[NativeFS] Introduce a browser test for native file system drag and drop

Introduces a browser test that implements end-to-end testing of
the DataTransferItem.getAsFileSystemHandle() method. It contains two
tests: one for dropped files and one for dropped directories.

Bug: 1080811
Change-Id: Ie64096539a732c0a2d101ca98bf9e86fcc9190ee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2339945
Commit-Queue: Hazim Mohamed <hazimmohamed@google.com>
Reviewed-by: Marijn Kruisselbrink <mek@chromium.org>
Reviewed-by: Darwin Huang <huangdarwin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#797986}

content/browser/native_file_system/native_file_system_drag_drop_browsertest.cc

+// Copyright 2020 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.
+
+#include <string>
+
+#include "base/files/file_util.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/test/scoped_feature_list.h"
+#include "content/browser/native_file_system/native_file_system_manager_impl.h"
+#include "content/browser/web_contents/web_contents_impl.h"
+#include "content/public/common/drop_data.h"
+#include "content/public/test/browser_test.h"
+#include "content/public/test/browser_test_utils.h"
+#include "content/public/test/content_browser_test.h"
+#include "content/public/test/content_browser_test_utils.h"
+#include "content/shell/browser/shell.h"
+#include "net/test/embedded_test_server/embedded_test_server.h"
+#include "ui/base/dragdrop/file_info/file_info.h"
+#include "ui/gfx/geometry/point_f.h"
+
+namespace content {
+
+// End-to-end tests for Native File System drag and drop, or more specifically,
+// DataTransferItem's getAsFileSystemHandle method.
+
+class NativeFileSystemDragDropBrowserTest : public ContentBrowserTest {
+ public:
+  void SetUp() override {
+    ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
+    scoped_feature_list_.InitAndEnableFeature(
+        blink::features::kNativeFileSystemAPI);
+    ASSERT_TRUE(embedded_test_server()->Start());
+    ContentBrowserTest::SetUp();
+  }
+
+  void SetUpCommandLine(base::CommandLine* command_line) override {
+    // Enable experimental web platform features to enable write access.
+    command_line->AppendSwitch(
+        switches::kEnableExperimentalWebPlatformFeatures);
+    // TODO(hazimmohamed): Remove this switch when NativeFileSystemDragAndDrop
+    // becomes part of kEnableExperimentalWebPlatformFeatures.
+    command_line->AppendSwitchASCII(switches::kEnableBlinkFeatures,
+                                    "NativeFileSystemDragAndDrop");
+  }
+
+  void TearDown() override {
+    ContentBrowserTest::TearDown();
+    ASSERT_TRUE(temp_dir_.Delete());
+  }
+
+  base::FilePath CreateTestFileInDirectory(const base::FilePath& directory_path,
+                                           const std::string& contents) {
+    base::ScopedAllowBlockingForTesting allow_blocking;
+    base::FilePath result;
+    EXPECT_TRUE(base::CreateTemporaryFileInDir(directory_path, &result));
+    EXPECT_TRUE(base::WriteFile(result, contents));
+    return result;
+  }
+
+  base::FilePath CreateTestDir() {
+    base::ScopedAllowBlockingForTesting allow_blocking;
+    base::FilePath result;
+    EXPECT_TRUE(base::CreateTemporaryDirInDir(
+        temp_dir_.GetPath(), FILE_PATH_LITERAL("test"), &result));
+    return result;
+  }
+
+  RenderWidgetHostImpl* GetRenderWidgetHostImplForMainFrame() {
+    WebContentsImpl* web_contents_impl =
+        static_cast<WebContentsImpl*>(shell()->web_contents());
+    return web_contents_impl->GetMainFrame()->GetRenderWidgetHost();
+  }
+
+ protected:
+  base::test::ScopedFeatureList scoped_feature_list_;
+  base::ScopedTempDir temp_dir_;
+};
+
+IN_PROC_BROWSER_TEST_F(NativeFileSystemDragDropBrowserTest, DropFile) {
+  // Get the RenderWidgetHostImpl for the main (and only) frame.
+  RenderWidgetHostImpl* render_widget_host_impl =
+      GetRenderWidgetHostImplForMainFrame();
+  DCHECK(render_widget_host_impl);
+
+  // Prepare the window for dragging and dropping.
+  ASSERT_TRUE(
+      NavigateToURL(shell(), embedded_test_server()->GetURL("/title1.html")));
