v3.5.6

fixes #3371

lib/compress.js

@@ -114,7 +114,7 @@ function Compressor(options, false_by_default) {
         };
     } else if (Array.isArray(pure_funcs)) {
         this.pure_funcs = function(node) {
-            return pure_funcs.indexOf(node.expression.print_to_string()) < 0;
+            return !member(node.expression.print_to_string(), pure_funcs);
         };
     } else {
         this.pure_funcs = return_true;
@@ -131,7 +131,7 @@ function Compressor(options, false_by_default) {
             top_retain = top_retain.split(/,/);
         }
         this.top_retain = function(def) {
-            return top_retain.indexOf(def.name) >= 0;
+            return member(def.name, top_retain);
         };
     }
     var toplevel = this.options["toplevel"];
@@ -312,8 +312,22 @@ merge(Compressor.prototype, {
         return value instanceof AST_SymbolRef && value.fixed_value() || value;
     }
 
+    function is_read_only_fn(value, name) {
+        if (value instanceof AST_Boolean) return native_fns.Boolean[name];
+        if (value instanceof AST_Number) return native_fns.Number[name];
+        if (value instanceof AST_String) return native_fns.String[name];
+        if (name == "valueOf") return false;
+        if (value instanceof AST_Array) return native_fns.Array[name];
+        if (value instanceof AST_Function) return native_fns.Function[name];
+        if (value instanceof AST_Object) return native_fns.Object[name];
+        if (value instanceof AST_RegExp) return native_fns.RegExp[name];
+    }
+
     function is_modified(compressor, tw, node, value, level, immutable) {
         var parent = tw.parent(level);
+        if (compressor.option("unsafe") && parent instanceof AST_Dot && is_read_only_fn(value, parent.property)) {
+            return;
+        }
         var lhs = is_lhs(node, parent);
         if (lhs) return lhs;
         if (!immutable
@@ -344,7 +358,7 @@ merge(Compressor.prototype, {
             def.assignments = 0;
             def.chained = false;
             def.direct_access = false;
-            def.escaped = false;
+            def.escaped = [];
             def.fixed = !def.scope.pinned()
                 && !compressor.exposed(def)
                 && !(def.init instanceof AST_Function && def.init !== def.scope)
@@ -483,8 +497,9 @@ merge(Compressor.prototype, {
                 || parent instanceof AST_Call && (node !== parent.expression || parent instanceof AST_New)
                 || parent instanceof AST_Exit && node === parent.value && node.scope !== d.scope
                 || parent instanceof AST_VarDef && node === parent.value) {
+                d.escaped.push(parent);
                 if (depth > 1 && !(value && value.is_constant_expression(scope))) depth = 1;
-                if (!d.escaped || d.escaped > depth) d.escaped = depth;
+                if (!d.escaped.depth || d.escaped.depth > depth) d.escaped.depth = depth;
                 return;
             } else if (parent instanceof AST_Array
                 || parent instanceof AST_Binary && lazy_op[parent.operator]
@@ -742,8 +757,8 @@ merge(Compressor.prototype, {
                         d.fixed = false;
                     }
                 }
-            }
                 mark_escaped(tw, d, this.scope, this, value, 0, 1);
+            }
             var parent;
             if (d.fixed instanceof AST_Defun
                 && !((parent = tw.parent()) instanceof AST_Call && parent.expression === this)) {
@@ -1579,9 +1594,14 @@ merge(Compressor.prototype, {
                     lvalues[candidate.name.name] = lhs;
                 }
                 var tw = new TreeWalker(function(node) {
-                    var sym = root_expr(node);
+                    var value;
-                    if (sym instanceof AST_SymbolRef || sym instanceof AST_This) {
+                    if (node instanceof AST_SymbolRef) {
-                        lvalues[sym.name] = lvalues[sym.name] || is_modified(compressor, tw, node, node, 0);
+                        value = node.fixed_value() || node;
+                    } else if (node instanceof AST_This) {
+                        value = node;
+                    }
+                    if (value && !lvalues[node.name]) {
+                        lvalues[node.name] = is_modified(compressor, tw, node, value, 0);
                     }
                 });
                 expr.walk(tw);
@@ -1691,7 +1711,7 @@ merge(Compressor.prototype, {
                     CHANGED = true;
                     statements.splice(i, 1);
                 } else if (stat instanceof AST_Directive) {
-                    if (seen_dirs.indexOf(stat.value) < 0) {
+                    if (!member(stat.value, seen_dirs)) {
                         i++;
                         seen_dirs.push(stat.value);
                     } else {
@@ -2833,7 +2853,7 @@ merge(Compressor.prototype, {
             var fixed = this.fixed_value();
             if (!fixed) return this;
             var value;
-            if (cached.indexOf(fixed) >= 0) {
+            if (member(fixed, cached)) {
                 value = fixed._eval();
             } else {
                 this._eval = return_this;
@@ -2847,9 +2867,25 @@ merge(Compressor.prototype, {
             }
             if (value && typeof value == "object") {
                 var escaped = this.definition().escaped;
