feat(ci): draft contributor PRs until review-readiness checklist is complete

.github/scripts/enforce-pr-target.test.cjs

@@ -48,10 +48,11 @@ describe("enforce-pr-target workflow", () => {
     assert.match(workflow, /synchronize/);
   });
 
-  it("checks out trusted default-branch scripts only (never PR head)", () => {
+  it("checks out trusted base-branch scripts only (never PR head)", () => {
     assert.match(workflow, /actions\/checkout@[0-9a-f]{40}/);
-    assert.match(workflow, /ref:\s*\$\{\{\s*github\.event\.repository\.default_branch\s*\}\}/);
-    assert.match(workflow, /sparse-checkout:\s*\.github\/scripts/);
+    assert.match(workflow, /ref:\s*\$\{\{\s*github\.event\.pull_request\.base\.ref\s*\}\}/);
+    // The readiness ping reads MAINTAINERS.md from the same trusted checkout.
+    assert.match(workflow, /sparse-checkout:\s*\|\s*\n\s*\.github\/scripts\n\s*MAINTAINERS\.md/);
     assert.match(workflow, /persist-credentials:\s*false/);
     assert.doesNotMatch(workflow, /ref:\s*\$\{\{\s*github\.event\.pull_request\.head/);
   });
@@ -75,9 +76,9 @@ describe("enforce-pr-target workflow", () => {
 
   it("strips stale WRONG BRANCH prefix on failure when base is corrected", () => {
     const failureBlock = workflow.match(
-      /if \(failures\.length > 0\) \{([\s\S]*?)core\.setFailed\(/,
+      /if \(mustDraft\) \{([\s\S]*?)core\.setFailed\(/,
     );
-    assert.ok(failureBlock, "workflow must have a failure path");
+    assert.ok(failureBlock, "workflow must have a draft path");
     const failurePath = failureBlock[1];
     assert.match(failurePath, /shouldStripTitlePrefix/);
     assert.match(failurePath, /!hasWrongBase/);

.github/scripts/pr-quality.cjs

@@ -15,6 +15,22 @@ const MIN_RICH_SECTIONS = 2;
 const UNSTRUCTURED_MIN_LEN = 120;
 const UNSTRUCTURED_MIN_BLOCKS = 2;
 
+/** HTML markers bounding the bot-managed review-readiness checklist in the PR body. */
+const REVIEW_READINESS_START = "<!-- pr-quality-readiness-checklist:start -->";
+const REVIEW_READINESS_END = "<!-- pr-quality-readiness-checklist:end -->";
+
+/**
+ * The four self-attestation boxes a non-maintainer author must tick before the
+ * gate lifts the draft. The final box is intentionally set off by a blank line
+ * so the "ready" claim reads as the closing confirmation, not a fourth task.
+ */
+const REVIEW_READINESS_ITEMS = [
+  "All CI tests are green on my local testing.",
+  "I pushed my PR to the latest dev commit.",
+  "I fixed all correct Codex and CodeRabbit findings.",
+  "My PR is ready for review.",
+];
+
 /**
  * Exact instruction / checklist lines from `.github/PULL_REQUEST_TEMPLATE.md`.
  * Untouched templates must not count as substance.
@@ -109,13 +125,14 @@ function stripPrTemplateBoilerplate(text) {
 }
 
 function assessPrDescription(body) {
-  if (typeof body !== "string" || !body.trim()) {
+  const withoutReadiness = stripReviewReadinessSection(body);
+  if (typeof withoutReadiness !== "string" || !withoutReadiness.trim()) {
     return { ok: false, reason: "empty" };
   }
-  if (hasEscapedNewlines(body)) {
+  if (hasEscapedNewlines(withoutReadiness)) {
     return { ok: false, reason: "escaped_newlines" };
   }
-  const withoutTemplate = stripPrTemplateBoilerplate(body);
+  const withoutTemplate = stripPrTemplateBoilerplate(withoutReadiness);
   const cleaned = clean(withoutTemplate);
   if (!cleaned) {
     const strippedComments = withoutTemplate.replace(/<!--[\s\S]*?-->/g, "").trim();
@@ -191,6 +208,101 @@ function hasScreenshotEvidence(body) {
   return hasRenderableReferenceImage(visible);
 }
 
+/**
+ * The tickable checklist section injected into the PR description. It lives in
+ * the body (the author can tick it) and is bounded by HTML markers so the gate
+ * can find exactly this section and ignore any other task list in the body.
+ */
+function buildReviewReadinessSection() {
+  const items = REVIEW_READINESS_ITEMS.flatMap((item, index) =>
+    index === REVIEW_READINESS_ITEMS.length - 1
+      ? ["", `- [ ] ${item}`]
+      : [`- [ ] ${item}`],
+  );
+  return [
+    REVIEW_READINESS_START,
+    "## Review readiness checklist",
+    "",
+    "This PR stays in draft until every box below is ticked. Tick all four boxes once the requirements are met:",
+    "",
+    ...items,
+    REVIEW_READINESS_END,
+  ].join("\n");
+}
+
+/**
+ * Read the checklist section the bot manages. `present` means the marker pair
+ * exists; `complete` means the section contains exactly the four boxes and all
+ * of them are checked. Anything else (missing markers, fewer or extra boxes,
+ * unchecked boxes) keeps the gate closed. The author can reword an item, but
+ * the box count and the checked state are the contract.
+ */
+function extractReviewReadiness(body) {
+  if (typeof body !== "string") {
+    return {
+      present: false,
+      complete: false,
+      checked: 0,
+      total: 0,
+      items: [],
+    };
+  }
+  const start = body.indexOf(REVIEW_READINESS_START);
+  const end = body.indexOf(REVIEW_READINESS_END);
+  // Any marker presence counts as present: an author-edited section that is
+  // inverted or partial must never trigger another append, or every `edited`
+  // event would stack a second checklist (and a second body write).
+  if (start === -1 || end === -1 || end <= start) {
+    return {
+      present: start !== -1 || end !== -1,
+      complete: false,
+      checked: 0,
+      total: 0,
+      items: [],
+    };
+  }
+  const section = body.slice(start + REVIEW_READINESS_START.length, end);
+  const boxes = [...section.matchAll(/^\s*[-*]\s+\[([ xX])\]\s+/gm)];
+  const total = boxes.length;
+  const items = boxes.map((match) => ({ checked: match[1] !== " " }));
+  const checked = items.filter((item) => item.checked).length;
+  return {
+    present: true,
+    complete:
+      total === REVIEW_READINESS_ITEMS.length && checked === total,
+    checked,
+    total,
+    items,
+  };
+}
+
+/**
+ * Append the checklist section to a PR body. Idempotent: a body that already
+ * carries the marker pair is returned unchanged, so a re-run can never stack a
+ * second checklist (or feed the `edited` event endless body churn).
+ */
+function appendReviewReadinessSection(body) {
+  if (extractReviewReadiness(body).present) return body;
+  const section = buildReviewReadinessSection();
+  if (typeof body !== "string" || !body.trim()) return `${section}\n`;
+  return `${body.trimEnd()}\n\n${section}\n`;
+}
+
+/**
+ * Remove the bot-managed readiness section from a body. Used so the bot's own
+ * checklist never counts as author-written description substance, and so a
+ * confirmed maintainer's body can retire the injected section.
+ */
+function stripReviewReadinessSection(body) {
+  if (typeof body !== "string") return body;
+  const start = body.indexOf(REVIEW_READINESS_START);
+  const end = body.indexOf(REVIEW_READINESS_END);
+  if (start === -1 || end === -1 || end <= start) return body;
+  const stripped =
+    body.slice(0, start) + body.slice(end + REVIEW_READINESS_END.length);
+  return stripped.replace(/\n{3,}/g, "\n\n").trimEnd();
+}
+
 function collectPrQualityFailures({
   baseRef,
   allowedBases,
@@ -248,11 +360,18 @@ function collectPrQualityFailures({
 module.exports = {
   ANCESTRY_BEHIND_THRESHOLD,
   ANCESTRY_AHEAD_MAIN_MAX,
+  REVIEW_READINESS_ITEMS,
+  REVIEW_READINESS_START,
+  REVIEW_READINESS_END,
   isWrongAncestry,
   authorHasPushPermission,
   assessPrDescription,
   hasGuiCue,
   hasScreenshotEvidence,
+  buildReviewReadinessSection,
+  extractReviewReadiness,
+  appendReviewReadinessSection,
+  stripReviewReadinessSection,
   collectPrQualityFailures,
   hasEscapedNewlines,
   stripPrTemplateBoilerplate,