Print Preview: Add test to ensure only 1 preview is started at init

chrome/test/data/webui/print_preview.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 GEN('#include "base/feature_list.h"');
 GEN('#include "chrome/common/chrome_features.h"');
 
 /**
  * Test fixture for print preview WebUI testing.
  * @constructor
@@ skipping 75 matching lines @@
     window.addEventListener('DOMContentLoaded', function() {
       function NativeLayerStub() {
         cr.EventTarget.call(this);
       }
       NativeLayerStub.prototype = {
         __proto__: cr.EventTarget.prototype,
         startGetInitialSettings: function() {},
         startGetLocalDestinations: function() {},
         startGetPrivetDestinations: function() {},
         startGetExtensionDestinations: function() {},
-        startGetLocalDestinationCapabilities: function(destinationId) {}
+        startGetLocalDestinationCapabilities: function(destinationId) {},
+        startGetPreview: function() {},
       };
       var oldNativeLayerEventType = print_preview.NativeLayer.EventType;
       var oldDuplexMode = print_preview.NativeLayer.DuplexMode;
       print_preview.NativeLayer = NativeLayerStub;
       print_preview.NativeLayer.EventType = oldNativeLayerEventType;
       print_preview.NativeLayer.DuplexMode = oldDuplexMode;
 
       function CloudPrintInterfaceStub() {
         cr.EventTarget.call(this);
       }
@@ skipping 1165 matching lines @@
   // Check advanced settings is visible and that the search box now
   // appears.
   var advancedSettingsCloseButton = $('advanced-settings').
       querySelector('.close-button');
   checkElementDisplayed(advancedSettingsCloseButton, true);
   checkElementDisplayed($('advanced-settings').
       querySelector('.search-box-area'), true);
 
   this.waitForAnimationToEnd('more-settings');
 });
+
+// Test that initialization with saved destination only issues one call
+// to startPreview.
+TEST_F('PrintPreviewWebUITest', 'TestInitIssuesOneRequest', function() {
+  // Load in a bunch of recent destinations with non null capabilities.
+  origin = cr.isChromeOS ? 'chrome_os' : 'local';

[dpapad, 2017/01/14 02:37:00]

var origin

[rbpotter, 2017/01/17 19:51:24]

Done.

+  var initSettings = {
+    version: 2,
+    recentDestinations: [1, 2, 3].map(function(i) {
+      return {
+        id: 'ID' + i, origin: origin, account: '',
+        capabilities: getCddTemplate('ID' + i), name: '',
+        extensionId: '', extensionName: ''
+      };
+    }),
+  };
+  this.initialSettings_.serializedAppStateStr_ = JSON.stringify(initSettings);
+  this.setCapabilities(getCddTemplate('ID1'));
+  this.setCapabilities(getCddTemplate('ID2'));
+  this.setCapabilities(getCddTemplate('ID3'));
+
+  // Use a real preview generator.
+  printPreview.previewArea_.previewGenerator_ =
+    new print_preview.PreviewGenerator(printPreview.destinationStore_,

[dpapad, 2017/01/14 02:37:00]

indent off by -2

[rbpotter, 2017/01/17 19:51:24]

Done.

+      printPreview.printTicketStore_, this.nativeLayer_,
+      printPreview.documentInfo_);
+
+  // Preview generator starts out with inFlightRequestId_ == -1. The id
+  // increments by 1 for each startGetPreview call it makes. It should only
+  // make one such call during initialization or there will be a race; see
+  // crbug.com/666595
+  expectEquals(printPreview.previewArea_.previewGenerator_.inFlightRequestId_,
+    -1);
+  this.setInitialSettings();
+  expectEquals(printPreview.previewArea_.previewGenerator_.inFlightRequestId_,
+    0);
+  testDone();
+});