fix: bound model streaming

src/main/agent/bounded-response.test.ts

@@ -0,0 +1,48 @@
+import { describe, expect, it } from 'vitest'
+import { readBoundedResponseText } from './bounded-response'
+
+describe('readBoundedResponseText', () => {
+  it('cancels an oversized response as soon as it crosses the byte limit', async () => {
+    const chunk = new Uint8Array(1024 * 1024)
+    let pulls = 0
+    const response = new Response(
+      new ReadableStream<Uint8Array>({
+        pull(controller) {
+          pulls += 1
+          controller.enqueue(chunk)
+        }
+      })
+    )
+
+    await expect(
+      readBoundedResponseText(response, {
+        maxBytes: 8 * 1024 * 1024,
+        tooLargeMessage: 'response too large'
+      })
+    ).rejects.toThrow('response too large')
+    expect(pulls).toBeLessThan(20)
+  })
+
+  it('rejects an invalid declared response length without reading the body', async () => {
+    let pulls = 0
+    const response = new Response(
+      new ReadableStream<Uint8Array>({
+        pull(controller) {
+          pulls += 1
+          controller.enqueue(new Uint8Array([1]))
+        }
+      }),
+      {
+        headers: { 'content-length': 'invalid' }
+      }
+    )
+
+    await expect(
+      readBoundedResponseText(response, {
+        maxBytes: 1024,
+        tooLargeMessage: 'response too large'
+      })
+    ).rejects.toThrow('response too large')
+    expect(pulls).toBe(0)
+  })
+})