chore(golden): satisfy ruff PLR2004 + black on new fix-up tests

Pull magic numbers (rename change count, argparse usage exit code) into
named constants, and let black collapse the adjacent-string formatting
on the new parser tests.

Author: bnusunny

tests/golden/test_check_semver_bump.py

@@ -6,6 +6,9 @@
 
 from tests.golden import check_semver_bump as csb
 
+# A rename emits one D + one A change.
+_RENAME_CHANGE_COUNT = 2
+
 
 def test_no_changes_passes():
     rc, msg = csb.check(
@@ -80,23 +83,21 @@ def test_parser_rename_emits_delete_plus_add(monkeypatch):
     split into a deletion of OLD and an addition of NEW so the gate sees
     the source go away."""
     fake_diff = (
-        "R100\ttests/golden/templates/x/old/expected.build.yaml"
-        "\ttests/golden/templates/x/new/expected.build.yaml\n"
+        "R100\ttests/golden/templates/x/old/expected.build.yaml" "\ttests/golden/templates/x/new/expected.build.yaml\n"
     )
     monkeypatch.setattr(csb.subprocess, "check_output", lambda *a, **kw: fake_diff)
     changes = csb._git_changed_files("base", "head")
     assert csb.Change("tests/golden/templates/x/old/expected.build.yaml", "D") in changes
     assert csb.Change("tests/golden/templates/x/new/expected.build.yaml", "A") in changes
-    assert len(changes) == 2
+    assert len(changes) == _RENAME_CHANGE_COUNT
 
 
 def test_parser_copy_treated_as_addition_only(monkeypatch):
     """A `C<score>\\tOLD\\tNEW` line means the source still exists, only
     the new target is added. The gate must classify this as A only — not
     let it silently bypass via an unrecognized "C" status."""
     fake_diff = (
-        "C100\ttests/golden/templates/x/old/expected.build.yaml"
-        "\ttests/golden/templates/x/new/expected.build.yaml\n"
+        "C100\ttests/golden/templates/x/old/expected.build.yaml" "\ttests/golden/templates/x/new/expected.build.yaml\n"
     )
     monkeypatch.setattr(csb.subprocess, "check_output", lambda *a, **kw: fake_diff)
     changes = csb._git_changed_files("base", "head")
@@ -112,8 +113,7 @@ def test_copy_of_existing_pin_does_not_bypass_gate(monkeypatch):
     addition — feeding only A's through `check()` correctly returns 0,
     but the path must NOT be silently dropped."""
     fake_diff = (
-        "C100\ttests/golden/templates/x/old/expected.build.yaml"
-        "\ttests/golden/templates/x/new/expected.build.yaml\n"
+        "C100\ttests/golden/templates/x/old/expected.build.yaml" "\ttests/golden/templates/x/new/expected.build.yaml\n"
     )
     monkeypatch.setattr(csb.subprocess, "check_output", lambda *a, **kw: fake_diff)
     changes = csb._git_changed_files("base", "head")

tests/golden/test_update_goldens.py

@@ -9,6 +9,9 @@
 
 REPO_CASES = Path(__file__).parent / "templates"
 
+# argparse's parser.error() exits with status 2 (Unix convention for usage error).
+_ARGPARSE_USAGE_ERROR = 2
+
 
 @pytest.fixture
 def isolated_corpus(tmp_path, monkeypatch):
@@ -110,6 +113,6 @@ def test_check_and_diff_are_mutually_exclusive(capsys):
     checks."""
     with pytest.raises(SystemExit) as excinfo:
         update_goldens.main(["--check", "--diff"])
-    assert excinfo.value.code == 2  # argparse parser.error exits 2
+    assert excinfo.value.code == _ARGPARSE_USAGE_ERROR
     err = capsys.readouterr().err
     assert "--check and --diff are mutually exclusive" in err