Fix circular references in JSON test log serialization.

src/tiledimage.js

@@ -2107,8 +2107,6 @@ $.extend($.TiledImage.prototype, $.EventSource.prototype, /** @lends OpenSeadrag
         }
 
         this._setTileLoaded(tile, data, null, tileRequest, dataType);
-
-        //TODO aiosa missing timeout might damage the cache system
     },
 
     /**

test/helpers/test.js

@@ -180,14 +180,36 @@
             }
         };
 
+    // OSD has circular references, if a console log tries to serialize
+    // certain object, remove these references from a clone (do not delete prop
+    // on the original object).
+    // NOTE: this does not work if someone replaces the original class with
+    // a mock object! Try to mock functions only, or ensure mock objects
+    // do not hold circular references.
+    const circularOSDReferences = {
+        'Tile': 'tiledImage',
+        'World': 'viewer',
+        'DrawerBase': ['viewer', 'viewport'],
+        'CanvasDrawer': ['viewer', 'viewport'],
+        'WebGLDrawer': ['viewer', 'viewport'],
+        'TiledImage': ['viewer', '_drawer'],
+    };
     for ( var i in testLog ) {
         if ( testLog.hasOwnProperty( i ) && testLog[i].push ) {
-            //Tile.tiledImage creates circular reference, copy object to avoid and allow JSON serialization
+            // Circular reference removal
-            const tileCircularStructureReplacer = function (key, value) {
+            const osdCircularStructureReplacer = function (key, value) {
-                if (value instanceof OpenSeadragon.Tile) {
+                for (let ClassType in circularOSDReferences) {
-                    var instance = {};
+                    if (value instanceof OpenSeadragon[ClassType]) {
+                        const instance = {};
                         Object.assign(instance, value);
-                    delete value.tiledImage;
+
+                        let circProps = circularOSDReferences[ClassType];
+                        if (!Array.isArray(circProps)) circProps = [circProps];
+                        for (let prop of circProps) {
+                            instance[prop] = '__circular_reference__';
+                        }
+                        return instance;
+                    }
                 }
                 return value;
             };
@@ -195,7 +217,7 @@
             testConsole[i] = ( function ( arr ) {
                 return function () {
                     var args = Array.prototype.slice.call( arguments, 0 ); // Coerce to true Array
-                    arr.push( JSON.stringify( args, tileCircularStructureReplacer ) ); // Store as JSON to avoid tedious array-equality tests
+                    arr.push( JSON.stringify( args, osdCircularStructureReplacer ) ); // Store as JSON to avoid tedious array-equality tests
                 };
             } )( testLog[i] );
 

test/modules/tilesource-dynamic-url.js

@@ -8,7 +8,7 @@
     var DYNAMIC_URL = "";
     var viewer = null;
     var OriginalAjax = OpenSeadragon.makeAjaxRequest;
-    var OriginalTile = OpenSeadragon.Tile;
+    var OriginalTileGetUrl = OpenSeadragon.Tile.prototype.getUrl;
     // These variables allow tracking when the first request for data has finished
     var firstUrlPromise = null;
     var isFirstUrlPromiseResolved = false;
@@ -115,22 +115,15 @@
                 return request;
             };
 
-            // Override Tile to ensure getUrl is called successfully.
+            // Override Tile::getUrl to ensure getUrl is called successfully.
-            var Tile = function(...params) {
+            OpenSeadragon.Tile.prototype.getUrl = function () {
-                OriginalTile.apply(this, params);
-            };
-
-            OpenSeadragon.extend( Tile.prototype, OpenSeadragon.Tile.prototype, {
-                getUrl: function() {
                 // if ASSERT is still truthy, call ASSERT.ok. If the viewer
                 // has already been destroyed and ASSERT has set to null, ignore this
                 if (ASSERT) {
                     ASSERT.ok(true, 'Tile.getUrl called');
                 }
-                    return OriginalTile.prototype.getUrl.apply(this);
+                return OriginalTileGetUrl.apply(this, arguments);
-                }
+            };
-            });
-            OpenSeadragon.Tile = Tile;
         },
 
         afterEach: function () {
@@ -143,7 +136,7 @@
             viewer = null;
 
             OpenSeadragon.makeAjaxRequest = OriginalAjax;
-            OpenSeadragon.Tile = OriginalTile;
+            OpenSeadragon.Tile.prototype.getUrl = OriginalTileGetUrl;
         }
     });