test: gold files shouldn't be ignored

I made a private copy of this repo to check something, and xml gold
tests were failing because my new private repo didn't have the
coverage.xml gold files, because they were in .gitignore.

.gitignore

@@ -7,12 +7,14 @@
 *.bak
 .coverage
 .coverage.*
-coverage.xml
-coverage.json
 .metacov
 .metacov.*
 *.swp
 
+# Data files we should ignore in the root, but need for gold files.
+/coverage.xml
+/coverage.json
+
 # Stuff generated by editors.
 .idea/
 .vscode/

Makefile

@@ -32,7 +32,8 @@ clean: clean_platform			## Remove artifacts of test execution, installation, etc
 	@rm -f *.bak */*.bak */*/*.bak */*/*/*.bak */*/*/*/*.bak */*/*/*/*/*.bak
 	@rm -f coverage/*,cover
 	@rm -f MANIFEST
-	@rm -f .coverage .coverage.* coverage.xml coverage.json .metacov*
+	@rm -f .coverage .coverage.* .metacov*
+	@rm -f coverage.xml coverage.json
 	@rm -f .tox/*/lib/*/site-packages/zzz_metacov.pth
 	@rm -f */.coverage */*/.coverage */*/*/.coverage */*/*/*/.coverage */*/*/*/*/.coverage */*/*/*/*/*/.coverage
 	@rm -f tests/covmain.zip tests/zipmods.zip tests/zip1.zip

tests/goldtest.py

@@ -99,9 +99,9 @@ def save_mismatch(f: str) -> None:
 
     assert not text_diff, "Files differ: " + "\n".join(text_diff)
 
-    assert not expected_only, f"Files in {expected_dir} only: {expected_only}"
+    assert not expected_only, f"Files in {os.path.abspath(expected_dir)} only: {expected_only}"
     if not actual_extra:
-        assert not actual_only, f"Files in {actual_dir} only: {actual_only}"
+        assert not actual_only, f"Files in {os.path.abspath(actual_dir)} only: {actual_only}"
 
 
 def contains(filename: str, *strlist: str) -> None:

tests/test_goldtest.py

@@ -105,7 +105,8 @@ def test_actual_extra(self) -> None:
         compare(gold_path("testing/getty"), "out", scrubs=SCRUBS, actual_extra=True)
 
         # But not without it:
-        msg = r"Files in out only: \['another.more'\]"
+        # (test output is in files like /tmp/pytest-of-user/pytest-0/popen-gw3/t76/out)
+        msg = r"Files in .*[/\\]t\d+[/\\]out only: \['another.more'\]"
         with pytest.raises(AssertionError, match=msg):
             compare(gold_path("testing/getty"), "out", scrubs=SCRUBS)
         self.assert_exists(os.path.join(TESTS_DIR, "actual/testing/getty/another.more"))