Process SelectionRequestor::PerformBlockingConvertSelection() requests one at a time

ui/base/x/selection_requestor_unittest.cc

Index: ui/base/x/selection_requestor_unittest.cc
diff --git a/ui/base/x/selection_requestor_unittest.cc b/ui/base/x/selection_requestor_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..fe6ee42e132af365b5e99de5e284a0d7a74078e9
--- /dev/null
+++ b/ui/base/x/selection_requestor_unittest.cc
@@ -0,0 +1,165 @@
+// Copyright 2014 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 "ui/base/x/selection_requestor.h"
+
+#include "base/memory/ref_counted_memory.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/message_loop/message_loop.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "ui/base/x/selection_utils.h"
+#include "ui/base/x/x11_util.h"
+#include "ui/events/platform/platform_event_source.h"
+#include "ui/gfx/x/x11_atom_cache.h"
+#include "ui/gfx/x/x11_types.h"
+
+#include <X11/Xlib.h>
+
+namespace ui {
+
+namespace {
+
+const char* kAtomsToCache[] = {
+    "STRING",
+    NULL
+};
+
+}  // namespace
+
+class SelectionRequestorTest : public testing::Test {
+ public:
+  SelectionRequestorTest()
+      : x_display_(gfx::GetXDisplay()),
+        x_window_(None),
+        atom_cache_(gfx::GetXDisplay(), kAtomsToCache) {
+    atom_cache_.allow_uncached_atoms();
+  }
+
+  virtual ~SelectionRequestorTest() {
+  }
+
+  // Responds to the SelectionRequestor's XConvertSelection() request by
+  // - Setting the property passed into the XConvertSelection() request to
+  //   |value|.
+  // - Sending a SelectionNotify event.
+  void SendSelectionNotify(XAtom selection,
+                           XAtom target,
+                           const std::string& value) {
+    ui::SetStringProperty(x_window_,
+                          requestor_->x_property_,
+                          atom_cache_.GetAtom("STRING"),
+                          value);
+
+    XEvent xev;
+    xev.type = SelectionNotify;
+    xev.xselection.serial = 0u;
+    xev.xselection.display = x_display_;
+    xev.xselection.requestor = x_window_;
+    xev.xselection.selection = selection;
+    xev.xselection.target = target;
+    xev.xselection.property = requestor_->x_property_;
+    xev.xselection.time = CurrentTime;
+    xev.xselection.type = SelectionNotify;
+    requestor_->OnSelectionNotify(xev);
+  }
+
+ protected:
+  virtual void SetUp() OVERRIDE {
+    // Make X11 synchronous for our display connection.
+    XSynchronize(x_display_, True);
+
+    // Create a window for the selection requestor to use.
+    x_window_ = XCreateWindow(x_display_,
+                              DefaultRootWindow(x_display_),
+                              0, 0, 10, 10,    // x, y, width, height
+                              0,               // border width
+                              CopyFromParent,  // depth
+                              InputOnly,
+                              CopyFromParent,  // visual
+                              0,
+                              NULL);
+
+    event_source_ = ui::PlatformEventSource::CreateDefault();
+    CHECK(ui::PlatformEventSource::GetInstance());
+    requestor_.reset(new SelectionRequestor(x_display_, x_window_, NULL));
+  }
+
+  virtual void TearDown() OVERRIDE {
+    requestor_.reset();
+    event_source_.reset();
+    XDestroyWindow(x_display_, x_window_);
+    XSynchronize(x_display_, False);
+  }
+
+  Display* x_display_;
+
+  // |requestor_|'s window.
+  XID x_window_;
+
+  scoped_ptr<ui::PlatformEventSource> event_source_;
+  scoped_ptr<SelectionRequestor> requestor_;
+
+  base::MessageLoopForUI message_loop_;
+  X11AtomCache atom_cache_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(SelectionRequestorTest);
+};
+
+namespace {
+
+// Converts |selection| to |target| and checks the returned values.
+void PerformBlockingConvertSelection(SelectionRequestor* requestor,
+                                     X11AtomCache* atom_cache,
+                                     XAtom selection,
+                                     XAtom target,
+                                     const std::string& expected_data) {
+  scoped_refptr<base::RefCountedMemory> out_data;
+  size_t out_data_items = 0u;
+  XAtom out_type = None;
+  EXPECT_TRUE(requestor->PerformBlockingConvertSelection(
+      selection, target, &out_data, &out_data_items, &out_type));
+  EXPECT_EQ(expected_data, ui::RefCountedMemoryToString(out_data));
+  EXPECT_EQ(expected_data.size(), out_data_items);
+  EXPECT_EQ(atom_cache->GetAtom("STRING"), out_type);
+}
+
+}  // namespace
+
+// Test that SelectionRequestor correctly handles receiving a request while it
+// is processing another request.
+TEST_F(SelectionRequestorTest, NestedRequests) {
+  // Assume that |selection| will have no owner. If there is an owner, the owner
+  // will set the property passed into the XConvertSelection() request which is
+  // undesirable.
+  XAtom selection = atom_cache_.GetAtom("FAKE_SELECTION");
+
+  XAtom target1 = atom_cache_.GetAtom("TARGET1");
+  XAtom target2 = atom_cache_.GetAtom("TARGET2");
+
+  base::MessageLoopForUI* loop = base::MessageLoopForUI::current();
+  loop->PostTask(FROM_HERE,
+                 base::Bind(&PerformBlockingConvertSelection,
+                            base::Unretained(requestor_.get()),
+                            base::Unretained(&atom_cache_),
+                            selection,
+                            target2,
+                            "Data2"));
+  loop->PostTask(FROM_HERE,
+                 base::Bind(&SelectionRequestorTest::SendSelectionNotify,
+                            base::Unretained(this),
+                            selection,
+                            target1,
+                            "Data1"));
+  loop->PostTask(FROM_HERE,
+                 base::Bind(&SelectionRequestorTest::SendSelectionNotify,
+                            base::Unretained(this),
+                            selection,
+                            target2,
+                            "Data2"));
+  PerformBlockingConvertSelection(
+      requestor_.get(), &atom_cache_, selection, target1, "Data1");
+}
+
+}  // namespace ui