feat(release): add retry mode to re-deploy existing release without re-tagging

Recovers from a release whose tag+commit landed cleanly but whose
post-tag steps (git push, latest-tag bump, twine upload) failed
mid-flight. pkgmgr release --retry skips the version bump, file
rewrites, commit, and tag-creation steps and re-runs only the
idempotent tail: re-push the existing HEAD tag, re-align the floating
latest tag, and (unless --no-publish) re-invoke publish.

The retry logic lives in its own module pkgmgr.actions.release.retry
so the workflow.py orchestrator stays focused on the forward path.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tests/unit/pkgmgr/actions/release/test_retry.py

@@ -0,0 +1,154 @@
+"""Unit tests for the `release(retry=True)` re-deploy entry point.
+
+`TestReleaseRetry` exercises the routing decision in `release()` —
+that `--retry` skips the full `_release_impl` flow and dispatches to
+`retry_release` instead.
+
+`TestRetryRelease` exercises the standalone module `pkgmgr.actions.release.retry`:
+HEAD-tag discovery, idempotent push, latest-tag re-alignment, and
+fallback behaviour when the current branch cannot be detected.
+"""
+
+from __future__ import annotations
+
+import unittest
+from unittest.mock import patch
+
+from pkgmgr.actions.release.retry import retry_release
+from pkgmgr.actions.release.workflow import release
+from pkgmgr.core.git import GitRunError
+
+
+class TestReleaseRetry(unittest.TestCase):
+    @patch("pkgmgr.actions.release.workflow.retry_release")
+    @patch("pkgmgr.actions.release.workflow._release_impl")
+    def test_retry_routes_to_retry_release_only(
+        self, mock_release_impl, mock_retry_release
+    ) -> None:
+        release(retry=True, preview=False)
+
+        mock_retry_release.assert_called_once()
+        mock_release_impl.assert_not_called()
+        self.assertFalse(mock_retry_release.call_args.kwargs["preview"])
+
+    @patch("pkgmgr.actions.release.workflow.retry_release")
+    @patch("pkgmgr.actions.release.workflow._release_impl")
+    def test_retry_preview_passthrough(
+        self, mock_release_impl, mock_retry_release
+    ) -> None:
+        release(retry=True, preview=True)
+
+        mock_retry_release.assert_called_once()
+        mock_release_impl.assert_not_called()
+        self.assertTrue(mock_retry_release.call_args.kwargs["preview"])
+
+    @patch("pkgmgr.actions.release.workflow.retry_release")
+    @patch("pkgmgr.actions.release.workflow._release_impl")
+    def test_retry_ignores_release_args(
+        self, mock_release_impl, mock_retry_release
+    ) -> None:
+        # release_type/message/close/force must NOT trigger the full release flow
+        # when retry=True.
+        release(
+            retry=True,
+            release_type="major",
+            message="ignored body",
+            preview=False,
+            force=True,
+            close=True,
+        )
+
+        mock_retry_release.assert_called_once()
+        mock_release_impl.assert_not_called()
+
+
+class TestRetryRelease(unittest.TestCase):
+    @patch("pkgmgr.actions.release.retry.update_latest_tag")
+    @patch("pkgmgr.actions.release.retry.is_highest_version_tag", return_value=True)
+    @patch("pkgmgr.actions.release.retry.run")
+    @patch("pkgmgr.actions.release.retry.head_semver_tags")
+    @patch(
+        "pkgmgr.actions.release.retry.get_current_branch",
+        return_value="release-fix",
+    )
+    def test_retry_pushes_existing_tag_and_updates_latest(
+        self,
+        _mock_branch,
+        mock_head_tags,
+        mock_run,
+        _mock_highest,
+        mock_update_latest,
+    ) -> None:
+        mock_head_tags.return_value = ["v1.13.4"]
+
+        retry_release(pyproject_path="pyproject.toml", preview=False)
+
+        mock_run.assert_called_once_with(
+            ["push", "origin", "release-fix", "v1.13.4"], preview=False
+        )
+        mock_update_latest.assert_called_once_with("v1.13.4", preview=False)
+
+    @patch("pkgmgr.actions.release.retry.update_latest_tag")
+    @patch("pkgmgr.actions.release.retry.is_highest_version_tag", return_value=False)
+    @patch("pkgmgr.actions.release.retry.run")
+    @patch("pkgmgr.actions.release.retry.head_semver_tags")
+    @patch(
+        "pkgmgr.actions.release.retry.get_current_branch",
+        return_value="release-fix",
+    )
+    def test_retry_skips_latest_for_non_highest_tag(
+        self,
+        _mock_branch,
+        mock_head_tags,
+        _mock_run,
+        _mock_highest,
+        mock_update_latest,
+    ) -> None:
+        mock_head_tags.return_value = ["v1.0.0"]
+
+        retry_release(pyproject_path="pyproject.toml", preview=False)
+
+        mock_update_latest.assert_not_called()
+
+    @patch(
+        "pkgmgr.actions.release.retry.head_semver_tags",
+        return_value=[],
+    )
+    @patch(
+        "pkgmgr.actions.release.retry.get_current_branch",
+        return_value="main",
+    )
+    def test_retry_raises_when_head_has_no_tag(
+        self, _mock_branch, _mock_head_tags
+    ) -> None:
+        with self.assertRaises(RuntimeError) as cm:
+            retry_release(pyproject_path="pyproject.toml", preview=False)
+        self.assertIn("No version tag on HEAD", str(cm.exception))
+
+    @patch("pkgmgr.actions.release.retry.update_latest_tag")
+    @patch("pkgmgr.actions.release.retry.is_highest_version_tag", return_value=True)
+    @patch("pkgmgr.actions.release.retry.run")
+    @patch("pkgmgr.actions.release.retry.head_semver_tags")
+    @patch(
+        "pkgmgr.actions.release.retry.get_current_branch",
+        side_effect=GitRunError("detached"),
+    )
+    def test_retry_falls_back_to_main_branch_when_detection_fails(
+        self,
+        _mock_branch,
+        mock_head_tags,
+        mock_run,
+        _mock_highest,
+        _mock_update_latest,
+    ) -> None:
+        mock_head_tags.return_value = ["v2.0.0"]
+
+        retry_release(pyproject_path="pyproject.toml", preview=False)
+
+        mock_run.assert_called_once_with(
+            ["push", "origin", "main", "v2.0.0"], preview=False
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()