From 5fa348f3ed6254591d677e868382ba25ef3b0dcb Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Wed, 15 Jul 2026 00:53:47 +0100
Subject: [PATCH] fix(release): pin max-lines debt to branch merge base

---
 scripts/check-max-lines-ratchet.mjs          | 38 ++++++++-----
 test/scripts/check-max-lines-ratchet.test.ts | 57 ++++++++++++++++++++
 2 files changed, 82 insertions(+), 13 deletions(-)

diff --git a/scripts/check-max-lines-ratchet.mjs b/scripts/check-max-lines-ratchet.mjs
index 4765d7231c61..9cccf5bd20c6 100644
--- a/scripts/check-max-lines-ratchet.mjs
+++ b/scripts/check-max-lines-ratchet.mjs
@@ -276,19 +276,31 @@ function readBaselineAtRef(root, ref) {
 
 function resolveDefaultBase(root, staged) {
   const candidates = staged ? ["HEAD"] : ["origin/main", "HEAD"];
-  return (
-    candidates.find((ref) => {
-      try {
-        execFileSync("git", ["rev-parse", "--verify", ref + "^{commit}"], {
-          cwd: root,
-          stdio: "ignore",
-        });
-        return true;
-      } catch {
-        return false;
-      }
-    }) ?? null
-  );
+  const resolved = candidates.find((ref) => {
+    try {
+      execFileSync("git", ["rev-parse", "--verify", ref + "^{commit}"], {
+        cwd: root,
+        stdio: "ignore",
+      });
+      return true;
+    } catch {
+      return false;
+    }
+  });
+  if (!resolved || staged || resolved !== "origin/main") {
+    return resolved ?? null;
+  }
+  // A release or long-lived branch owns the suppression debt from its fork.
+  // Comparing against moving main would turn unrelated debt cleanup into a blocker.
+  try {
+    return execFileSync("git", ["merge-base", "HEAD", resolved], {
+      cwd: root,
+      encoding: "utf8",
+      stdio: ["ignore", "pipe", "ignore"],
+    }).trim();
+  } catch {
+    return resolved;
+  }
 }
 
 function writeBaseline(root, entries) {
diff --git a/test/scripts/check-max-lines-ratchet.test.ts b/test/scripts/check-max-lines-ratchet.test.ts
index 9b9ff7f2a19d..835dfcd2bbec 100644
--- a/test/scripts/check-max-lines-ratchet.test.ts
+++ b/test/scripts/check-max-lines-ratchet.test.ts
@@ -233,6 +233,63 @@ describe("check-max-lines-ratchet", () => {
     expect(main(root)).toBe(1);
   });
 
+  it("compares divergent worktrees against their main merge base", () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "openclaw-max-lines-diverged-"));
+    tempDirs.push(root);
+    fs.mkdirSync(path.join(root, "config"), { recursive: true });
+    fs.mkdirSync(path.join(root, "src"), { recursive: true });
+    fs.writeFileSync(path.join(root, "config/max-lines-baseline.txt"), "src/a.ts\nsrc/b.ts\n");
+    fs.writeFileSync(path.join(root, "src/a.ts"), "/* oxlint-disable max-lines */\n");
+    fs.writeFileSync(path.join(root, "src/b.ts"), "/* oxlint-disable max-lines */\n");
+    for (const args of [
+      ["init"],
+      ["config", "user.email", "test@example.com"],
+      ["config", "user.name", "Test"],
+      ["add", "."],
+      ["commit", "-m", "base"],
+      ["branch", "release"],
+    ]) {
+      git(root, args);
+    }
+
+    fs.writeFileSync(path.join(root, "config/max-lines-baseline.txt"), "src/a.ts\n");
+    fs.writeFileSync(path.join(root, "src/b.ts"), "export const b = 1;\n");
+    git(root, ["add", "."]);
+    git(root, ["commit", "-m", "shrink main debt"]);
+    git(root, ["update-ref", "refs/remotes/origin/main", "HEAD"]);
+    git(root, ["checkout", "release"]);
+
+    expect(main(root)).toBe(0);
+  });
+
+  it("falls back to main when no merge base is available", () => {
+    const root = fs.mkdtempSync(path.join(os.tmpdir(), "openclaw-max-lines-disconnected-"));
+    tempDirs.push(root);
+    fs.mkdirSync(path.join(root, "config"), { recursive: true });
+    fs.mkdirSync(path.join(root, "src"), { recursive: true });
+    fs.writeFileSync(path.join(root, "config/max-lines-baseline.txt"), "src/a.ts\n");
+    fs.writeFileSync(path.join(root, "src/a.ts"), "/* oxlint-disable max-lines */\n");
+    for (const args of [
+      ["init"],
+      ["config", "user.email", "test@example.com"],
+      ["config", "user.name", "Test"],
+      ["add", "."],
+      ["commit", "-m", "release"],
+      ["branch", "-m", "release"],
+    ]) {
+      git(root, args);
+    }
+    git(root, ["checkout", "--orphan", "main"]);
+    fs.writeFileSync(path.join(root, "config/max-lines-baseline.txt"), "");
+    fs.writeFileSync(path.join(root, "src/a.ts"), "export const a = 1;\n");
+    git(root, ["add", "."]);
+    git(root, ["commit", "-m", "disconnected main"]);
+    git(root, ["update-ref", "refs/remotes/origin/main", "HEAD"]);
+    git(root, ["checkout", "release"]);
+
+    expect(main(root)).toBe(1);
+  });
+
   it("checks staged content instead of unstaged worktree edits", () => {
     const root = fs.mkdtempSync(path.join(os.tmpdir(), "openclaw-max-lines-staged-"));
     tempDirs.push(root);