Remove JsonPrefStore pruning of empty values on write.

base/prefs/json_pref_store_unittest.cc

Index: base/prefs/json_pref_store_unittest.cc
diff --git a/base/prefs/json_pref_store_unittest.cc b/base/prefs/json_pref_store_unittest.cc
index 34e1b8a9ede63dcf76b4b5edeaa242c180f1bc8b..a933ca7e8d69184b037fd0469a0b8857472ebd82 100644
--- a/base/prefs/json_pref_store_unittest.cc
+++ b/base/prefs/json_pref_store_unittest.cc
@@ -216,6 +216,25 @@ TEST_F(JsonPrefStoreTest, BasicAsync) {
       pref_store.get(), input_file, data_dir_.AppendASCII("write.golden.json"));
 }
 
+TEST_F(JsonPrefStoreTest, PreserveEmptyValues) {
+  FilePath pref_file = temp_dir_.path().AppendASCII("empty_values.json");
+
+  // Test that the persistent value can be loaded.

[Mattias Nissler (ping if slow), 2013/11/22 08:03:38]

I think this comment is stale.

[gab, 2013/11/22 23:24:21]

Removed.

+  scoped_refptr<JsonPrefStore> pref_store =
+      new JsonPrefStore(pref_file, message_loop_.message_loop_proxy());

[Mattias Nissler (ping if slow), 2013/11/22 08:03:38]

Looks like there's a merge problem here, the original test set some empty values
in |pref_store|. In fact, I believe what's here now should fail in lines
232-235.

[gab, 2013/11/22 23:24:21]

Oops, merge problem indeed, fixed to be as in
https://codereview.chromium.org/12092021/diff/4001/base/prefs/json_pref_store...

I moved it up one block in this CL to have a clearer diff (the diff tool
otherwise tries to make a reasonable diff from the test being deleted to the new
test which aren't really the same at all...).

+  // Reload.
+  pref_store = new JsonPrefStore(pref_file, message_loop_.message_loop_proxy());
+  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE, pref_store->ReadPrefs());
+  ASSERT_FALSE(pref_store->ReadOnly());
+
+  // Check values.
+  const Value* result = NULL;
+  EXPECT_TRUE(pref_store->GetValue("list", &result));
+  ListValue().Equals(result);
+  EXPECT_TRUE(pref_store->GetValue("dict", &result));
+  DictionaryValue().Equals(result);
+}
+
 // Tests asynchronous reading of the file when there is no file.
 TEST_F(JsonPrefStoreTest, AsyncNonExistingFile) {
   base::FilePath bogus_input_file = data_dir_.AppendASCII("read.txt");
@@ -237,51 +256,4 @@ TEST_F(JsonPrefStoreTest, AsyncNonExistingFile) {
   EXPECT_FALSE(pref_store->ReadOnly());
 }
 
-TEST_F(JsonPrefStoreTest, NeedsEmptyValue) {
-  base::FilePath pref_file = temp_dir_.path().AppendASCII("write.json");
-
-  ASSERT_TRUE(base::CopyFile(
-      data_dir_.AppendASCII("read.need_empty_value.json"),
-      pref_file));
-
-  // Test that the persistent value can be loaded.
-  ASSERT_TRUE(PathExists(pref_file));
-  scoped_refptr<JsonPrefStore> pref_store =
-      new JsonPrefStore(pref_file, message_loop_.message_loop_proxy().get());
-  ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE, pref_store->ReadPrefs());
-  ASSERT_FALSE(pref_store->ReadOnly());
-
-  // The JSON file looks like this:
-  // {
-  //   "list": [ 1 ],
-  //   "list_needs_empty_value": [ 2 ],
-  //   "dict": {
-  //     "dummy": true,
-  //   },
-  //   "dict_needs_empty_value": {
-  //     "dummy": true,
-  //   },
-  // }
-
-  // Set flag to preserve empty values for the following keys.
-  pref_store->MarkNeedsEmptyValue("list_needs_empty_value");
-  pref_store->MarkNeedsEmptyValue("dict_needs_empty_value");
-
-  // Set all keys to empty values.
-  pref_store->SetValue("list", new base::ListValue);
-  pref_store->SetValue("list_needs_empty_value", new base::ListValue);
-  pref_store->SetValue("dict", new base::DictionaryValue);
-  pref_store->SetValue("dict_needs_empty_value", new base::DictionaryValue);
-
-  // Write to file.
-  pref_store->CommitPendingWrite();
-  RunLoop().RunUntilIdle();
-
-  // Compare to expected output.
-  base::FilePath golden_output_file =
-      data_dir_.AppendASCII("write.golden.need_empty_value.json");
-  ASSERT_TRUE(PathExists(golden_output_file));
-  EXPECT_TRUE(TextContentsEqual(golden_output_file, pref_file));
-}
-
 }  // namespace base