Add skip_canned option to presubmit_support.

presubmit_support.py

Index: presubmit_support.py
diff --git a/presubmit_support.py b/presubmit_support.py
index 513e22ab821ba342a0a4c2015e7f1a37e762c2fd..70059445856f7029d347281a49c555642c25380a 100755
--- a/presubmit_support.py
+++ b/presubmit_support.py
@@ -1221,6 +1221,10 @@ def Main(argv):
                     "system directories will also be searched.")
   parser.add_option("--default_presubmit")
   parser.add_option("--may_prompt", action='store_true', default=False)
+  parser.add_option("--skip_canned", action='append', default=[],
+                    help="A list of checks to skip which appear in "
+                    "presubmit_canned_checks. Can be provided multiple times "
+                    "to skip multiple canned checks.")
   parser.add_option("--rietveld_url", help=optparse.SUPPRESS_HELP)
   parser.add_option("--rietveld_email", help=optparse.SUPPRESS_HELP)
   parser.add_option("--rietveld_password", help=optparse.SUPPRESS_HELP)
@@ -1241,6 +1245,12 @@ def Main(argv):
         options.rietveld_url,
         options.rietveld_email,
         options.rietveld_password)
+  for method_name in options.skip_canned:

[M-A Ruel, 2013/03/07 15:50:33]

I'd like you to restore them after.

missing = [m for m in options.skip_canned if not
hasattr(presubmit_canned_checks, m)]
if missing:
  parser.error(
      'Attempted to skip nonexistent canned presubmit check: %s' % ',
'.join(missing))

previous = dict((m, getattr(presubmit_canned_checks, m)) for m in
options.skip_canned)

try:
..
except ...:
...
finally:
  for m, l in previous.iteritems():
    setattr(...

+    if hasattr(presubmit_canned_checks, method_name):
+      setattr(presubmit_canned_checks, method_name, lambda *_a, **_kw: [])
+    else:
+      parser.error('Attempted to skip nonexistent canned presubmit check: %s'
+                   % method_name)
   try:
     results = DoPresubmitChecks(
         change_class(options.name,