Correctly propagate "permission denied" error on creating directory

- fixes #507

CHANGES.md

@@ -16,6 +16,10 @@ the proposed changes so you can be ready.
 #### New Features
   * Added support for handling keyword-only arguments in some `os` functions
 
+#### Fixes
+  * Fixed behavior of `os.makedirs` in write-protected directory 
+    (see [#507](../../issues/507))
+
 ## [Version 3.7](https://pypi.python.org/pypi/pyfakefs/3.7)
 
 This version adds support for Python 3.8.

pyfakefs/fake_filesystem.py

@@ -2854,6 +2854,9 @@ def makedirs(self, dir_name, mode=PERM_DEF, exist_ok=False):
         try:
             self.create_dir(dir_name, mode & ~self.umask)
         except (IOError, OSError) as e:
+            if e.errno == errno.EACCES:
+                # permission denied - propagate exception
+                raise
             if (not exist_ok or
                     not isinstance(self.resolve(dir_name), FakeDirectory)):
                 if self.is_windows_fs and e.errno == errno.ENOTDIR:

pyfakefs/tests/fake_os_test.py

@@ -1694,6 +1694,20 @@ def test_makedirs_exist_ok(self):
         self.os.makedirs(directory, exist_ok=True)
         self.assertTrue(self.os.path.exists(directory))
 
+    def test_makedirs_in_write_protected_dir(self):
+        self.check_posix_only()
+        directory = self.make_path('foo')
+        self.os.mkdir(directory, mode=0o555)
+        subdir = self.os.path.join(directory, 'bar')
+        if not is_root():
+            self.assert_raises_os_error(errno.EACCES, self.os.makedirs,
+                                        subdir, exist_ok=True)
+            self.assert_raises_os_error(errno.EACCES, self.os.makedirs,
+                                        subdir, exist_ok=False)
+        else:
+            self.os.makedirs(subdir)
+            self.assertTrue(self.os.path.exists(subdir))
+
     # test fsync and fdatasync
     def test_fsync_raises_on_non_int(self):
         self.assertRaises(TypeError, self.os.fsync, "zero")