tests: don't leak files/descriptors when tests finish (#9119)

close open files/descriptors when tests finish

tests/func/test_lock.py

@@ -15,7 +15,7 @@ def test_with(tmp_dir, dvc, mocker):
             pass
 
 
-def test_unlock_lock_failed(tmp_dir, dvc, mocker):
+def test_unlock_lock_failed(tmp_dir, dvc, request, mocker):
     # patching to speedup tests
     mocker.patch("dvc.lock.DEFAULT_TIMEOUT", 0.01)
 
@@ -28,6 +28,7 @@ def test_unlock_lock_failed(tmp_dir, dvc, mocker):
     with lock:
         lock.unlock()
         lock_ext.lock()  # imitate an exernal process had time to lock it
+        request.addfinalizer(lock_ext.unlock)
         with pytest.raises(LockError):
             lock.lock()
 

tests/unit/proc/test_process.py

@@ -23,14 +23,17 @@ def mock_popen(mocker):
         ["/bin/foo", "-o", "option"],
     ],
 )
-def test_init_args(tmp_dir, args, mocker):
+def test_init_args(tmp_dir, request, args, mocker):
     expected = ["/bin/foo", "-o", "option"]
     proc = ManagedProcess(args)
+    request.addfinalizer(proc._close_fds)
     assert expected == proc.args
 
 
-def test_run(tmp_dir, mocker):
+def test_run(tmp_dir, request, mocker):
     proc = ManagedProcess("/bin/foo")
+
+    request.addfinalizer(proc._close_fds)
     assert proc.pid == TEST_PID
 
     with open(proc.info_path, encoding="utf-8") as fobj: