Print Preview: Make generate draft mode work again.

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 66 matching lines @@
    * Stub out low-level functionality like the NativeLayer and
    * CloudPrintInterface.
    * @this {PrintPreviewWebUITest}
    * @override
    */
   preLoad: function() {
     window.addEventListener('DOMContentLoaded', function() {
       function NativeLayerStub() {
         cr.EventTarget.call(this);
         this.printStarted_ = false;
+        this.generateDraft_ = false;
       }
       NativeLayerStub.prototype = {
         __proto__: cr.EventTarget.prototype,
         isPrintStarted: function() { return this.printStarted_; },
+        generateDraft: function() { return this.generateDraft_; },
         previewReadyForTest: function() {},
         startGetInitialSettings: function() {},
         startGetLocalDestinations: function() {},
         startGetPrivetDestinations: function() {},
         startGetExtensionDestinations: function() {},
         startGetLocalDestinationCapabilities: function(destinationId) {},
-        startGetPreview: function() {},
+        startGetPreview: function(destination, printTicketStore, documentInfo,
+                                  generateDraft, requestId) {
+          this.generateDraft_ = generateDraft;
+        },
         startHideDialog: function () {},
         startPrint: function () { this.printStarted_ = true; }
       };
       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() {
@@ skipping 62 matching lines @@
    * Dispatch the SETTINGS_INVALID event. This call is NOT async and will
    * happen in the same thread.
    */
   dispatchInvalidSettings: function() {
     var invalidSettingsEvent =
         new Event(print_preview.NativeLayer.EventType.SETTINGS_INVALID);
     this.nativeLayer_.dispatchEvent(invalidSettingsEvent);
   },
 
   /**
-   * @return {boolean} Whether the UI has/has not "printed" (called startPrint
-   *     on the native layer).
+   * @return {boolean} Whether the UI has "printed" or not. (called startPrint
+   *     on the native layer)
    */
   hasPrinted: function() {
     return this.nativeLayer_.isPrintStarted();
   },
 
   /**
+   * @return {boolean} Whether the UI is "generating draft" in the most recent
+   *     preview. (checking the result of the startGetPreview call in the native
+   *     layer)
+   */
+  generateDraft: function() {
+    return this.nativeLayer_.generateDraft();
+  },
+
+  /**
    * Even though animation duration and delay is set to zero, it is necessary to
    * wait until the animation has finished.
    */
   waitForAnimationToEnd: function(elementId) {
     // add a listener for the animation end event
     document.addEventListener('animationend', function f(e) {
       if (e.target.id == elementId) {
         document.removeEventListener(f, 'animationend');
         testDone();
       }
@@ skipping 1244 matching lines @@
   this.dispatchPreviewDone();
 
   // Has active print button and successfully "prints", indicating recovery
   // from error state.
   expectFalse(printButton.disabled);
   expectFalse(this.hasPrinted());
   printButton.click();
   expectTrue(this.hasPrinted());
   testDone();
 });
+
+// Test the preview generator to make sure the generate draft parameter is set
+// correctly. It should be false if the only change is the page range.
+TEST_F('PrintPreviewWebUITest', 'TestGenerateDraft', function() {
+  // Use a real preview generator.
+  printPreview.previewArea_.previewGenerator_ =
+      new print_preview.PreviewGenerator(printPreview.destinationStore_,
+        printPreview.printTicketStore_, this.nativeLayer_,
+        printPreview.documentInfo_);
+
+  this.setInitialSettings();
+  this.setLocalDestinations();
+  this.setCapabilities(getCddTemplate("FooDevice"));
+
+  // The first request should generate draft because there was no previous print
+  // preview draft.
+  expectTrue(this.generateDraft());
+
+  // Change the page range - no new draft needed.
+  printPreview.printTicketStore_.pageRange.updateValue("2");
+  expectFalse(this.generateDraft());

[dpapad, 2017/05/05 18:28:49]

Thanks. This looks good for now. Eventually when we switch NativeLayerStub to
inherit from TestBrowserProxy you could do something as follows


this.setCapabilities(getCddTemplate("FooDevice"));

return stub.whenCalled('startGetPreview').then(function(args) {
  // args[3] is |generatePreview|
  assertFalse(args[3]);

  stub.resetResolver('startGetPreview');

  printPreview.printTicketStore_.marginsType.updateValue(
      print_preview.ticket_items.MarginsTypeValue.NO_MARGINS);

  return stub.whenCalled('startGetPreview')
}).then(function(args) {
  assertTrue(args[3]);
});

+
+  // Change the margin type - need to regenerate again.
+  printPreview.printTicketStore_.marginsType.updateValue(
+      print_preview.ticket_items.MarginsTypeValue.NO_MARGINS);
+  expectTrue(this.generateDraft());
+
+  testDone();
+});