test: cover probeImage error wrapping and the retreating durable boundary

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

@@ -1,6 +1,6 @@
 import sharp from 'sharp'
 import { describe, expect, it } from 'vitest'
-import { detectImage } from '../src/image.ts'
+import { detectImage, probeImage } from '../src/image.ts'
 
 async function raster(format: 'png' | 'jpeg' | 'webp' | 'gif'): Promise<Uint8Array> {
   const image = sharp({
@@ -39,4 +39,13 @@ describe('raster decoding', () => {
     await expect(sharp(truncated).metadata()).resolves.toMatchObject({ width: 3, height: 2 })
     await expect(detectImage(truncated)).rejects.toMatchObject({ code: 'INVALID_IMAGE' })
   })
+
+  it('probes malformed bytes and unsupported formats into the same stable error', async () => {
+    await expect(probeImage(Uint8Array.of(1, 2, 3)))
+      .rejects.toMatchObject({ code: 'INVALID_IMAGE' })
+    const unsupported = await sharp({
+      create: { width: 1, height: 1, channels: 4, background: { r: 0, g: 0, b: 0, alpha: 1 } },
+    }).tiff().toBuffer()
+    await expect(probeImage(unsupported)).rejects.toMatchObject({ code: 'INVALID_IMAGE' })
+  })
 })

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

@@ -77,6 +77,14 @@ describe('local attachment store', () => {
     ])
   })
 
+  it('retreats the durable boundary to the closest existing ancestor when the home directory does not exist yet', async () => {
+    const storageRoot = join(await root(), 'home', 'attachments', 'v1')
+
+    const ref = await saveImageFile(storageRoot, { data: PNG, mediaType: 'image/png' }, LIMITS)
+
+    await expect(readImageFile(storageRoot, ref)).resolves.toEqual({ ref, data: PNG })
+  })
+
   it('publishes one private content-addressed object and deduplicates equal bytes', async () => {
     const storageRoot = await root()
     const first = await saveImageFile(storageRoot, {