Files app: Select My files when there are no volumes

Make Files app select "My files" when there are no available volumes,
this to allow Files app to behave properly when volumes subsequently
become available.

Change DirectoryModel.onVolumeInfoListUpdated_ method to check for
non-null |displayRoot| before trying to change to |displayRoot|. This
fixes the error "Cannot read property 'getParent' of null" when Drive
volume becomes available before Downloads volume, which is the default
volume/root.

Change FakeDriveFs to unbind the two mojo bindings if they're bound, so
DriveFsTestVolume can re-mount itself.

Test: browser_tests --gtest_filter="*/fileDisplayWithoutVolumesThenMount*"
Bug: 893161, 884967
Change-Id: Ic813b25261530495c11c9f641a92f6e07f883702
Reviewed-on: https://chromium-review.googlesource.com/c/1272418Reviewed-by: Noel Gordon <noel@chromium.org>
Reviewed-by: Sam McNally <sammc@chromium.org>
Commit-Queue: Luciano Pacheco <lucmult@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599026}

chrome/browser/chromeos/file_manager/file_manager_browsertest.cc

@@ -197,6 +197,9 @@ WRAPPED_INSTANTIATE_TEST_CASE_P(
         TestCase("fileSearch"),
         TestCase("fileDisplayWithoutDownloadsVolume"),
         TestCase("fileDisplayWithoutVolumes"),
+        TestCase("fileDisplayWithoutVolumesThenMountDownloads"),
+        TestCase("fileDisplayWithoutVolumesThenMountDrive"),
+        TestCase("fileDisplayWithoutVolumesThenMountDrive").EnableDriveFs(),
         TestCase("fileSearchCaseInsensitive"),
         TestCase("fileSearchNotFound")));
 

chrome/browser/chromeos/file_manager/file_manager_browsertest_base.cc

@@ -828,6 +828,18 @@ class DriveTestVolume : public TestVolume {
     return integration_service_;
   }
 
+  bool Mount(Profile* profile) {
+    if (profile != profile_)
+      return false;
+
+    if (!integration_service_)
+      return false;
+
+    integration_service_->SetEnabled(true);
+    CreateDriveFsConnectionDelegate();
+    return true;
+  }
+
   void Unmount() { integration_service_->SetEnabled(false); }
 
  private:
@@ -1355,6 +1367,11 @@ void FileManagerBrowserTestBase::OnCommand(const std::string& name,
     return;
   }
 
+  if (name == "mountDrive") {
+    ASSERT_TRUE(drive_volume_->Mount(profile()));
+    return;
+  }
+
   if (name == "mountDownloads") {
     ASSERT_TRUE(local_volume_->Mount(profile()));
     return;

chromeos/components/drivefs/fake_drivefs.cc

@@ -256,6 +256,8 @@ void FakeDriveFs::RegisterMountingForAccountId(
 std::unique_ptr<drivefs::DriveFsHost::MojoConnectionDelegate>
 FakeDriveFs::CreateConnectionDelegate() {
   drivefs::mojom::DriveFsBootstrapPtrInfo bootstrap;
+  if (bootstrap_binding_.is_bound())
+    bootstrap_binding_.Unbind();
   bootstrap_binding_.Bind(mojo::MakeRequest(&bootstrap));
   pending_delegate_request_ = mojo::MakeRequest(&delegate_);
   delegate_->OnMounted();
@@ -287,6 +289,8 @@ void FakeDriveFs::Init(drivefs::mojom::DriveFsConfigurationPtr config,
                        drivefs::mojom::DriveFsDelegatePtr delegate) {
   mojo::FuseInterface(std::move(pending_delegate_request_),
                       delegate.PassInterface());
+  if (binding_.is_bound())
+    binding_.Unbind();
   binding_.Bind(std::move(drive_fs_request));
 }
 

ui/file_manager/file_manager/foreground/js/directory_model.js

@@ -1197,7 +1197,8 @@ DirectoryModel.prototype.onVolumeInfoListUpdated_ = function(event) {
   var entry = this.getCurrentDirEntry();
   if (entry && !this.volumeManager_.getVolumeInfo(entry)) {
     this.volumeManager_.getDefaultDisplayRoot(function(displayRoot) {
-      this.changeDirectoryEntry(displayRoot);
+      if (displayRoot)
+        this.changeDirectoryEntry(displayRoot);
     }.bind(this));
   }
 

ui/file_manager/file_manager/foreground/js/file_manager.js

@@ -1426,6 +1426,18 @@ FileManager.prototype = /** @struct */ {
           }.bind(this));
     }.bind(this));
 
