Use a cache dir in the cwd on CI

kitty_tests/__init__.py

@@ -2,6 +2,7 @@
 # vim:fileencoding=utf-8
 # License: GPL v3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
 
+import os
 from unittest import TestCase
 
 from kitty.config import Options, defaults, merge_configs
@@ -81,6 +82,7 @@ class BaseTest(TestCase):
 
     ae = TestCase.assertEqual
     maxDiff = 2000
+    is_ci = os.environ.get('CI') == 'true'
 
     def set_options(self, options=None):
         final_options = {'scrollback_pager_history_size': 1024, 'click_interval': 0.5}

kitty_tests/graphics.py

@@ -180,10 +180,10 @@ def make_send_command(screen):
 class TestGraphics(BaseTest):
 
     def setUp(self):
-        self.cache_dir = cache_dir.override_dir = tempfile.mkdtemp()
+        cache_dir.override_dir = tempfile.mkdtemp(dir=os.getcwd() if self.is_ci else None)
 
     def tearDown(self):
-        os.rmdir(self.cache_dir)
+        os.rmdir(cache_dir.override_dir)
         cache_dir.override_dir = None
 
     def test_xor_data(self):