alternate vcs: Fix unitests

Author: cdevienne

src/towncrier/_vcs.py

@@ -12,10 +12,12 @@ def _get_mod(base_directory: str):
         from . import _hg
 
         return _hg
-    else:
+    elif base_directory == "/":
         from . import _novcs
 
         return _novcs
+    else:
+        return _get_mod(os.path.dirname(base_directory))
 
 
 def get_default_compare_branch(

src/towncrier/test/test_check.py

@@ -401,24 +401,6 @@ def test_get_default_compare_branch_missing(self):
         self.assertEqual(1, result.exit_code)
         self.assertEqual("Could not detect default branch. Aborting.\n", result.output)
 
-    def test_get_default_compare_branch_main(self):
-        """
-        If there's a remote branch origin/main, prefer it over everything else.
-        """
-        branch = check._get_default_compare_branch(["origin/master", "origin/main"])
-
-        self.assertEqual("origin/main", branch)
-
-    def test_get_default_compare_branch_fallback(self):
-        """
-        If there's origin/master and no main, use it and warn about it.
-        """
-        with warnings.catch_warnings(record=True) as w:
-            branch = check._get_default_compare_branch(["origin/master", "origin/foo"])
-
-        self.assertEqual("origin/master", branch)
-        self.assertTrue(w[0].message.args[0].startswith('Using "origin/master'))
-
     @with_isolated_runner
     def test_in_different_dir_with_nondefault_newsfragments_directory(self, runner):
         """
@@ -429,8 +411,7 @@ def test_in_different_dir_with_nondefault_newsfragments_directory(self, runner):
         Path("pyproject.toml").write_text(
             # Important to customize `config.directory` because the default
             # already supports this scenario.
-            "[tool.towncrier]\n"
-            + 'directory = "changelog.d"\n'
+            "[tool.towncrier]\n" + 'directory = "changelog.d"\n'
         )
         subproject1 = Path("foo")
         (subproject1 / "foo").mkdir(parents=True)

src/towncrier/test/test_git.py

@@ -5,6 +5,7 @@
 from twisted.trial.unittest import TestCase
 
 from towncrier import _git
+import warnings
 
 
 class TestGit(TestCase):
@@ -13,3 +14,21 @@ def test_empty_remove(self):
         If remove_files gets an empty list, it returns gracefully.
         """
         _git.remove_files([])
+
+    def test_get_default_compare_branch_main(self):
+        """
+        If there's a remote branch origin/main, prefer it over everything else.
+        """
+        branch = _git.get_default_compare_branch(["origin/master", "origin/main"])
+
+        self.assertEqual("origin/main", branch)
+
+    def test_get_default_compare_branch_fallback(self):
+        """
+        If there's origin/master and no main, use it and warn about it.
+        """
+        with warnings.catch_warnings(record=True) as w:
+            branch = _git.get_default_compare_branch(["origin/master", "origin/foo"])
+
+        self.assertEqual("origin/master", branch)
+        self.assertTrue(w[0].message.args[0].startswith('Using "origin/master'))