[Sync] Convert ModelTypeBitSetFromString to not use streams.

BUG=74051
TEST=sync_unit_test

Review URL: http://codereview.chromium.org/6578039

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@76272 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 27 insertions, 9 deletions

diff --git a/chrome/browser/sync/syncable/model_type.cc b/chrome/browser/sync/syncable/model_type.cc
index 35a4c06..e8995e8 100644
--- a/chrome/browser/sync/syncable/model_type.cc
+++ b/chrome/browser/sync/syncable/model_type.cc
@@ -4,8 +4,6 @@
 
 #include "chrome/browser/sync/syncable/model_type.h"
 
-#include <sstream>
-
 #include "base/metrics/histogram.h"
 #include "base/values.h"
 #include "chrome/browser/sync/engine/syncproto.h"
@@ -260,14 +258,13 @@ ModelType ModelTypeFromString(const std::string& model_type_string) {
 bool ModelTypeBitSetFromString(
     const std::string& model_type_bitset_string,
     ModelTypeBitSet* model_types) {
-  if (model_type_bitset_string.length() != MODEL_TYPE_COUNT) {
+  DCHECK(model_types);
+  if (model_type_bitset_string.length() != MODEL_TYPE_COUNT)
     return false;
-  }
-
-  std::istringstream iss(model_type_bitset_string);
-  iss >> *model_types;
-  iss.peek();   // Need to peek before checking EOF.
-  return iss.eof();
+  if (model_type_bitset_string.find_first_not_of("01") != std::string::npos)
+    return false;
+  *model_types = ModelTypeBitSet(model_type_bitset_string);
+  return true;
 }
 
 ListValue* ModelTypeBitSetToValue(const ModelTypeBitSet& model_types) {
diff --git a/chrome/browser/sync/syncable/model_type_unittest.cc b/chrome/browser/sync/syncable/model_type_unittest.cc
index 59ed1f9..df8ca8d 100644
--- a/chrome/browser/sync/syncable/model_type_unittest.cc
+++ b/chrome/browser/sync/syncable/model_type_unittest.cc
@@ -43,5 +43,26 @@ TEST_F(ModelTypeTest, ModelTypeSetToValue) {
   EXPECT_EQ("Apps", types[1]);
 }
 
+TEST_F(ModelTypeTest, ModelTypeBitSetFromString) {
+  ModelTypeBitSet input, output;
+  input.set(BOOKMARKS);
+  input.set(AUTOFILL);
+  input.set(APPS);
+  std::string input_string = input.to_string();
+  EXPECT_TRUE(ModelTypeBitSetFromString(input_string, &output));
+  EXPECT_EQ(input, output);
+
+  input_string.clear();
+  EXPECT_FALSE(ModelTypeBitSetFromString(input_string, &output));
+
+  input_string = "hello world";
+  EXPECT_FALSE(ModelTypeBitSetFromString(input_string, &output));
+
+  input_string.clear();
+  for (int i = 0; i < MODEL_TYPE_COUNT; ++i)
+    input_string += '0' + (i%10);
+  EXPECT_FALSE(ModelTypeBitSetFromString(input_string, &output));
+}
+
 }  // namespace
 }  // namespace syncable