individual run evidence, retained summaries, and trend comparison

tests/test_core.py

@@ -14,7 +14,8 @@ from guide_board.planning import (
     validate_assessment_profile,
     validate_target_profile,
 )
-from guide_board.retention import list_retained_runs
+from guide_board.retention import build_trend_summary, list_retained_runs
+from guide_board.schema import assert_valid
 
 
 ROOT = Path(__file__).resolve().parents[1]
@@ -106,6 +107,44 @@ class CoreArchitectureTests(unittest.TestCase):
             self.assertEqual(len(mappings), 1)
             self.assertEqual(mappings[0]["target_id"], "profile-readiness")
 
+    def test_builds_retained_run_trends(self) -> None:
+        with TemporaryDirectory() as temporary_directory:
+            runs_dir = Path(temporary_directory)
+            _write_retention_summary(
+                runs_dir / "run-old",
+                "run-old",
+                "2026-05-07T10:00:00+00:00",
+                "blocked",
+                {"blocked": 1},
+                1,
+                1,
+            )
+            _write_retention_summary(
+                runs_dir / "run-new",
+                "run-new",
+                "2026-05-07T11:00:00+00:00",
+                "completed",
+                {"manual": 1, "skipped": 1},
+                0,
+                2,
+            )
+
+            trend = build_trend_summary(runs_dir)
+            assert_valid(trend, "trend-summary")
+
+            self.assertEqual(trend["run_count"], 2)
+            self.assertEqual(len(trend["groups"]), 1)
+            group = trend["groups"][0]
+            self.assertEqual(group["latest_run"]["run_id"], "run-new")
+            self.assertEqual(group["previous_run"]["run_id"], "run-old")
+            self.assertEqual(group["trend"]["direction"], "improved")
+            self.assertTrue(group["trend"]["status_changed"])
+            self.assertEqual(group["trend"]["unexpected_findings_delta"], -1)
+            self.assertEqual(
+                group["trend"]["evidence_result_deltas"],
+                {"blocked": -1, "manual": 1, "skipped": 1},
+            )
+
     def test_runs_cmis_preflight_against_local_endpoint(self) -> None:
         server = HTTPServer(("127.0.0.1", 0), _CmisHandler)
         thread = threading.Thread(target=server.serve_forever)
@@ -469,5 +508,49 @@ class _CmisHandler(BaseHTTPRequestHandler):
         return
 
 
+def _write_retention_summary(
+    run_dir: Path,
+    run_id: str,
+    created_at: str,
+    status: str,
+    evidence_results: dict[str, int],
+    unexpected_findings: int,
+    artifact_count: int,
+) -> None:
+    run_dir.mkdir(parents=True, exist_ok=True)
+    (run_dir / "retention-summary.json").write_text(
+        json.dumps(
+            {
+                "id": f"retention-summary:{run_id}",
+                "run_id": run_id,
+                "target_profile_ref": "sample-repository",
+                "assessment_profile_ref": "sample-noop-assessment",
+                "created_at": created_at,
+                "summary": {
+                    "status": status,
+                    "evidence_results": evidence_results,
+                    "finding_count": unexpected_findings,
+                    "unexpected_findings": unexpected_findings,
+                    "expected_findings": 0,
+                    "waived_findings": 0,
+                    "mapping_target_count": 1,
+                    "artifact_count": artifact_count,
+                },
+                "report_refs": [
+                    "reports/assessment-package.json",
+                    "reports/report.md",
+                ],
+                "artifact_retention": {
+                    "policy": {"raw_artifact_days": 0, "summary_days": 365},
+                    "output_artifact_retention": "summary-only",
+                    "retention_class_counts": {"raw": artifact_count},
+                    "raw_artifact_count": artifact_count,
+                },
+            }
+        ),
+        encoding="utf-8",
+    )
+
+
 if __name__ == "__main__":
     unittest.main()