1 files changed, 138 insertions, 0 deletions
diff --git a/image/test/mochitest/imgutils.js b/image/test/mochitest/imgutils.js
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+++ b/image/test/mochitest/imgutils.js
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+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+// Helper file for shared image functionality
+// 
+// Note that this is use by tests elsewhere in the source tree. When in doubt,
+// check mxr before removing or changing functionality.
+
+// Helper function to clear both the content and chrome image caches
+function clearAllImageCaches()
+{
+  var tools = SpecialPowers.Cc["@mozilla.org/image/tools;1"]
+                             .getService(SpecialPowers.Ci.imgITools);
+  var imageCache = tools.getImgCacheForDocument(window.document);
+  imageCache.clearCache(true);  // true=chrome
+  imageCache.clearCache(false); // false=content
+}
+
+// Helper function to clear the image cache of content images
+function clearImageCache()
+{
+  var tools = SpecialPowers.Cc["@mozilla.org/image/tools;1"]
+                             .getService(SpecialPowers.Ci.imgITools);
+  var imageCache = tools.getImgCacheForDocument(window.document);
+  imageCache.clearCache(false); // true=chrome, false=content
+}
+
+// Helper function to determine if the frame is decoded for a given image id
+function isFrameDecoded(id)
+{
+  return (getImageStatus(id) &
+          SpecialPowers.Ci.imgIRequest.STATUS_FRAME_COMPLETE)
+         ? true : false;
+}
+
+// Helper function to determine if the image is loaded for a given image id
+function isImageLoaded(id)
+{
+  return (getImageStatus(id) &
+          SpecialPowers.Ci.imgIRequest.STATUS_LOAD_COMPLETE)
+         ? true : false;
+}
+
+// Helper function to get the status flags of an image
+function getImageStatus(id)
+{
+  // Get the image
+  var img = SpecialPowers.wrap(document.getElementById(id));
+
+  // QI the image to nsImageLoadingContent
+  img.QueryInterface(SpecialPowers.Ci.nsIImageLoadingContent);
+
+  // Get the request
+  var request = img.getRequest(SpecialPowers.Ci
+                                         .nsIImageLoadingContent
+                                         .CURRENT_REQUEST);
+
+  // Return the status
+  return request.imageStatus;
+}
+
+// Forces a synchronous decode of an image by drawing it to a canvas. Only
+// really meaningful if the image is fully loaded first
+function forceDecode(id)
+{
+  // Get the image
+  var img = document.getElementById(id);
+
+  // Make a new canvas
+  var canvas = document.createElement("canvas");
+
+  // Draw the image to the canvas. This forces a synchronous decode
+  var ctx = canvas.getContext("2d");
+  ctx.drawImage(img, 0, 0);
+}
+
+
+// Functions to facilitate getting/setting various image-related prefs
+//
+// If you change a pref in a mochitest, Don't forget to reset it to its 
+// original value!
+//
+// Null indicates no pref set
+
+const DISCARD_ENABLED_PREF = {name: "discardable", branch: "image.mem.", type: "bool"};
+const DECODEONDRAW_ENABLED_PREF = {name: "decodeondraw", branch: "image.mem.", type: "bool"};
+const DISCARD_TIMEOUT_PREF = {name: "min_discard_timeout_ms", branch: "image.mem.", type: "int"};
+
+function setImagePref(pref, val)
+{
+  var prefService = SpecialPowers.Cc["@mozilla.org/preferences-service;1"]
+                                 .getService(SpecialPowers.Ci.nsIPrefService);
+  var branch = prefService.getBranch(pref.branch);
+  if (val != null) {
+    switch(pref.type) {
+      case "bool":
+        branch.setBoolPref(pref.name, val);
+        break;
+      case "int":
+        branch.setIntPref(pref.name, val);
+        break;
+      default:
+        throw new Error("Unknown pref type");
+    }
+  }
+  else if (branch.prefHasUserValue(pref.name))
+    branch.clearUserPref(pref.name);
+}
+
+function getImagePref(pref)
+{
+  var prefService = SpecialPowers.Cc["@mozilla.org/preferences-service;1"]
+                                 .getService(SpecialPowers.Ci.nsIPrefService);
+  var branch = prefService.getBranch(pref.branch);
+  if (branch.prefHasUserValue(pref.name)) {
+    switch (pref.type) {
+      case "bool":
+        return branch.getBoolPref(pref.name);
+      case "int":
+        return branch.getIntPref(pref.name);
+      default:
+        throw new Error("Unknown pref type");
+    }
+  }
+  else
+    return null;
+}
+
+// JS implementation of imgIScriptedNotificationObserver with stubs for all of its methods.
+function ImageDecoderObserverStub()
+{
+  this.sizeAvailable = function sizeAvailable(aRequest)     {}
+  this.frameComplete = function frameComplete(aRequest)     {}
+  this.decodeComplete = function decodeComplete(aRequest)   {}
+  this.loadComplete = function loadComplete(aRequest)       {}
+  this.frameUpdate = function frameUpdate(aRequest)         {}
+  this.discard = function discard(aRequest)                 {}
+  this.isAnimated = function isAnimated(aRequest)           {}
+  this.hasTransparency = function hasTransparency(aRequest) {}
+}