+
+  // Prevent defaults of drag operations and create a promise that will resolve
+  // on call to window.ondrop with the text from a dropped file. This text is
+  // retrieved using the NativeFileSystem getAsFileSystemHandle function. The
+  // promise will reject if zero/multiples items are dropped or if the item is
+  // not a file.
+  ASSERT_TRUE(
+      ExecJs(shell(),
+             "window.ondragenter = (e) => { e.preventDefault() };"
+             "window.ondragover = (e) => { e.preventDefault() };"
+             "var p = new Promise((resolve, reject) => {"
+             "  window.ondrop = async (event) => {"
+             "    event.preventDefault();"
+             "    if (event.dataTransfer.items.length !== 1) {"
+             "      reject('There were ' + event.dataTransfer.items.length"
+             "              + ' dropped items. Expected 1.');"
+             "    }"
+             "    if (event.dataTransfer.items[0].kind != 'file') {"
+             "      reject('The drag item was of kind: ' +"
+             "              event.dataTransfer.items[0].kind + '. Expected"
+             "              file.');"
+             "    }"
+             "    const fileItem = event.dataTransfer.items[0];"
+             "    const fileHandle = await fileItem.getAsFileSystemHandle();"
+             "    if (fileHandle.kind !== 'file') {"
+             "       reject('The dragged item was a directory, expected it to"
+             "               be a file.');"
+             "    }"
+             "    const file = await fileHandle.getFile();"
+             "    const text = await file.text();"
+             "    resolve(text);"
+             "  }"
+             "});"));
+
+  // Create a test file with contents `test_contents` to drop on the webpage.
+  std::string test_contents = "Deleted code is debugged code.";
+  base::FilePath test_file_path =
+      CreateTestFileInDirectory(temp_dir_.GetPath(), test_contents);
+
+  // Get the points corresponding to the center of the browser window in both
+  // screen coordinates and window coordinates.
+  const gfx::Rect window_in_screen_coords =
+      render_widget_host_impl->GetView()->GetBoundsInRootWindow();
+  const gfx::PointF screen_point =
+      gfx::PointF(window_in_screen_coords.CenterPoint());
+  const gfx::PointF client_point =
+      gfx::PointF(window_in_screen_coords.width() / 2,
+                  window_in_screen_coords.height() / 2);
+
+  // Drop the test file.
+  DropData drop_data;
+  drop_data.filenames.emplace_back(
+      ui::FileInfo(test_file_path, test_file_path.BaseName()));
+  render_widget_host_impl->FilterDropData(&drop_data);
+  render_widget_host_impl->DragTargetDragEnter(
+      drop_data, client_point, screen_point,
+      blink::WebDragOperationsMask::kWebDragOperationEvery,
+      /*key_modifiers=*/0);
+  render_widget_host_impl->DragTargetDragOver(
+      client_point, screen_point,
+      blink::WebDragOperationsMask::kWebDragOperationEvery,
+      /*key_modifiers=*/0);
+  render_widget_host_impl->DragTargetDrop(drop_data, client_point, screen_point,
+                                          /*key_modifiers=*/0);
+
+  // Expect the promise to resolve with `test_contents`.
+  EXPECT_EQ(test_contents, EvalJs(shell(), "p"));
+}
+
+IN_PROC_BROWSER_TEST_F(NativeFileSystemDragDropBrowserTest, DropDirectory) {
+  // Get the RenderWidgetHostImpl for the main (and only) frame.
+  RenderWidgetHostImpl* render_widget_host_impl =
+      GetRenderWidgetHostImplForMainFrame();
+  DCHECK(render_widget_host_impl);
+
+  // Prepare the window for dragging and dropping.
+  ASSERT_TRUE(
+      NavigateToURL(shell(), embedded_test_server()->GetURL("/title1.html")));
+
+  // Prevent defaults of drag operations and create a promise that will resolve
+  // with the name of the child directory of the dropped directory. The promise
+  // rejects if there are zero/multiple items dropped or if the dropped item is
+  // directory. The promise will also reject if there are zero/multiple items
