Clipboard Android - Store and Read Last Modified Time from Prefs

ui/base/clipboard/clipboard_android_unittest.cc

 // 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/clipboard/clipboard_android.h"
 
+#include <string>
+
 #include "base/android/context_utils.h"
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
+#include "base/time/time.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/clipboard/scoped_clipboard_writer.h"
 
 namespace ui {
 
 class ClipboardAndroidTest : public ::testing::Test {
  public:
   ~ClipboardAndroidTest() override {
     Clipboard::DestroyClipboardForCurrentThread();
   };
@@ skipping 58 matching lines @@
   // Make sure some text is available
   EXPECT_TRUE(clipboard().IsFormatAvailable(
       Clipboard::GetPlainTextWFormatType(), CLIPBOARD_TYPE_COPY_PASTE));
 
   // Make sure the text is what we inserted while simulating the other app
   std::string contents;
   clipboard().ReadAsciiText(CLIPBOARD_TYPE_COPY_PASTE, &contents);
   EXPECT_EQ(contents, new_value);
 }
 
+TEST_F(ClipboardAndroidTest, LastModifiedTimePersists) {
+  // Set up the pref system. ***
+  // 1. Create a TestingPrefServiceSimple (which is a PrefService)
+  //    and also use is registry() function.
+  // 2. Call ClipboardAndroid::RegisterPrefs()
+  // 3. Call ClipboardAndroid::SetLocalState()
+
+  base::Time test_start_time = base::Time::Now();
+  std::string url = "http://example.com/";
+  clipboard().WriteText(url.data(), url.length());
+  base::TimeDelta last_modified_time = clipboard().GetLastModifiedTime();
+  // It's possible the WriteText() took some time, so allow a little slop
+  // (5 seconds) in this comparison; don't check for equality.
+  EXPECT_GE(last_modified_time, test_start_time);
+  EXPECT_LE(last_modified_time,
+            test_start_time + base::TimeDelta::FromSeconds(5));
+
+  // *** Force writing the prefs / storing them, if necessary.
+
+  // Destroy the clipboard and make sure the information persists.  (It's be
+  // implicitly recreated when accessed.)
+  Clipboard::DestroyClipboardForCurrentThread();
+
+  // ***
+  // Check that the last modified time hasn't changed from the last time
+  // we read it.
+}
+
 }  // namespace ui
 
 #include "ui/base/clipboard/clipboard_test_template.h"