-                if (escaped && depth > escaped) return this;
+                switch (escaped.length) {
+                  case 0:
+                    break;
+                  case 1:
+                    if (contains_ref(escaped[0], this)) break;
+                  default:
+                    if (depth > escaped.depth) return this;
+                }
             }
             return value;
+
+            function contains_ref(expr, ref) {
+                var found = false;
+                expr.walk(new TreeWalker(function(node) {
+                    if (found) return true;
+                    if (node === ref) return found = true;
+                }));
+                return found;
+            }
         });
         var global_objs = {
             Array: Array,
@@ -3596,13 +3632,22 @@ merge(Compressor.prototype, {
                         } else if (compressor.option("functions")
                             && def.value === def.name.fixed_value()
                             && def.value instanceof AST_Function
-                            && !def.value.name
+                            && can_rename(def.value, def.name.name)
-                            && !def.value.variables.get(def.name.name)
                             && (!compressor.has_directive("use strict") || parent instanceof AST_Scope)) {
                             compressor.warn("Declaring {name} as function [{file}:{line},{col}]", template(def.name));
                             var defun = make_node(AST_Defun, def, def.value);
                             defun.name = make_node(AST_SymbolDefun, def.name, def.name);
-                            def.name.scope.resolve().def_function(defun.name);
+                            var name_def = def.name.scope.resolve().def_function(defun.name);
+                            if (def.value.name) {
+                                var old_def = def.value.name.definition();
+                                def.value.walk(new TreeWalker(function(node) {
+                                    if (node instanceof AST_SymbolRef && node.definition() === old_def) {
+                                        node.name = name_def.name;
+                                        node.thedef = name_def;
+                                        node.reference({});
+                                    }
+                                }));
+                            }
                             body.push(defun);
                         } else {
                             if (side_effects.length > 0) {
@@ -3633,6 +3678,11 @@ merge(Compressor.prototype, {
                         }
                         sym.eliminated++;
                     }
+
+                    function can_rename(fn, name) {
+                        var def = fn.variables.get(name);
+                        return !def || fn.name && def === fn.name.definition();
+                    }
                 });
                 if (head.length > 0 || tail.length > 0) {
                     node.definitions = head.concat(tail);
@@ -3658,6 +3708,7 @@ merge(Compressor.prototype, {
             //    https://github.com/mishoo/UglifyJS2/issues/44
             //    https://github.com/mishoo/UglifyJS2/issues/1830
             //    https://github.com/mishoo/UglifyJS2/issues/1838
+            //    https://github.com/mishoo/UglifyJS2/issues/3371
             // that's an invalid AST.
             // We fix it at this stage by moving the `var` outside the `for`.
             if (node instanceof AST_For) {
@@ -3668,7 +3719,15 @@ merge(Compressor.prototype, {
                     node.init = block.body.pop();
                     block.body.push(node);
                 }
-                if (node.init instanceof AST_SimpleStatement) {
+                if (node.init instanceof AST_Defun) {
+                    if (!block) {
+                        block = make_node(AST_BlockStatement, node, {
+                            body: [ node ]
+                        });
+                    }
+                    block.body.splice(-1, 0, node.init);
+                    node.init = null;
+                } else if (node.init instanceof AST_SimpleStatement) {
                     node.init = node.init.body;
                 } else if (is_empty(node.init)) {
                     node.init = null;
@@ -3974,7 +4033,7 @@ merge(Compressor.prototype, {
                 var def = sym.definition();
                 if (def.assignments != count) return;
                 if (def.direct_access) return;
-                if (def.escaped == 1) return;
+                if (def.escaped.depth == 1) return;
                 if (def.references.length == count) return;
                 if (def.single_use) return;
                 if (top_retain(def)) return;
@@ -5854,7 +5913,7 @@ merge(Compressor.prototype, {
             var single_use = def.single_use && !(parent instanceof AST_Call && parent.is_expr_pure(compressor));
             if (single_use && fixed instanceof AST_Lambda) {
                 if (def.scope !== self.scope
-                    && (!compressor.option("reduce_funcs") || def.escaped == 1 || fixed.inlined)) {
+                    && (!compressor.option("reduce_funcs") || def.escaped.depth == 1 || fixed.inlined)) {
                     single_use = false;
                 } else if (recursive_ref(compressor, def)) {
                     single_use = false;

