt = new TreeTransformer(function(node) {
+            if (node instanceof AST_Definitions && tt.parent() instanceof AST_Export) return node;
             if (node instanceof AST_VarDef) {
                 var sym = node.name, def, value;
                 if (sym.scope === self
@@ -2884,7 +2948,8 @@ merge(Compressor.prototype, {
                 var_names[name] = true;
                 return new_var;
             }
-        }));
+        });
+        return self.transform(tt);
     });
 
     // drop_side_effect_free()
@@ -3440,7 +3505,7 @@ merge(Compressor.prototype, {
                 });
                 a.push(var_);
             }
-            remove(def.name.definition().orig, def.name);
+            drop_decl(def.name.definition());
             return a;
         }, []);
         if (assignments.length == 0) return null;
@@ -3723,6 +3788,7 @@ merge(Compressor.prototype, {
                 && !exp.uses_arguments
                 && !exp.uses_eval
                 && (exp.body instanceof AST_Node || exp.body.length == 1)
+                && !exp.contains_this()
                 && all(exp.argnames, function(arg) {
                     if (arg instanceof AST_Expansion) return arg.expression.__unused;
                     return arg.__unused;
@@ -3737,23 +3803,6 @@ merge(Compressor.prototype, {
                         expression: stat.body
                     });
                 }
-                if (value) {
-                    var tw = new TreeWalker(function(node) {
-                        if (!value) return true;
-                        if (node instanceof AST_SymbolRef) {
-                            var ref = node.scope.find_variable(node);
-                            if (ref && ref.scope.parent_scope === fn.parent_scope) {
-                                value = null;
-                                return true;
-                            }
-                        }
-                        if (node instanceof AST_This && !tw.find_parent(AST_Scope)) {
-                            value = null;
-                            return true;
-                        }
-                    });
-                    value.walk(tw);
-                }
                 if (value) {
                     var args = self.args.concat(value);
                     return make_sequence(self, args).optimize(compressor);
@@ -4043,7 +4092,8 @@ merge(Compressor.prototype, {
     function is_object(node) {
         return node instanceof AST_Array
             || node instanceof AST_Lambda
-            || node instanceof AST_Object;
+            || node instanceof AST_Object
+            || node instanceof AST_Class;
     }
 
     OPT(AST_Binary, function(self, compressor){
@@ -4423,6 +4473,17 @@ merge(Compressor.prototype, {
         return self;
     });
 
+    function recursive_ref(compressor, def) {
+        var node;
+        for (var i = 0; node = compressor.parent(i); i++) {
+            if (node instanceof AST_Lambda) {
+                var name = node.name;
+                if (name && name.definition() === def) break;
+            }
+        }
+        return node;
+    }
+
     OPT(AST_SymbolRef, function(self, compressor){
         var def = self.resolve_defines(compressor);
         if (def) {
@@ -4448,49 +4509,68 @@ merge(Compressor.prototype, {
             if (fixed instanceof AST_Defun) {
                 d.fixed = fixed = make_node(AST_Function, fixed, fixed);
             }
-            if (compressor.option("unused")
-                && fixed
-                && d.references.length == 1
-                && (d.single_use || is_func_expr(fixed)
-                    && !(d.scope.uses_arguments && d.orig[0] instanceof AST_SymbolFunarg)
-                    && !d.scope.uses_eval
-                    && compressor.find_parent(AST_Scope) === fixed.parent_scope)) {
+            if (d.single_use && fixed instanceof AST_Function) {
+                if (!compressor.option("reduce_funcs") && d.scope !== self.scope) {
+                    d.single_use = false;
+                } else if (d.escaped && d.scope !== self.scope || recursive_ref(compressor, d)) {
+                    d.single_use = false;
+                } else if (d.scope !== self.scope || d.orig[0] instanceof AST_SymbolFunarg) {
+                    d.single_use = fixed.is_constant_expression(self.scope);
+                    if (d.single_use == "f") {
+                        var scope = self.scope;
+                        do {
+                            if (scope.name) scope.name.definition().single_use = false;
+                        } while (scope = scope.parent_scope);
+                    }
+                }
+            }
+            if (d.single_use && fixed) {
                 var value = fixed.optimize(compressor);
                 return value === fixed ? fixed.clone(true) : value;
             }
-            if (compressor.option("evaluate") && fixed) {
-                if (d.should_replace === undefined) {
-                    var init = fixed.evaluate(compressor);
-                    if (init !== fixed && (compressor.option("unsafe_regexp") || !(init instanceof RegExp))) {
-                        init = make_node_from_constant(init, fixed);
-                        var value_length = init.optimize(compressor).print_to_string().length;
-                        var fn;
-                        if (has_symbol_ref(fixed)) {
-                            fn = function() {
-                                var result = init.optimize(compressor);
-                                return result === init ? result.clone(true) : result;
-                            };
-                        } else {
-                            value_length = Math.min(value_length, fixed.print_to_string().length);
-                            fn = function() {
-                                var result = best_of_expression(init.optimize(compressor), fixed);
-                                return result === init || result === fixed ? result.clone(true) : result;
-                            };
-                        }
-                        var name_length = d.name.length;
-                        var overhead = 0;
-                        if (compressor.option("unused") && !compressor.exposed(d)) {
-                            overhead = (name_length + 2 + value_length) / d.references.length;
-                        }
-                        d.should_replace = value_length <= name_length + overhead ? fn : false;
-                    } else {
-                        d.should_replace = false;
+            if (fixed && d.should_replace === undefined) {
+                var init;
+                if (fixed instanceof AST_This) {
+                    if (!(d.orig[0] instanceof AST_SymbolFunarg)
+                        && all(d.references, function(ref) {
+                            return d.scope === ref.scope;
+                        })) {
+                        init = fixed;
+                    }
+                } else {
+                    var ev = fixed.evaluate(compressor);
+                    if (ev !== fixed && (compressor.option("unsafe_regexp") || !(ev instanceof RegExp))) {
+                        init = make_node_from_constant(ev, fixed);
                     }
                 }
-                if (d.should_replace) {
-                    return d.should_replace();
+                if (init) {
+                    var value_length = init.optimize(compressor).print_to_string().length;
+                    var fn;
+                    if (has_symbol_ref(fixed)) {
+                        fn = function() {
+                            var result = init.optimize(compressor);
+                            return result === init ? result.clone(true) : result;
+                        };
+                    } else {
+                        value_length = Math.min(value_length, fixed.print_to_string().length);
+                        fn = function() {
+                            var result = best_of_expression(init.optimize(compressor), fixed);
+                            return result === init || result === fixed ? result.clone(true) : result;
+                        };
+                    }
+                    var name_length = d.name.length;
+                    var overhead = 0;
+                    if (compressor.option("unused") && !compressor.exposed(d)) {
+                        overhead = (name_length + 2 + value_length) / d.references.length;
+                    }
+                    d.should_replace = value_length <= name_length + overhead ? fn : false;
+                } else {
+                    d.should_replace = false;
                 }
             }
+            if (d.should_replace) {
+                return d.should_replace();
+            }
         }
         return self;
 
