Remove emtpy lists and empty dictionaries from Preferences and

Local State when writing to disk.

BUG=28836

Review URL: http://codereview.chromium.org/449074

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@33518 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 75 insertions, 0 deletions

diff --git a/base/values_unittest.cc b/base/values_unittest.cc
index 5835e2b..912b380 100644
--- a/base/values_unittest.cc
+++ b/base/values_unittest.cc
@@ -478,3 +478,78 @@ TEST(ValuesTest, Equals) {
   EXPECT_FALSE(dv.Equals(copy));
   delete copy;
 }
+
+TEST(ValuesTest, RemoveEmptyChildren) {
+  scoped_ptr<DictionaryValue> root(new DictionaryValue);
+  // Remove empty lists and dictionaries.
+  root->Set(L"empty_dict", new DictionaryValue);
+  root->Set(L"empty_list", new ListValue);
+  root->SetWithoutPathExpansion(L"a.b.c.d.e", new DictionaryValue);
+  root.reset(root->DeepCopyWithoutEmptyChildren());
+  EXPECT_TRUE(root->empty());
+
+  // Make sure we don't prune too much.
+  root->SetBoolean(L"bool", true);
+  root->Set(L"empty_dict", new DictionaryValue);
+  root->SetString(L"empty_string", "");
+  root.reset(root->DeepCopyWithoutEmptyChildren());
+  EXPECT_EQ(2U, root->size());
+
+  // Should do nothing.
+  root.reset(root->DeepCopyWithoutEmptyChildren());
+  EXPECT_EQ(2U, root->size());
+
+  // Nested test cases.  These should all reduce back to the bool and string
+  // set above.
+  {
+    root->Set(L"a.b.c.d.e", new DictionaryValue);
+    root.reset(root->DeepCopyWithoutEmptyChildren());
+    EXPECT_EQ(2U, root->size());
+  }
+  {
+    DictionaryValue* inner = new DictionaryValue;
+    root->Set(L"dict_with_emtpy_children", inner);
+    inner->Set(L"empty_dict", new DictionaryValue);
+    inner->Set(L"empty_list", new ListValue);
+    root.reset(root->DeepCopyWithoutEmptyChildren());
+    EXPECT_EQ(2U, root->size());
+  }
+  {
+    ListValue* inner = new ListValue;
+    root->Set(L"list_with_empty_children", inner);
+    inner->Append(new DictionaryValue);
+    inner->Append(new ListValue);
+    root.reset(root->DeepCopyWithoutEmptyChildren());
+    EXPECT_EQ(2U, root->size());
+  }
+
+  // Nested with siblings.
+  {
+    ListValue* inner = new ListValue;
+    root->Set(L"list_with_empty_children", inner);
+    inner->Append(new DictionaryValue);
+    inner->Append(new ListValue);
+    DictionaryValue* inner2 = new DictionaryValue;
+    root->Set(L"dict_with_empty_children", inner2);
+    inner2->Set(L"empty_dict", new DictionaryValue);
+    inner2->Set(L"empty_list", new ListValue);
+    root.reset(root->DeepCopyWithoutEmptyChildren());
+    EXPECT_EQ(2U, root->size());
+  }
+
+  // Make sure nested values don't get pruned.
+  {
+    ListValue* inner = new ListValue;
+    root->Set(L"list_with_empty_children", inner);
+    ListValue* inner2 = new ListValue;
+    inner->Append(new DictionaryValue);
+    inner->Append(inner2);
+    inner2->Append(Value::CreateStringValue("hello"));
+    root.reset(root->DeepCopyWithoutEmptyChildren());
+    EXPECT_EQ(3U, root->size());
+    EXPECT_TRUE(root->GetList(L"list_with_empty_children", &inner));
+    EXPECT_EQ(1U, inner->GetSize());  // Dictionary was pruned.
+    EXPECT_TRUE(inner->GetList(0, &inner2));
+    EXPECT_EQ(1U, inner2->GetSize());
+  }
+}