Presubmit recipe: commit the patch

infra/bots/recipes/swarm_presubmit.py

Index: infra/bots/recipes/swarm_presubmit.py
diff --git a/infra/bots/recipes/swarm_presubmit.py b/infra/bots/recipes/swarm_presubmit.py
index ad4802501f53bd4a86d81bde5c97c9537f598557..84d82231e83e5bd2c7ee498e17b0ea489a0e55ab 100644
--- a/infra/bots/recipes/swarm_presubmit.py
+++ b/infra/bots/recipes/swarm_presubmit.py
@@ -21,33 +21,20 @@ def RunSteps(api):
   api.vars.setup()
   api.core.checkout_steps()
 
-  # git-cl wants us to be on a branch.
-  branch = 'tmp_%s' % api.uuid.random()
-  api.step('create git branch',
-           cmd=['git', 'checkout', '-b', branch],
+  api.step('git status',
+           cmd=['git', 'status'],
            cwd=api.vars.skia_dir)
-  try:
-    api.step('git status',
-             cmd=['git', 'status'],
-             cwd=api.vars.skia_dir)
-
-    depot_tools_path = api.depot_tools.package_repo_resource()
-    env = {'PATH': api.path.pathsep.join([str(depot_tools_path), '%(PATH)s'])}
-    api.step('presubmit',
-             cmd=['git', 'cl', 'presubmit', '--force', '-v', '-v'],
-             cwd=api.vars.skia_dir,
-             env=env)
-  finally:
-    api.step('git reset',
-             cmd=['git', 'reset', '--hard', 'origin/master'],
-             cwd=api.vars.skia_dir)
-    api.step('checkout origin/master',
-             cmd=['git', 'checkout', 'origin/master'],
-             cwd=api.vars.skia_dir)
-    api.step('delete git branch',
-             cmd=['git', 'branch', '-D', branch],
-             cwd=api.vars.skia_dir)
-             
+
+  depot_tools_path = api.depot_tools.package_repo_resource()
+  script = depot_tools_path.join('presubmit_support.py')
+  env = {'PATH': api.path.pathsep.join([str(depot_tools_path), '%(PATH)s'])}
+  # TODO(borenet): --upstream=HEAD^ is a hack to force presubmit_support to
+  # find a diff. Otherwise, it quits early with:
+  #  "Warning, no PRESUBMIT.py found."
+  api.step('presubmit',
+           cmd=[script, '--commit', '--upstream=HEAD^', '-v', '-v'],
+           cwd=api.vars.skia_dir,
+           env=env)
 
 
 def GenTests(api):