@@ -4827,11 +4907,11 @@ merge(Compressor.prototype, {
             }
         }
         if (is_lhs(self, compressor.parent())) return self;
-        if (compressor.option("properties") && key !== prop) {
-            var node = self.flatten_object(property, compressor);
-            if (node) {
-                expr = self.expression = node.expression;
-                prop = self.property = node.property;
+        if (key !== prop) {
+            var sub = self.flatten_object(property, compressor);
+            if (sub) {
+                expr = self.expression = sub.expression;
+                prop = self.property = sub.property;
             }
         }
         if (compressor.option("properties") && compressor.option("side_effects")
@@ -4877,7 +4957,8 @@ merge(Compressor.prototype, {
         return self;
     });
 
-    AST_Lambda.DEFMETHOD("contains_this", function() {
+    AST_Lambda.DEFMETHOD("contains_this", function(grandparent) {
+        if (grandparent instanceof AST_New) return false;
         var result;
         var self = this;
         self.walk(new TreeWalker(function(node) {
@@ -4889,6 +4970,7 @@ merge(Compressor.prototype, {
     });
 
     AST_PropAccess.DEFMETHOD("flatten_object", function(key, compressor) {
+        if (!compressor.option("properties")) return;
         var arrows = compressor.option("unsafe_arrows") && compressor.option("ecma") >= 6;
         var expr = this.expression;
         if (expr instanceof AST_Object) {
@@ -4902,7 +4984,7 @@ merge(Compressor.prototype, {
                     })) break;
                     var value = prop.value;
                     if ((value instanceof AST_Accessor || value instanceof AST_Function)
-                        && value.contains_this()) break;
+                        && value.contains_this(compressor.parent())) break;
                     return make_node(AST_Sub, this, {
                         expression: make_node(AST_Array, expr, {
                             elements: props.map(function(prop) {
@@ -4952,10 +5034,8 @@ merge(Compressor.prototype, {
             }
         }
         if (is_lhs(self, compressor.parent())) return self;
-        if (compressor.option("properties")) {
-            var node = self.flatten_object(self.property, compressor);
-            if (node) return node.optimize(compressor);
-        }
+        var sub = self.flatten_object(self.property, compressor);
+        if (sub) return sub.optimize(compressor);
         var ev = self.evaluate(compressor);
         if (ev !== self) {
             ev = make_node_from_constant(ev, self).optimize(compressor);

lib/minify.js

@@ -141,11 +141,9 @@ function minify(files, options) {
         if (options.wrap) {
             toplevel = toplevel.wrap_commonjs(options.wrap);
         }
-        if (timings) timings.scope1 = Date.now();
-        if (options.compress) toplevel.figure_out_scope(options.mangle);
         if (timings) timings.compress = Date.now();
         if (options.compress) toplevel = new Compressor(options.compress).compress(toplevel);
-        if (timings) timings.scope2 = Date.now();
+        if (timings) timings.scope = Date.now();
         if (options.mangle) toplevel.figure_out_scope(options.mangle);
         if (timings) timings.mangle = Date.now();
         if (options.mangle) {
@@ -203,9 +201,9 @@ function minify(files, options) {
         if (timings) {
             timings.end = Date.now();
             result.timings = {
-                parse: 1e-3 * (timings.scope1 - timings.parse),
-                scope: 1e-3 * (timings.compress - timings.scope1 + timings.mangle - timings.scope2),
-                compress: 1e-3 * (timings.scope2 - timings.compress),
+                parse: 1e-3 * (timings.compress - timings.parse),
+                compress: 1e-3 * (timings.scope - timings.compress),
+                scope: 1e-3 * (timings.mangle - timings.scope),
                 mangle: 1e-3 * (timings.properties - timings.mangle),
                 properties: 1e-3 * (timings.output - timings.properties),
                 output: 1e-3 * (timings.end - timings.output),

