Mojo/web_dev_style: add a presubmit discouraging mojo_bindings.js

mojo_bindings_lite.js should be used in new (and eventually current)
code.

R=dpapad@chromium.org
BUG=931798

Change-Id: I6499a02c848412d7a2ba4c3d84fcc202e2813bf3
Reviewed-on: https://chromium-review.googlesource.com/c/1474517
Commit-Queue: Dan Beam <dbeam@chromium.org>
Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Auto-Submit: Dan Beam <dbeam@chromium.org>
Cr-Commit-Position: refs/heads/master@{#634547}

tools/web_dev_style/resource_checker.py

@@ -15,9 +15,13 @@ class ResourceChecker(object):
     self.output_api = output_api
     self.file_filter = file_filter
 
+  def DeprecatedMojoBindingsCheck(self, line_number, line):
+    return regex_check.RegexCheck(self.input_api.re, line_number, line,
+        '(mojo_bindings\.js)', 'Please use mojo_bindings_lite.js in new code')
+
   def DisallowIncludeCheck(self, msg, line_number, line):
     return regex_check.RegexCheck(self.input_api.re, line_number, line,
-              '^\s*(?:\/[\*\/])?\s*(<include)\s*src=', msg)
+        '^\s*(?:\/[\*\/])?\s*(<include)\s*src=', msg)
 
   # This is intentionally not included in RunChecks(). It's an optional check
   # that can be used from a PRESUBMIT.py in a directory that does not wish to
@@ -30,13 +34,17 @@ class ResourceChecker(object):
 
   def SelfClosingIncludeCheck(self, line_number, line):
     return regex_check.RegexCheck(self.input_api.re, line_number, line,
-        "(</include>|<include.*/>)", "Closing <include> tags is unnecessary.")
+        '(</include>|<include.*/>)', 'Closing <include> tags is unnecessary.')
 
   def RunChecks(self):
-    return self._RunCheckOnAffectedFiles(
-        self.SelfClosingIncludeCheck, 'Found resources style issues in %s')
+    msg = 'Found resources style issues in %s'
+    # TODO(crbug.com/931798): is_error for Mojo check when -lite is majority?
+    return self._RunCheckOnAffectedFiles(self.DeprecatedMojoBindingsCheck,
+        msg, only_changed_lines=True) + \
+        self._RunCheckOnAffectedFiles(self.SelfClosingIncludeCheck, msg)
 
-  def _RunCheckOnAffectedFiles(self, check, msg_template, is_error=False):
+  def _RunCheckOnAffectedFiles(self, check, msg_template, is_error=False,
+                               only_changed_lines=False):
     """Check for violations of the Chromium web development style guide. See
        https://chromium.googlesource.com/chromium/src/+/master/styleguide/web/web.md
     """
@@ -46,8 +54,11 @@ class ResourceChecker(object):
                                                  include_deletes=False)
     for f in affected_files:
       errors = []
-
-      for line_number, line in enumerate(f.NewContents(), start=1):
+      if only_changed_lines:
+        contents = f.ChangedContents()
+      else:
+        contents = enumerate(f.NewContents(), start=1)
+      for line_number, line in contents:
         error = check(line_number, line)
         if error:
           errors.append(error)

tools/web_dev_style/resource_checker_test.py

@@ -26,40 +26,30 @@ class ResourceCheckerTest(SuperMoxTestBase):
     output_api = self.mox.CreateMockAnything()
     self.checker = resource_checker.ResourceChecker(input_api, output_api)
 
-  def ShouldFailSelfClosingIncludeCheck(self, line):
-    """Checks that the '</include>' checker flags |line| as a style error."""
-    error = self.checker.SelfClosingIncludeCheck(1, line)
-    self.assertNotEqual('', error,
-        'Should be flagged as style error: ' + line)
-    highlight = test_util.GetHighlight(line, error).strip()
-    self.assertTrue('include' in highlight and highlight[0] == '<')
+  def ShouldPassDeprecatedMojoBindingCheck(self, line):
+    error = self.checker.DeprecatedMojoBindingsCheck(1, line)
+    self.assertEqual('', error, 'Should not be flagged as error: ' + line)
 