package.json

@@ -3,7 +3,7 @@
   "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.5.5",
+  "version": "3.5.6",
   "engines": {
     "node": ">=0.8.0"
   },

test/compress/evaluate.js

@@ -1687,3 +1687,28 @@ try_increment: {
     }
     expect_stdout: "1"
 }
+
+unsafe_escaped: {
+    options = {
+        evaluate: true,
+        inline: true,
+        passes: 3,
+        reduce_vars: true,
+        side_effects: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        (function(a) {
+            console.log(function(index) {
+                return a[index];
+            }(function(term) {
+                return a.indexOf(term);
+            }("PASS")));
+        })([ "PASS" ]);
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}

test/compress/functions.js

@@ -2712,8 +2712,8 @@ functions: {
     }
     input: {
         !function() {
-            var a = function() {
+            var a = function a() {
-                return "a";
+                return a && "a";
             };
             var b = function x() {
                 return !!x;
@@ -2736,19 +2736,19 @@ functions: {
     expect: {
         !function() {
             function a() {
-                return "a";
+                return a && "a";
+            }
+            function b() {
+                return !!b;
             }
-            var b = function x() {
-                return !!x;
-            };
             var c = function(c) {
                 return c;
             };
             if (c(b(a()))) {
                 function d() {}
-                var e = function y() {
+                function e() {
-                    return typeof y;
+                    return typeof e;
-                };
+                }
                 var f = function(f) {
                     return f;
                 };
@@ -2768,8 +2768,8 @@ functions_use_strict: {
     input: {
         "use strict";
         !function() {
-            var a = function() {
+            var a = function a() {
-                return "a";
+                return a && "a";
             };
             var b = function x() {
                 return !!x;
@@ -2793,11 +2793,11 @@ functions_use_strict: {
         "use strict";
         !function() {
             function a() {
-                return "a";
+                return a && "a";
+            }
+            function b() {
+                return !!b;
             }
-            var b = function x() {
-                return !!x;
-            };
             var c = function(c) {
                 return c;
             };
@@ -3012,3 +3012,32 @@ issue_3366: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3371: {
+    options = {
+        functions: true,
+        inline: true,
+        reduce_vars: true,
+        side_effects: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a = function f() {
+                (function() {
+                    console.log(typeof f);
+                })();
+            };
+            while (a());
+        })();
+    }
+    expect: {
+        (function() {
+            function a() {
+                console.log(typeof a);
+            }
+            while (a());
+        })();
+    }
+    expect_stdout: "function"
+}

