ShellUtil: Add generic methods to add/delete Windows file associations.

chrome/browser/file_associations_win_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 "chrome/browser/file_associations_win.h"
+
+#include "base/command_line.h"
+#include "base/files/file_path.h"
+#include "base/macros.h"
+#include "base/strings/utf_string_conversions.h"
+#include "base/test/test_reg_util_win.h"
+#include "base/win/registry.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+const char kTestProgid[] = "TestApp";
+const wchar_t kTestOpenCommand[] = L"C:\\test.exe";
+const char kTestFileTypeName[] = "Test File Type";
+const wchar_t kTestIconPath[] = L"D:\\test.ico";
+const char* kTestFileExtensions[] = {
+    "test1", "test2",
+};
+
+class FileAssociationsTest : public testing::Test {
+ public:
+  FileAssociationsTest() {}
+
+ protected:
+  virtual void SetUp() OVERRIDE {
+    registry_overrides_.OverrideRegistry(HKEY_CURRENT_USER, base::string16());
+
+    // .test2 files already have a default application.
+    base::win::RegKey key;
+    ASSERT_EQ(
+        ERROR_SUCCESS,
+        key.Create(
+            HKEY_CURRENT_USER, L"Software\\Classes\\.test2", KEY_ALL_ACCESS));
+    EXPECT_EQ(ERROR_SUCCESS, key.WriteValue(L"", L"SomeOtherApp"));
+  }
+
+  static base::CommandLine OpenCommand() {
+    base::FilePath open_command_path(kTestOpenCommand);
+    return base::CommandLine(open_command_path);
+  }
+
+  static std::set<std::string> FileExtensions() {
+    std::set<std::string> file_extensions;
+    for (size_t i = 0; i < arraysize(kTestFileExtensions); ++i)
+      file_extensions.insert(kTestFileExtensions[i]);
+    return file_extensions;
+  }
+
+ private:
+  registry_util::RegistryOverrideManager registry_overrides_;
+
+  DISALLOW_COPY_AND_ASSIGN(FileAssociationsTest);
+};
+
+TEST_F(FileAssociationsTest, AddWindowsFileAssociations) {
+  // Create file associations.
+  EXPECT_TRUE(AddWindowsFileAssociations(kTestProgid,
+                                         OpenCommand(),
+                                         kTestFileTypeName,
+                                         base::FilePath(kTestIconPath),
+                                         FileExtensions()));
+
+  // Ensure that the registry keys have been correctly set.
+  base::win::RegKey key;
+  std::wstring value;
+  ASSERT_EQ(
+      ERROR_SUCCESS,
+      key.Open(HKEY_CURRENT_USER, L"Software\\Classes\\TestApp", KEY_READ));

[gab, 2014/09/18 01:16:15]

Build these test strings from the constants (mostly to make this more readable
as an expectation following the call using those constants, but also more
reliable).

[Matt Giuca, 2014/09/30 10:21:12]

Now it's my turn to quote TOTT to you :)

Episode 338: "Don't Put Logic in Tests" essentially gives this exact case as an
example. We don't want bugs in the test such as missing or doubling up slashes.
If I build the strings from the constants, my test would have the exact same
logic as the code it's testing, and if that logic builds the wrong string, the
test will still pass.

It's best to fully write out the paths in the test even if it means duplicating
them a lot.

[gab, 2014/10/01 14:31:11]

Fair enough ;-)!

+  EXPECT_EQ(ERROR_SUCCESS, key.ReadValue(L"", &value));
+  EXPECT_EQ(L"Test File Type", value);

[gab, 2014/09/18 01:16:15]

Same here/below, use constants.

