fix: replace MultipartFile with File | Blob in client body types

Author: Julien-R44

.changeset/fix-multipart-file-types.md

@@ -0,0 +1,7 @@
+---
+'@tuyau/core': patch
+---
+
+Replace `MultipartFile` with `File | Blob` in client-side body types.
+
+When using `vine.file()` in validators, the generated types previously exposed `MultipartFile` (a server-side type) to the client, forcing users to cast it to `File` or `Blob` when handling file uploads on the client. With this change,`ExtractBody` now automatically replaces `MultipartFile` with `File | Blob`.

packages/core/src/client/types/types.ts

@@ -75,11 +75,27 @@ export type ExtractQuery<T> = 'query' extends keyof T
  */
 export type ExtractQueryForGet<T> = DistributiveOmit<T, 'headers' | 'cookies' | 'params'>
 
+/**
+ * Recursively replaces AdonisJS MultipartFile types with the DOM File type.
+ * MultipartFile is matched structurally via `{ isMultipartFile: true }` to avoid
+ * importing from @adonisjs/bodyparser in client-side code.
+ */
+type ReplaceMultipartFile<T> = T extends { isMultipartFile: true }
+  ? File | Blob
+  : T extends (infer U)[]
+    ? ReplaceMultipartFile<U>[]
+    : T extends object
+      ? { [K in keyof T]: ReplaceMultipartFile<T[K]> }
+      : T
+
 /**
  * Extract body from a validator type, excluding reserved properties.
  * Excludes 'query', 'params', 'headers', and 'cookies' as these are handled separately by AdonisJS.
+ * Also replaces MultipartFile types with DOM File for client-side usage.
  */
-export type ExtractBody<T> = DistributiveOmit<T, 'query' | 'params' | 'headers' | 'cookies'>
+export type ExtractBody<T> = ReplaceMultipartFile<
+  DistributiveOmit<T, 'query' | 'params' | 'headers' | 'cookies'>
+>
 
 /**
  * Success status codes (2xx)

packages/core/tests/typings.spec.ts

@@ -924,6 +924,34 @@ test.group('ExtractQuery and ExtractBody types', (group) => {
       password: string
     }>()
   })
+
+  test('ExtractBody replaces MultipartFile with File | Blob', ({ expectTypeOf }) => {
+    type WithFile = { avatar: { isMultipartFile: true; fieldName: string; size: number }; name: string }
+
+    type Result = ExtractBody<WithFile>
+    expectTypeOf<Result>().toEqualTypeOf<{ avatar: File | Blob; name: string }>()
+  })
+
+  test('ExtractBody replaces MultipartFile array with (File | Blob) array', ({ expectTypeOf }) => {
+    type WithFiles = { documents: { isMultipartFile: true; fieldName: string }[]; title: string }
+
+    type Result = ExtractBody<WithFiles>
+    expectTypeOf<Result>().toEqualTypeOf<{ documents: (File | Blob)[]; title: string }>()
+  })
+
+  test('ExtractBody replaces optional MultipartFile with optional File | Blob', ({ expectTypeOf }) => {
+    type WithOptionalFile = { avatar?: { isMultipartFile: true; fieldName: string }; name: string }
+
+    type Result = ExtractBody<WithOptionalFile>
+    expectTypeOf<Result>().toEqualTypeOf<{ avatar?: File | Blob; name: string }>()
+  })
+
+  test('ExtractBody does not affect non-file types', ({ expectTypeOf }) => {
+    type NoFiles = { name: string; age: number; active: boolean }
+
+    type Result = ExtractBody<NoFiles>
+    expectTypeOf<Result>().toEqualTypeOf<{ name: string; age: number; active: boolean }>()
+  })
 })
 
 test.group('ExtractResponse type', (group) => {