From aafe79c44587b17686279be15a934879a91c28e9 Mon Sep 17 00:00:00 2001
From: Abhinav Kumar Singh <abhinav.kr.singh.2610@gmail.com>
Date: Sat, 15 Aug 2026 14:34:07 +0530
Subject: [PATCH] fix: preserve ArrayBufferView bounds

---
 src/core.ts         |  3 ++-
 tests/index.test.ts | 24 ++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/src/core.ts b/src/core.ts
index 10b9d3f..fe07747 100644
--- a/src/core.ts
+++ b/src/core.ts
@@ -273,7 +273,8 @@ export abstract class APIClient {
           opts && isBlobLike(opts?.body) ? new DataView(await opts.body.arrayBuffer())
           : opts?.body instanceof DataView ? opts.body
           : opts?.body instanceof ArrayBuffer ? new DataView(opts.body)
-          : opts && ArrayBuffer.isView(opts?.body) ? new DataView(opts.body.buffer)
+          : opts && ArrayBuffer.isView(opts?.body) ?
+            new DataView(opts.body.buffer, opts.body.byteOffset, opts.body.byteLength)
           : opts?.body;
         return { method, path, ...opts, body };
       }),
diff --git a/tests/index.test.ts b/tests/index.test.ts
index 7639b23..c8282bf 100644
--- a/tests/index.test.ts
+++ b/tests/index.test.ts
@@ -236,6 +236,30 @@ describe('instantiate client', () => {
 describe('request building', () => {
   const client = new Browserbase({ apiKey: 'My API Key' });
 
+  describe('binary bodies', () => {
+    test.each([
+      ['Uint8Array', new Uint8Array([10, 20, 30, 40]), [10, 20, 30, 40]],
+      ['Uint8Array subarray', new Uint8Array([10, 20, 30, 40]).subarray(1, 3), [20, 30]],
+      ['Buffer subarray', Buffer.from([10, 20, 30, 40]).subarray(1, 3), [20, 30]],
+    ])('preserves the bounds of a %s', async (_name, input, expected) => {
+      let capturedBody: unknown;
+      const binaryClient = new Browserbase({
+        apiKey: 'My API Key',
+        maxRetries: 0,
+        fetch: async (_url, init) => {
+          capturedBody = init?.body;
+          return new Response(JSON.stringify({}), { headers: { 'Content-Type': 'application/json' } });
+        },
+      });
+
+      await binaryClient.post('/foo', { body: input, __binaryRequest: true });
+
+      expect(capturedBody).toBeInstanceOf(DataView);
+      const view = capturedBody as DataView;
+      expect(Array.from(new Uint8Array(view.buffer, view.byteOffset, view.byteLength))).toEqual(expected);
+    });
+  });
+
   describe('Content-Length', () => {
     test('handles multi-byte characters', async () => {
       const { req } = await client.buildRequest({ path: '/foo', method: 'post', body: { value: '—' } });