Merge pull request #6532 from blueyed/harden-test

--cache-clear: add test for keeping non-supporting files

testing/test_cacheprovider.py

@@ -268,9 +268,11 @@ class TestLastFailed:
                 "*1 failed*2 passed*",
             ]
         )
+        testdir.tmpdir.join(".pytest_cache").mkdir(".git")
         result = testdir.runpytest(str(p), "--lf", "--cache-clear")
         result.stdout.fnmatch_lines(["*1 failed*2 passed*"])
         assert testdir.tmpdir.join(".pytest_cache", "README.md").isfile()
+        assert testdir.tmpdir.join(".pytest_cache", ".git").isdir()
 
         # Run this again to make sure clear-cache is robust
         if os.path.isdir(".pytest_cache"):