Improve performance of extension docs generation by 60%.

Review URL: http://codereview.chromium.org/9996002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@132692 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 40 insertions, 0 deletions

diff --git a/tools/json_comment_eater.py b/tools/json_comment_eater.py
new file mode 100755
index 0000000..1b1e07a84
--- /dev/null
+++ b/tools/json_comment_eater.py
@@ -0,0 +1,40 @@
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+""" Utility to remove comments from JSON files so that they can be parsed by
+json.loads."""
+
+def _ReadString(input, start, output):
+  output.append('"')
+  in_escape = False
+  for pos in xrange(start, len(input)):
+    output.append(input[pos])
+    if in_escape:
+      in_escape = False
+    else:
+      if input[pos] == '\\':
+        in_escape = True
+      elif input[pos] == '"':
+        return pos + 1
+  return pos
+
+def _ReadComment(input, start, output):
+  for pos in xrange(start, len(input)):
+    if input[pos] in ['\r', '\n']:
+      output.append(input[pos])
+      return pos + 1
+  return pos
+
+def Nom(input):
+  output = []
+  pos = 0
+  while pos < len(input):
+    if input[pos] == '"':
+      pos = _ReadString(input, pos + 1, output)
+    elif input[pos:pos+2] == '//':
+      pos = _ReadComment(input, pos + 2, output)
+    else:
+      output.append(input[pos])
+      pos += 1
+  return ''.join(output)