-  def ShouldPassSelfClosingIncludeCheck(self, line):
-    """Checks that the '</include>' checker doesn't flag |line| as an error."""
-    self.assertEqual('', self.checker.SelfClosingIncludeCheck(1, line),
-        'Should not be flagged as style error: ' + line)
+  def ShouldFailDeprecatedMojoBindingCheck(self, line):
+    error = self.checker.DeprecatedMojoBindingsCheck(1, line)
+    self.assertNotEqual('', error, 'Should be flagged as error: ' + line)
+    self.assertEquals('mojo_bindings.js', test_util.GetHighlight(line, error))
 
-  def testIncludeFails(self):
+  def testDeprecatedMojoBindingsCheckPasses(self):
     lines = [
-        "</include>   ",
-        "    </include>",
-        "    </include>   ",
-        '  <include src="blah.js" />   ',
-        '<include src="blee.js"/>',
+      '<script src="chrome://resources/js/mojo_bindings_lite.js">',
+      "script.src = 'chrome://resources/js/mojo_bindings_lite.js';",
     ]
     for line in lines:
-      self.ShouldFailSelfClosingIncludeCheck(line)
+      self.ShouldPassDeprecatedMojoBindingCheck(line)
 
-  def testIncludePasses(self):
+  def testDeprecatedMojoBindingsCheckFails(self):
     lines = [
-        '<include src="assert.js">',
-        "<include src='../../assert.js'>",
-        "<i>include src='blah'</i>",
-        "</i>nclude",
-        "</i>include",
+      '<script src="chrome://resources/js/mojo_bindings.js">',
+      "script.src = 'chrome://resources/js/mojo_bindings.js';",
     ]
     for line in lines:
-      self.ShouldPassSelfClosingIncludeCheck(line)
+      self.ShouldFailDeprecatedMojoBindingCheck(line)
 
   def ShouldPassDisallowIncludeCheck(self, line):
     self.assertEqual('', self.checker.DisallowIncludeCheck('msg', 1, line),
@@ -87,6 +77,41 @@ class ResourceCheckerTest(SuperMoxTestBase):
     for line in lines:
       self.ShouldPassDisallowIncludeCheck(line)
 
+  def ShouldFailSelfClosingIncludeCheck(self, line):
+    """Checks that the '</include>' checker flags |line| as a style error."""
+    error = self.checker.SelfClosingIncludeCheck(1, line)
+    self.assertNotEqual('', error,
+        'Should be flagged as style error: ' + line)
+    highlight = test_util.GetHighlight(line, error).strip()
+    self.assertTrue('include' in highlight and highlight[0] == '<')
+
+  def ShouldPassSelfClosingIncludeCheck(self, line):
+    """Checks that the '</include>' checker doesn't flag |line| as an error."""
+    self.assertEqual('', self.checker.SelfClosingIncludeCheck(1, line),
+        'Should not be flagged as style error: ' + line)
+
+  def testIncludeFails(self):
+    lines = [
+        "</include>   ",
+        "    </include>",
+        "    </include>   ",
+        '  <include src="blah.js" />   ',
+        '<include src="blee.js"/>',
+    ]
+    for line in lines:
+      self.ShouldFailSelfClosingIncludeCheck(line)
+
+  def testIncludePasses(self):
+    lines = [
+        '<include src="assert.js">',
+        "<include src='../../assert.js'>",
+        "<i>include src='blah'</i>",
+        "</i>nclude",
+        "</i>include",
+    ]
+    for line in lines:
+      self.ShouldPassSelfClosingIncludeCheck(line)
+
 
 if __name__ == '__main__':
   unittest.main()