From 0cc84eca3f1575d1c5213425be8092a77d01ba3d Mon Sep 17 00:00:00 2001
From: mldangelo-oai <269034524+mldangelo-oai@users.noreply.github.com>
Date: Tue, 18 Aug 2026 10:26:36 -0700
Subject: [PATCH] fix: preserve exact multiscan lock identities

---
 sdk/typescript/src/multiscan.ts           |  4 ++--
 sdk/typescript/tests-ts/multiscan.test.ts | 28 ++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/sdk/typescript/src/multiscan.ts b/sdk/typescript/src/multiscan.ts
index 63f3a7909..d5d8f6e51 100644
--- a/sdk/typescript/src/multiscan.ts
+++ b/sdk/typescript/src/multiscan.ts
@@ -419,7 +419,7 @@ async function acquireLock(output: string): Promise<() => Promise<void>> {
       await rm(stale, { recursive: true, force: true });
     }
   }
-  const createdLock = await lstat(path);
+  const createdLock = await lstat(path, { bigint: true });
   const owner = `${JSON.stringify({
     pid: process.pid,
     ownerId: randomUUID(),
@@ -429,7 +429,7 @@ async function acquireLock(output: string): Promise<() => Promise<void>> {
   try {
     await writeFile(ownerPath, owner, { flag: "wx", mode: 0o600 });
   } catch (error) {
-    const currentLock = await lstat(path).catch(
+    const currentLock = await lstat(path, { bigint: true }).catch(
       (cleanup: NodeJS.ErrnoException) => {
         if (cleanup.code !== "ENOENT") throw cleanup;
         return undefined;
diff --git a/sdk/typescript/tests-ts/multiscan.test.ts b/sdk/typescript/tests-ts/multiscan.test.ts
index 2c62c0422..9f229fe04 100644
--- a/sdk/typescript/tests-ts/multiscan.test.ts
+++ b/sdk/typescript/tests-ts/multiscan.test.ts
@@ -1388,8 +1388,16 @@ describe("multiscan", () => {
   });
 
   test.each([false, true])(
-    "never removes a replacement lock when owner creation fails (owner published: %s)",
+    "never removes a replacement lock when owner creation fails (owner published: %p)",
     async (ownerPublished) => {
+      if (
+        runTestInSubprocess(
+          import.meta.path,
+          `never removes a replacement lock when owner creation fails (owner published: ${ownerPublished})`,
+        )
+      ) {
+        return;
+      }
       const paths = await fixture();
       const source = await repository(paths.root, "owner-creation-race");
       await writeFile(
@@ -1404,7 +1412,23 @@ describe("multiscan", () => {
         hostname: hostname(),
         processStartedAt: performance.timeOrigin,
       });
+      const createdInode = 2n ** 60n;
+      const replacementInode = createdInode + 1n;
+      expect(Number(createdInode)).toBe(Number(replacementInode));
+      let replaced = false;
+      const originalLstat = filesystem.lstat;
       const originalWriteFile = filesystem.writeFile;
+      const readLock = spyOn(filesystem, "lstat").mockImplementation((async (
+        ...args: Parameters<typeof filesystem.lstat>
+      ) => {
+        const metadata = await originalLstat(...args);
+        if (String(args[0]) === lock) {
+          const inode = replaced ? replacementInode : createdInode;
+          metadata.ino =
+            typeof metadata.ino === "bigint" ? inode : Number(inode);
+        }
+        return metadata;
+      }) as typeof filesystem.lstat);
       const writeOwner = spyOn(filesystem, "writeFile").mockImplementation(
         async (path, data, options) => {
           if (String(path) !== ownerPath) {
@@ -1413,6 +1437,7 @@ describe("multiscan", () => {
           writeOwner.mockRestore();
           await rename(lock, join(paths.output, ".lock.stale-owner-creation"));
           await mkdir(lock, { mode: 0o700 });
+          replaced = true;
           if (ownerPublished) {
             await originalWriteFile(ownerPath, replacement, { mode: 0o600 });
           }
@@ -1439,6 +1464,7 @@ describe("multiscan", () => {
         }
       } finally {
         writeOwner.mockRestore();
+        readLock.mockRestore();
       }
     },
   );