test/compress/loops.js

@@ -646,3 +646,30 @@ issue_2904: {
     }
     expect_stdout: "1"
 }
+
+issue_3371: {
+    options = {
+        functions: true,
+        join_vars: true,
+        loops: true,
+        reduce_vars: true,
+        unused: true,
+    }
+    input: {
+        (function() {
+            var a = function() {
+                console.log("PASS");
+            };
+            while (a());
+        })();
+    }
+    expect: {
+        (function() {
+            function a() {
+                console.log("PASS");
+            }
+            for (; a(); );
+        })();
+    }
+    expect_stdout: "PASS"
+}

test/compress/reduce_vars.js

@@ -281,8 +281,8 @@ unsafe_evaluate_escaped: {
         console.log(function(){ var o={p:3},a=[o]; console.log(a[0].p++); return o.p; }());
     }
     expect: {
-        console.log(function(){ var o={p:1}; console.log(o, o.p); return o.p; }());
+        console.log(function(){ var o={p:1}; console.log(o, 1); return o.p; }());
-        console.log(function(){ var o={p:2}; console.log(o.p, o); return o.p; }());
+        console.log(function(){ var o={p:2}; console.log(2, o); return o.p; }());
         console.log(function(){ var o={p:3},a=[o]; console.log(a[0].p++); return o.p; }());
     }
     expect_stdout: true

tools/props.html

@@ -1,61 +1,540 @@
+<!doctype html>
 <html>
-  <head>
+<body>
-  </head>
+    <script>
-  <body>
+        !function() {
-    <script>(function(){
+            var names = [];
-      var props = {};
+            var scanned = [];
+            var to_scan = [];
 
