contest: fetcher: fix old branch cleanup

We are accumulating branches on all runners, the cleanup must not
be working. It's most likely because we forgot to set the cwd.
Make sure we check if the commands failed.

Signed-off-by: Jakub Kicinski <[email protected]>

Author: kuba-moo

contest/remote/lib/fetcher.py

@@ -105,13 +105,18 @@ def _run_test(self, binfo):
         self._result_set(binfo['branch'], url)
 
     def _clean_old_branches(self, remote, current):
-        ret = subprocess.run('git branch', shell=True, capture_output=True)
+        ret = subprocess.run('git branch',
+                             cwd=self._tree_path, shell=True,
+                             capture_output=True, check=True)
+
         existing = set([x.strip() for x in ret.stdout.decode('utf-8').split('\n')])
 
         for b in remote:
             if b["branch"] in existing and b["branch"] != current:
-                subprocess.run('git branch -d ' + b["branch"],
-                               cwd=self._tree_path, shell=True)
+                print("Clean up old branch", b["branch"])
+                subprocess.run('git branch -D ' + b["branch"],
+                               cwd=self._tree_path, shell=True,
+                               check=True)
 
     def _run_once(self):
         r = requests.get(self._branches_url)