Remove BOM from js and css files in content script.

BUG=38152
TEST=Inject css file with BOM using an extension. It should be injected without BOM.

Review URL: http://codereview.chromium.org/2453005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@48885 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 51 insertions, 21 deletions

diff --git a/chrome/browser/extensions/user_script_master.cc b/chrome/browser/extensions/user_script_master.cc
index bedc7a8..960bc49 100644
--- a/chrome/browser/extensions/user_script_master.cc
+++ b/chrome/browser/extensions/user_script_master.cc
@@ -53,11 +53,6 @@ bool UserScriptMaster::ScriptReloader::ParseMetadataHeader(
   // http://wiki.greasespot.net/Metadata_block
   base::StringPiece line;
   size_t line_start = 0;
-
-  // Skip UTF-8's BOM.
-  if (script_text.starts_with(kUtf8ByteOrderMark))
-    line_start += strlen(kUtf8ByteOrderMark);
-
   size_t line_end = line_start;
   bool in_metadata = false;
 
@@ -165,11 +160,19 @@ static bool LoadScriptContent(UserScript::File* script_file) {
     return false;
   }
 
-  script_file->set_content(content);
+  // Remove BOM from the content.
+  std::string::size_type index = content.find(kUtf8ByteOrderMark);
+  if (index == 0) {
+    script_file->set_content(content.substr(strlen(kUtf8ByteOrderMark)));
+  } else {
+    script_file->set_content(content);
+  }
+
   LOG(INFO) << "Loaded user script file: " << path.value();
   return true;
 }
 
+// static
 void UserScriptMaster::ScriptReloader::LoadScriptsFromDirectory(
     const FilePath& script_dir, UserScriptList* result) {
   // Clear the list. We will populate it with the scripts found in script_dir.
diff --git a/chrome/browser/extensions/user_script_master_unittest.cc b/chrome/browser/extensions/user_script_master_unittest.cc
index ec8c728..3760941 100644
--- a/chrome/browser/extensions/user_script_master_unittest.cc
+++ b/chrome/browser/extensions/user_script_master_unittest.cc
@@ -203,21 +203,6 @@ TEST_F(UserScriptMasterTest, Parse6) {
 }
 
 TEST_F(UserScriptMasterTest, Parse7) {
-  const std::string text(
-    "\xEF\xBB\xBF// ==UserScript==\n"
-    "// @match http://*.mail.google.com/*\n"
-    "// ==/UserScript==\n");
-
-  // Should Ignore UTF-8's BOM.
-  UserScript script;
-  EXPECT_TRUE(UserScriptMaster::ScriptReloader::ParseMetadataHeader(
-      text, &script));
-  ASSERT_EQ(1U, script.url_patterns().size());
-  EXPECT_EQ("http://*.mail.google.com/*",
-            script.url_patterns()[0].GetAsString());
-}
-
-TEST_F(UserScriptMasterTest, Parse8) {
   // Greasemonkey allows there to be any leading text before the comment marker.
   const std::string text(
     "// ==UserScript==\n"
@@ -235,3 +220,45 @@ TEST_F(UserScriptMasterTest, Parse8) {
   EXPECT_EQ("http://mail.yahoo.com/*",
             script.url_patterns()[0].GetAsString());
 }
+
+TEST_F(UserScriptMasterTest, SkipBOMAtTheBeginning) {
+  FilePath path = script_dir_.AppendASCII("script.user.js");
+
+  const std::string content(
+    "\xEF\xBB\xBF// ==UserScript==\n"
+    "// @match http://*.mail.google.com/*\n"
+    "// ==/UserScript==\n");
+  size_t written = file_util::WriteFile(path, content.c_str(), content.size());
+  ASSERT_EQ(written, content.size());
+
+  UserScriptList script_list;
+  UserScriptMaster::ScriptReloader::LoadScriptsFromDirectory(
+      script_dir_, &script_list);
+  ASSERT_EQ(1U, script_list.size());
+
+  EXPECT_EQ(content.substr(3),
+            script_list[0].js_scripts()[0].GetContent().as_string());
+  EXPECT_EQ("http://*.mail.google.com/*",
+            script_list[0].url_patterns()[0].GetAsString());
+}
+
+TEST_F(UserScriptMasterTest, LeaveBOMNotAtTheBeginning) {
+  FilePath path = script_dir_.AppendASCII("script.user.js");
+
+  const std::string content(
+    "// ==UserScript==\n"
+    "// @match http://*.mail.google.com/*\n"
+    "// ==/UserScript==\n"
+    "// @bom \xEF\xBB\xBF");
+  size_t written = file_util::WriteFile(path, content.c_str(), content.size());
+  ASSERT_EQ(written, content.size());
+
+  UserScriptList script_list;
+  UserScriptMaster::ScriptReloader::LoadScriptsFromDirectory(
+      script_dir_, &script_list);
+  ASSERT_EQ(1U, script_list.size());
+
+  EXPECT_EQ(content, script_list[0].js_scripts()[0].GetContent().as_string());
+  EXPECT_EQ("http://*.mail.google.com/*",
+            script_list[0].url_patterns()[0].GetAsString());
+}