+  ASSERT_EQ(ERROR_SUCCESS,
+            key.Open(HKEY_CURRENT_USER,
+                     L"Software\\Classes\\TestApp\\DefaultIcon",
+                     KEY_READ));
+  EXPECT_EQ(ERROR_SUCCESS, key.ReadValue(L"", &value));
+  EXPECT_EQ(L"D:\\test.ico,0", value);
+  ASSERT_EQ(ERROR_SUCCESS,
+            key.Open(HKEY_CURRENT_USER,
+                     L"Software\\Classes\\TestApp\\shell\\open\\command",
+                     KEY_READ));
+  EXPECT_EQ(ERROR_SUCCESS, key.ReadValue(L"", &value));
+  EXPECT_EQ(L"\"C:\\test.exe\"", value);
+
+  // .test1 should be default-associated with our test app.
+  ASSERT_EQ(
+      ERROR_SUCCESS,
+      key.Open(HKEY_CURRENT_USER, L"Software\\Classes\\.test1", KEY_READ));
+  EXPECT_EQ(ERROR_SUCCESS, key.ReadValue(L"", &value));
+  EXPECT_EQ(L"TestApp", value);
+  ASSERT_EQ(ERROR_SUCCESS,
+            key.Open(HKEY_CURRENT_USER,
+                     L"Software\\Classes\\.test1\\OpenWithProgids",
+                     KEY_READ));
+  EXPECT_TRUE(key.HasValue(L"TestApp"));
+  EXPECT_EQ(ERROR_SUCCESS, key.ReadValue(L"TestApp", &value));
+  EXPECT_EQ(L"", value);
+
+  // .test2 should still be associated with the other app (should not have been
+  // overridden). But it should have our app in its Open With list.
+  ASSERT_EQ(
+      ERROR_SUCCESS,
+      key.Open(HKEY_CURRENT_USER, L"Software\\Classes\\.test2", KEY_READ));
+  EXPECT_EQ(ERROR_SUCCESS, key.ReadValue(L"", &value));
+  EXPECT_EQ(L"SomeOtherApp", value);
+  ASSERT_EQ(ERROR_SUCCESS,
+            key.Open(HKEY_CURRENT_USER,
+                     L"Software\\Classes\\.test2\\OpenWithProgids",
+                     KEY_READ));
+  EXPECT_TRUE(key.HasValue(L"TestApp"));
+  EXPECT_EQ(ERROR_SUCCESS, key.ReadValue(L"TestApp", &value));
+  EXPECT_EQ(L"", value);
+}
+
+TEST_F(FileAssociationsTest, DeleteWindowsFileAssociations) {
+  // Create file associations.
+  EXPECT_TRUE(AddWindowsFileAssociations(kTestProgid,
+                                         OpenCommand(),
+                                         kTestFileTypeName,
+                                         base::FilePath(kTestIconPath),
+                                         FileExtensions()));
+
+  // Delete them again.

[gab, 2014/09/18 01:16:15]

What do you mean by "again"; this is the first time you're deleting them
AFAICT..?

[Matt Giuca, 2014/09/30 10:21:12]

I guess I meant "again" in the "All the king's horses and all the king's men
couldn't put Humpty together again" sense --- to revert back to a previous
state, as opposed to doing an action a second time.

I'll reword it...

+  EXPECT_TRUE(DeleteWindowsFileAssociations(kTestProgid));
+
+  // The class key should have been completely deleted.
+  base::win::RegKey key;
+  std::wstring value;
+  ASSERT_NE(
+      ERROR_SUCCESS,
+      key.Open(HKEY_CURRENT_USER, L"Software\\Classes\\TestApp", KEY_READ));
+
+  // We don't need to delete the associations with the particular extensions
+  // (Windows will ignore those). However, we must ensure that .test2 is still
+  // associated with the other app.
+  ASSERT_EQ(
+      ERROR_SUCCESS,
+      key.Open(HKEY_CURRENT_USER, L"Software\\Classes\\.test2", KEY_READ));
+  EXPECT_EQ(ERROR_SUCCESS, key.ReadValue(L"", &value));
+  EXPECT_EQ(L"SomeOtherApp", value);
+}
+
+}  // namespace