Merge branch 'master' into feature/prettier

# Conflicts:
#	src/core/types.ts

Author: TkDodo

docs/src/pages/guides/mutations.md

@@ -44,7 +44,7 @@ A mutation can only be in one of the following states at any given moment:
 - `isError` or `status === 'error'` - The mutation encountered an error
 - `isSuccess` or `status === 'success'` - The mutation was successful and mutation data is available
 
-Beyond those primary state, more information is available depending on the state the mutation:
+Beyond those primary states, more information is available depending on the state of the mutation:
 
 - `error` - If the mutation is in an `isError` state, the error is available via the `error` property.
 - `data` - If the mutation is in a `success` state, the data is available via the `data` property.

docs/src/pages/guides/placeholder-query-data.md

@@ -43,7 +43,7 @@ In some circumstances, you may be able to provide the placeholder data for a que
 
 ```js
 function Todo({ blogPostId }) {
-  const result = useQuery(['blogPost', blogPostId], () => fetch('/blogPosts'), {
+  const result = useQuery(['blogPost', blogPostId], () => fetch(`/blogPosts/${blogPostId}`), {
     placeholderData: () => {
       // Use the smaller/preview version of the blogPost from the 'blogPosts' query as the placeholder data for this blogPost query
       return queryClient

docs/src/pages/reference/useMutation.md

@@ -46,15 +46,15 @@ mutate(variables, {
   - This function will fire before the mutation function is fired and is passed the same variables the mutation function would receive
   - Useful to perform optimistic updates to a resource in hopes that the mutation succeeds
   - The value returned from this function will be passed to both the `onError` and `onSettled` functions in the event of a mutation failure and can be useful for rolling back optimistic updates.
-- `onSuccess: (data: TData, variables: TVariables, context?: TContext) => Promise<void> | void`
+- `onSuccess: (data: TData, variables: TVariables, context?: TContext) => Promise<unknown> | void`
   - Optional
   - This function will fire when the mutation is successful and will be passed the mutation's result.
   - If a promise is returned, it will be awaited and resolved before proceeding
-- `onError: (err: TError, variables: TVariables, context?: TContext) => Promise<void> | void`
+- `onError: (err: TError, variables: TVariables, context?: TContext) => Promise<unknown> | void`
   - Optional
   - This function will fire if the mutation encounters an error and will be passed the error.
   - If a promise is returned, it will be awaited and resolved before proceeding
-- `onSettled: (data: TData, error: TError, variables: TVariables, context?: TContext) => Promise<void> | void`
+- `onSettled: (data: TData, error: TError, variables: TVariables, context?: TContext) => Promise<unknown> | void`
   - Optional
   - This function will fire when the mutation is either successfully fetched or encounters an error and be passed either the data or error
   - If a promise is returned, it will be awaited and resolved before proceeding

src/core/types.ts

@@ -485,18 +485,18 @@ export interface MutationOptions<
     data: TData,
     variables: TVariables,
     context: TContext
-  ) => Promise<void> | void
+  ) => Promise<unknown> | void
   onError?: (
     error: TError,
     variables: TVariables,
     context: TContext | undefined
-  ) => Promise<void> | void
+  ) => Promise<unknown> | void
   onSettled?: (
     data: TData | undefined,
     error: TError | null,
     variables: TVariables,
     context: TContext | undefined
-  ) => Promise<void> | void
+  ) => Promise<unknown> | void
   retry?: RetryValue<TError>
   retryDelay?: RetryDelayValue<TError>
   _defaulted?: boolean
@@ -521,18 +521,18 @@ export interface MutateOptions<
     data: TData,
     variables: TVariables,
     context: TContext
-  ) => Promise<void> | void
+  ) => Promise<unknown> | void
   onError?: (
     error: TError,
     variables: TVariables,
     context: TContext | undefined
-  ) => Promise<void> | void
+  ) => Promise<unknown> | void
   onSettled?: (
     data: TData | undefined,
     error: TError | null,
     variables: TVariables,
     context: TContext | undefined
-  ) => Promise<void> | void
+  ) => Promise<unknown> | void
 }
 
 export type MutateFunction<

src/react/types.ts

@@ -82,18 +82,18 @@ export interface UseMutationOptions<
     data: TData,
     variables: TVariables,
     context: TContext | undefined
-  ) => Promise<void> | void
+  ) => Promise<unknown> | void
   onError?: (
     error: TError,
     variables: TVariables,
     context: TContext | undefined
-  ) => Promise<void> | void
+  ) => Promise<unknown> | void
   onSettled?: (
     data: TData | undefined,
     error: TError | null,
     variables: TVariables,
     context: TContext | undefined
-  ) => Promise<void> | void
+  ) => Promise<unknown> | void
   retry?: RetryValue<TError>
   retryDelay?: RetryDelayValue<TError>
   useErrorBoundary?: boolean