Expose local branch ref as an environment variable

pre_commit/commands/hook_impl.py

@@ -70,6 +70,7 @@ def _ns(
         *,
         all_files: bool = False,
         remote_branch: Optional[str] = None,
+        local_branch: Optional[str] = None,
         from_ref: Optional[str] = None,
         to_ref: Optional[str] = None,
         remote_name: Optional[str] = None,
@@ -82,6 +83,7 @@ def _ns(
         color=color,
         hook_stage=hook_type.replace('pre-', ''),
         remote_branch=remote_branch,
+        local_branch=local_branch,
         from_ref=from_ref,
         to_ref=to_ref,
         remote_name=remote_name,
@@ -110,14 +112,15 @@ def _pre_push_ns(
     remote_url = args[1]
 
     for line in stdin.decode().splitlines():
-        _, local_sha, remote_branch, remote_sha = line.split()
+        local_branch, local_sha, remote_branch, remote_sha = line.split()
         if local_sha == Z40:
             continue
         elif remote_sha != Z40 and _rev_exists(remote_sha):
             return _ns(
                 'pre-push', color,
                 from_ref=remote_sha, to_ref=local_sha,
                 remote_branch=remote_branch,
+                local_branch=local_branch,
                 remote_name=remote_name, remote_url=remote_url,
             )
         else:
@@ -139,6 +142,7 @@ def _pre_push_ns(
                         all_files=True,
                         remote_name=remote_name, remote_url=remote_url,
                         remote_branch=remote_branch,
+                        local_branch=local_branch,
                     )
                 else:
                     rev_cmd = ('git', 'rev-parse', f'{first_ancestor}^')
@@ -148,6 +152,7 @@ def _pre_push_ns(
                         from_ref=source, to_ref=local_sha,
                         remote_name=remote_name, remote_url=remote_url,
                         remote_branch=remote_branch,
+                        local_branch=local_branch,
                     )
 
     # nothing to push

pre_commit/commands/run.py

@@ -371,7 +371,11 @@ def run(
         environ['PRE_COMMIT_FROM_REF'] = args.from_ref
         environ['PRE_COMMIT_TO_REF'] = args.to_ref
 
-    if args.remote_name and args.remote_url and args.remote_branch:
+    if (
+        args.remote_name and args.remote_url and
+        args.remote_branch and args.local_branch
+    ):
+        environ['PRE_COMMIT_LOCAL_BRANCH'] = args.local_branch
         environ['PRE_COMMIT_REMOTE_BRANCH'] = args.remote_branch
         environ['PRE_COMMIT_REMOTE_NAME'] = args.remote_name
         environ['PRE_COMMIT_REMOTE_URL'] = args.remote_url

pre_commit/main.py

@@ -99,6 +99,9 @@ def _add_run_options(parser: argparse.ArgumentParser) -> None:
     parser.add_argument(
         '--remote-branch', help='Remote branch ref used by `git push`.',
     )
+    parser.add_argument(
+        '--local-branch', help='Local branch ref used by `git push`.',
+    )
     parser.add_argument(
         '--from-ref', '--source', '-s',
         help=(

testing/util.py

@@ -62,6 +62,7 @@ def run_opts(
         verbose=False,
         hook=None,
         remote_branch='',
+        local_branch='',
         from_ref='',
         to_ref='',
         remote_name='',
@@ -81,6 +82,7 @@ def run_opts(
         verbose=verbose,
         hook=hook,
         remote_branch=remote_branch,
+        local_branch=local_branch,
         from_ref=from_ref,
         to_ref=to_ref,
         remote_name=remote_name,

tests/commands/run_test.py

@@ -487,6 +487,7 @@ def test_all_push_options_ok(cap_out, store, repo_with_passing_hook):
     args = run_opts(
         from_ref='master', to_ref='master',
         remote_branch='master',
+        local_branch='master',
         remote_name='origin', remote_url='https://example.com/repo',
     )
     ret, printed = _do_run(cap_out, store, repo_with_passing_hook, args)