Add unit test to ensure we don't diff bare repos

Resolves #38502.

tests/unit/states/test_git.py

@@ -0,0 +1,84 @@
+# -*- coding: utf-8 -*-
+'''
+    :codeauthor: Erik Johnson <erik@saltstack.com>
+'''
+
+# Import Python libs
+from __future__ import absolute_import
+import logging
+import os
+
+# Import Salt Testing Libs
+from tests.support.helpers import with_tempdir
+from tests.support.mixins import LoaderModuleMockMixin
+from tests.support.unit import TestCase, skipIf
+from tests.support.mock import (
+    Mock,
+    MagicMock,
+    patch,
+    DEFAULT,
+    NO_MOCK,
+    NO_MOCK_REASON,
+)
+
+# Import Salt Libs
+import salt.states.git as git_state  # Don't potentially shadow GitPython
+
+log = logging.getLogger(__name__)
+
+
+@skipIf(NO_MOCK, NO_MOCK_REASON)
+class GitTestCase(TestCase, LoaderModuleMockMixin):
+    '''
+    Test cases for salt.states.git
+    '''
+    def setup_loader_modules(self):
+        return {
+            git_state: {
+                '__env__': 'base',
+                '__opts__': {'test': False},
+                '__salt__': {},
+            }
+        }
+
+    @with_tempdir()
+    def test_latest_no_diff_for_bare_repo(self, target):
+        '''
+        This test ensures that we don't attempt to diff when cloning a repo
+        using either bare=True or mirror=True.
+        '''
+        name = 'https://foo.com/bar/baz.git'
+        gitdir = os.path.join(target, 'refs')
+        isdir_mock = MagicMock(
+            side_effect=lambda path: DEFAULT if path != gitdir else True)
+
+        branches = ['foo', 'bar', 'baz']
+        tags = ['v1.1.0', 'v.1.1.1', 'v1.2.0']
+        local_head = 'b9ef06ab6b7524eb7c27d740dbbd5109c6d75ee4'
+        remote_head = 'eef672c1ec9b8e613905dbcd22a4612e31162807'
+
+        git_diff = Mock()
+        dunder_salt = {
+            'git.current_branch': MagicMock(return_value=branches[0]),
+            'git.diff': git_diff,
+            'git.fetch': MagicMock(return_value={}),
+            'git.is_worktree': MagicMock(return_value=False),
+            'git.list_branches': MagicMock(return_value=branches),
+            'git.list_tags': MagicMock(return_value=tags),
+            'git.remote_refs': MagicMock(return_value={'HEAD': remote_head}),
+            'git.remotes': MagicMock(return_value={
+                'origin': {'fetch': name, 'push': name},
+            }),
+            'git.rev_parse': MagicMock(side_effect=git_state.CommandExecutionError()),
+            'git.revision': MagicMock(return_value=local_head),
+            'git.version': MagicMock(return_value='1.8.3.1'),
+        }
+        with patch('os.path.isdir', isdir_mock), \
+                patch.dict(git_state.__salt__, dunder_salt):
+            result = git_state.latest(
+                name=name,
+                target=target,
+                mirror=True,  # mirror=True implies bare=True
+            )
+            assert result['result'] is True, result
+            git_diff.assert_not_called()