-      function addObject(obj) {
+            function scan(obj) {
-        if (obj == null) return;
+                if (obj && typeof obj == "object" && !~scanned.indexOf(obj)) {
+                    scanned.push(obj);
+                    to_scan.push(obj);
+                }
+            }
+
+            scan(self);
+            [
+                "a",
+                "abbr",
+                "acronym",
+                "address",
+                "applet",
+                "area",
+                "article",
+                "aside",
+                "audio",
+                "b",
+                "base",
+                "basefont",
+                "bdi",
+                "bdo",
+                "bgsound",
+                "big",
+                "blink",
+                "blockquote",
+                "body",
+                "br",
+                "button",
+                "canvas",
+                "caption",
+                "center",
+                "checked",
+                "cite",
+                "code",
+                "col",
+                "colgroup",
+                "command",
+                "comment",
+                "compact",
+                "content",
+                "data",
+                "datalist",
+                "dd",
+                "declare",
+                "defer",
+                "del",
+                "details",
+                "dfn",
+                "dialog",
+                "dir",
+                "disabled",
+                "div",
+                "dl",
+                "dt",
+                "element",
+                "em",
+                "embed",
+                "fieldset",
+                "figcaption",
+                "figure",
+                "font",
+                "footer",
+                "form",
+                "frame",
+                "frameset",
+                "h1",
+                "h2",
+                "h3",
+                "h4",
+                "h5",
+                "h6",
+                "head",
+                "header",
+                "hgroup",
+                "hr",
+                "html",
+                "i",
+                "iframe",
+                "image",
+                "img",
+                "input",
+                "ins",
+                "isindex",
+                "ismap",
+                "kbd",
+                "keygen",
+                "label",
+                "legend",
+                "li",
+                "link",
+                "listing",
+                "main",
+                "map",
+                "mark",
+                "marquee",
+                "math",
+                "menu",
+                "menuitem",
+                "meta",
+                "meter",
+                "multicol",
+                "multiple",
+                "nav",
+                "nobr",
+                "noembed",
+                "noframes",
+                "nohref",
+                "noresize",
+                "noscript",
+                "noshade",
+                "nowrap",
+                "object",
+                "ol",
+                "optgroup",
+                "option",
+                "output",
+                "p",
+                "param",
+                "picture",
+                "plaintext",
+                "pre",
+                "progress",
+                "q",
+                "rb",
+                "readonly",
+                "rp",
+                "rt",
+                "rtc",
+                "ruby",
+                "s",
+                "samp",
+                "script",
+                "section",
+                "select",
+                "selected",
+                "shadow",
+                "small",
+                "source",
+                "spacer",
+                "span",
+                "strike",
+                "strong",
+                "style",
+                "sub",
+                "summary",
+                "sup",
+                "svg",
+                "table",
+                "tbody",
+                "td",
+                "template",
+                "textarea",
+                "tfoot",
+                "th",
+                "thead",
+                "time",
+                "title",
+                "tr",
+                "track",
+                "tt",
+                "u",
+                "ul",
+                "var",
+                "video",
+                "wbr",
+                "xmp",
+                "XXX",
+            ].forEach(function(tag) {
+                scan(document.createElement(tag));
+            });
+            [
+                "abort",
+                "absolutedeviceorientation",
+                "activate",
+                "active",
+                "addsourcebuffer",
+                "addstream",
+                "addtrack",
+                "afterprint",
+                "afterscriptexecute",
+                "afterupdate",
+                "animationcancel",
+                "animationend",
+                "animationiteration",
+                "animationstart",
+                "appinstalled",
+                "audioend",
+                "audioprocess",
+                "audiostart",
+                "autocomplete",
+                "autocompleteerror",
+                "auxclick",
+                "beforeactivate",
+                "beforecopy",
+                "beforecut",
+                "beforedeactivate",
+                "beforeeditfocus",
+                "beforeinstallprompt",
+                "beforepaste",
+                "beforeprint",
+                "beforescriptexecute",
+                "beforeunload",
+                "beforeupdate",
+                "blocked",
+                "blur",
+                "bounce",
+                "boundary",
+                "cached",
+                "cancel",
+                "candidatewindowhide",
+                "candidatewindowshow",
+                "candidatewindowupdate",
+                "canplay",
+                "canplaythrough",
+                "cellchange",
+                "change",
+                "chargingchange",
+                "chargingtimechange",
+                "checking",
+                "click",
+                "close",
+                "compassneedscalibration",
+                "complete",
+                "connect",
+                "connecting",
+                "connectionstatechange",
+                "contextmenu",
+                "controllerchange",
+                "controlselect",
+                "copy",
+                "cuechange",
+                "cut",
+                "dataavailable",
+                "datachannel",
+                "datasetchanged",
+                "datasetcomplete",
+                "dblclick",
+                "deactivate",
+                "devicechange",
+                "devicelight",
+                "devicemotion",
+                "deviceorientation",
+                "deviceorientationabsolute",
+                "deviceproximity",
+                "dischargingtimechange",
+                "disconnect",
+                "display",
+                "downloading",
+                "drag",
+                "dragend",
+                "dragenter",
+                "dragexit",
+                "dragleave",
+                "dragover",
+                "dragstart",
+                "drop",
+                "durationchange",
+                "emptied",
+                "encrypted",
+                "end",
+                "ended",
+                "enter",
+                "enterpictureinpicture",
+                "error",
+                "errorupdate",
+                "exit",
+                "filterchange",
+                "finish",
+                "focus",
+                "focusin",
+                "focusout",
+                "freeze",
+                "fullscreenchange",
+                "fullscreenerror",
+                "gesturechange",
+                "gestureend",
+                "gesturestart",
+                "gotpointercapture",
