feat: enable safe reopening of prs (#2429)

Signed-off-by: exploreriii <133720349+exploreriii@users.noreply.github.com>

Author: exploreriii

.github/scripts/__tests__/jest/bot-contributor-lifecycle.test.js

@@ -29,6 +29,7 @@ function makeEnv(spec) {
     failUnassignFor = [], // logins whose removeAssignees call should throw
     failCommentOn = [], // issue/PR numbers whose createComment call should throw
     failCloseFor = [], // PR numbers whose pulls.update (close) call should throw
+    reopenedAtByPr = {}, // PR number -> ISO date of its latest `reopened` event
   } = spec;
 
   const github = {
@@ -50,6 +51,8 @@ function makeEnv(spec) {
           }
           mut.unassigned.push({ issue_number, assignees });
         },
+        listEvents: ({ issue_number }) =>
+          reopenedAtByPr[issue_number] ? [{ event: "reopened", created_at: reopenedAtByPr[issue_number] }] : [],
       },
       pulls: {
         get: async ({ pull_number }) => {
@@ -610,6 +613,53 @@ describe("bot-contributor-lifecycle", () => {
     expect(m.unassigned).toHaveLength(0);
   });
 
+  test("a recently reopened stale PR is NOT re-closed — the clock restarts from the reopen", async () => {
+    // The maintainer-recovery flow: PR closed for staleness weeks ago, contributor is
+    // re-assigned and the PR reopened 2 days ago with no new commits yet. Must survive.
+    const spec = {
+      ...specWithPR(143, 271, "alice", { author: "alice", reviews: [humanReview(70)], commitDate: daysAgo(80) }),
+      reopenedAtByPr: { 271: daysAgo(2) },
+    };
+    const m = await run(spec, { DRY_RUN: "false" });
+    expect(m.closed).toHaveLength(0);
+    expect(m.comments).toHaveLength(0);
+    expect(m.unassigned).toHaveLength(0);
+  });
+
+  test("a reopen also prevents a premature reminder (remind-window case)", async () => {
+    // Last review is inside the remind window (15d) but the PR was manually closed
+    // and reopened 2 days ago — the reopen is the newest activity, so no action.
+    const spec = {
+      ...specWithPR(146, 274, "alice", { author: "alice", reviews: [humanReview(15)], commitDate: daysAgo(20) }),
+      reopenedAtByPr: { 274: daysAgo(2) },
+    };
+    const m = await run(spec, { DRY_RUN: "false" });
+    expect(m.closed).toHaveLength(0);
+    expect(m.comments).toHaveLength(0);
+    expect(m.unassigned).toHaveLength(0);
+  });
+
+  test("a reopened PR idle past the remind threshold gets a reminder, not a close", async () => {
+    const spec = {
+      ...specWithPR(144, 272, "alice", { author: "alice", reviews: [humanReview(70)], commitDate: daysAgo(80) }),
+      reopenedAtByPr: { 272: daysAgo(15) },
+    };
+    const m = await run(spec, { DRY_RUN: "false" });
+    expect(m.closed).toHaveLength(0);
+    expect(commentedOn(m, 272, "<!-- pr-inactivity-bot-marker -->")).toBe(true);
+    expect(m.unassigned).toHaveLength(0);
+  });
+
+  test("a reopened PR that idles past the close threshold again IS closed", async () => {
+    const spec = {
+      ...specWithPR(145, 273, "alice", { author: "alice", reviews: [humanReview(90)], commitDate: daysAgo(95) }),
+      reopenedAtByPr: { 273: daysAgo(70) },
+    };
+    const m = await run(spec, { DRY_RUN: "false" });
+    expect(m.closed.some((c) => c.pull_number === 273)).toBe(true);
+    expect(unassignedFrom(m, 145, "alice")).toBe(true);
+  });
+
   test("writes a markdown stats table to GITHUB_STEP_SUMMARY when set", async () => {
     const dir = fs.mkdtempSync(path.join(os.tmpdir(), "lifecycle-summary-"));
     const summaryFile = path.join(dir, "summary.md");