lib/output.js

@@ -1361,6 +1361,7 @@ function OutputStream(options) {
             self.exported_value.print(output);
         } else if (self.exported_definition) {
             self.exported_definition.print(output);
+            if (self.exported_definition instanceof AST_Definitions) return;
         }
         if (self.module_name) {
             output.space();

package.json

@@ -4,7 +4,7 @@
   "homepage": "https://github.com/mishoo/UglifyJS2/tree/harmony",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.1.6",
+  "version": "3.1.9",
   "engines": {
     "node": ">=0.8.0"
   },

test/compress/arrays.js

@@ -204,6 +204,7 @@ constant_join_3: {
 for_loop: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unsafe: true,
         unused: true,
@@ -260,6 +261,7 @@ for_loop: {
 index: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unsafe: true,
@@ -278,6 +280,7 @@ index: {
 length: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unsafe: true,
@@ -296,6 +299,7 @@ length: {
 index_length: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unsafe: true,

test/compress/arrow.js

@@ -288,6 +288,7 @@ issue_2105_1: {
         ecma: 6,
         inline: true,
         passes: 3,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unsafe_methods: true,
@@ -314,17 +315,12 @@ issue_2105_1: {
         });
     }
     expect: {
-        (() => {
-            var quux = () => {
+        ({
+            prop() {
+                console.log;
                 console.log("PASS");
-            };
-            return {
-                prop() {
-                    console.log;
-                    quux();
-                }
-            };
-        })().prop();
+            }
+        }).prop();
     }
     expect_stdout: "PASS"
     node_version: ">=4"
@@ -335,6 +331,7 @@ issue_2105_2: {
         collapse_vars: true,
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -360,17 +357,12 @@ issue_2105_2: {
         });
     }
     expect: {
-        (() => {
-            var quux = () => {
+        ({
+            prop: () => {
+                console.log;
                 console.log("PASS");
-            };
-            return {
-                prop: () => {
-                    console.log;
-                    quux();
-                }
-            };
-        })().prop();
+            }
+        }).prop();
     }
     expect_stdout: "PASS"
     node_version: ">=6"
@@ -411,6 +403,7 @@ issue_2136_3: {
         evaluate: true,
         inline: true,
         passes: 3,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -438,6 +431,7 @@ call_args: {
         ecma: 6,
         evaluate: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
     }
     input: {
@@ -462,6 +456,7 @@ call_args_drop_param: {
         evaluate: true,
         inline: true,
         keep_fargs: false,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -509,6 +504,7 @@ issue_2084: {
         evaluate: true,
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         side_effects: true,

test/compress/async.js

@@ -141,6 +141,7 @@ async_inline: {
         evaluate: true,
         inline: true,
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,

test/compress/collapse_vars.js

@@ -2,7 +2,8 @@ collapse_vars_side_effects_1: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         function f1() {
@@ -150,7 +151,8 @@ collapse_vars_issue_721: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         define(["require", "exports", 'handlebars'], function (require, exports, hb) {
@@ -216,7 +218,8 @@ collapse_vars_properties: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         function f1(obj) {
@@ -243,7 +246,8 @@ collapse_vars_if: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         function f1() {
@@ -293,7 +297,8 @@ collapse_vars_while: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:false, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         function f1(y) {
@@ -712,7 +717,8 @@ collapse_vars_misc1: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         function f0(o, a, h) {
@@ -789,7 +795,8 @@ collapse_vars_repeated: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         function f1() {
@@ -831,7 +838,8 @@ collapse_vars_closures: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         function constant_vars_can_be_replaced_in_any_scope() {
@@ -921,7 +929,8 @@ collapse_vars_try: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         function f1() {
@@ -1118,7 +1127,8 @@ collapse_vars_constants: {
     options = {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
-        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true, reduce_vars:true
+        keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
+        reduce_funcs: true, reduce_vars:true
     }
     input: {
         function f1(x) {
@@ -1156,7 +1166,7 @@ collapse_vars_arguments: {
         collapse_vars:true, sequences:true, properties:true, dead_code:true, conditionals:true,
         comparisons:true, evaluate:true, booleans:true, loops:true, unused:true, hoist_funs:true,
         keep_fargs:true, if_return:true, join_vars:true, cascade:true, side_effects:true,
-        toplevel:true, reduce_vars:true
+        toplevel:true, reduce_funcs: true, reduce_vars:true
     }
     input: {
         var outer = function() {
@@ -1280,6 +1290,7 @@ collapse_vars_regexp: {
         hoist_funs:    true,
         keep_fargs:    true,
         loops:         false,
+        reduce_funcs:  true,
         reduce_vars:   true,
         side_effects:  true,
         unused:        true,
@@ -1454,6 +1465,7 @@ issue_1562: {
     options = {
         collapse_vars: true,
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -1487,6 +1499,7 @@ issue_1605_1: {
     options = {
         collapse_vars: true,
         toplevel: false,
+        unused: true,
     }
     input: {
         function foo(x) {
@@ -1509,6 +1522,7 @@ issue_1605_2: {
     options = {
         collapse_vars: true,
         toplevel: "vars",
+        unused: true,
     }
     input: {
         function foo(x) {
@@ -1636,6 +1650,7 @@ issue_1631_3: {
 var_side_effects_1: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     input: {
         var print = console.log.bind(console);
@@ -1658,6 +1673,7 @@ var_side_effects_1: {
 var_side_effects_2: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     input: {
         var print = console.log.bind(console);
@@ -1683,6 +1699,7 @@ var_side_effects_3: {
         collapse_vars: true,
         pure_getters: true,
         unsafe: true,
+        unused: true,
     }
     input: {
         var print = console.log.bind(console);
@@ -1705,6 +1722,7 @@ var_side_effects_3: {
 reduce_vars_assign: {
     options = {
         collapse_vars: true,
+        reduce_funcs: true,
         reduce_vars: true,
     }
     input: {
@@ -1727,6 +1745,7 @@ reduce_vars_assign: {
 iife_1: {
     options = {
         collapse_vars: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -1747,6 +1766,7 @@ iife_1: {
 iife_2: {
     options = {
         collapse_vars: true,
+        reduce_funcs: false,
         reduce_vars: false,
         toplevel: true,
         unused: false,
@@ -1758,6 +1778,7 @@ iife_2: {
         }(foo);
     }
     expect: {
+        var foo;
         !function(x) {
             console.log(x);
         }(bar());
@@ -2044,6 +2065,7 @@ ref_scope: {
 chained_1: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     input: {
         var a = 2;
@@ -2060,6 +2082,7 @@ chained_1: {
 chained_2: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     input: {
         var a;
@@ -2160,6 +2183,7 @@ inner_lvalues: {
 double_def: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     input: {
         var a = x, a = a && y;
@@ -2174,6 +2198,7 @@ double_def: {
 toplevel_single_reference: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     input: {
         var a;
@@ -2183,9 +2208,10 @@ toplevel_single_reference: {
         }
     }
     expect: {
-        var a;
-        for (var b in x)
+        for (var b in x) {
+            var a;
             b(a = b);
+        }
     }
 }
 