+                "hashchange",
+                "help",
+                "icecandidate",
+                "iceconnectionstatechange",
+                "icegatheringstatechange",
+                "inactive",
+                "input",
+                "invalid",
+                "keydown",
+                "keypress",
+                "keyup",
+                "languagechange",
+                "layoutcomplete",
+                "leavepictureinpicture",
+                "levelchange",
+                "load",
+                "loadeddata",
+                "loadedmetadata",
+                "loadend",
+                "loading",
+                "loadingdone",
+                "loadingerror",
+                "loadstart",
+                "losecapture",
+                "lostpointercapture",
+                "mark",
+                "message",
+                "messageerror",
+                "mousedown",
+                "mouseenter",
+                "mouseleave",
+                "mousemove",
+                "mouseout",
+                "mouseover",
+                "mouseup",
+                "mousewheel",
+                "move",
+                "moveend",
+                "movestart",
+                "mozfullscreenchange",
+                "mozfullscreenerror",
+                "mozorientationchange",
+                "mozpointerlockchange",
+                "mozpointerlockerror",
+                "mscontentzoom",
+                "msfullscreenchange",
+                "msfullscreenerror",
+                "msgesturechange",
+                "msgesturedoubletap",
+                "msgestureend",
+                "msgesturehold",
+                "msgesturestart",
+                "msgesturetap",
+                "msgotpointercapture",
+                "msinertiastart",
+                "mslostpointercapture",
+                "msmanipulationstatechanged",
+                "msneedkey",
+                "msorientationchange",
+                "mspointercancel",
+                "mspointerdown",
+                "mspointerenter",
+                "mspointerhover",
+                "mspointerleave",
+                "mspointermove",
+                "mspointerout",
+                "mspointerover",
+                "mspointerup",
+                "mssitemodejumplistitemremoved",
+                "msthumbnailclick",
+                "negotiationneeded",
+                "nomatch",
+                "noupdate",
+                "obsolete",
+                "offline",
+                "online",
+                "open",
+                "orientationchange",
+                "pagechange",
+                "pagehide",
+                "pageshow",
+                "paste",
+                "pause",
+                "play",
+                "playing",
+                "pluginstreamstart",
+                "pointercancel",
+                "pointerdown",
+                "pointerenter",
+                "pointerleave",
+                "pointerlockchange",
+                "pointerlockerror",
+                "pointermove",
+                "pointerout",
+                "pointerover",
+                "pointerup",
+                "popstate",
+                "progress",
+                "propertychange",
+                "ratechange",
+                "reading",
+                "readystatechange",
+                "rejectionhandled",
+                "removesourcebuffer",
+                "removestream",
+                "removetrack",
+                "reset",
+                "resize",
+                "resizeend",
+                "resizestart",
+                "resourcetimingbufferfull",
+                "result",
+                "resume",
+                "rowenter",
+                "rowexit",
+                "rowsdelete",
+                "rowsinserted",
+                "scroll",
+                "search",
+                "seeked",
+                "seeking",
+                "select",
+                "selectionchange",
+                "selectstart",
+                "show",
+                "signalingstatechange",
+                "soundend",
+                "soundstart",
+                "sourceclose",
+                "sourceclosed",
+                "sourceended",
+                "sourceopen",
+                "speechend",
+                "speechstart",
+                "stalled",
+                "start",
+                "statechange",
+                "stop",
+                "storage",
+                "storagecommit",
+                "submit",
+                "success",
+                "suspend",
+                "textinput",
+                "timeout",
+                "timeupdate",
+                "toggle",
+                "touchcancel",
+                "touchend",
+                "touchmove",
+                "touchstart",
+                "track",
+                "transitioncancel",
+                "transitionend",
+                "transitionrun",
+                "transitionstart",
+                "unhandledrejection",
+                "unload",
+                "updateready",
+                "upgradeneeded",
+                "userproximity",
+                "versionchange",
+                "visibilitychange",
+                "voiceschanged",
+                "volumechange",
+                "vrdisplayactivate",
+                "vrdisplayconnect",
+                "vrdisplaydeactivate",
+                "vrdisplaydisconnect",
+                "vrdisplaypresentchange",
+                "waiting",
+                "waitingforkey",
+                "warning",
+                "webkitanimationend",
+                "webkitanimationiteration",
+                "webkitanimationstart",
+                "webkitcurrentplaybacktargetiswirelesschanged",
+                "webkitfullscreenchange",
+                "webkitfullscreenerror",
+                "webkitkeyadded",
+                "webkitkeyerror",
+                "webkitkeymessage",
+                "webkitneedkey",
+                "webkitorientationchange",
+                "webkitplaybacktargetavailabilitychanged",
+                "webkitpointerlockchange",
+                "webkitpointerlockerror",
+                "webkitresourcetimingbufferfull",
+                "webkittransitionend",
+                "wheel",
+                "zoom",
+            ].forEach(function(type) {
+                [
+                    "beforeunloadevent",
+                    "compositionevent",
+                    "customevent",
+                    "devicemotionevent",
+                    "deviceorientationevent",
+                    "dragevent",
+                    "event",
+                    "events",
+                    "focusevent",
+                    "hashchangeevent",
+                    "htmlevents",
+                    "keyboardevent",
+                    "messageevent",
+                    "mouseevent",
+                    "mouseevents",
+                    "storageevent",
+                    "svgevents",
+                    "textevent",
+                    "touchevent",
+                    "uievent",
+                    "uievents",
+                ].forEach(function(interface) {
                     try {
-          Object.getOwnPropertyNames(obj).forEach(add);
+                        var event = document.createEvent(interface);
-        } catch(ex) {}
+                        event.initEvent(type, true, true);
-        if (obj.prototype) {
+                        scan(event);
-          Object.getOwnPropertyNames(obj.prototype).forEach(add);
+                    } catch (e) {}
-        }
+                });
-        if (typeof obj == "function") {
-          try {
-            Object.getOwnPropertyNames(new obj).forEach(add);
-          } catch(ex) {}
-        }
-      }
-
-      function add(name) {
-        props[name] = true;
-      }
-
-      Object.getOwnPropertyNames(window).forEach(function(thing){
-        addObject(window[thing]);
             });
 
