Cleanup proxyWorker.js and use arrow functions. NFC (#19604)

Author: sbc100

src/proxyClient.js

@@ -4,7 +4,16 @@
  * SPDX-License-Identifier: MIT
  */
 
-// proxy to/from worker
+/*
+ * Proxy events/work to/from an emscripen worker built
+ * with PROXY_TO_WORKER.  This code runs on the main
+ * thread and is not part of the main emscripten output
+ * file.
+ */
+
+#if !PROXY_TO_WORKER
+#error "proxyClient.js should only be included in PROXY_TO_WORKER mode"
+#endif
 
 #if ENVIRONMENT_MAY_BE_NODE
 var ENVIRONMENT_IS_NODE = typeof process == 'object' && typeof process.versions == 'object' && typeof process.versions.node == 'string';

src/proxyWorker.js

@@ -5,16 +5,16 @@
  */
 
 /*
-function proxify(object, nick) {
-  return new Proxy(object, {
-    get: function(target, name) {
-      var ret = target[name];
-      if (ret === undefined) console.log('PROXY ' + [nick, target, name, ret, typeof ret]);
-      return ret;
-    }
-  });
-}
-*/
+ * Implements the server/worker side of proxyClient.js.
+ * This code gets included in the main emscripten output
+ * when PROXY_TO_WORKER is used. The resulting code then
+ * needs to be run in a worker and receive events from
+ * proxyClient.js running on the main thread.
+ */
+
+#if !PROXY_TO_WORKER
+#error "proxyClient.js should only be included in PROXY_TO_WORKER mode"
+#endif
 
 #if ENVIRONMENT_MAY_BE_NODE
 if (!ENVIRONMENT_IS_NODE) {
@@ -24,7 +24,7 @@ function FPSTracker(text) {
   var last = 0;
   var mean = 0;
   var counter = 0;
-  this.tick = function() {
+  this.tick = () => {
     var now = Date.now();
     if (last > 0) {
       var diff = now - last;
@@ -47,9 +47,9 @@ var KeyboardEvent = {
 };
 
 function PropertyBag() {
-  this.addProperty = function(){};
-  this.removeProperty = function(){};
-  this.setProperty = function(){};
+  this.addProperty = () => {};
+  this.removeProperty = () => {};
+  this.setProperty = () => {};
 };
 
 var IndexedObjects = {
@@ -77,44 +77,42 @@ function EventListener() {
     list.splice(me, 1);
   };
 
-  this.fireEvent = function fireEvent(event) {
-    event.preventDefault = function(){};
+  this.fireEvent = function(event) {
+    event.preventDefault = () => {};
 
     if (event.type in this.listeners) {
       this.listeners[event.type].forEach((listener) => listener(event));
     }
-  };
+  }
 }
 
 function Image() {
   IndexedObjects.add(this);
   EventListener.call(this);
   var src = '';
   Object.defineProperty(this, 'src', {
-    set: function(value) {
+    set: (value) => {
       src = value;
       assert(this.id);
       postMessage({ target: 'Image', method: 'src', src, id: this.id });
     },
-    get: function() {
-      return src;
-    }
+    get: () => src
   });
 }
-Image.prototype.onload = function(){};
-Image.prototype.onerror = function(){};
+Image.prototype.onload = () => {};
+Image.prototype.onerror = () => {};
 
 var HTMLImageElement = Image;
 
 var window = this;
 var windowExtra = new EventListener();
 for (var x in windowExtra) window[x] = windowExtra[x];
 
-window.close = function window_close() {
+window.close = () => {
   postMessage({ target: 'window', method: 'close' });
 };
 
-window.alert = function(text) {
+window.alert = (text) => {
   err('alert forever: ' + text);
   while (1) {};
 };
@@ -145,11 +143,11 @@ var webGLWorker = new WebGLWorker();
 
 var document = new EventListener();
 
-document.createElement = function document_createElement(what) {
+document.createElement = (what) => {
   switch (what) {
     case 'canvas': {
       var canvas = new EventListener();
-      canvas.ensureData = function canvas_ensureData() {
+      canvas.ensureData = () => {
         if (!canvas.data || canvas.data.width !== canvas.width || canvas.data.height !== canvas.height) {
           canvas.data = {
             width: canvas.width,
@@ -161,13 +159,13 @@ document.createElement = function document_createElement(what) {
           }
         }
       };
-      canvas.getContext = function canvas_getContext(type, attributes) {
+      canvas.getContext = (type, attributes) => {
         if (canvas === Module['canvas']) {
           postMessage({ target: 'canvas', op: 'getContext', type, attributes });
         }
         if (type === '2d') {
           return {
-            getImageData: function(x, y, w, h) {
+            getImageData: (x, y, w, h) => {
               assert(x == 0 && y == 0 && w == canvas.width && h == canvas.height);
               canvas.ensureData();
               return {
@@ -176,15 +174,15 @@ document.createElement = function document_createElement(what) {
                 data: new Uint8Array(canvas.data.data) // TODO: can we avoid this copy?
               };
             },
-            putImageData: function(image, x, y) {
+            putImageData: (image, x, y) => {
               canvas.ensureData();
               assert(x == 0 && y == 0 && image.width == canvas.width && image.height == canvas.height);
               canvas.data.data.set(image.data); // TODO: can we avoid this copy?
               if (canvas === Module['canvas']) {
                 postMessage({ target: 'canvas', op: 'render', image: canvas.data });
               }
             },
-            drawImage: function(image, x, y, w, h, ox, oy, ow, oh) {
+            drawImage: (image, x, y, w, h, ox, oy, ow, oh) => {
               assert (!x && !y && !ox && !oy);
               assert(w === ow && h === oh);
               assert(canvas.width === w || w === undefined);
@@ -202,7 +200,7 @@ document.createElement = function document_createElement(what) {
         }
       };
       canvas.boundingClientRect = {};
-      canvas.getBoundingClientRect = function canvas_getBoundingClientRect() {
+      canvas.getBoundingClientRect = () => {
         return {
           width: canvas.boundingClientRect.width,
           height: canvas.boundingClientRect.height,
@@ -213,69 +211,68 @@ document.createElement = function document_createElement(what) {
         };
       };
       canvas.style = new PropertyBag();
-      canvas.exitPointerLock = function(){};
+      canvas.exitPointerLock = () => {};
 
