Add CheckVPythonSpec for verifying .vpython file syntax

This check will be used in Chromium, V8 and Catapult PRESUBMIT scripts.

R=maruel@chromium.org, tandrii@chromium.org

Bug: 777893
Change-Id: I2ca1e774b89787c4d3b5f336315d145571858864
Reviewed-on: https://chromium-review.googlesource.com/738169
Commit-Queue: Sergiy Byelozyorov <sergiyb@google.com>
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>
Reviewed-by: Daniel Jacques <dnj@chromium.org>

presubmit_canned_checks.py

@@ -1279,3 +1279,32 @@ def CheckCIPDPackages(input_api, output_api, platforms, packages):
   for k, v in packages.iteritems():
     manifest.append('%s %s' % (k, v))
   return CheckCIPDManifest(input_api, output_api, content='\n'.join(manifest))
+
+
+def CheckVPythonSpec(input_api, output_api, file_filter=None):
+  """Validates any changed .vpython files with vpython verification tool.
+
+  Args:
+    input_api: Bag of input related interfaces.
+    output_api: Bag of output related interfaces.
+    file_filter: Custom function that takes a path (relative to client root) and
+      returns boolean, which is used to filter files for which to apply the
+      verification to. Defaults to any path ending with .vpython, which captures
+      both global .vpython and <script>.vpython files.
+
+  Returns:
+    A list of input_api.Command objects containing verification commands.
+  """
+  file_filter = file_filter or (lambda f: f.LocalPath().endswith('.vpython'))
+  affected_files = input_api.AffectedFiles(file_filter=file_filter)
+  affected_files = map(lambda f: f.AbsoluteLocalPath(), affected_files)
+
+  commands = []
+  for f in affected_files:
+    commands.append(input_api.Command(
+      'Verify %s' % f,
+      ['vpython', '-vpython-spec', f, '-vpython-tool', 'verify'],
+      {'stderr': input_api.subprocess.STDOUT},
+      output_api.PresubmitError))
+
+  return commands

tests/presubmit_unittest.py

@@ -1707,6 +1707,7 @@ class CannedChecksUnittest(PresubmitTestsBase):
       'CheckGNFormatted',
       'CheckRietveldTryJobExecution',
       'CheckSingletonInHeaders',
+      'CheckVPythonSpec',
       'RunPythonUnitTests', 'RunPylint',
       'RunUnitTests', 'RunUnitTestsInDirectory',
       'GetCodereviewOwnerAndReviewers',
@@ -2832,6 +2833,31 @@ class CannedChecksUnittest(PresubmitTestsBase):
         ['cipd', 'ensure-file-verify', '-ensure-file=-'])
     self.assertEquals(command.kwargs, {'stdin': content})
 
+  def testCannedCheckVPythonSpec(self):
+    change = presubmit.Change('a', 'b', self.fake_root_dir, None, 0, 0, None)
+    input_api = self.MockInputApi(change, False)
+
+    affected_file = self.mox.CreateMock(presubmit.GitAffectedFile)
+    affected_file.AbsoluteLocalPath().AndReturn('/path1/to/.vpython')
+    input_api.AffectedFiles(
+        file_filter=mox.IgnoreArg()).AndReturn([affected_file])
+
+    self.mox.ReplayAll()
+
+    commands = presubmit_canned_checks.CheckVPythonSpec(
+        input_api, presubmit.OutputApi)
+    self.assertEqual(len(commands), 1)
+    self.assertEqual(commands[0].name, 'Verify /path1/to/.vpython')
+    self.assertEqual(commands[0].cmd, [
+      'vpython',
+      '-vpython-spec', '/path1/to/.vpython',
+      '-vpython-tool', 'verify'
+    ])
+    self.assertDictEqual(
+        commands[0].kwargs, {'stderr': input_api.subprocess.STDOUT})
+    self.assertEqual(commands[0].message, presubmit.OutputApi.PresubmitError)
+    self.assertIsNone(commands[0].info)
+
 
 if __name__ == '__main__':
   import unittest