refactor: drop isFirstLoad to use isLoading only (#613)

Author: DorianMaliszewski

packages/use-dataloader/README.md

@@ -123,11 +123,16 @@ function MyComponent() {
     fakePromise,
   )
 
-  // Will be true during the promise
-  if (isLoading) {
+  // This is the first time we load the data
+  if (isLoading && !data) {
     return <div>Loading...</div>
   }
 
+  // This happen when you already load the data but want to reload it
+  if (isLoading && data) {
+    return <div>Reloading...</div>
+  }
+
   // Will be true when the promise is resolved
   if (isSuccess) {
     // Will display "test" in the the div
@@ -233,13 +238,11 @@ const useDataLoader = (
 |   Property   |                                                      Description                                                      |
 | :----------: | :-------------------------------------------------------------------------------------------------------------------: |
 |    isIdle    |                                         `true` if the request is not launched                                         |
-|  isLoading   |                                           `true` if the request is launched                                           |
+|  isLoading   |                    `true` if the request is launched **or** enabled is `true` and isIdle is `true`                    |
 |  isSuccess   |                                      `true`if the request finished successfully                                       |
 |   isError    |                                         `true` if the request throw an error                                          |
 |  isPolling   | `true` if the request if `enabled` is true, `pollingInterval` is defined and the status is `isLoading` or `isSuccess` |
 | previousData |                             if `keepPreviousData` is true it return the last data fetched                             |
 |     data     |     return the `initialData` if no data is fetched or not present in the cache otherwise return the data fetched      |
 |    error     |                                      return the error occured during the request                                      |
 |    reload    |                            allow you to reload the data (it doesn't clear the actual data)                            |
-
-

packages/use-dataloader/src/types.ts

@@ -53,7 +53,6 @@ export interface UseDataLoaderResult<T = unknown> {
   isLoading: boolean
   isPolling: boolean
   isSuccess: boolean
-  isFirstLoad: boolean
   previousData?: T
   reload: () => Promise<void>
 }

packages/use-dataloader/src/useDataLoader.ts

@@ -85,8 +85,10 @@ const useDataLoader = <T>(
   const cancelMethodRef = useRef<(() => void) | undefined>(request?.cancel)
 
   const isLoading = useMemo(
-    () => request.status === StatusEnum.LOADING,
-    [request.status],
+    () =>
+      (enabled && request.status === StatusEnum.IDLE) ||
+      request.status === StatusEnum.LOADING,
+    [request.status, enabled],
   )
   const isIdle = useMemo(
     () => request.status === StatusEnum.IDLE,
@@ -105,11 +107,6 @@ const useDataLoader = <T>(
     [isSuccess, isLoading, enabled, pollingInterval],
   )
 
-  const isFirstLoad = useMemo(
-    () => (enabled && isIdle) || isLoading,
-    [isLoading, isIdle, enabled],
-  )
-
   useEffect(() => {
     if (enabled) {
       // launch should never throw
@@ -160,7 +157,6 @@ const useDataLoader = <T>(
     data: request.getData() || (initialData as T),
     error: request?.error,
     isError,
-    isFirstLoad,
     isIdle,
     isLoading,
     isPolling,