Add a presubmit check to check that a certain set of Android specific files only have deletions.

PRESUBMIT.py

Index: PRESUBMIT.py
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index b3f798920d2b1adf0347fbc559dcb3018ef9423e..ad9effe82d67b7770a7cfdd110472ce8aa095a64 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -193,6 +193,11 @@ _BANNED_CPP_FUNCTIONS = (
 )
 
 
+_DELETIONS_ONLY_FILES = (
+    'build/android/findbugs_filter/findbugs_known_bugs.txt'

[Isaac (away), 2013/01/09 05:40:10]

if you keep this, you need a trailing comma on 197 or _DELETIONS_ONLY_FILES will
be a string, not a tuple.

[Siva Chandra, 2013/01/11 01:24:04]

Done.

+)
+
+
 
 def _CheckNoProductionCodeUsingTestOnlyFunctions(input_api, output_api):
   """Attempts to prevent use of functions intended only for testing in
@@ -628,6 +633,21 @@ def _CheckIncludeOrder(input_api, output_api):
   return results
 
 
+def _CheckDeletionsOnlyFiles(input_api, output_api):
+  """Check that a certain listed files only have deletions.

[Isaac (away), 2013/01/12 02:42:30]

nit: end triple quote on line 637 (delete line 638).

+  """
+  errors = []
+  for f in input_api.AffectedFiles():
+    if f.LocalPath() in _DELETIONS_ONLY_FILES:

[Isaac (away), 2013/01/09 05:40:10]

how about just:

if f.LocalPath() = 'build/android/...'

I don't think we're going to need this function for other files.

[Siva Chandra, 2013/01/11 01:24:04]

Unless you feel generality is bad here, I would prefer to keep it general. In an
other comment, you suggested that I move these changes to build/android. I have
same concern about generality for that as well.

[Isaac (away), 2013/01/12 02:42:30]

SGTM.  It's fine to keep the DELETION_ONLY_FILES as a list, but the style in
this file is to define the list in the narrowest possible scope.  i.e. if the
list is only used in this function, define the list inside the function.

+      if f.ChangedContents():
+        errors.append(f.LocalPath())
+  results = []
+  if errors:
+    results.append(output_api.PresubmitError(
+        'Following files should only contain deletions.', errors))
+  return results
+
+
 def _CommonChecks(input_api, output_api):
   """Checks common to both upload and commit."""
   results = []
@@ -647,6 +667,7 @@ def _CommonChecks(input_api, output_api):
   results.extend(_CheckFilePermissions(input_api, output_api))
   results.extend(_CheckNoAuraWindowPropertyHInHeaders(input_api, output_api))
   results.extend(_CheckIncludeOrder(input_api, output_api))
+  results.extend(_CheckDeletionsOnlyFiles(input_api, output_api))
   return results