From fa0c86e2fef9b43920e168cfb2f5a022f32c9b24 Mon Sep 17 00:00:00 2001
From: Pierre Zimmermann
 <64224599+pierrezimmermannbam@users.noreply.github.com>
Date: Wed, 19 Jul 2023 13:34:22 +0200
Subject: [PATCH] fix: correct type inference for props when initialProps is
 used (#1421)

* fix: correct type inference for props when initialProps is used

* Update src/__tests__/renderHook.test.tsx

* refactor: simplify type of Renderhook options

---------

Co-authored-by: pierrezimmermann <pierrez@nam.tech>
Co-authored-by: Maciej Jastrzebski <mdjastrzebski@gmail.com>
---
 src/__tests__/renderHook.test.tsx | 34 +++++++++++++++++++++++++++++++
 src/renderHook.tsx                | 14 ++++---------
 2 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/src/__tests__/renderHook.test.tsx b/src/__tests__/renderHook.test.tsx
index 389f38ffa..6e9f231a5 100644
--- a/src/__tests__/renderHook.test.tsx
+++ b/src/__tests__/renderHook.test.tsx
@@ -60,3 +60,37 @@ test('allows wrapper components', async () => {
 
   expect(result.current).toEqual('provided');
 });
+
+const useMyHook = (param: number | undefined) => {
+  return param;
+};
+
+test('props type is infered correctly when initial props is defined', () => {
+  const { result, rerender } = renderHook(
+    (num: number | undefined) => useMyHook(num),
+    {
+      initialProps: 5,
+    }
+  );
+
+  expect(result.current).toBe(5);
+
+  rerender(6);
+
+  expect(result.current).toBe(6);
+});
+
+test('props type is inferred correctly when initial props is explicitly undefined', () => {
+  const { result, rerender } = renderHook(
+    (num: number | undefined) => useMyHook(num),
+    {
+      initialProps: undefined,
+    }
+  );
+
+  expect(result.current).toBeUndefined();
+
+  rerender(6);
+
+  expect(result.current).toBe(6);
+});
diff --git a/src/renderHook.tsx b/src/renderHook.tsx
index 35965d00a..ada485dc4 100644
--- a/src/renderHook.tsx
+++ b/src/renderHook.tsx
@@ -8,16 +8,10 @@ export type RenderHookResult<Result, Props> = {
   unmount: () => void;
 };
 
-export type RenderHookOptions<Props> = Props extends
-  | object
-  | string
-  | number
-  | boolean
-  ? {
-      initialProps: Props;
-      wrapper?: ComponentType<any>;
-    }
-  : { wrapper?: ComponentType<any>; initialProps?: never } | undefined;
+export type RenderHookOptions<Props> = {
+  initialProps?: Props;
+  wrapper?: ComponentType<any>;
+};
 
 export function renderHook<Result, Props>(
   renderCallback: (props: Props) => Result,