split up the tests

tests/conftest.py

@@ -0,0 +1,18 @@
+import os
+from unittest import mock
+
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def xdg_data_home(tmpdir):
+    data_home = tmpdir.join('data_home')
+    with mock.patch.dict(os.environ, {'XDG_DATA_HOME': str(data_home)}):
+        yield data_home
+
+
+@pytest.fixture
+def ten_lines(tmpdir):
+    f = tmpdir.join('f')
+    f.write('\n'.join(f'line_{i}' for i in range(10)))
+    yield f