Add a presubmit check for element.$.localId

chrome/browser/web_dev_style/js_checker_test.py

 #!/usr/bin/env python
 # Copyright 2015 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.
 
 import js_checker
 from os import path as os_path
 import re
 from sys import path as sys_path
 import test_util
@@ skipping 222 matching lines @@
   def testInheritDocPasses(self):
     lines = [
         "And then I said, but I won't @inheritDoc! Hahaha!",
         " If your dad's a doctor, do you inheritDoc?",
         "  What's up, inherit doc?",
         "   this.inheritDoc(someDoc)",
     ]
     for line in lines:
       self.ShouldPassInheritDocCheck(line)
 
+  def ShouldFailPolymerLocalIdCheck(self, line):
+    """Checks that element.$.localId check marks |line| as a style error."""
+    error = self.checker.PolymerLocalIdCheck(1, line)
+    self.assertNotEqual('', error,
+        msg='Should be flagged as a style error: ' + line)
+    self.assertTrue('.$' in test_util.GetHighlight(line, error))
+
+  def ShouldPassPolymerLocalIdCheck(self, line):
+    """Checks that element.$.localId check doesn't mark |line| as a style
+       error."""
+    self.assertEqual('', self.checker.PolymerLocalIdCheck(1, line),
+        msg='Should not be flagged as a style error: ' + line)
+
+  def testPolymerLocalIdFails(self):
+    lines = [
+        "cat.$.dog",
+        "thing1.$.thing2",
+        "element.$.localId",
+        "element.$['fancy-hyphenated-id']",
+    ]
+    for line in lines:
+      self.ShouldFailPolymerLocalIdCheck(line)
+
+  def testPolymerLocalIdPasses(self):
+    lines = [
+        "this.$.id",
+        "this.$.localId",
+        "this.$['fancy-id']",
+    ]
+    for line in lines:
+      self.ShouldPassPolymerLocalIdCheck(line)
+
   def ShouldFailWrapperTypeCheck(self, line):
     """Checks that the use of wrapper types (i.e. new Number(), @type {Number})
        is a style error.
     """
     error = self.checker.WrapperTypeCheck(1, line)
     self.assertNotEqual('', error,
         msg='Should be flagged as style error: ' + line)
     highlight = test_util.GetHighlight(line, error)
     self.assertTrue(highlight in ('Boolean', 'Number', 'String'))
 
@@ skipping 67 matching lines @@
         " var SCARE_SMALL_CHILDREN = [",         # TODO(dbeam): add @const in
                                                  # front of all these vars like
         "/** @const */ CONST_VAR = 1;",          # this line has (<--).
     ]
     for line in lines:
       self.ShouldPassVarNameCheck(line)
 
 
 if __name__ == '__main__':
   unittest.main()