PPAPI: Make API changes w/o IDL changes Warnings if generators have changed

ppapi/PRESUBMIT.py

 # Copyright (c) 2012 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.
 
 import os
 import re
 import sys
 import subprocess
 
 
@@ skipping 141 matching lines @@
   results.extend(CheckTODO(input_api, output_api))
 
   results.extend(CheckUnversionedPPB(input_api, output_api))
 
   results.extend(CheckUpdatedNaClSDK(input_api, output_api))
 
   # Verify all modified *.idl have a matching *.h
   files = input_api.LocalPaths()
   h_files = []
   idl_files = []
+  generators_changed = False
 
   # Find all relevant .h and .idl files.
   for filename in files:
     name, ext = os.path.splitext(filename)
     name_parts = name.split(os.sep)
     if name_parts[0:2] == ['ppapi', 'c'] and ext == '.h':
       h_files.append('/'.join(name_parts[2:]))
-    if name_parts[0:2] == ['ppapi', 'api'] and ext == '.idl':
+    elif name_parts[0:2] == ['ppapi', 'api'] and ext == '.idl':
       idl_files.append('/'.join(name_parts[2:]))
+    elif name_parts[0:2] == ['ppapi', 'generators']:
+      generators_changed = True
 
   # Generate a list of all appropriate *.h and *.idl changes in this CL.
   both = h_files + idl_files
 
   # If there aren't any, we are done checking.
   if not both: return results
 
   missing = []
   for filename in idl_files:
     if filename not in set(h_files):
@@ skipping 59 matching lines @@
             'Missing PPAPI IDL for private interface, please generate IDL:',
             long_text='\n'.join(missing_priv)))
 
   if missing_dev:
     results.append(
         output_api.PresubmitPromptWarning(
             'Missing PPAPI IDL for DEV, required before moving to stable:',
             long_text='\n'.join(missing_dev)))
 
   if missing_stable:
-    results.append(
-        output_api.PresubmitError(
-            'Missing PPAPI IDL for stable interface:',
-            long_text='\n'.join(missing_stable)))
+    # It might be okay that the header changed without a corresponding IDL
+    # change. E.g., comment indenting may have been changed. Treat this as a
+    # warning.
+    if generators_changed:
+      results.append(
+          output_api.PresubmitPromptWarning(
+              'Missing PPAPI IDL for stable interface (due to change in ' +
+              'generators?):',
+              long_text='\n'.join(missing_stable)))
+    else:
+      results.append(
+          output_api.PresubmitError(
+              'Missing PPAPI IDL for stable interface:',
+              long_text='\n'.join(missing_stable)))
 
   # Verify all *.h files match *.idl definitions, use:
   #   --test to prevent output to disk
   #   --diff to generate a unified diff
   #   --out to pick which files to examine (only the ones in the CL)
   ppapi_dir = input_api.PresubmitLocalPath()
   cmd = [sys.executable, 'generator.py',
          '--wnone', '--diff', '--test','--cgen', '--range=start,end']
 
   # Only generate output for IDL files references (as *.h or *.idl) in this CL
   cmd.append('--out=' + ','.join([name + '.idl' for name in both]))
   cmd_results = RunCmdAndCheck(cmd,
                                'PPAPI IDL Diff detected: Run the generator.',
                                output_api,
                                os.path.join(ppapi_dir, 'generators'))
   if cmd_results:
     results.extend(cmd_results)
 
   return results
 
 
 def CheckChangeOnUpload(input_api, output_api):
   return CheckChange(input_api, output_api)
 
 
 def CheckChangeOnCommit(input_api, output_api):
   return CheckChange(input_api, output_api)