From 17d990542eb83db05aca76cc369ff4af6fcfd7ae Mon Sep 17 00:00:00 2001
From: KS Chan <mrkschan@gmail.com>
Date: Thu, 13 Dec 2018 22:33:24 +0800
Subject: [PATCH] Handle invalid ref that pretends to be a sub-folder under a
 valid ref

---
 dulwich/refs.py            | 2 +-
 dulwich/tests/test_refs.py | 7 +++++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/dulwich/refs.py b/dulwich/refs.py
index 7c44bd5f..000bb515 100644
--- a/dulwich/refs.py
+++ b/dulwich/refs.py
@@ -617,7 +617,7 @@ class DiskRefsContainer(RefsContainer):
                     # Read only the first 40 bytes
                     return header + f.read(40 - len(SYMREF))
         except IOError as e:
-            if e.errno in (errno.ENOENT, errno.EISDIR):
+            if e.errno in (errno.ENOENT, errno.EISDIR, errno.ENOTDIR):
                 return None
             raise
 
diff --git a/dulwich/tests/test_refs.py b/dulwich/tests/test_refs.py
index e1b03664..2898f1a3 100644
--- a/dulwich/tests/test_refs.py
+++ b/dulwich/tests/test_refs.py
@@ -486,6 +486,13 @@ class DiskRefsContainerTests(RefsContainerTests, TestCase):
                          self._refs.read_ref(b'refs/heads/packed'))
         self.assertEqual(None, self._refs.read_ref(b'nonexistant'))
 
+    def test_read_loose_ref(self):
+        self._refs[b'refs/heads/foo'] = (
+            b'df6800012397fb85c56e7418dd4eb9405dee075c'
+        )
+
+        self.assertEqual(None, self._refs.read_ref(b'refs/heads/foo/bar'))
+
     def test_non_ascii(self):
         try:
             encoded_ref = u'refs/tags/schön'.encode(
-- 
2.34.1