diff --git a/git/repo/base.py b/git/repo/base.py
index 9cdf673e6..238095415 100644
--- a/git/repo/base.py
+++ b/git/repo/base.py
@@ -123,9 +123,9 @@ class Repo(object):
     DAEMON_EXPORT_FILE = "git-daemon-export-ok"
 
     git = cast("Git", None)  # Must exist, or  __del__  will fail in case we raise on `__init__()`
-    working_dir: Optional[PathLike] = None
+    working_dir: PathLike
     _working_tree_dir: Optional[PathLike] = None
-    git_dir: PathLike = ""
+    git_dir: PathLike
     _common_dir: PathLike = ""
 
     # precompiled regex
@@ -215,13 +215,14 @@ def __init__(
         ## Walk up the path to find the `.git` dir.
         #
         curpath = epath
+        git_dir = None
         while curpath:
             # ABOUT osp.NORMPATH
             # It's important to normalize the paths, as submodules will otherwise initialize their
             # repo instances with paths that depend on path-portions that will not exist after being
             # removed. It's just cleaner.
             if is_git_dir(curpath):
-                self.git_dir = curpath
+                git_dir = curpath
                 # from man git-config : core.worktree
                 # Set the path to the root of the working tree. If GIT_COMMON_DIR environment
                 # variable is set, core.worktree is ignored and not used for determining the
@@ -230,7 +231,7 @@ def __init__(
                 # directory, which is either specified by GIT_DIR, or automatically discovered.
                 # If GIT_DIR is specified but none of GIT_WORK_TREE and core.worktree is specified,
                 # the current working directory is regarded as the top level of your working tree.
-                self._working_tree_dir = os.path.dirname(self.git_dir)
+                self._working_tree_dir = os.path.dirname(git_dir)
                 if os.environ.get("GIT_COMMON_DIR") is None:
                     gitconf = self.config_reader("repository")
                     if gitconf.has_option("core", "worktree"):
@@ -242,14 +243,14 @@ def __init__(
             dotgit = osp.join(curpath, ".git")
             sm_gitpath = find_submodule_git_dir(dotgit)
             if sm_gitpath is not None:
-                self.git_dir = osp.normpath(sm_gitpath)
+                git_dir = osp.normpath(sm_gitpath)
 
             sm_gitpath = find_submodule_git_dir(dotgit)
             if sm_gitpath is None:
                 sm_gitpath = find_worktree_git_dir(dotgit)
 
             if sm_gitpath is not None:
-                self.git_dir = expand_path(sm_gitpath, expand_vars)
+                git_dir = expand_path(sm_gitpath, expand_vars)
                 self._working_tree_dir = curpath
                 break
 
@@ -260,8 +261,9 @@ def __init__(
                 break
         # END while curpath
 
-        if self.git_dir is None:
+        if git_dir is None:
             raise InvalidGitRepositoryError(epath)
+        self.git_dir = git_dir
 
         self._bare = False
         try:
@@ -282,7 +284,7 @@ def __init__(
             self._working_tree_dir = None
         # END working dir handling
 
-        self.working_dir: Optional[PathLike] = self._working_tree_dir or self.common_dir
+        self.working_dir: PathLike = self._working_tree_dir or self.common_dir
         self.git = self.GitCommandWrapperType(self.working_dir)
 
         # special handling, in special times
@@ -320,7 +322,7 @@ def close(self) -> None:
                 gc.collect()
 
     def __eq__(self, rhs: object) -> bool:
-        if isinstance(rhs, Repo) and self.git_dir:
+        if isinstance(rhs, Repo):
             return self.git_dir == rhs.git_dir
         return False
 
@@ -332,14 +334,12 @@ def __hash__(self) -> int:
 
     # Description property
     def _get_description(self) -> str:
-        if self.git_dir:
-            filename = osp.join(self.git_dir, "description")
+        filename = osp.join(self.git_dir, "description")
         with open(filename, "rb") as fp:
             return fp.read().rstrip().decode(defenc)
 
     def _set_description(self, descr: str) -> None:
-        if self.git_dir:
-            filename = osp.join(self.git_dir, "description")
+        filename = osp.join(self.git_dir, "description")
         with open(filename, "wb") as fp:
             fp.write((descr + "\n").encode(defenc))
 
@@ -357,13 +357,7 @@ def common_dir(self) -> PathLike:
         """
         :return: The git dir that holds everything except possibly HEAD,
             FETCH_HEAD, ORIG_HEAD, COMMIT_EDITMSG, index, and logs/."""
-        if self._common_dir:
-            return self._common_dir
-        elif self.git_dir:
-            return self.git_dir
-        else:
-            # or could return ""
-            raise InvalidGitRepositoryError()
+        return self._common_dir or self.git_dir
 
     @property
     def bare(self) -> bool: