TST: don't assume test user is OS user

mock getpwnam to always return result for current user

since test user may well no exist

In particular, JupyterHub 5 test utilities no longer create a test user with the running user's name

batchspawner/tests/test_spawners.py

@@ -1,8 +1,11 @@
 """Test BatchSpawner and subclasses"""
 
 import asyncio
+import os
+import pwd
 import re
 import time
+from unittest import mock
 
 import pytest
 from jupyterhub import orm
@@ -17,6 +20,15 @@
 testport = 54321
 
 
+@pytest.fixture(autouse=True)
+def _always_get_my_home():
+    # pwd.getbwnam() is always called with the current user
+    # ignoring the requested name, which usually doesn't exist
+    getpwnam = pwd.getpwnam
+    with mock.patch.object(pwd, "getpwnam", lambda name: getpwnam(os.getlogin())):
+        yield
+
+
 class BatchDummy(BatchSpawnerRegexStates):
     exec_prefix = ""
     batch_submit_cmd = Unicode("cat > /dev/null; echo " + testjob)