4 files changed, 64 insertions, 16 deletions
diff --git a/webkit/fileapi/file_system_url.cc b/webkit/fileapi/file_system_url.cc
index 52dbce6..f3053a4 100644
--- a/webkit/fileapi/file_system_url.cc
+++ b/webkit/fileapi/file_system_url.cc
@@ -114,6 +114,13 @@ FileSystemURL FileSystemURL::WithPath(const FilePath& path) const {
   return url;
 }
 
+bool FileSystemURL::IsParent(const FileSystemURL& child) const {
+  return origin() == child.origin() &&
+         type() == child.type() &&
+         filesystem_id() == child.filesystem_id() &&
+         path().IsParent(child.path());
+}
+
 bool FileSystemURL::operator==(const FileSystemURL& that) const {
   return origin_ == that.origin_ &&
       type_ == that.type_ &&
diff --git a/webkit/fileapi/file_system_url.h b/webkit/fileapi/file_system_url.h
index 12f465a..cabe79d 100644
--- a/webkit/fileapi/file_system_url.h
+++ b/webkit/fileapi/file_system_url.h
@@ -93,6 +93,9 @@ class FILEAPI_EXPORT FileSystemURL {
   // original filesystem: URL in the current implementation).
   FileSystemURL WithPath(const FilePath& path) const;
 
+  // Returns true if this URL is a strict parent of the |child|.
+  bool IsParent(const FileSystemURL& child) const;
+
   bool operator==(const FileSystemURL& that) const;
 
   struct FILEAPI_EXPORT Comparator {
diff --git a/webkit/fileapi/file_system_url_unittest.cc b/webkit/fileapi/file_system_url_unittest.cc
index 3378919..46ae5b3 100644
--- a/webkit/fileapi/file_system_url_unittest.cc
+++ b/webkit/fileapi/file_system_url_unittest.cc
@@ -10,14 +10,18 @@
 #include "webkit/fileapi/file_system_types.h"
 #include "webkit/fileapi/file_system_util.h"
 #include "webkit/fileapi/isolated_context.h"
+#include "webkit/fileapi/syncable/syncable_file_system_util.h"
 
 #define FPL FILE_PATH_LITERAL
 
 namespace fileapi {
+
 namespace {
-FileSystemURL CreateFileSystemURL(const char* url) {
- return FileSystemURL(GURL(url));
+
+FileSystemURL CreateFileSystemURL(const std::string& url_string) {
+ return FileSystemURL(GURL(url_string));
 }
+
 }  // namespace
 
 TEST(FileSystemURLTest, ParsePersistent) {
@@ -157,4 +161,48 @@ TEST(FileSystemURLTest, WithPathForExternal) {
   }
 }
 
+TEST(FileSystemURLTest, IsParent) {
+  ScopedExternalFileSystem scoped1("foo", kFileSystemTypeSyncable, FilePath());
+  ScopedExternalFileSystem scoped2("bar", kFileSystemTypeSyncable, FilePath());
+
+  const std::string root1 = GetFileSystemRootURI(
+      GURL("http://example.com"), kFileSystemTypeTemporary).spec();
+  const std::string root2 = GetSyncableFileSystemRootURI(
+      GURL("http://example.com"), "foo").spec();
+  const std::string root3 = GetSyncableFileSystemRootURI(
+      GURL("http://example.com"), "bar").spec();
+  const std::string root4 = GetFileSystemRootURI(
+      GURL("http://chromium.org"), kFileSystemTypeTemporary).spec();
+
+  const std::string parent("dir");
+  const std::string child("dir/child");
+  const std::string other("other");
+
+  // True cases.
+  EXPECT_TRUE(CreateFileSystemURL(root1 + parent).IsParent(
+      CreateFileSystemURL(root1 + child)));
+  EXPECT_TRUE(CreateFileSystemURL(root2 + parent).IsParent(
+      CreateFileSystemURL(root2 + child)));
+
+  // False cases: the path is not a child.
+  EXPECT_FALSE(CreateFileSystemURL(root1 + parent).IsParent(
+      CreateFileSystemURL(root1 + other)));
+  EXPECT_FALSE(CreateFileSystemURL(root1 + parent).IsParent(
+      CreateFileSystemURL(root1 + parent)));
+  EXPECT_FALSE(CreateFileSystemURL(root1 + child).IsParent(
+      CreateFileSystemURL(root1 + parent)));
+
+  // False case: different types.
+  EXPECT_FALSE(CreateFileSystemURL(root1 + parent).IsParent(
+      CreateFileSystemURL(root2 + child)));
+
+  // False case: different filesystem ID.
+  EXPECT_FALSE(CreateFileSystemURL(root1 + parent).IsParent(
+      CreateFileSystemURL(root3 + child)));
+
+  // False case: different origins.
+  EXPECT_FALSE(CreateFileSystemURL(root1 + parent).IsParent(
+      CreateFileSystemURL(root4 + child)));
+}
+
 }  // namespace fileapi
diff --git a/webkit/fileapi/syncable/local_file_sync_status.cc b/webkit/fileapi/syncable/local_file_sync_status.cc
index 5e153a4..0ef59f6 100644
--- a/webkit/fileapi/syncable/local_file_sync_status.cc
+++ b/webkit/fileapi/syncable/local_file_sync_status.cc
@@ -6,16 +6,6 @@
 
 namespace fileapi {
 
-namespace {
-
-bool IsParent(const FileSystemURL& a, const FileSystemURL& b) {
-  return a.origin() == b.origin() &&
-         a.type() == b.type() &&
-         a.path().IsParent(b.path());
-}
-
-}  // namespace
-
 LocalFileSyncStatus::LocalFileSyncStatus() {}
 
 LocalFileSyncStatus::~LocalFileSyncStatus() {
@@ -71,10 +61,10 @@ bool LocalFileSyncStatus::IsChildOrParentWriting(
   lock_.AssertAcquired();
   URLCountMap::const_iterator upper = writing_.upper_bound(url);
   URLCountMap::const_reverse_iterator rupper(upper);
-  if (upper != writing_.end() && IsParent(url, upper->first))
+  if (upper != writing_.end() && url.IsParent(upper->first))
     return true;
   if (rupper != writing_.rend() &&
-      (rupper->first == url || IsParent(rupper->first, url)))
+      (rupper->first == url || rupper->first.IsParent(url)))
     return true;
   return false;
 }
@@ -84,10 +74,10 @@ bool LocalFileSyncStatus::IsChildOrParentSyncing(
   lock_.AssertAcquired();
   URLSet::const_iterator upper = syncing_.upper_bound(url);
   URLSet::const_reverse_iterator rupper(upper);
-  if (upper != syncing_.end() && IsParent(url, *upper))
+  if (upper != syncing_.end() && url.IsParent(*upper))
     return true;
   if (rupper != syncing_.rend() &&
-      (*rupper == url || IsParent(*rupper, url)))
+      (*rupper == url || rupper->IsParent(url)))
     return true;
   return false;
 }