@@ -2193,6 +2219,7 @@ unused_orig: {
     options = {
         collapse_vars: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2215,10 +2242,11 @@ unused_orig: {
     expect: {
         var a = 1;
         console.log(function(b) {
-            var a;
             var c = b;
-            for (var d in c)
+            for (var d in c) {
+                var a;
                 return --b + (a = c[0]);
+            }
             a && a.NaN;
         }([2]), a);
     }
@@ -2230,6 +2258,7 @@ issue_315: {
         collapse_vars: true,
         evaluate: true,
         keep_fargs: false,
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         unused: true,
@@ -2565,7 +2594,10 @@ issue_2250_1: {
     options = {
         collapse_vars: true,
         conditionals: true,
+        passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
+        unused: true,
     }
     input: {
         function f(x) {
@@ -2604,9 +2636,11 @@ issue_2250_2: {
     options = {
         collapse_vars: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
+        unused: true,
     }
     input: {
         {
@@ -2632,6 +2666,7 @@ issue_2250_2: {
 issue_2298: {
     options = {
         collapse_vars: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -2997,6 +3032,7 @@ issue_2364_5: {
         evaluate: true,
         pure_getters: true,
         properties: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -3163,6 +3199,7 @@ pure_getters_chain: {
     options = {
         collapse_vars: true,
         pure_getters: true,
+        unused: true,
     }
     input: {
         function o(t, r) {
@@ -3183,6 +3220,7 @@ pure_getters_chain: {
 conditional_1: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     input: {
         function f(a, b) {
@@ -3207,6 +3245,7 @@ conditional_1: {
 conditional_2: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     input: {
         function f(a, b) {
@@ -3223,3 +3262,141 @@ conditional_2: {
     }
     expect_stdout: "5 5"
 }
+
+issue_2425_1: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = 8;
+        (function(b) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect: {
+        var a = 8;
+        (function(b) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect_stdout: "15"
+}
+
+issue_2425_2: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = 8;
+        (function(b, c) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect: {
+        var a = 8;
+        (function(b, c) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect_stdout: "15"
+}
+
+issue_2425_3: {
+    options = {
+        collapse_vars: true,
+        unused: true,
+    }
+    input: {
+        var a = 8;
+        (function(b, b) {
+            b.toString();
+        })(--a, a |= 10);
+        console.log(a);
+    }
+    expect: {
+        var a = 8;
+        (function(b, b) {
+            (a |= 10).toString();
+        })(--a);
+        console.log(a);
+    }
+    expect_stdout: "15"
+}
+
+issue_2437: {
+    options = {
+        collapse_vars: true,
+        conditionals: true,
+        inline: true,
+        join_vars: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        side_effects: true,
+        sequences: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function foo() {
+            bar();
+        }
+        function bar() {
+            if (xhrDesc) {
+                var req = new XMLHttpRequest();
+                var result = !!req.onreadystatechange;
+                Object.defineProperty(XMLHttpRequest.prototype, 'onreadystatechange', xhrDesc || {});
+                return result;
+            }
+            else {
+                var req = new XMLHttpRequest();
+                var detectFunc = function () { };
+                req.onreadystatechange = detectFunc;
+                var result = req[SYMBOL_FAKE_ONREADYSTATECHANGE_1] === detectFunc;
+                req.onreadystatechange = null;
+                return result;
+            }
+        }
+        foo();
+    }
+    expect: {
+        !function() {
+            if (xhrDesc)
+                return result = !!(req = new XMLHttpRequest()).onreadystatechange,
+                    Object.defineProperty(XMLHttpRequest.prototype, "onreadystatechange", xhrDesc || {}),
+                    result;
+            var req = new XMLHttpRequest(), detectFunc = function() {};
+            req.onreadystatechange = detectFunc;
+            var result = req[SYMBOL_FAKE_ONREADYSTATECHANGE_1] === detectFunc;
+            req.onreadystatechange = null;
+        }();
+    }
+}
+
+issue_2453: {
+    options = {
+        collapse_vars: true,
+        toplevel: true,
+    }
+    input: {
+        function log(n) {
+            console.log(n);
+        }
+        const a = 42;
+        log(a);
+    }
+    expect: {
+        function log(n) {
+            console.log(n);
+        }
+        const a = 42;
+        log(a);
+    }
+    expect_stdout: "42"
+}

