fix: preserve multi-image prompt batches

packages/attachment/attachment-local/tests/index.spec.ts

@@ -1,4 +1,5 @@
 import { Context } from 'cordis'
+import { existsSync } from 'node:fs'
 import { mkdtemp, rm } from 'node:fs/promises'
 import { tmpdir } from 'node:os'
 import { join } from 'node:path'
@@ -6,6 +7,8 @@ import { describe, expect, it } from 'vitest'
 import LocalAttachmentStore, {
   DEFAULT_MAX_IMAGE_BYTES,
   DEFAULT_MAX_IMAGE_PIXELS,
+  DEFAULT_MAX_IMAGES_PER_MESSAGE,
+  DEFAULT_MAX_MESSAGE_IMAGE_BYTES,
 } from '../src/index.ts'
 
 describe('local attachment service', () => {
@@ -13,6 +16,8 @@ describe('local attachment service', () => {
     const service = new LocalAttachmentStore(new Context(), {})
     expect(service.imageLimits).toEqual({
       maxImageBytes: DEFAULT_MAX_IMAGE_BYTES,
+      maxImagesPerMessage: DEFAULT_MAX_IMAGES_PER_MESSAGE,
+      maxMessageImageBytes: DEFAULT_MAX_MESSAGE_IMAGE_BYTES,
       maxImagePixels: DEFAULT_MAX_IMAGE_PIXELS,
       mediaTypes: ['image/png', 'image/jpeg', 'image/webp', 'image/gif'],
     })
@@ -32,4 +37,21 @@ describe('local attachment service', () => {
       await rm(dshHome, { recursive: true, force: true })
     }
   })
+
+  it('validates without persisting: a rejected image leaves no storage root behind', async () => {
+    const dshHome = await mkdtemp(join(tmpdir(), 'dsh-attachment-validate-'))
+    try {
+      const service = new LocalAttachmentStore(new Context(), { dshHome })
+      expect(() => { service.validateImage({ data: Uint8Array.of(1, 2, 3), mediaType: 'image/png' }) })
+        .toThrow(/Unsupported or malformed image data/)
+      const valid = Uint8Array.from(Buffer.from(
+        'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNk+A8AAQUBAScY42YAAAAASUVORK5CYII=',
+        'base64',
+      ))
+      expect(() => { service.validateImage({ data: valid, mediaType: 'image/png' }) }).not.toThrow()
+      expect(existsSync(service.root)).toBe(false)
+    } finally {
+      await rm(dshHome, { recursive: true, force: true })
+    }
+  })
 })