+  // inside the dropped directory.
+  ASSERT_TRUE(
+      ExecJs(shell(),
+             "window.ondragenter = (e) => { e.preventDefault() };"
+             "window.ondragover = (e) => { e.preventDefault() };"
+             "var p = new Promise((resolve, reject) => {"
+             "  window.ondrop = async (dragEvent) => {"
+             "    dragEvent.preventDefault();"
+             "    if (dragEvent.dataTransfer.items.length !== 1) {"
+             "      reject('There were ' + dragEvent.dataTransfer.items.length"
+             "              + ' dropped items. Expected 1.');"
+             "    }"
+             "    if (dragEvent.dataTransfer.items[0].kind != 'file') {"
+             "      reject('The drag item was of kind: ' +"
+             "              dragEvent.dataTransfer.items[0].kind + '. Expected"
+             "              file.');"
+             "    }"
+             "    const fileItem = dragEvent.dataTransfer.items[0];"
+             "    directoryHandle = await fileItem.getAsFileSystemHandle();"
+             "    if (directoryHandle.kind !== 'directory') {"
+             "       reject('The dragged item was a file, expected it to be a "
+             "               directory.');"
+             "    }"
+             "    let directoryContents = [];"
+             "    for await (let fileName of directoryHandle.keys()) {"
+             "       directoryContents.push(fileName);"
+             "     };"
+             "     if (directoryContents.length !== 1) {"
+             "       reject('There were ', directoryContents.length, ' files "
+             "               in the dropped directory. Expected 1.');"
+             "     }"
+             "     resolve(directoryContents.pop());"
+             "   }"
+             "});"));
+
+  // Create a directory and create a file inside the directory.
+  const base::FilePath test_dir_path = CreateTestDir();
+  std::string contents = "Irrelevant contents.";
+  const base::FilePath file_inside_dir =
+      CreateTestFileInDirectory(test_dir_path, contents);
+
+  // Get the points corresponding to the center of the browser window in both
+  // screen coordinates and window coordinates.
+  const gfx::Rect window_in_screen_coords =
+      render_widget_host_impl->GetView()->GetBoundsInRootWindow();
+  const gfx::PointF screen_point =
+      gfx::PointF(window_in_screen_coords.CenterPoint());
+  const gfx::PointF client_point =
+      gfx::PointF(window_in_screen_coords.width() / 2,
+                  window_in_screen_coords.height() / 2);
+
+  // Drop the test file.
+  DropData drop_data;
+  drop_data.filenames.emplace_back(
+      ui::FileInfo(test_dir_path, test_dir_path.BaseName()));
+  render_widget_host_impl->FilterDropData(&drop_data);
+  render_widget_host_impl->DragTargetDragEnter(
+      drop_data, client_point, screen_point,
+      blink::WebDragOperationsMask::kWebDragOperationEvery,
+      /*key_modifiers=*/0);
+  render_widget_host_impl->DragTargetDragOver(
+      client_point, screen_point,
+      blink::WebDragOperationsMask::kWebDragOperationEvery,
+      /*key_modifiers=*/0);
+  render_widget_host_impl->DragTargetDrop(drop_data, client_point, screen_point,
+                                          /*key_modifiers=*/0);
+
+  // Wait promise to resolve and expect the directory to have child with name
+  // matching the base name of `file_inside_dir`.
+  EXPECT_EQ(file_inside_dir.BaseName().AsUTF8Unsafe(), EvalJs(shell(), "p"));
+}
+}  // namespace content
\ No newline at end of file

content/test/BUILD.gn

@@ -1010,6 +1010,7 @@ test("content_browsertests") {
     "../browser/message_port_provider_browsertest.cc",
     "../browser/mojo_sandbox_browsertest.cc",
     "../browser/native_file_system/file_system_chooser_browsertest.cc",
+    "../browser/native_file_system/native_file_system_drag_drop_browsertest.cc",
     "../browser/native_file_system/native_file_system_file_writer_impl_browsertest.cc",
     "../browser/navigation_browsertest.cc",
     "../browser/navigation_mhtml_browsertest.cc",