test/compress/comparing.js

@@ -96,6 +96,7 @@ self_comparison_1: {
 self_comparison_2: {
     options = {
         comparisons: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
     }

test/compress/const.js

@@ -12,6 +12,7 @@ issue_1191: {
         join_vars     : true,
         sequences     : false,
         collapse_vars : false,
+        reduce_funcs  : true,
         reduce_vars   : true,
     }
     input: {
@@ -44,6 +45,7 @@ issue_1194: {
         join_vars     : true,
         sequences     : false,
         collapse_vars : false,
+        reduce_funcs  : true,
         reduce_vars   : true,
     }
     input: {
@@ -72,6 +74,7 @@ issue_1396: {
         join_vars     : true,
         sequences     : false,
         collapse_vars : false,
+        reduce_funcs  : true,
         reduce_vars   : true,
     }
     input: {
@@ -143,6 +146,7 @@ regexp_literal_not_const: {
         join_vars     : true,
         sequences     : false,
         collapse_vars : false,
+        reduce_funcs  : true,
         reduce_vars   : true,
     }
     input: {

test/compress/dead-code.js

@@ -202,6 +202,7 @@ dead_code_const_declaration: {
         booleans     : true,
         conditionals : true,
         evaluate     : true,
+        reduce_funcs : true,
         reduce_vars  : true,
     };
     input: {
@@ -229,6 +230,7 @@ dead_code_const_annotation: {
         booleans     : true,
         conditionals : true,
         evaluate     : true,
+        reduce_funcs : true,
         reduce_vars  : true,
         toplevel     : true,
     };
@@ -281,6 +283,7 @@ dead_code_const_annotation_complex_scope: {
         booleans     : true,
         conditionals : true,
         evaluate     : true,
+        reduce_funcs : true,
         reduce_vars  : true,
         toplevel     : true,
     };
@@ -439,6 +442,7 @@ global_timeout_and_interval_symbols: {
 issue_2233_2: {
     options = {
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unsafe: true,
@@ -470,6 +474,7 @@ issue_2233_2: {
 issue_2233_3: {
     options = {
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,

test/compress/destructuring.js

@@ -262,6 +262,7 @@ destructuring_dont_evaluate_with_undefined_as_default_assignment: {
 
 reduce_vars: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
     }
     input: {

test/compress/drop-unused.js

@@ -733,6 +733,7 @@ drop_value: {
 const_assign: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -785,6 +786,7 @@ issue_1539: {
 vardef_value: {
     options = {
         keep_fnames: false,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -846,6 +848,7 @@ assign_chain: {
 issue_1583: {
     options = {
         keep_fargs: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1200,6 +1203,7 @@ var_catch_toplevel: {
     options = {
         conditionals: true,
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -1294,11 +1298,12 @@ issue_2063: {
     }
 }
 
-issue_2105: {
+issue_2105_1: {
     options = {
         collapse_vars: true,
         inline: true,
         passes: 3,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -1324,17 +1329,51 @@ issue_2105: {
         });
     }
     expect: {
-        (function() {
-            var quux = function() {
+        ({
+            prop: function() {
+                console.log;
                 console.log("PASS");
-            };
-            return {
-                prop: function() {
-                    console.log;
-                    quux();
+            }
+        }).prop();
+    }
+    expect_stdout: "PASS"
+}
+
+issue_2105_2: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        passes: 3,
+        properties: true,
+        pure_getters: "strict",
+        reduce_funcs: true,
+        reduce_vars: true,
+        side_effects: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        !function(factory) {
+            factory();
+        }( function() {
+            return function(fn) {
+                fn()().prop();
+            }( function() {
+                function bar() {
+                    var quux = function() {
+                        console.log("PASS");
+                    }, foo = function() {
+                        console.log;
+                        quux();
+                    };
+                    return { prop: foo };
                 }
-            };
-        })().prop();
+                return bar;
+            } );
+        });
+    }
+    expect: {
+        console.log("PASS");
     }
     expect_stdout: "PASS"
 }
@@ -1389,6 +1428,7 @@ issue_2136_3: {
         evaluate: true,
         inline: true,
         passes: 3,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,

