From 70ff80c17541ca445610e020a6f9b402e0c648d9 Mon Sep 17 00:00:00 2001
From: Dennis Nikolay <dennisnikolay@posteo.de>
Date: Thu, 19 Dec 2024 12:41:31 +0100
Subject: [PATCH] [2.x] Fix useForm re-renders by memoizing functions in React
 (same changes as inertiajs#1607 for v2)

---
 packages/react/src/useForm.ts | 110 +++++++++++++++++++++-------------
 1 file changed, 69 insertions(+), 41 deletions(-)

diff --git a/packages/react/src/useForm.ts b/packages/react/src/useForm.ts
index cdf449744..15ce6af64 100644
--- a/packages/react/src/useForm.ts
+++ b/packages/react/src/useForm.ts
@@ -59,7 +59,7 @@ export default function useForm<TForm extends FormDataType>(
   const [progress, setProgress] = useState(null)
   const [wasSuccessful, setWasSuccessful] = useState(false)
   const [recentlySuccessful, setRecentlySuccessful] = useState(false)
-  let transform = (data) => data
+  const transform = useRef((data) => data)
 
   useEffect(() => {
     isMounted.current = true
@@ -158,17 +158,16 @@ export default function useForm<TForm extends FormDataType>(
       }
 
       if (method === 'delete') {
-        router.delete(url, { ..._options, data: transform(data) })
+        router.delete(url, { ..._options, data: transform.current(data) })
       } else {
-        router[method](url, transform(data), _options)
+        router[method](url, transform.current(data), _options)
       }
     },
     [data, setErrors, transform],
   )
 
-  return {
-    data,
-    setData(keyOrData: keyof TForm | Function | TForm, maybeValue?: TForm[keyof TForm]) {
+  const setDataFunction = useCallback(
+    (keyOrData: keyof TForm | Function | TForm, maybeValue?: TForm[keyof TForm]) => {
       if (typeof keyOrData === 'string') {
         setData((data) => ({ ...data, [keyOrData]: maybeValue }))
       } else if (typeof keyOrData === 'function') {
@@ -177,17 +176,11 @@ export default function useForm<TForm extends FormDataType>(
         setData(keyOrData as TForm)
       }
     },
-    isDirty: !isEqual(data, defaults),
-    errors,
-    hasErrors,
-    processing,
-    progress,
-    wasSuccessful,
-    recentlySuccessful,
-    transform(callback) {
-      transform = callback
-    },
-    setDefaults(fieldOrFields?: keyof TForm | Partial<TForm>, maybeValue?: FormDataConvertible) {
+    [setData],
+  )
+
+  const setDefaultsFunction = useCallback(
+    (fieldOrFields?: keyof TForm | Partial<TForm>, maybeValue?: FormDataConvertible) => {
       if (typeof fieldOrFields === 'undefined') {
         setDefaults(() => data)
       } else {
@@ -197,11 +190,15 @@ export default function useForm<TForm extends FormDataType>(
         }))
       }
     },
-    reset(...fields) {
+    [data, setDefaults],
+  )
+
+  const reset = useCallback(
+    (...fields) => {
       if (fields.length === 0) {
         setData(defaults)
       } else {
-        setData(
+        setData((data) =>
           (Object.keys(defaults) as Array<keyof TForm>)
             .filter((key) => fields.includes(key))
             .reduce(
@@ -214,7 +211,11 @@ export default function useForm<TForm extends FormDataType>(
         )
       }
     },
-    setError(fieldOrFields: keyof TForm | Record<keyof TForm, string>, maybeValue?: string) {
+    [setData, defaults],
+  )
+
+  const setError = useCallback(
+    (fieldOrFields: keyof TForm | Record<keyof TForm, string>, maybeValue?: string) => {
       setErrors((errors) => {
         const newErrors = {
           ...errors,
@@ -226,7 +227,11 @@ export default function useForm<TForm extends FormDataType>(
         return newErrors
       })
     },
-    clearErrors(...fields) {
+    [setErrors, setHasErrors],
+  )
+
+  const clearErrors = useCallback(
+    (...fields) => {
       setErrors((errors) => {
         const newErrors = (Object.keys(errors) as Array<keyof TForm>).reduce(
           (carry, field) => ({
@@ -239,26 +244,49 @@ export default function useForm<TForm extends FormDataType>(
         return newErrors
       })
     },
+    [setErrors, setHasErrors],
+  )
+
+  const createSubmitMethod = (method) => (url, options) => {
+    submit(method, url, options)
+  }
+  const get = useCallback(createSubmitMethod('get'), [submit])
+  const post = useCallback(createSubmitMethod('post'), [submit])
+  const put = useCallback(createSubmitMethod('put'), [submit])
+  const patch = useCallback(createSubmitMethod('patch'), [submit])
+  const deleteMethod = useCallback(createSubmitMethod('delete'), [submit])
+
+  const cancel = useCallback(() => {
+    if (cancelToken.current) {
+      cancelToken.current.cancel()
+    }
+  }, [])
+
+  const transformFunction = useCallback((callback) => {
+    transform.current = callback
+  }, [])
+
+  return {
+    data,
+    setData: setDataFunction,
+    isDirty: !isEqual(data, defaults),
+    errors,
+    hasErrors,
+    processing,
+    progress,
+    wasSuccessful,
+    recentlySuccessful,
+    transform: transformFunction,
+    setDefaults: setDefaultsFunction,
+    reset,
+    setError,
+    clearErrors,
     submit,
-    get(url, options) {
-      submit('get', url, options)
-    },
-    post(url, options) {
-      submit('post', url, options)
-    },
-    put(url, options) {
-      submit('put', url, options)
-    },
-    patch(url, options) {
-      submit('patch', url, options)
-    },
-    delete(url, options) {
-      submit('delete', url, options)
-    },
-    cancel() {
-      if (cancelToken.current) {
-        cancelToken.current.cancel()
-      }
-    },
+    get,
+    post,
+    put,
+    patch,
+    delete: deleteMethod,
+    cancel,
   }
 }