fix(useFetch): broken callbacks when RequestInit and UseFetchOptions are both passed in

packages/core/useFetch/index.test.ts

@@ -181,6 +181,81 @@ describe('useFetch', () => {
     })
   })
 
+  test('should chain beforeFetch function when using a factory instance and the options object in useMyFetch', async () => {
+    const useMyFetch = createFetch({
+      baseUrl: 'https://example.com',
+      options: {
+        beforeFetch({ options }) {
+          options.headers = { ...options.headers, Global: 'foo' }
+          return { options }
+        },
+      },
+    })
+    useMyFetch(
+      'test',
+      { method: 'GET' },
+      {
+        beforeFetch({ options }) {
+          options.headers = { ...options.headers, Local: 'foo' }
+          return { options }
+        },
+      })
+
+    await retry(() => {
+      expect(fetchSpyHeaders()).toMatchObject({ Global: 'foo', Local: 'foo' })
+    })
+  })
+
+  test('should chain afterFetch function when using a factory instance and the options object in useMyFetch', async () => {
+    const useMyFetch = createFetch({
+      baseUrl: 'https://example.com',
+      options: {
+        afterFetch(ctx) {
+          ctx.data.title = 'Global'
+          return ctx
+        },
+      },
+    })
+    const { data } = useMyFetch(
+      'test?json',
+      { method: 'GET' },
+      {
+        afterFetch(ctx) {
+          ctx.data.title += ' Local'
+          return ctx
+        },
+      }).json()
+
+    await retry(() => {
+      expect(data.value).toEqual(expect.objectContaining({ title: 'Global Local' }))
+    })
+  })
+
+  test('should chain onFetchError function when using a factory instance and the options object in useMyFetch', async () => {
+    const useMyFetch = createFetch({
+      baseUrl: 'https://example.com',
+      options: {
+        onFetchError(ctx) {
+          ctx.data.title = 'Global'
+          return ctx
+        },
+      },
+    })
+    const { data } = useMyFetch(
+      'test?status=400&json',
+      { method: 'GET' },
+      {
+        onFetchError(ctx) {
+          ctx.data.title += ' Local'
+          return ctx
+        },
+      }).json()
+
+    await retry(() => {
+      expect(data.value).toEqual(expect.objectContaining({ title: 'Global Local' }))
+    })
+  })
+
   test('should run the beforeFetch function and add headers to the request', async () => {
     useFetch('https://example.com', { headers: { 'Accept-Language': 'en-US' } }, {
       beforeFetch({ options }) {

packages/core/useFetch/index.ts

@@ -260,8 +260,15 @@ export function createFetch(config: CreateFetchOptions = {}) {
       }
     }
 
-    if (args.length > 1 && isFetchOptions(args[1]))
-      options = { ...options, ...args[1] }
+    if (args.length > 1 && isFetchOptions(args[1])) {
+      options = {
+        ...options,
+        ...args[1],
+        beforeFetch: chainCallbacks(_options.beforeFetch, args[1].beforeFetch),
+        afterFetch: chainCallbacks(_options.afterFetch, args[1].afterFetch),
+        onFetchError: chainCallbacks(_options.onFetchError, args[1].onFetchError),
+      }
+    }
 
     return useFetch(computedUrl, fetchOptions, options)
   }