test/compress/evaluate.js

@@ -345,6 +345,7 @@ unsafe_constant: {
 unsafe_object: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unsafe: true,
@@ -373,6 +374,7 @@ unsafe_object: {
 unsafe_object_nested: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unsafe: true,
@@ -401,6 +403,7 @@ unsafe_object_nested: {
 unsafe_object_complex: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unsafe: true,
@@ -429,6 +432,7 @@ unsafe_object_complex: {
 unsafe_object_repeated: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unsafe: true,
@@ -457,6 +461,7 @@ unsafe_object_repeated: {
 unsafe_object_accessor: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unsafe: true,
     }
@@ -757,6 +762,7 @@ call_args: {
     options = {
         evaluate: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
     }
     input: {
@@ -779,6 +785,7 @@ call_args_drop_param: {
         evaluate: true,
         inline: true,
         keep_fargs: false,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -1109,6 +1116,7 @@ Infinity_NaN_undefined_LHS: {
 issue_1964_1: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unsafe_regexp: false,
         unused: true,
@@ -1138,6 +1146,7 @@ issue_1964_1: {
 issue_1964_2: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unsafe_regexp: true,
         unused: true,
@@ -1294,6 +1303,7 @@ issue_2231_2: {
 self_comparison_1: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unsafe: true,
@@ -1314,6 +1324,7 @@ self_comparison_2: {
         evaluate: true,
         hoist_props: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,

test/compress/export.js

@@ -124,6 +124,7 @@ async_func: {
 issue_2134_1: {
     options = {
         keep_fargs: false,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -141,6 +142,7 @@ issue_2134_1: {
 issue_2134_2: {
     options = {
         keep_fargs: false,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -250,3 +252,13 @@ dynamic_import: {
         r.foo();
     }
 }
+
+trailing_comma: {
+    beautify = {
+        beautify: true,
+    }
+    input: {
+        export const a = 1;
+    }
+    expect_exact: "export const a = 1;"
+}

test/compress/functions.js

@@ -19,6 +19,7 @@ iifes_returning_constants_keep_fargs_true: {
         booleans      : true,
         if_return     : true,
         join_vars     : true,
+        reduce_funcs  : true,
         reduce_vars   : true,
         cascade       : true,
         inline        : true,
@@ -55,6 +56,7 @@ iifes_returning_constants_keep_fargs_false: {
         booleans      : true,
         if_return     : true,
         join_vars     : true,
+        reduce_funcs  : true,
         reduce_vars   : true,
         cascade       : true,
         inline        : true,
@@ -101,6 +103,7 @@ issue_1841_1: {
     options = {
         keep_fargs: false,
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -127,6 +130,7 @@ issue_1841_2: {
     options = {
         keep_fargs: false,
         pure_getters: false,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -154,6 +158,7 @@ function_returning_constant_literal: {
         inline: true,
         passes: 2,
         properties: true,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -305,6 +310,7 @@ issue_2084: {
         evaluate: true,
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         side_effects: true,
@@ -340,6 +346,7 @@ issue_2084: {
 issue_2097: {
     options = {
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -508,3 +515,42 @@ issue_2114_2: {
     }
     expect_stdout: "2"
 }
+
+issue_2428: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        passes: 3,
+        pure_getters: "strict",
+        reduce_funcs: true,
+        reduce_vars: true,
+        side_effects: true,
+        toplevel: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        function bar(k) {
+            console.log(k);
+        }
+        function foo(x) {
+            return bar(x);
+        }
+        function baz(a) {
+            foo(a);
+        }
+        baz(42);
+        baz("PASS");
+    }
+    expect: {
+        function baz(a) {
+            console.log(a);
+        }
+        baz(42);
+        baz("PASS");
+    }
+    expect_stdout: [
+        "42",
+        "PASS",
+    ]
+}

test/compress/harmony.js

@@ -736,6 +736,7 @@ object_spread_unsafe: {
         evaluate: true,
         join_vars: true,
         passes: 3,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -903,6 +904,7 @@ issue_2349b: {
         inline: true,
         passes: 3,
         properties: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         side_effects: true,

