Fix exception when Git has a broken ref

CHANGELOG.md

@@ -1,3 +1,8 @@
+## Unreleased
+
+* Fixed an exception when a Git repository had a broken ref.
+  Git would print a warning that Dunamai failed to parse.
+
 ## v1.19.1 (2024-02-07)
 
 * Relaxed Python bounds from `^3.5` to `>=3.5` since Python does not follow Semantic Versioning.

dunamai/__init__.py

@@ -1184,6 +1184,8 @@ def from_git(
 
             for line in msg.strip().splitlines():
                 parts = line.split("@{")
+                if len(parts) != 5:
+                    continue
                 detailed_tags.append(_GitRefInfo(*parts).with_tag_topo_lookup(tag_topo_lookup))
 
             tags = [t.ref for t in sorted(detailed_tags, key=lambda x: x.sort_key, reverse=True)]

tests/integration/test_dunamai.py

@@ -491,6 +491,24 @@ def test__version__from_git__exclude_decoration(tmp_path) -> None:
         assert from_vcs() == Version("0.1.0", dirty=False, branch=b)
 
 
+def test__version__from_git__broken_ref(tmp_path) -> None:
+    vcs = tmp_path / "dunamai-git-broken-ref"
+    vcs.mkdir()
+    run = make_run_callback(vcs)
+    from_vcs = make_from_callback(Version.from_git)
+    b = "master"
+
+    with chdir(vcs):
+        run("git init")
+        (vcs / "foo.txt").write_text("hi")
+        run("git add .")
+        run("git commit --no-gpg-sign -m Initial")
+        run("git tag v0.1.0 -m Release")
+        (vcs / ".git/refs/tags/bad.txt").touch()
+
+        assert from_vcs() == Version("0.1.0", dirty=False, branch=b)
+
+
 @pytest.mark.skipif(shutil.which("git") is None, reason="Requires Git")
 def test__version__not_a_repository(tmp_path) -> None:
     vcs = tmp_path / "dunamai-not-a-repo"