Make isolate.py fail if Go isolate fails

scripts/slave/recipe_modules/isolate/resources/isolate.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.
 
-"""Calls either isolate.py or isolate Go executable in the checkout.
+"""Calls the isolate Go executable in the checkout, failing if it cannot run.
 """
 
+# TODO(djd): make the caller invoke the Go binary directly, kill this script.
+
 import os
 import subprocess
 import sys
 
 
 def try_go(path, args):
   """Tries to run the Go implementation of isolate.
-
-  Returns None if it should fall back to the python implementation.
   """
   luci_go = os.path.join(os.path.dirname(path), 'luci-go')
   if sys.platform == 'win32':
     exe = os.path.join(luci_go, 'win64', 'isolate.exe')
   elif sys.platform == 'darwin':
     exe = os.path.join(luci_go, 'mac64', 'isolate')
   else:
     exe = os.path.join(luci_go, 'linux64', 'isolate')
-  if not os.access(exe, os.X_OK):
-    return None
-
-  # Try to use Go implementation.
-  try:
-    version = subprocess.check_output([exe, 'version']).strip()
-    version = tuple(map(int, version.split('.')))
-  except (subprocess.CalledProcessError, OSError, ValueError):
-    return None
-
-  expected = (0, 2, 2)
-
-  # Enlarge both tuples so (1, 0) == (1, 0, 0).
-  while len(version) < len(expected):
-    version = tuple(list(version) + [0])
-  while len(expected) < len(version):
-    version = tuple(list(expected) + [0])
-
-  # Key behavior based on version if necessary.
-  if version < expected:
-    print('Expected %s, found %s' % '.'.join(expected), '.'.join(version))
-    return None
 
   return subprocess.call([exe] + args)

[mithro, 2016/11/02 07:13:11]

Maybe you want to use subprocess.check_call ?

 
 
 def main():
   path = sys.argv[1]
   args = sys.argv[2:]
-  ret = try_go(path, args)
-  if ret is None:
-    return subprocess.call(
-        [sys.executable, os.path.join(path, 'isolate.py')] + args)
-  return ret
+  return try_go(path, args)
 
 
 if __name__ == '__main__':
   sys.exit(main())