Add test that raises TypeError in git.execute(..., output_stream=file)

Author: Dmitry Nikulin

Diff for: git/test/test_git.py

@@ -7,6 +7,7 @@
 import os
 import subprocess
 import sys
+from tempfile import TemporaryFile
 
 from git import (
     Git,
@@ -108,6 +109,11 @@ def test_it_ignores_false_kwargs(self, git):
         self.git.version(pass_this_kwarg=False)
         assert_true("pass_this_kwarg" not in git.call_args[1])
 
+    @raises(GitCommandError)
+    def test_it_raises_proper_exception_with_output_stream(self):
+        tmp_file = TemporaryFile()
+        self.git.checkout('non-existent-branch', output_stream=tmp_file)
+
     def test_it_accepts_environment_variables(self):
         filename = fixture_path("ls_tree_empty")
         with open(filename, 'r') as fh: