feat: require live PR head re-pin before conflict-fix classification (Closes #522)

Treat inventory mergeable/head as advisory. Add classification helper and MCP tool so author sessions re-pin the live PR head before creating a conflict-fix worktree, skip stale inventory false-negatives, and prove classification in final reports.
2026-07-08 22:30:21 -04:00
parent 81822da04d
commit add87b5708
7 changed files with 505 additions and 1 deletions
@@ -0,0 +1,142 @@
+"""Tests for live PR head re-pin before conflict-fix classification (#522)."""
+
+from __future__ import annotations
+
+import unittest
+
+from conflict_fix_classification import (
+    CLASSIFICATION_CONFLICT_FIX_NEEDED,
+    CLASSIFICATION_INCOMPLETE,
+    CLASSIFICATION_LIVE_MERGEABLE,
+    CLASSIFICATION_STALE_INVENTORY_SKIP,
+    assess_conflict_fix_classification,
+    assess_conflict_fix_classification_final_report,
+)
+
+
+def _sha(prefix: str) -> str:
+    return (prefix + "0" * 40)[:40]
+
+
+class TestConflictFixClassification(unittest.TestCase):
+    def test_stale_inventory_mergeable_skip(self):
+        """PR #508 style: inventory mergeable:false/stale head, live mergeable:true."""
+        result = assess_conflict_fix_classification(
+            pr_number=508,
+            inventory_head_sha=_sha("dad1dc8"),
+            inventory_mergeable=False,
+            live_head_sha=_sha("3f3d6cb"),
+            live_mergeable=True,
+        )
+        self.assertEqual(result["classification"], CLASSIFICATION_STALE_INVENTORY_SKIP)
+        self.assertTrue(result["skip_author_mutation"])
+        self.assertFalse(result["worktree_allowed"])
+        self.assertTrue(result["inventory_stale_head"])
+        self.assertTrue(result["inventory_stale_mergeable"])
+        self.assertEqual(result["pinned_head_sha"], _sha("3f3d6cb"))
+
+    def test_stale_inventory_head_only_live_mergeable_true(self):
+        """PR #493 style: head moved; live still mergeable."""
+        result = assess_conflict_fix_classification(
+            pr_number=493,
+            inventory_head_sha=_sha("685e627"),
+            inventory_mergeable=True,
+            live_head_sha=_sha("4561d7a"),
+            live_mergeable=True,
+        )
+        self.assertEqual(result["classification"], CLASSIFICATION_STALE_INVENTORY_SKIP)
+        self.assertTrue(result["skip_author_mutation"])
+        self.assertFalse(result["worktree_allowed"])
+        self.assertTrue(result["inventory_stale_head"])
+        self.assertEqual(result["pinned_head_sha"], _sha("4561d7a"))
+
+    def test_live_conflict_allows_worktree_on_pinned_head(self):
+        result = assess_conflict_fix_classification(
+            pr_number=99,
+            inventory_head_sha=_sha("aaaaaaa"),
+            inventory_mergeable=False,
+            live_head_sha=_sha("bbbbbbb"),
+            live_mergeable=False,
+        )
+        self.assertEqual(result["classification"], CLASSIFICATION_CONFLICT_FIX_NEEDED)
+        self.assertTrue(result["worktree_allowed"])
+        self.assertFalse(result["skip_author_mutation"])
+        self.assertTrue(result["inventory_stale_head"])
+        self.assertEqual(result["pinned_head_sha"], _sha("bbbbbbb"))
+
+    def test_matching_inventory_live_mergeable_skip(self):
+        head = _sha("cccccccc")
+        result = assess_conflict_fix_classification(
+            pr_number=10,
+            inventory_head_sha=head,
+            inventory_mergeable=True,
+            live_head_sha=head,
+            live_mergeable=True,
+        )
+        self.assertEqual(result["classification"], CLASSIFICATION_LIVE_MERGEABLE)
+        self.assertFalse(result["worktree_allowed"])
+        self.assertTrue(result["skip_author_mutation"])
+        self.assertFalse(result["inventory_stale_head"])
+
+    def test_missing_live_head_incomplete(self):
+        result = assess_conflict_fix_classification(
+            pr_number=1,
+            inventory_head_sha=_sha("ddddddd"),
+            inventory_mergeable=False,
+            live_head_sha=None,
+            live_mergeable=False,
+        )
+        self.assertEqual(result["classification"], CLASSIFICATION_INCOMPLETE)
+        self.assertFalse(result["worktree_allowed"])
+        self.assertTrue(result["skip_author_mutation"])
+        self.assertTrue(any("live PR head" in r for r in result["reasons"]))
+
+    def test_short_sha_rejected(self):
+        result = assess_conflict_fix_classification(
+            pr_number=1,
+            inventory_head_sha="abc1234",
+            inventory_mergeable=False,
+            live_head_sha="def5678",
+            live_mergeable=False,
+        )
+        self.assertEqual(result["classification"], CLASSIFICATION_INCOMPLETE)
+        self.assertFalse(result["worktree_allowed"])
+
+
+class TestConflictFixClassificationFinalReport(unittest.TestCase):
+    def test_non_conflict_report_not_applicable(self):
+        result = assess_conflict_fix_classification_final_report(
+            "Implemented feature without merge issues."
+        )
+        self.assertTrue(result["proven"])
+        self.assertFalse(result["applicable"])
+
+    def test_conflict_report_requires_tool_live_head_classification(self):
+        result = assess_conflict_fix_classification_final_report(
+            "Did conflict-fix work on PR #99."
+        )
+        self.assertFalse(result["proven"])
+        self.assertTrue(result["applicable"])
+        joined = " ".join(result["reasons"])
+        self.assertIn("gitea_assess_conflict_fix_classification", joined)
+        self.assertIn("Live head SHA", joined)
+        self.assertIn("classification", joined.lower())
+
+    def test_good_conflict_report_passes(self):
+        live = _sha("3f3d6cb")
+        inv = _sha("dad1dc8")
+        text = f"""
+Conflict-fix classification: stale_inventory_skip
+Called gitea_assess_conflict_fix_classification before worktree creation.
+Inventory head SHA: {inv}
+Live head SHA: {live}
+Use live head only; skip author mutation.
+"""
+        result = assess_conflict_fix_classification_final_report(text)
+        self.assertTrue(result["proven"], msg=result.get("reasons"))
+        self.assertEqual(result["live_head_sha"], live)
+        self.assertEqual(result["inventory_head_sha"], inv)
+
+
+if __name__ == "__main__":
+    unittest.main()