test/compress/hoist_props.js

@@ -3,6 +3,7 @@ issue_2377_1: {
         evaluate: true,
         inline: true,
         hoist_props: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -35,6 +36,7 @@ issue_2377_2: {
         inline: true,
         hoist_props: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -66,6 +68,7 @@ issue_2377_3: {
         inline: true,
         hoist_props: true,
         passes: 3,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -92,6 +95,7 @@ issue_2377_3: {
 direct_access_1: {
     options = {
         hoist_props: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -120,6 +124,7 @@ direct_access_1: {
 direct_access_2: {
     options = {
         hoist_props: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -143,6 +148,7 @@ direct_access_2: {
 direct_access_3: {
     options = {
         hoist_props: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -163,6 +169,7 @@ direct_access_3: {
 single_use: {
     options = {
         hoist_props: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -187,6 +194,7 @@ single_use: {
 name_collision_1: {
     options = {
         hoist_props: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
     }
@@ -224,6 +232,7 @@ name_collision_1: {
 name_collision_2: {
     options = {
         hoist_props: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
     }
@@ -257,6 +266,7 @@ name_collision_2: {
 name_collision_3: {
     options = {
         hoist_props: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
     }
@@ -293,6 +303,7 @@ contains_this_1: {
         hoist_props: true,
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -318,6 +329,7 @@ contains_this_2: {
         hoist_props: true,
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -345,6 +357,7 @@ contains_this_3: {
         hoist_props: true,
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -369,3 +382,169 @@ contains_this_3: {
     }
     expect_stdout: "1 1 true"
 }
+
+hoist_class: {
+    options = {
+        comparisons: true,
+        evaluate: true,
+        hoist_props: true,
+        inline: true,
+        keep_fnames: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        function run(c, v) {
+            return new c(v).value;
+        }
+        var o = {
+            p: class Foo {
+                constructor(value) {
+                    this.value = value * 10;
+                }
+            },
+            x: 1,
+            y: 2,
+        };
+        console.log(o.p.name, o.p === o.p, run(o.p, o.x), run(o.p, o.y));
+    }
+    expect: {
+        function run(c, v) {
+            return new c(v).value;
+        }
+        var o_p = class Foo {
+            constructor(value) {
+                this.value = 10 * value;
+            }
+        };
+        console.log(o_p.name, true, run(o_p, 1), run(o_p, 2));
+    }
+    node_version: ">=6"
+    expect_stdout: "Foo true 10 20"
+}
+
+hoist_class_with_new: {
+    options = {
+        comparisons: true,
+        evaluate: true,
+        hoist_props: true,
+        inline: true,
+        keep_fnames: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            p: class Foo {
+                constructor(value) {
+                    this.value = value * 10;
+                }
+            },
+            x: 1,
+            y: 2,
+        };
+        console.log(o.p.name, o.p === o.p, new o.p(o.x).value, new o.p(o.y).value);
+    }
+    expect: {
+        // FIXME: class `o.p` not hoisted due to `new`
+        var o = {
+            p: class Foo {
+                constructor(value) {
+                    this.value = 10 * value;
+                }
+            },
+            x: 1,
+            y: 2
+        };
+        console.log(o.p.name, o.p == o.p, new o.p(o.x).value, new o.p(o.y).value);
+    }
+    node_version: ">=6"
+    expect_stdout: "Foo true 10 20"
+}
+
+hoist_function_with_call: {
+    options = {
+        comparisons: true,
+        evaluate: true,
+        hoist_props: true,
+        inline: true,
+        keep_fnames: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            p: function Foo(value) {
+                return 10 * value;
+            },
+            x: 1,
+            y: 2
+        };
+        console.log(o.p.name, o.p === o.p, o.p(o.x), o.p(o.y));
+    }
+    expect: {
+        var o_p = function Foo(value){
+            return 10 * value
+        };
+        console.log(o_p.name, true, o_p(1), o_p(2));
+    }
+    expect_stdout: "Foo true 10 20"
+}
+
+new_this: {
+    options = {
+        evaluate: true,
+        hoist_props: true,
+        inline: true,
+        passes: 2,
+        reduce_funcs: true,
+        reduce_vars: true,
+        toplevel: true,
+        unused: true,
+    }
+    input: {
+        var o = {
+            a: 1,
+            b: 2,
+            f: function(a) {
+                this.b = a;
+            }
+        };
+        console.log(new o.f(o.a).b, o.b);
+    }
+    expect: {
+        console.log(new function(a) {
+            this.b = a;
+        }(1).b, 2);
+    }
+    expect_stdout: "1 2"
+}
+
+issue_2462: {
+    options = {
+        hoist_props: true,
+        reduce_funcs: true,
+        reduce_vars: true,
+    }
+    input: {
+        export const Foo = {
+            a: 1,
+            b: () => 2
+        };
+    }
+    expect: {
+        export const Foo = {
+            a: 1,
+            b: () => 2
+        };
+    }
+}

test/compress/issue-1041.js

@@ -14,6 +14,7 @@ const_declaration: {
 const_pragma: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
     };
 
@@ -29,6 +30,7 @@ const_pragma: {
 not_const: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
     };
 

test/compress/issue-1609.js

@@ -2,6 +2,7 @@ chained_evaluation_1: {
     options = {
         collapse_vars: true,
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -28,6 +29,7 @@ chained_evaluation_2: {
     options = {
         collapse_vars: true,
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }

test/compress/issue-1656.js

@@ -15,6 +15,7 @@ f7: {
         negate_iife: true,
         passes: 3,
         properties: true,
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         side_effects: true,

test/compress/issue-1673.js

@@ -1,5 +1,6 @@
 side_effects_catch: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -34,6 +35,7 @@ side_effects_catch: {
 
 side_effects_else: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -62,6 +64,7 @@ side_effects_else: {
 
 side_effects_finally: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -98,6 +101,7 @@ side_effects_finally: {
 
 side_effects_label: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -130,6 +134,7 @@ side_effects_label: {
 
 side_effects_switch: {
     options = {
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,

test/compress/issue-1787.js

@@ -2,6 +2,7 @@ unary_prefix: {
     options = {
         evaluate: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }

test/compress/issue-1833.js

@@ -1,6 +1,7 @@
 iife_for: {
     options = {
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -26,6 +27,7 @@ iife_for: {
 iife_for_in: {
     options = {
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -51,6 +53,7 @@ iife_for_in: {
 iife_do: {
     options = {
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -80,6 +83,7 @@ iife_do: {
 iife_while: {
     options = {
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,

test/compress/issue-2001.js

@@ -177,6 +177,7 @@ export_mangle_2: {
 export_mangle_3: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     mangle = {
         toplevel: true,
@@ -195,6 +196,7 @@ export_mangle_3: {
 export_mangle_4: {
     options = {
         collapse_vars: true,
+        unused: true,
     }
     mangle = {
         toplevel: true,

