Print Preview: change getPreview to cr.sendWithPromise

chrome/test/data/webui/print_preview/print_preview_tests.js

 // Copyright 2016 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.
 
 cr.define('print_preview_test', function() {
   /**
    * Index of the "Save as PDF" printer.
    * @type {number}
    * @const
    */
@@ skipping 1041 matching lines @@
         // Now it should be visible.
         checkSectionVisible(otherOptions, true);
         expectTrue(otherOptions.querySelector('#duplex-container').hidden);
 
         return whenAnimationDone('more-settings');
       });
     });
 
     // Test that changing the selected printer updates the preview.
     test('PrinterChangeUpdatesPreview', function() {
+      // Preview generator
+      previewArea.previewGenerator_ =
+          new print_preview.PreviewGenerator(printPreview.destinationStore_,
+              printPreview.printTicketStore_, nativeLayer,
+              printPreview.documentInfo_);
+
       return setupSettingsAndDestinationsWithCapabilities().then(function() {
-        var previewGenerator = mock(print_preview.PreviewGenerator);
-        previewArea.previewGenerator_ = previewGenerator.proxy();
-
-        // The number of settings that can change due to a change in the
-        // destination that will therefore dispatch ticket item change events.
-        previewGenerator.expects(exactly(9)).requestPreview();
+        return nativeLayer.whenCalled('getPreview');
+      }).then(function(args0) {
+        expectEquals(0, args0.requestId);
+        expectEquals('FooDevice', args0.destination.id);
+        nativeLayer.resetResolver('getPreview');
 
         // Setup capabilities for BarDevice.
         var device = getCddTemplate('BarDevice');
         device.capabilities.printer.color = {
           'option': [
             {'is_default': true, 'type': 'STANDARD_MONOCHROME'}
           ]
         };
         nativeLayer.setLocalDestinationCapabilities(device);
-
         // Select BarDevice
         var barDestination =
             printPreview.destinationStore_.destinations().find(
                 function(d) {
                   return d.id == 'BarDevice';
                 });
         printPreview.destinationStore_.selectDestination(barDestination);
         return nativeLayer.whenCalled('getPrinterCapabilities', 'BarDevice');
       }).then(function(){
-        return whenAnimationDone('more-settings');
+        // Verify new preview is requested with new ID and destination.
+        return nativeLayer.whenCalled('getPreview');
+      }).then(function(args1) {
+        expectEquals(1, args1.requestId);
+        expectEquals('BarDevice', args1.destination.id);
       });
     });
 
     // Test that error message is displayed when plugin doesn't exist.
     test('NoPDFPluginErrorMessage', function() {
       nativeLayer.setLocalDestinationCapabilities(getCddTemplate('FooDevice'));
       setInitialSettings();
       return nativeLayer.whenCalled('getInitialSettings').then(function() {
         var previewAreaEl = $('preview-area');
 
@@ skipping 127 matching lines @@
       nativeLayer.setLocalDestinationCapabilities(getCddTemplate('ID1'));
       nativeLayer.setLocalDestinationCapabilities(getCddTemplate('ID2'))
       nativeLayer.setLocalDestinationCapabilities(getCddTemplate('ID3'));
 
       // Use a real preview generator.
       previewArea.previewGenerator_ =
           new print_preview.PreviewGenerator(printPreview.destinationStore_,
             printPreview.printTicketStore_, 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(-1, previewArea.previewGenerator_.inFlightRequestId_);
+      // For crbug.com/666595. If multiple destinations are fetched there may
+      // be multiple preview requests. This verifies the first fetch is for
+      // ID1, which ensures no other destinations are fetched earlier. The last
+      // destination retrieved before timeout will end up in the preview
+      // request. Ensure this is also ID1.

[rbpotter, 2017/06/29 01:13:53]

Note: This always catches the bug linked, as the code at
that time fetched ID3, then ID2, then ID1 (reverse order
of recency). However it may be possible for a related bug
to occur in which ID1 is fetched first, then some other ID
is fetched just enough afterward to trigger the second
preview request. I have an alternate solution that covers
this case, but it requires ~30 lines of code to be added to
NativeLayerStub and when I tried to create this failure the
test as is caught it every time I ran it locally (i.e.
ID3 always arrived before the timeout for the first request
and as a result line 1258 failed).

       setInitialSettings();
-      return nativeLayer.whenCalled('getInitialSettings').then(function() {
-        return nativeLayer.whenCalled('getPrinterCapabilities', 'ID1');
-      }).then(function() {
-        expectEquals(0, previewArea.previewGenerator_.inFlightRequestId_);
+      var initialSettingsSet = nativeLayer.whenCalled('getInitialSettings');
+      return initialSettingsSet.then(function() {
+        return nativeLayer.whenCalled('getPrinterCapabilities');
+      }).then(function(id) {
+        expectEquals('ID1', id);
+        return nativeLayer.whenCalled('getPreview');
+      }).then(function(preview_args) {
+        expectEquals(0, preview_args.requestId);
+        expectEquals('ID1', preview_args.destination.id);
       });
     });
 
     // Test that invalid settings errors disable the print preview and display
     // an error and that the preview dialog can be recovered by selecting a
     // new destination.
     test('InvalidSettingsError', function() {
       return setupSettingsAndDestinationsWithCapabilities().then(function() {
         // Manually enable the print header. This is needed since there is no
         // plugin during test, so it will be set as disabled normally.
@@ skipping 60 matching lines @@
 
     // 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('GenerateDraft', function() {
       // Use a real preview generator.
       previewArea.previewGenerator_ =
           new print_preview.PreviewGenerator(printPreview.destinationStore_,
               printPreview.printTicketStore_, nativeLayer,
               printPreview.documentInfo_);
       return setupSettingsAndDestinationsWithCapabilities().then(function() {
+        return nativeLayer.whenCalled('getPreview');
+      }).then(function(args0) {
         // The first request should generate draft because there was no
         // previous print preview draft.
-        expectTrue(nativeLayer.generateDraft());
+        expectTrue(args0.generateDraft);
+        expectEquals(0, args0.requestId);
+        nativeLayer.resetResolver('getPreview');
 
         // Change the page range - no new draft needed.
         printPreview.printTicketStore_.pageRange.updateValue('2');
-        expectFalse(nativeLayer.generateDraft());
+        return nativeLayer.whenCalled('getPreview');
+      }).then(function(args1) {
+        expectFalse(args1.generateDraft);
+        expectEquals(1, args1.requestId);
+        nativeLayer.resetResolver('getPreview');
 
         // Change the margin type - need to regenerate again.
         printPreview.printTicketStore_.marginsType.updateValue(
             print_preview.ticket_items.MarginsTypeValue.NO_MARGINS);
-        expectTrue(nativeLayer.generateDraft());
+        return nativeLayer.whenCalled('getPreview');
+      }).then(function(args2) {
+        expectTrue(args2.generateDraft);
+        expectEquals(2, args2.requestId);
       });
     });
 
     // Test that the policy to use the system default printer by default
     // instead of the most recently used destination works.
     test('SystemDefaultPrinterPolicy', function() {
       // Add recent destination.
       initialSettings.serializedAppStateStr_ = JSON.stringify({
         version: 2,
         recentDestinations: [
@@ skipping 20 matching lines @@
       return setupSettingsAndDestinationsWithCapabilities().then(function() {
         // The system default destination should be used instead of the
         // most recent destination.
         assertEquals(
             'FooDevice',
             printPreview.destinationStore_.selectedDestination.id);
       });
     });
   });
 });