+    queue.run((callback) => {
+      // If there is target to be selected, just move to next step.
+      if (nextCurrentDirEntry) {
+        callback();
+        return;
+      }
+
+      // Try to select MyFiles if anything else has failed.
+      nextCurrentDirEntry = this.directoryTree.dataModel.myFilesModel_.entry;
+      callback();
+    });
+
     // Finalize.
     queue.run(function(callback) {
       // Check directory change.

ui/file_manager/integration_tests/file_manager/file_display.js

@@ -392,3 +392,101 @@ testcase.fileDisplayWithoutVolumes = function() {
     },
   ]);
 };
+
+/**
+ * Tests Files app opening without errors when there are no volumes at all and
+ * then mounting Downloads volume which should appear and be able to display its
+ * files.
+ */
+testcase.fileDisplayWithoutVolumesThenMountDownloads = function() {
+  let appId;
+
+  StepsRunner.run([
+    // Unmount all default volumes.
+    function() {
+      sendTestMessage({name: 'unmountAllVolumes'}).then(this.next);
+    },
+    // Open Files app without specifying the initial directory/root.
+    function() {
+      openNewWindow(null, null, this.next);
+    },
+    // Wait for Files app to finish loading.
+    function(result) {
+      chrome.test.assertTrue(!!result, 'failed to open new window');
+      appId = result;
+      remoteCall.waitFor('isFileManagerLoaded', appId, true).then(this.next);
+    },
+    // Remount Downloads.
+    function() {
+      sendTestMessage({name: 'mountDownloads'}).then(this.next);
+    },
+    // Add an entry to Downloads.
+    function() {
+      addEntries(['local'], [ENTRIES.newlyAdded], this.next);
+    },
+    // Because Downloads is the default volume it will be automatically
+    // selected, so let's wait for its entry to appear.
+    function() {
+      remoteCall.waitForFiles(appId, [ENTRIES.newlyAdded.getExpectedRow()])
+          .then(this.next);
+    },
+    function() {
+      checkIfNoErrorsOccured(this.next);
+    },
+  ]);
+};
+
+/**
+ * Tests Files app opening without errors when there are no volumes at all and
+ * then mounting Drive volume which should appear and be able to display its
+ * files.
+ */
+testcase.fileDisplayWithoutVolumesThenMountDrive = function() {
+  let appId;
+  const driveTreeItem = '#directory-tree [entry-label="Google Drive"]';
+
+  StepsRunner.run([
+    // Unmount all default volumes.
+    function() {
+      sendTestMessage({name: 'unmountAllVolumes'}).then(this.next);
+    },
+    // Open Files app without specifying the initial directory/root.
+    function() {
+      openNewWindow(null, null, this.next);
+    },
+    // Wait for Files app to finish loading.
+    function(result) {
+      chrome.test.assertTrue(!!result, 'failed to open new window');
+      appId = result;
+      remoteCall.waitFor('isFileManagerLoaded', appId, true).then(this.next);
+    },
+    // Remount Drive.
+    function() {
+      sendTestMessage({name: 'mountDrive'}).then(this.next);
+    },
+    // Add an entry to Drive.
+    function() {
+      addEntries(['drive'], [ENTRIES.newlyAdded], this.next);
+    },
+    // Wait "Google Drive" to show up in the directory tree.
+    function() {
+      remoteCall.waitForElement(appId, driveTreeItem).then(this.next);
+    },
+    // Select "My Drive" to display its content.
+    function() {
+      const isDriveSubVolume = true;
+      remoteCall
+          .callRemoteTestUtil(
+              'selectInDirectoryTree', appId, [driveTreeItem, isDriveSubVolume])
+          .then(this.next);
+    },
+    // Wait for "My Drive" files to display in the file list.
+    function() {
+      remoteCall.waitForFiles(appId, [ENTRIES.newlyAdded.getExpectedRow()])
+          .then(this.next);
+    },
+    function() {
+      checkIfNoErrorsOccured(this.next);
+    },
+  ]);
+};