headless: Ensure all commands have parameters and return types

headless/lib/browser/client_api_generator.py

 # 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.
 
 import argparse
 import os.path
 import sys
 import re
 try:
   import json
@@ skipping 355 matching lines @@
   Mark all commands and events in experimental domains as experimental
   and make sure experimental commands have at least empty parameters
   and return values.
   """
   for domain in json_api['domains']:
     if domain.get('experimental', False):
       for command in domain.get('commands', []):
         command['experimental'] = True
       for event in domain.get('events', []):
         event['experimental'] = True
+
+
+def EnsureCommandsHaveParametersAndReturnTypes(json_api):
+  """
+  Make sure all commands have at least empty parameters and return values. This
+  guarantees API compatibility if a previously experimental command is made
+  stable.
+  """
+  for domain in json_api['domains']:
     for command in domain.get('commands', []):
-      if not command.get('experimental', False):
-        continue
       if not 'parameters' in command:
         command['parameters'] = []
       if not 'returns' in command:
         command['returns'] = []
     for event in domain.get('events', []):
-      if not event.get('experimental', False):
-        continue
       if not 'parameters' in event:
         event['parameters'] = []
 
 
 def Generate(jinja_env, output_dirname, json_api, class_name, file_types):
   template_context = {
     'api': json_api,
     'join_arrays': JoinArrays,
     'resolve_type': ResolveType,
     'type_definition': TypeDefinition,
@@ skipping 19 matching lines @@
       domain_name = CamelCaseToHackerStyle(domain['domain'])
       output_file = '%s/%s.%s' % (output_dirname, domain_name, file_type)
       with open(output_file, 'w') as f:
         f.write(template.render(template_context))
 
 
 if __name__ == '__main__':
   json_api, output_dirname = ParseArguments(sys.argv[1:])
   jinja_env = InitializeJinjaEnv(output_dirname)
   PatchExperimentalCommandsAndEvents(json_api)
+  EnsureCommandsHaveParametersAndReturnTypes(json_api)
   SynthesizeCommandTypes(json_api)
   SynthesizeEventTypes(json_api)
   PatchFullQualifiedRefs(json_api)
   CreateTypeDefinitions(json_api)
   Generate(jinja_env, output_dirname, json_api, 'types', ['cc', 'h'])
   Generate(jinja_env, output_dirname, json_api, 'type_conversions', ['h'])
   GenerateDomains(jinja_env, output_dirname, json_api, 'domain', ['cc', 'h'])