Presubmit recipe: call presubmit_support.py directly

For some reason, presubmit_support.py can't find PRESUBMIT.py
unless it has a diff. Calling this script directly allows us
to specify a fake upstream to force it to find a diff and
therefore be able to find PRESUBMIT.py.

BUG=skia:5823
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2398653002

Review-Url: https://codereview.chromium.org/2398653002

2 files changed, 16 insertions, 69 deletions

diff --git a/infra/bots/recipes/swarm_presubmit.expected/presubmit.json b/infra/bots/recipes/swarm_presubmit.expected/presubmit.json
index 6eb60133a1..5e88fc3353 100644
--- a/infra/bots/recipes/swarm_presubmit.expected/presubmit.json
+++ b/infra/bots/recipes/swarm_presubmit.expected/presubmit.json
@@ -122,16 +122,6 @@
   {
     "cmd": [
       "git",
-      "checkout",
-      "-b",
-      "tmp_00000000-0000-0000-0000-000000000000"
-    ],
-    "cwd": "[CUSTOM_/_B_WORK]/skia",
-    "name": "create git branch"
-  },
-  {
-    "cmd": [
-      "git",
       "status"
     ],
     "cwd": "[CUSTOM_/_B_WORK]/skia",
@@ -139,10 +129,9 @@
   },
   {
     "cmd": [
-      "git",
-      "cl",
-      "presubmit",
-      "--force",
+      "RECIPE_PACKAGE_REPO[depot_tools]/presubmit_support.py",
+      "--commit",
+      "--upstream=HEAD^",
       "-v",
       "-v"
     ],
@@ -153,35 +142,6 @@
     "name": "presubmit"
   },
   {
-    "cmd": [
-      "git",
-      "reset",
-      "--hard",
-      "origin/master"
-    ],
-    "cwd": "[CUSTOM_/_B_WORK]/skia",
-    "name": "git reset"
-  },
-  {
-    "cmd": [
-      "git",
-      "checkout",
-      "origin/master"
-    ],
-    "cwd": "[CUSTOM_/_B_WORK]/skia",
-    "name": "checkout origin/master"
-  },
-  {
-    "cmd": [
-      "git",
-      "branch",
-      "-D",
-      "tmp_00000000-0000-0000-0000-000000000000"
-    ],
-    "cwd": "[CUSTOM_/_B_WORK]/skia",
-    "name": "delete git branch"
-  },
-  {
     "name": "$result",
     "recipe_result": null,
     "status_code": 0
diff --git a/infra/bots/recipes/swarm_presubmit.py b/infra/bots/recipes/swarm_presubmit.py
index ad4802501f..84d82231e8 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):