+            var obj;
+            while (obj = to_scan.shift()) {
+                var proto = obj;
+                do {
+                    Object.getOwnPropertyNames(proto).forEach(function(name) {
+                        var visited = ~names.indexOf(name);
+                        if (!visited) names.push(name);
                         try {
-        addObject(new Event("click"));
+                            scan(obj[name]);
-        addObject(new Event("contextmenu"));
+                            if (visited) return;
-        addObject(new Event("mouseup"));
+                            if (/^create/.test(name)) {
-        addObject(new Event("mousedown"));
+                                scan(obj[name]());
-        addObject(new Event("keydown"));
-        addObject(new Event("keypress"));
-        addObject(new Event("keyup"));
-      } catch(ex) {}
-
-      var ta = document.createElement("textarea");
-      ta.style.width = "100%";
-      ta.style.height = "20em";
-      ta.style.boxSizing = "border-box";
-      <!-- ta.value = Object.keys(props).sort(cmp).map(function(name){ -->
-      <!--   return JSON.stringify(name); -->
-      <!-- }).join(",\n"); -->
-      ta.value = JSON.stringify({
-        vars: [],
-        props: Object.keys(props).sort(cmp)
-      }, null, 2);
-      document.body.appendChild(ta);
-
-      function cmp(a, b) {
-        a = a.toLowerCase();
-        b = b.toLowerCase();
-        return a < b ? -1 : a > b ? 1 : 0;
                             }
-    })();</script>
+                            if (/^[A-Z]/.test(name)) {
-  </body>
+                                scan(new obj[name]());
+                            }
+                        } catch (e) {}
+                    });
+                } while (proto = Object.getPrototypeOf(proto));
+            }
+            names.sort();
+            document.write('<pre>[\n    "');
+            document.write(names.join('",\n    "'));
+            document.write('"\n]</pre>');
+        }();
+    </script>
+</body>
 </html>