Merge pull request #4622 from ctiller/dep_head

Add ability to update submodules before build

tools/run_tests/run_tests.py

@@ -1,5 +1,5 @@
 #!/usr/bin/env python2.7
-# Copyright 2015, Google Inc.
+# Copyright 2015-2016, Google Inc.
 # All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
@@ -646,6 +646,9 @@ argp.add_argument('--build_only',
                   action='store_const',
                   const=True,
                   help='Perform all the build steps but dont run any tests.')
+argp.add_argument('--update_submodules', default=[], nargs='*',
+                  help='Update some submodules before building. If any are updated, also run generate_projects. ' +
+                       'Submodules are specified as SUBMODULE_NAME:BRANCH; if BRANCH is omitted, master is assumed.')
 argp.add_argument('-a', '--antagonists', default=0, type=int)
 argp.add_argument('-x', '--xml_report', default=None, type=str,
         help='Generates a JUnit-compatible XML report')
@@ -681,6 +684,26 @@ if args.use_docker:
                         env=env)
   sys.exit(0)
 
+# update submodules if necessary
+if args.update_submodules:
+  for spec in args.update_submodules:
+    spec = spec.split(':', 1)
+    if len(spec) == 1:
+      submodule = spec[0]
+      branch = 'master'
+    elif len(spec) == 2:
+      submodule = spec[0]
+      branch = spec[1]
+    cwd = 'third_party/%s' % submodule
+    def git(cmd, cwd=cwd):
+      print 'in %s: git %s' % (cwd, cmd)
+      subprocess.check_call('git %s' % cmd, cwd=cwd, shell=True)
+    git('fetch')
+    git('checkout %s' % branch)
+    git('pull origin %s' % branch)
+  subprocess.check_call('tools/buildgen/generate_projects.sh', shell=True)
+
+
 # grab config
 run_configs = set(_CONFIGS[cfg]
                   for cfg in itertools.chain.from_iterable(
@@ -692,7 +715,7 @@ if args.travis:
   _FORCE_ENVIRON_FOR_WRAPPERS = {'GRPC_TRACE': 'api'}
 
 if 'all' in args.language:
-  lang_list = _LANGUAGES.keys()  
+  lang_list = _LANGUAGES.keys()
 else:
   lang_list = args.language
 # We don't support code coverage on ObjC