.github/scripts/bot-contributor-lifecycle.js

@@ -24,6 +24,10 @@ assignees (not PRs). For each issue it applies a staged escalation:
 "age" is measured from the most recent activity, which always includes a recent
 `/working` comment from an assignee — so `/working` resets every timer. PR age
 also includes the last commit and the last human (non-bot, non-author) review.
+Reopening a closed PR also counts as activity: the reopen timestamp restarts the
+clock, so a deliberately revived PR gets a full fresh remind/close cycle instead
+of being re-closed on the next run (works for PRs closed by the pre-consolidation
+bots too, whose close comments carried no marker).
 
 Markers are cycle-scoped: a bot marker comment only suppresses a repeat action if it
 was posted AFTER the current cycle began (the assignee's latest assignment for issue
@@ -283,6 +287,33 @@ async function lastCommitDate(github, pr) {
   }
 }
 
+// Most recent `reopened` event on the PR (Date or null). A reopen is a deliberate
+// human signal — server-timestamped and works no matter who/what closed the PR
+// (including the pre-consolidation bots, whose close comments carried no marker) —
+// so it resets the inactivity clock and grants a full fresh remind/close cycle.
+// Only called when a PR is old enough that the bot is about to act on it
+// (remind or close), so the extra API call stays rare.
+async function lastReopenedDate(github, owner, repo, prNumber) {
+  try {
+    const events = await github.paginate(github.rest.issues.listEvents, {
+      owner,
+      repo,
+      issue_number: prNumber,
+      per_page: 100,
+    });
+    let latest = null;
+    for (const e of events) {
+      if (e?.event !== "reopened" || !e.created_at) continue;
+      const d = new Date(e.created_at);
+      if (!latest || d > latest) latest = d;
+    }
+    return latest;
+  } catch (err) {
+    console.log(`  [WARN] Could not fetch events for PR #${prNumber}:`, err.message || err);
+    return null;
+  }
+}
+
 // ---- message builders ----
 
 function issueReminderBody(assignees) {
@@ -496,10 +527,25 @@ async function handlePRStage(github, owner, repo, issue, graph, prNumbers, comme
       continue;
     }
     const commitDate = await lastCommitDate(github, pr);
-    const activityAt = maxDate([reviewDate, commitDate, workingAt]);
-    const ageDays = daysSince(activityAt, nowMs);
+    let activityAt = maxDate([reviewDate, commitDate, workingAt]);
+    let ageDays = daysSince(activityAt, nowMs);
     console.log(`    [INFO] PR #${prNum} reviewed; last activity ~${ageDays}d ago`);
 
+    // Before reminding/closing, honour a deliberate reopen: if the PR was reopened
+    // after its last review/commit activity, the reopen timestamp becomes the
+    // activity baseline, so a revived PR gets a full new remind/close cycle instead
+    // of a premature reminder or an immediate re-close (a silent close/reopen war
+    // the human can't win). Checked whenever the bot is about to take ANY action.
+    const actionThreshold = Math.min(cfg.prRemindDays, cfg.prCloseDays);
+    if (ageDays >= actionThreshold) {
+      const reopenedAt = await lastReopenedDate(github, owner, repo, prNum);
+      if (reopenedAt && (!activityAt || reopenedAt > activityAt)) {
+        activityAt = maxDate([activityAt, reopenedAt]);
+        ageDays = daysSince(activityAt, nowMs);
+        console.log(`    [INFO] PR #${prNum} was reopened ~${ageDays}d ago; clock restarted from the reopen`);
+      }
+    }
+
     // Close takes priority over remind so an (unusual) close < remind config still closes.
     if (ageDays >= cfg.prCloseDays) {
       toClose.push({ prNum, ageDays, activityAt });