Added regression test for event listeners memory leak.

webkit/tools/test_shell/listener_leak_test.cc

Index: webkit/tools/test_shell/listener_leak_test.cc
diff --git a/webkit/tools/test_shell/listener_leak_test.cc b/webkit/tools/test_shell/listener_leak_test.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7064f77930b21da2ff277f035b62a95573d91228
--- /dev/null
+++ b/webkit/tools/test_shell/listener_leak_test.cc
@@ -0,0 +1,78 @@
+// Copyright (c) 2009 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 "base/file_path.h"
+#include "base/file_util.h"
+#include "base/path_service.h"
+#include "base/string_util.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "v8/include/v8.h"
+#include "webkit/glue/webkit_glue.h"
+#include "webkit/tools/test_shell/test_shell.h"
+#include "webkit/tools/test_shell/test_shell_test.h"
+
+static const char kHeapSampleBegin[] = "heap-sample-begin,";
+static const char kHeapObjectLogEntryPrefix[] = "\nheap-js-cons-item,";
+static const char kHeapObjectLogEntrySuffix[] = ",";
+
+class ListenerLeakTest : public TestShellTest {
+};
+
+static std::string GetV8Log(int skip) {
+  std::string v8_log;
+  char buf[1024];
+  int read_size;
+  do {
+    read_size = v8::V8::GetLogLines(skip + static_cast<int>(v8_log.size()),
+                                    buf, sizeof(buf));
+    v8_log.append(buf, read_size);
+  } while (read_size > 0);
+  return v8_log;
+}
+
+static int GetNumObjects(int log_skip, const std::string& constructor) {
+  std::string v8_log = GetV8Log(log_skip);
+  size_t sample_begin = v8_log.rfind(kHeapSampleBegin);
+  CHECK(sample_begin != std::string::npos);
+  std::string log_entry =
+      kHeapObjectLogEntryPrefix + constructor + kHeapObjectLogEntrySuffix;
+  size_t i = v8_log.find(log_entry, sample_begin);
+  if (i == std::string::npos) return 0;
+  i += log_entry.size();
+  size_t j = v8_log.find(",", i);
+  CHECK(j != std::string::npos);
+  int num_objects;
+  CHECK(StringToInt(v8_log.substr(i, j - i), &num_objects));
+  return num_objects;
+}
+
+// This test tries to create a reference cycle between node and its listener.
+// See http://crbug/17400.
+TEST_F(ListenerLeakTest, ReferenceCycle) {
+  const int log_skip = static_cast<int>(GetV8Log(0).size());
+  FilePath listener_file;
+  ASSERT_TRUE(PathService::Get(base::DIR_SOURCE_ROOT, &listener_file));
+  listener_file = listener_file.Append(FILE_PATH_LITERAL("webkit"))
+      .Append(FILE_PATH_LITERAL("data"))
+      .Append(FILE_PATH_LITERAL("listener"))
+      .Append(FILE_PATH_LITERAL("listener_leak1.html"));
+  test_shell_->LoadURL(listener_file.ToWStringHack().c_str());
+  test_shell_->WaitTestFinished();
+  ASSERT_EQ(0, GetNumObjects(log_skip, "EventListenerLeakTestObject1"));
+}
+
+// This test sets node onclick many times to expose a possible memory
+// leak where all listeners get referenced by the node.
+TEST_F(ListenerLeakTest, HiddenReferences) {
+  const int log_skip = static_cast<int>(GetV8Log(0).size());
+  FilePath listener_file;
+  ASSERT_TRUE(PathService::Get(base::DIR_SOURCE_ROOT, &listener_file));
+  listener_file = listener_file.Append(FILE_PATH_LITERAL("webkit"))
+      .Append(FILE_PATH_LITERAL("data"))
+      .Append(FILE_PATH_LITERAL("listener"))
+      .Append(FILE_PATH_LITERAL("listener_leak2.html"));
+  test_shell_->LoadURL(listener_file.ToWStringHack().c_str());
+  test_shell_->WaitTestFinished();
+  ASSERT_EQ(1, GetNumObjects(log_skip, "EventListenerLeakTestObject2"));
+}