PRESUBMIT check for JavaScript style errors

chrome/browser/resources/web_dev_style/js_checker.py

Index: chrome/browser/resources/web_dev_style/js_checker.py
diff --git a/chrome/browser/resources/web_dev_style/js_checker.py b/chrome/browser/resources/web_dev_style/js_checker.py
new file mode 100644
index 0000000000000000000000000000000000000000..a6e8103c3de8f2ec2fc86b2804221fdc1ce28cf2
--- /dev/null
+++ b/chrome/browser/resources/web_dev_style/js_checker.py
@@ -0,0 +1,123 @@
+# 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.
+
+"""Presubmit script for Chromium JS resources.
+
+See chrome/browser/resources/PRESUBMIT.py
+"""
+
+class JSChecker(object):
+  def __init__(self, input_api, output_api, file_filter=None):
+    self.input_api = input_api
+    self.output_api = output_api
+    self.file_filter = file_filter
+
+  def RunChecks(self):
+    """Check for violations of the Chromium JavaScript style guide. See
+       http://chromium.org/developers/web-development-style-guide#TOC-JavaScript
+    """
+
+    import sys
+    old_path = sys.path
+
+    try:
+      closure_linter_path = self.input_api.os_path.join(
+          self.input_api.change.RepositoryRoot(),
+          "third_party",
+          "closure_linter")
+      gflags_path = self.input_api.os_path.join(
+          self.input_api.change.RepositoryRoot(),
+          "third_party",
+          "python_gflags")
+
+      sys.path.insert(0, closure_linter_path)
+      sys.path.insert(0, gflags_path)
+
+      from closure_linter import checker, errors
+      from closure_linter.common import errorhandler
+
+    finally:
+      sys.path = old_path
+
+    class ErrorHandlerImpl(errorhandler.ErrorHandler):
+      """Filters out errors that don't apply to Chromium JavaScript code."""
+
+      def __init__(self):
+        self._errors = []
+
+      def HandleFile(self, filename, first_token):
+        self._filename = filename
+
+      def HandleError(self, error):
+        if (self._valid(error)):
+          error.filename = self._filename
+          self._errors.append(error)
+
+      def GetErrors(self):
+        return self._errors
+
+      def HasErrors(self):
+        return bool(self._errors)
+
+      def _valid(self, error):
+        """Check whether an error is valid. Most errors are valid, with a few
+           exceptions which are listed here.
+        """
+
+        return error.code not in [
+            errors.COMMA_AT_END_OF_LITERAL,
+            errors.JSDOC_ILLEGAL_QUESTION_WITH_PIPE,
+            errors.JSDOC_TAG_DESCRIPTION_ENDS_WITH_INVALID_CHARACTER,
+        ]
+
+    results = []
+
+    affected_files = self.input_api.change.AffectedFiles(
+        file_filter=self.file_filter)
+    affected_js_files = filter(lambda f: f.LocalPath().endswith('.js'),
+                               affected_files)
+    for f in affected_js_files:
+      # Skip options_bundle.js since it's just a bunch of <include>s
+      if self.input_api.os_path.split(f.LocalPath())[1] == 'options_bundle.js':
+        continue
+
+      error_lines = []
+
+      # check for getElementById()
+      for i, line in enumerate(f.NewContents(), start=1):
+        if 'getElementById' in line:
+          error_lines.append('  line %d: %s\n%s' % (
+              i,
+              "Use $('id') instead of document.getElementById('id')",
+              line))
+
+      # Use closure_linter to check for several different errors
+      error_handler = ErrorHandlerImpl()
+      js_checker = checker.JavaScriptStyleChecker(error_handler)
+      js_checker.Check(self.input_api.os_path.join(
+          self.input_api.change.RepositoryRoot(),
+          f.LocalPath()))
+
+      for error in error_handler.GetErrors():
+        error_msg = '  line %d: E%04d: %s\n%s' % (
+            error.token.line_number,
+            error.code,
+            error.message,
+            error.token.line)
+        error_lines.append(error_msg)
+
+      if error_lines:
+        error_lines = [
+            'Found JavaScript style violations in %s:' %
+            f.LocalPath()] + error_lines
+        results.append(self.output_api.PresubmitError('\n'.join(error_lines)))
+
+    if results:
+      results.append(self.output_api.PresubmitNotifyResult(
+          'See the JavaScript style guide at '
+          'http://www.chromium.org/developers/web-development-style-guide'
+          '#TOC-JavaScript and if you have any feedback about the JavaScript '
+          'PRESUBMIT check, contact tbreisacher@chromium.org'))
+
+    return results