test/compress/issue-281.js

@@ -3,6 +3,7 @@ collapse_vars_constants: {
         collapse_vars: true,
         evaluate: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -240,6 +241,7 @@ negate_iife_issue_1073: {
         evaluate: true,
         inline: true,
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         unused: true,
@@ -267,6 +269,7 @@ issue_1288_side_effects: {
         evaluate: true,
         inline: true,
         negate_iife: true,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -299,6 +302,7 @@ inner_var_for_in_1: {
     options = {
         evaluate: true,
         inline: true,
+        reduce_funcs: true,
         reduce_vars: true,
     }
     input: {
@@ -330,6 +334,7 @@ issue_1595_3: {
         evaluate: true,
         inline: true,
         passes: 2,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }

test/compress/issue-973.js

@@ -51,6 +51,7 @@ this_binding_collapse_vars: {
     options = {
         collapse_vars: true,
         toplevel: true,
+        unused: true,
     };
     input: {
         var c = a; c();

test/compress/properties.js

@@ -940,6 +940,7 @@ methods_keep_quoted_from_dead_code: {
         dead_code: true,
         ecma: 6,
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unsafe_methods: true,
@@ -1085,6 +1086,7 @@ lhs_prop_2: {
         evaluate: true,
         inline: true,
         properties: true,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         unused: true,
@@ -1131,6 +1133,7 @@ prop_side_effects_1: {
         evaluate: true,
         inline: true,
         properties: true,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -1167,6 +1170,7 @@ prop_side_effects_2: {
         inline: true,
         passes: 2,
         properties: true,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -1282,3 +1286,22 @@ computed_property: {
     ]
     node_version: ">=4"
 }
+
+new_this: {
+    options = {
+        properties: true,
+        side_effects: true,
+    }
+    input: {
+        new {
+            f: function(a) {
+                this.a = a;
+            }
+        }.f(42);
+    }
+    expect: {
+        new function(a) {
+            this.a = a;
+        }(42);
+    }
+}

test/compress/pure_getters.js

@@ -1,6 +1,7 @@
 strict: {
     options = {
         pure_getters: "strict",
+        reduce_funcs: false,
         reduce_vars: false,
         side_effects: true,
         toplevel: true,
@@ -30,6 +31,7 @@ strict: {
 strict_reduce_vars: {
     options = {
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -58,6 +60,7 @@ strict_reduce_vars: {
 unsafe: {
     options = {
         pure_getters: true,
+        reduce_funcs: false,
         reduce_vars: false,
         side_effects: true,
         toplevel: true,
@@ -84,6 +87,7 @@ unsafe: {
 unsafe_reduce_vars: {
     options = {
         pure_getters: true,
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -185,6 +189,7 @@ issue_2110_1: {
         pure_getters: "strict",
         sequences: true,
         side_effects: true,
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -215,6 +220,7 @@ issue_2110_2: {
     options = {
         collapse_vars: true,
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -247,6 +253,7 @@ set_immutable_1: {
         collapse_vars: true,
         evaluate: true,
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -270,6 +277,7 @@ set_immutable_2: {
         cascade: true,
         conditionals: true,
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         side_effects: true,
@@ -293,6 +301,7 @@ set_immutable_3: {
         collapse_vars: true,
         evaluate: true,
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -318,6 +327,7 @@ set_immutable_4: {
         cascade: true,
         conditionals: true,
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         side_effects: true,
@@ -343,6 +353,7 @@ set_mutable_1: {
         collapse_vars: true,
         evaluate: true,
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         unused: true,
     }
@@ -367,6 +378,7 @@ set_mutable_2: {
         cascade: true,
         conditionals: true,
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         side_effects: true,
@@ -403,6 +415,7 @@ issue_2265_1: {
 issue_2265_2: {
     options = {
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -428,6 +441,7 @@ issue_2265_2: {
 issue_2265_3: {
     options = {
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,
@@ -447,6 +461,7 @@ issue_2265_3: {
 issue_2265_4: {
     options = {
         pure_getters: "strict",
+        reduce_funcs: true,
         reduce_vars: true,
         side_effects: true,
         toplevel: true,

test/compress/screw-ie8.js

@@ -187,6 +187,7 @@ dont_screw_try_catch_undefined: {
 reduce_vars: {
     options = {
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         ie8: true,
         unused: true,

test/compress/switch.js

@@ -714,6 +714,7 @@ issue_1705_2: {
     options = {
         dead_code: true,
         evaluate: true,
+        reduce_funcs: true,
         reduce_vars: true,
         sequences: true,
         side_effects: true,

test/mocha/minify.js

@@ -328,4 +328,36 @@ describe("minify", function() {
             });
         });
     });
+
+    describe("collapse_vars", function() {
+        it("Should not produce invalid AST", function() {
+            var code = [
+                "function f(a) {",
+                "    a = x();",
+                "    return a;",
+                "}",
+                "f();",
+            ].join("\n");
+            var ast = Uglify.minify(code, {
+                compress: false,
+                mangle: false,
+                output: {
+                    ast: true
+                },
+            }).ast;
+            assert.strictEqual(ast.TYPE, "Toplevel");
+            assert.strictEqual(ast.body.length, 2);
+            assert.strictEqual(ast.body[0].TYPE, "Defun");
+            assert.strictEqual(ast.body[0].body.length, 2);
+            assert.strictEqual(ast.body[0].body[0].TYPE, "SimpleStatement");
+            var stat = ast.body[0].body[0];
+            Uglify.minify(ast, {
+                compress: {
+                    sequences: false
+                }
+            });
+            assert.ok(stat.body);
+            assert.strictEqual(stat.print_to_string(), "a=x()");
+        });
+    });
 });

test/ufuzz.js

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