From eba15d128b3765f044be2a2308f108f7b11985bc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Sch=C3=BCrmann?= <daschuer@mixxx.org>
Date: Sun, 11 Jul 2021 07:59:33 +0200
Subject: [PATCH] Split get_git_dir() into get_git_dir() and
 get_git_common_dir()

This fixes the conflicted state check when using work trees. #1972
---
 pre_commit/commands/install_uninstall.py |  2 +-
 pre_commit/git.py                        | 23 +++++++++++++++++------
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/pre_commit/commands/install_uninstall.py b/pre_commit/commands/install_uninstall.py
index 73c8d605..6f7aa4a2 100644
--- a/pre_commit/commands/install_uninstall.py
+++ b/pre_commit/commands/install_uninstall.py
@@ -40,7 +40,7 @@ def _hook_paths(
         hook_type: str,
         git_dir: Optional[str] = None,
 ) -> Tuple[str, str]:
-    git_dir = git_dir if git_dir is not None else git.get_git_dir()
+    git_dir = git_dir if git_dir is not None else git.get_git_common_dir()
     pth = os.path.join(git_dir, 'hooks', hook_type)
     return pth, f'{pth}.legacy'
 
diff --git a/pre_commit/git.py b/pre_commit/git.py
index 4bf28235..bbdcd38d 100644
--- a/pre_commit/git.py
+++ b/pre_commit/git.py
@@ -55,7 +55,7 @@ def get_root() -> str:
         root = os.path.abspath(
             cmd_output('git', 'rev-parse', '--show-cdup')[1].strip(),
         )
-        git_dir = os.path.abspath(get_git_dir())
+        git_dir = os.path.abspath(get_git_common_dir())
     except CalledProcessError:
         raise FatalError(
             'git failed. Is it installed, and are you in a Git repository '
@@ -70,15 +70,26 @@ def get_root() -> str:
 
 
 def get_git_dir(git_root: str = '.') -> str:
-    opts = ('--git-common-dir', '--git-dir')
-    _, out, _ = cmd_output('git', 'rev-parse', *opts, cwd=git_root)
-    for line, opt in zip(out.splitlines(), opts):
-        if line != opt:  # pragma: no branch (git < 2.5)
-            return os.path.normpath(os.path.join(git_root, line))
+    opt = '--git-dir'
+    _, out, _ = cmd_output('git', 'rev-parse', opt, cwd=git_root)
+    git_dir = out.strip()
+    if git_dir != opt:
+        return os.path.normpath(os.path.join(git_root, git_dir))
     else:
         raise AssertionError('unreachable: no git dir')
 
 
+def get_git_common_dir(git_root: str = '.') -> str:
+    opt = '--git-common-dir'
+    _, out, _ = cmd_output('git', 'rev-parse', opt, cwd=git_root)
+    git_common_dir = out.strip()
+    if git_common_dir != opt:
+        return os.path.normpath(os.path.join(git_root, git_common_dir))
+    else:
+        # pragma: no branch (git < 2.5)
+        return get_git_dir(git_root)
+
+
 def get_remote_url(git_root: str) -> str:
     _, out, _ = cmd_output('git', 'config', 'remote.origin.url', cwd=git_root)
     return out.strip()