Scope the No-Check-Posted Cause to DIRTY and Give It a Remedy

scripts/README.md

@@ -205,7 +205,7 @@ uv run --no-project --script scripts/pr_review.py cleanup 452 --repo ptr727/Proj
 | `41` | `wait` | The newest round is a refusal or a quota state, its kind printed in the status line, and in `refusal=` for a refusal on this pull request. |
 | `42` | `status`, `wait` | The round covering the head states partial coverage. Or a non-refusal head round exists while an earlier round states partial, and one reads `UNKNOWN` or none states coverage. |
 | `44` | `wait` | The review loop closed, the merge reads `BLOCKED`, and a required check is in a shape no wait clears. |
-| `45` | `wait` | An open attested held head that nothing holds, its merge other than `CLEAN`, `UNSTABLE`, or `HAS_HOOKS`. Its rollup was unreadable or none posted, or a `DIRTY` or `BEHIND` merge lacks a required check or has it from another app, judged on rules read and a whole rollup. |
+| `45` | `wait` | An open attested held head that nothing holds, its merge other than `CLEAN`, `UNSTABLE`, or `HAS_HOOKS`. Its rollup was unreadable, a `DIRTY` merge has none posted, or a `DIRTY` or `BEHIND` merge lacks a required check or has it from another app, judged on rules read and a whole rollup. |
 | `49` | `wait` | No Copilot round covers the head and none was requested, on a pull request into a branch other than the default with no attestation. |
 | `50` | `status`, `wait` | The round covering the head opens on a verdict other than the clean one while it counts no finding. Or a head round carries a part the reader cannot place, and nothing acknowledges its fingerprint. |
 | `60` to `63` | `reply` | No thread matched, more than one did, the reply returned no comment url, or the resolve did not report the thread resolved. |

scripts/pr_review.py

@@ -118,10 +118,11 @@
            workflow run the read reaches on that head has then completed. The read reaches the
            head's last 50 check suites and those of its first CHECKS_WINDOW rollup contexts. A
            CLEAN, UNSTABLE, or HAS_HOOKS merge owes no required check. Under any other merge, an
-           open attested held head nothing holds exits 45 where its rollup was unreadable or none
-           posted. A DIRTY or BEHIND one also exits 45 where a required check is unregistered or
-           from another app. Exit 0 can then leave a required check unregistered only under unread
-           rules, a `CHECKS TRUNCATED` rollup, a DRAFT merge, or a pull request not open.
+           open attested held head nothing holds exits 45 where its rollup was unreadable or, under
+           DIRTY, none posted. A DIRTY or BEHIND one also exits 45 where a required check is
+           unregistered or from another app. Exit 0 can then leave a required check unregistered
+           only under unread rules, a `CHECKS TRUNCATED` rollup, a DRAFT merge, or a pull request
+           not open.
            30 = still pending at the timeout. On a held head it is any hold
            `status=CHECKS_PENDING` names, a required check still settling and a workflow run still
            open among them. Where the rollup holds a type this cannot read, a BLOCKED hold's note
@@ -143,11 +144,11 @@
            a held head a check running long or held by its environment polls to 30 instead.
            45 = an open attested held head that nothing holds, its merge other than CLEAN,
            UNSTABLE, or HAS_HOOKS. Either the payload carries no commit matching the head, named
-           `CHECKS UNREADABLE` in the digest, or no check has posted. Or the merge reads DIRTY or
-           BEHIND and a check the base branch's rules require has not registered, or came from
-           another app. That last needs the rules read and a rollup not `CHECKS TRUNCATED`. Where
-           the rollup holds a type this cannot read, named `CHECKS PARTIALLY UNREAD` in the
-           digest, the status says the check may sit there.
+           `CHECKS UNREADABLE` in the digest, or a DIRTY merge has no check posted. Or the merge
+           reads DIRTY or BEHIND and a check the base branch's rules require has not registered,
+           or came from another app. That last needs the rules read and a rollup not
+           `CHECKS TRUNCATED`. Where the rollup holds a type this cannot read, named
+           `CHECKS PARTIALLY UNREAD` in the digest, the status says the check may sit there.
            `status=CHECKS_MISSING` names which. A DIRTY merge runs no pull_request workflow until
            its conflict is resolved. A required check not yet registered holds a BLOCKED merge to
            30 instead, where the rules and the head's rollup were read, not `CHECKS TRUNCATED`. An

scripts/pr_review_checks.py

@@ -311,7 +311,10 @@ def checks_never_ran(
     if checks_unreadable(pr):
         return "the payload carries no commit matching the head, so read the check runs on the head commit"
     if not nodes:
-        return "no check has posted, and a DIRTY merge runs no pull_request workflow until resolved"
+        return (
+            "no check has posted, so resolve the head's conflict with its base, since a DIRTY "
+            "merge runs no pull_request workflow until then"
+        )
     unmet = ", ".join(required_unregistered(pr, nodes, required))
     unread = checks_unread(nodes)
     where = ", sits in the rollup's unread part," if unread else ""

tests/test_pr_review.py

@@ -3592,7 +3592,10 @@ def test_an_empty_rollup_holds_any_merge_but_a_conflicted_one(self) -> None:
                     self.assertEqual(code, self.cli(["wait", "7", "--timeout", "0"]))
                 if code == 45:
                     self.assertIn("status=CHECKS_MISSING", self.out.getvalue())
-                    self.assertIn("but no check has posted", self.out.getvalue())
+                    self.assertIn(
+                        "but no check has posted, so resolve the head's conflict",
+                        self.out.getvalue(),
+                    )
 
     def test_an_optional_check_does_not_hold_once_the_required_gate_concluded(self) -> None:
         """A merge BLOCKED on a thread is not waiting on a check nothing requires."""
@@ -3742,7 +3745,8 @@ def test_a_released_head_exits_by_what_its_read_shows(self) -> None:
                 self.wire_history([hist_review(7, OVERVIEW + "\n" + COVERED)])
                 with mock.patch.object(pr_review.time, "sleep"):
                     self.assertEqual(code, self.cli(["wait", "7", "--timeout", "1"]))
-                self.assertIn(reason, self.out.getvalue())
+                if reason:
+                    self.assertIn(reason, self.out.getvalue())
                 if label == "another app":
                     self.assertNotIn("checks and statuses first", self.out.getvalue())
                 if code == 0: