feat(ci): verify checklist claims and reset readiness on head drift

.github/scripts/pr-maintainers.cjs

@@ -0,0 +1,35 @@
+"use strict";
+
+/**
+ * Maintainers from `MAINTAINERS.md` text. Only the current-maintainers table
+ * is authoritative; the change log below it can mention retired accounts.
+ * Missing the section heading means we cannot identify current maintainers,
+ * so the recipient list is empty rather than scanning the whole file.
+ */
+function parseMaintainerLogins(text) {
+  const heading = /^## Current maintainers[ \t]*\r?$/m.exec(text ?? "");
+  if (heading === null) {
+    return [];
+  }
+
+  const sectionStart = heading.index;
+  const nextHeading = text.indexOf(
+    "\n## ",
+    sectionStart + "## Current maintainers".length
+  );
+  const section = text.slice(
+    sectionStart,
+    nextHeading === -1 ? text.length : nextHeading
+  );
+  const logins = [
+    ...section.matchAll(
+      /\[\@([A-Za-z0-9_-]+)\]\(https:\/\/github\.com\/[^)]*\)/g
+    )
+  ].map(match => match[1]);
+
+  return [...new Set(logins)];
+}
+
+module.exports = {
+  parseMaintainerLogins
+};

.github/scripts/pr-maintainers.test.cjs

@@ -0,0 +1,75 @@
+"use strict";
+
+const { describe, it } = require("node:test");
+const assert = require("node:assert/strict");
+const {
+  parseMaintainerLogins
+} = require("./pr-maintainers.cjs");
+
+const FIXTURE = [
+  "## Current maintainers",
+  "",
+  "| GitHub account | Project role | Responsibilities |",
+  "| --- | --- | --- |",
+  "| [@lidge-jun](https://github.com/lidge-jun) | Project owner | x |",
+  "| [@Ingwannu](https://github.com/Ingwannu) | Maintainer | x |",
+  "| [@Wibias](https://github.com/Wibias) | Maintainer | x |",
+  "",
+  "## Change log",
+  "",
+  "- [@Wibias](https://github.com/Wibias) was added as a maintainer.",
+  "- [@retired](https://github.com/retired) stepped down.",
+].join("\n");
+
+describe("parseMaintainerLogins", () => {
+  it("reads the current-maintainers table and excludes the change log", () => {
+    assert.deepEqual(parseMaintainerLogins(FIXTURE), [
+      "lidge-jun",
+      "Ingwannu",
+      "Wibias",
+    ]);
+  });
+
+  it("returns an empty list when the section heading is missing", () => {
+    const text = "- [@only](https://github.com/only) is listed.";
+    assert.deepEqual(parseMaintainerLogins(text), []);
+  });
+  it("does not match a ### subsection or prose mentioning the heading", () => {
+    const subsection = [
+      "### Current maintainers",
+      "| [@subsection](https://github.com/subsection) | x |",
+    ].join("\n");
+    assert.deepEqual(parseMaintainerLogins(subsection), []);
+
+    const prose = [
+      "See the ## Current maintainers section below.",
+      "| [@prose](https://github.com/prose) | x |",
+    ].join("\n");
+    assert.deepEqual(parseMaintainerLogins(prose), []);
+  });
+
+  it("accepts a valid CRLF heading with trailing whitespace and a following H2", () => {
+    const crlf = [
+      "## Current maintainers \t",
+      "| [@crlf](https://github.com/crlf) | x |",
+      "## Changelog",
+      "| [@retired](https://github.com/retired) | y |",
+    ].join("\r\n");
+    assert.deepEqual(parseMaintainerLogins(crlf), ["crlf"]);
+  });
+
+
+  it("handles empty and duplicate-free output", () => {
+    assert.deepEqual(parseMaintainerLogins(""), []);
+    assert.deepEqual(
+      parseMaintainerLogins(
+        [
+          "## Current maintainers",
+          "| [@dup](https://github.com/dup) | x |",
+          "| [@dup](https://github.com/dup) | y |",
+        ].join("\n"),
+      ),
+      ["dup"],
+    );
+  });
+});

.github/scripts/pr-quality-messages.cjs

@@ -0,0 +1,185 @@
+"use strict";
+
+const {
+  REVIEW_READINESS_ITEMS
+} = require("./pr-quality.cjs");
+const {
+  readinessStateMarker
+} = require("./pr-quality-state.cjs");
+
+/** Marks the bot's review-readiness checklist message. */
+const READINESS_MARKER = "<!-- pr-quality-readiness -->";
+
+function inlineCode(value) {
+  const text = String(value);
+  const longestBacktickRun = Math.max(
+    0,
+    ...(text.match(/`+/g) ?? []).map(run => run.length)
+  );
+  const delimiter = "`".repeat(longestBacktickRun + 1);
+  return `${delimiter}${text}${delimiter}`;
+}
+
+function readinessChecklistLines(readiness) {
+  return REVIEW_READINESS_ITEMS.map(
+    (item, index) =>
+      `- ${readiness.items?.[index]?.checked ? "✅" : "⬜"} ${item}`
+  );
+}
+
+/**
+ * The full readiness-message body: marker, serialized state, mirror lines for
+ * the tickable boxes, the tick count, and the path-specific extra lines.
+ */
+function buildReadinessCommentBody(state, readiness, extra) {
+  const complete = readiness.present && readiness.complete;
+
+  return [
+    READINESS_MARKER,
+    readinessStateMarker(state),
+    "",
+    "## Review readiness checklist",
+    "",
+    readiness.present
+      ? "This PR is kept in **draft** until every requirement below is fulfilled. The tickable checklist has been added to your PR description — tick all four boxes there."
+      : "The review readiness checklist is not required for this author.",
+    "",
+    ...(readiness.present ? readinessChecklistLines(readiness) : []),
+    "",
+    readiness.present
+      ? complete
+        ? "✅ **4/4** boxes ticked."
+        : `**${readiness.checked}/${readiness.total}** boxes ticked.`
+      : "",
+    "",
+    ...extra
+  ];
+}
+
+function descriptionFailureLines(reason) {
+  switch (reason) {
+    case "empty":
+      return [
+        "The pull request body is empty after stripping HTML comments.",
+        "",
+        "Include a real description: a **Summary** of what changed and why, plus a **Test plan** (or equivalent substance)."
+      ];
+    case "placeholder":
+      return [
+        "The pull request body contains only placeholder text (for example `N/A`, `TODO`, or `No response`).",
+        "",
+        "Replace placeholders with a **Summary** and **Test plan**, or another description with at least two substantive sections or paragraphs."
+      ];
+    case "escaped_newlines":
+      return [
+        "The pull request body uses literal `\\n` escape sequences instead of real line breaks.",
+        "",
+        "Fix the formatting so the body uses normal markdown line breaks, then add a **Summary** and **Test plan**."
+      ];
+    case "thin":
+    default:
+      return [
+        "The pull request description is too thin to review.",
+        "",
+        "Add a **Summary** and **Test plan** (two sections with at least 40 characters each), or an unstructured body of at least 120 characters with two paragraphs or bullet groups."
+      ];
+  }
+}
+
+function buildFailureSections(failures, { pr, allowedBases, defaultBase }) {
+  const sections = [];
+
+  if (failures.some(failure => failure.code === "wrong_base")) {
+    sections.push(
+      "⚠️ **Wrong target branch**",
+      "",
+      `This pull request currently targets ${inlineCode(pr.base.ref)}, but pull requests must target one of ${allowedBases.map(inlineCode).join(" or ")}.`,
+      "",
+      `@${pr.user.login} Please retarget this PR to ${inlineCode(defaultBase)}. All contributions go to ${inlineCode(defaultBase)}; \`main\` receives only release promotions. See our [Contributing guide](https://lidge-jun.github.io/opencodex/contributing/) for details. Thanks! 🙏`
+    );
+  }
+
+  if (failures.some(failure => failure.code === "wrong_ancestry")) {
+    sections.push(
+      "⚠️ **Wrong branch ancestry**",
+      "",
+      `This pull request targets ${inlineCode(pr.base.ref)}, but its head appears to sit on the current ${inlineCode("main")} tip while being far behind ${inlineCode(pr.base.ref)}.`,
+      "",
+      `@${pr.user.login} Rebase onto the current ${inlineCode(pr.base.ref)} branch instead of opening from ${inlineCode("main")}. That keeps already-released commits out of the integration branch.`
+    );
+  }
+
+  const badDescription = failures.find(
+    failure => failure.code === "bad_description"
+  );
+  if (badDescription) {
+    sections.push(
+      "⚠️ **Pull request description**",
+      "",
+      ...descriptionFailureLines(badDescription.reason)
+    );
+  }
+
+  if (
+    failures.some(
+      failure => failure.code === "missing_ui_screenshot"
+    )
+  ) {
+    sections.push(
+      "⚠️ **UI screenshot required**",
+      "",
+      `This pull request mentions ${inlineCode("gui")} in its title or description, so it is treated as a GUI change.`,
+      "",
+      `@${pr.user.login} Please add a screenshot of the UI change to the description — drag and drop the image into the description editor, or paste a markdown image such as ${inlineCode("![Screenshot](https://example.com/after.png)")}. The check re-runs automatically once the description is edited.`
+    );
+  }
+
+  return sections;
+}
+
+function failureSummary(failures, { pr }) {
+  return failures
+    .map(failure => {
+      if (failure.code === "wrong_base") {
+        return `wrong base (${pr.base.ref})`;
+      }
+      if (failure.code === "wrong_ancestry") {
+        return "wrong ancestry";
+      }
+      if (failure.code === "bad_description") {
+        return `bad description (${failure.reason})`;
+      }
+      if (failure.code === "missing_ui_screenshot") {
+        return "missing UI screenshot";
+      }
+      return failure.code;
+    })
+    .join("; ");
+}
+
+/** The reset notice shown when a completion no longer covers the live head. */
+function buildStaleNotice({ completionHeadSha, liveHeadSha, eventAction }) {
+  let lead;
+  if (completionHeadSha !== null) {
+    lead = `New commits were pushed after the checklist was completed on ${inlineCode(String(completionHeadSha).slice(0, 7))}; the current head is ${inlineCode(liveHeadSha.slice(0, 7))}.`;
+  } else if (eventAction === "synchronize") {
+    lead = `A complete checklist was found on a synchronize event with no recorded completion head; the current head is ${inlineCode(liveHeadSha.slice(0, 7))}.`;
+  } else {
+    lead = `The checklist was ticked before the current head ${inlineCode(liveHeadSha.slice(0, 7))} was pushed.`;
+  }
+  return [
+    lead,
+    "The checklist has been reset: re-test against the latest code and tick all four boxes again."
+  ];
+}
+
+module.exports = {
+  READINESS_MARKER,
+  inlineCode,
+  readinessChecklistLines,
+  buildReadinessCommentBody,
+  descriptionFailureLines,
+  buildFailureSections,
+  failureSummary,
+  buildStaleNotice
+};