fix(scm-provider): prefer full version over floating tags

Motivation: With tags v1.0.0, v1.0 and v1 on one commit, the scm version
provider returned "1.0". The three versions compare equal, and max()
kept the first one, which is the newest tag by date. The patch part was
dropped from the project version.

Approach: Break ties between equal versions by choosing the longest
spelling, so 1.0.0 wins over 1.0 and 1. Ordering of unequal versions is
unchanged.

Validation: `uv run pytest -n0` passed (1331 passed, 2 skipped,
2 xfailed). The new test fails without the change and passes with it.
`ruff check`, `ruff format --check` and `mypy commitizen/providers`
pass. `uv run poe all` was not run in full.

Impact: Only affects `version_provider = "scm"` when equal-valued tags
with different lengths exist. Only the version printed or used was
wrong; nothing else changed.

Report: #1863

Assisted By: AI

Signed-off-by: Pujitha Paladugu <10557236+pujitha24@users.noreply.github.com>
Assisted-by: claude-sonnet-5-5 (via Claude Code)

Author: pujitha24

commitizen/providers/scm_provider.py

@@ -18,7 +18,13 @@ def get_version(self) -> str:
         rules = TagRules.from_settings(self.config.settings)
         tags = get_tags(reachable_only=True)
         version_tags = rules.get_version_tags(tags)
-        version = max((rules.extract_version(t) for t in version_tags), default=None)
+        # Floating tags (e.g. `v1.0` next to `v1.0.0`) compare equal. Among equal
+        # versions, prefer the most specific (longest) spelling.
+        version = max(
+            (rules.extract_version(t) for t in version_tags),
+            key=lambda v: (v, len(str(v))),
+            default=None,
+        )
         return str(version) if version is not None else "0.0.0"
 
     def set_version(self, version: str) -> None:

tests/providers/test_scm_provider.py

@@ -140,3 +140,23 @@ def test_scm_provider_detect_legacy_tags(config: BaseConfig, util: UtilFixture):
     util.create_file_and_commit("test: fake commit")
     util.create_tag("v0.5.0")
     assert provider.get_version() == "0.5.0"
+
+
+@pytest.mark.usefixtures("tmp_git_project")
+def test_scm_provider_prefers_full_version_over_floating_tags(
+    config: BaseConfig, util: UtilFixture
+):
+    """Floating tags (`v1.0`, `v1`) must not hide the full `v1.0.0` version."""
+    # Arrange
+    util.create_file_and_commit("feat: initial commit")
+    util.create_tag("v1.0.0")
+    util.create_tag("v1.0")
+    util.create_tag("v1")
+    config.settings["version_provider"] = "scm"
+    config.settings["tag_format"] = "v$version"
+
+    # Act
+    provider = get_provider(config)
+
+    # Assert
+    assert provider.get_version() == "1.0.0"