WebRTC: Cleanup symlinks before bot_update

scripts/slave/recipe_modules/webrtc/resources/cleanup_symlinks.py

Index: scripts/slave/recipe_modules/webrtc/resources/cleanup_symlinks.py
diff --git a/scripts/slave/recipe_modules/webrtc/resources/cleanup_symlinks.py b/scripts/slave/recipe_modules/webrtc/resources/cleanup_symlinks.py
new file mode 100755
index 0000000000000000000000000000000000000000..95c0bf010a72a7f3eca844bb4de41b6715c4a564
--- /dev/null
+++ b/scripts/slave/recipe_modules/webrtc/resources/cleanup_symlinks.py
@@ -0,0 +1,36 @@
+#!/usr/bin/env python
+# Copyright 2016 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.
+
+"""Script that deletes all symlinks created by setup_links.py in a checkout."""
+
+import os
+import subprocess
+import sys
+
+
+def main(args):
+  if not args or len(args) != 1:

[Michael Achenbach, 2016/11/08 09:11:47]

nit:
if len(args) != 1:
should be enough, since the way you pass it below makes sure it's a list.

[kjellander_chromium, 2016/11/08 11:04:40]

Done.

+    print >> sys.stderr, 'Please specify a single directory as an argument.'
+    return 1
+
+  checkout_dir = args[0]
+  if not os.path.isdir(checkout_dir):
+    print 'Cannot find any directory at %s. Skipping cleaning.' % checkout_dir
+    return 0
+
+  setup_links_file = os.path.join(checkout_dir, 'setup_links.py')
+  if not os.path.isfile(setup_links_file):

[Michael Achenbach, 2016/11/08 09:11:47]

Does "isfile" imply "exists"? Or can it raise?

[ehmaldonado_chromium, 2016/11/08 10:43:25]

It doesn't raise.

[kjellander_chromium, 2016/11/08 11:04:40]

Acknowledged.

+    print 'Cannot find %s. Incomplete checkout?' % setup_links_file
+    return 1
+  else:
+    print 'Cleaning up symlinks in %s' % checkout_dir
+    subprocess.check_call([sys.executable, setup_links_file, '--clean-only'],
+                          cwd=checkout_dir)
+    return 0
+
+
+
+if __name__ == '__main__':
+  sys.exit(main(sys.argv[1:]))