       canvas.width_ = canvas.width_ || 0;
       canvas.height_ = canvas.height_ || 0;
       Object.defineProperty(canvas, 'width', {
-        set: function(value) {
+        set: (value) => {
           canvas.width_ = value;
           if (canvas === Module['canvas']) {
             postMessage({ target: 'canvas', op: 'resize', width: canvas.width_, height: canvas.height_ });
           }
         },
-        get: function() {
+        get: () => {
           return canvas.width_;
         }
       });
       Object.defineProperty(canvas, 'height', {
-        set: function(value) {
+        set: (value) => {
           canvas.height_ = value;
           if (canvas === Module['canvas']) {
             postMessage({ target: 'canvas', op: 'resize', width: canvas.width_, height: canvas.height_ });
           }
         },
-        get: function() {
+        get: () => {
           return canvas.height_;
         }
       });
 
       var style = {
         parentCanvas: canvas,
-        removeProperty: function(){},
-        setProperty:  function(){},
+        removeProperty: () => {},
+        setProperty:  () => {},
       };
 
       Object.defineProperty(style, 'cursor', {
-        set: function(value) {
+        set: (value) => {
           if (!style.cursor_ || style.cursor_ !== value) {
             style.cursor_ = value;
             if (style.parentCanvas === Module['canvas']) {
               postMessage({ target: 'canvas', op: 'setObjectProperty', object: 'style', property: 'cursor', value: style.cursor_ });
             }
           }
         },
-        get: function() {
-          return style.cursor_;
-        }
+        get: () => style.cursor,
       });
 
       canvas.style = style;
-
       return canvas;
     }
-    default: throw 'document.createElement ' + what;
+    default: {
+      throw 'document.createElement ' + what;
+    }
   }
 };
 
-document.getElementById = function(id) {
+document.getElementById = (id) => {
   if (id === 'canvas' || id === 'application-canvas') {
     return Module.canvas;
   }
   throw 'document.getElementById failed on ' + id;
 };
 
-document.querySelector = function(id) {
+document.querySelector = (id) => {
   if (id === '#canvas' || id === '#application-canvas' || id === 'canvas' || id === 'application-canvas') {
     return Module.canvas;
   }
@@ -304,26 +301,24 @@ Object.defineProperty(Audio.prototype, 'src', {
   },
 });
 
-Audio.prototype.play = function(){};
-Audio.prototype.pause = function(){};
+Audio.prototype.play = () => {};
+Audio.prototype.pause = () => {};
 
-Audio.prototype.cloneNode = function() {
-  return new Audio;
-}
+Audio.prototype.cloneNode = () => new Audio;
 
 function AudioContext() {
   warnOnce('faking WebAudio elements, no actual sound will play');
-  function makeNode() {
+  var makeNode = () => {
     return {
-      connect: function(){},
-      disconnect: function(){},
+      connect: () => {},
+      disconnect: () => {},
     }
-  }
+  };
   this.listener = {
-    setPosition: function() {},
-    setOrientation: function() {},
+    setPosition: () => {},
+    setOrientation: () => {},
   };
-  this.decodeAudioData = function() {}; // ignore callbacks
+  this.decodeAudioData = () => {}; // ignore callbacks
   this.createBuffer = makeNode;
   this.createBufferSource = makeNode;
   this.createGain = makeNode;
@@ -339,11 +334,11 @@ Module.canvas = document.createElement('canvas');
 
 Module.setStatus = () => {};
 
-out = function(x) {
+out = (x) => {
   //dump('OUT: ' + x + '\n');
   postMessage({ target: 'stdout', content: x });
 };
-err = function(x) {
+err = (x) => {
   //dump('ERR: ' + x + '\n');
   postMessage({ target: 'stderr', content: x });
 };
@@ -354,7 +349,7 @@ var frameId = 0;
 var clientFrameId = 0;
 
 var postMainLoop = Module['postMainLoop'];
-Module['postMainLoop'] = function() {
+Module['postMainLoop'] = () => {
   if (postMainLoop) postMainLoop();
   // frame complete, send a frame id
   postMessage({ target: 'tick', id: frameId++ });