From 06bd61fc7a7f01952db528364d79eff92ecb3cfe Mon Sep 17 00:00:00 2001
From: Lucas Lois <lucasloisp@gmail.com>
Date: Fri, 4 Aug 2023 21:38:16 -0300
Subject: [PATCH] feat: makes NavigationContainerRef.getCurrentRoute type safe

---
 example/__typechecks__/common.check.tsx | 34 +++++++++++++++++++++++++
 example/__typechecks__/static.check.tsx | 26 +++++++++++++++++++
 packages/core/src/types.tsx             | 14 +++++++++-
 3 files changed, 73 insertions(+), 1 deletion(-)

diff --git a/example/__typechecks__/common.check.tsx b/example/__typechecks__/common.check.tsx
index 85fd35168b..fa640cf2e4 100644
--- a/example/__typechecks__/common.check.tsx
+++ b/example/__typechecks__/common.check.tsx
@@ -8,8 +8,10 @@ import type {
 } from '@react-navigation/drawer';
 import type {
   CompositeScreenProps,
+  NavigationContainerRef,
   NavigationHelpers,
   NavigatorScreenParams,
+  Route,
 } from '@react-navigation/native';
 import type { StackNavigationOptions } from '@react-navigation/stack';
 import {
@@ -350,3 +352,35 @@ export const ThirdScreen = ({
   // @ts-expect-error
   if (ScreenName === 'NoParams') navigation.navigate(ScreenName, { id: '123' });
 };
+
+/**
+ * Check for errors on getCurrentRoute
+ */
+declare const navigationRef: NavigationContainerRef<RootStackParamList>;
+const route = navigationRef.getCurrentRoute()!;
+
+switch (route.name) {
+  case 'PostDetails':
+    expectTypeOf(route.params).toMatchTypeOf<{
+      id: string;
+      section?: string;
+    }>();
+    break;
+  case 'Login':
+    expectTypeOf(route.params).toMatchTypeOf<undefined>();
+    break;
+  case 'Account':
+    expectTypeOf(route.params).toMatchTypeOf<undefined>();
+    break;
+  case 'Popular':
+    expectTypeOf(route.params).toMatchTypeOf<{
+      filter: 'day' | 'week' | 'month';
+    }>();
+    break;
+}
+
+declare const navigationRefUntyped: NavigationContainerRef<string>;
+
+expectTypeOf(navigationRefUntyped.getCurrentRoute()).toMatchTypeOf<
+  Route<string> | undefined
+>();
diff --git a/example/__typechecks__/static.check.tsx b/example/__typechecks__/static.check.tsx
index 83019ef7c4..7a303b3278 100644
--- a/example/__typechecks__/static.check.tsx
+++ b/example/__typechecks__/static.check.tsx
@@ -1,5 +1,6 @@
 import { createBottomTabNavigator } from '@react-navigation/bottom-tabs';
 import type {
+  NavigationContainerRef,
   NavigationProp,
   StaticParamList,
   StaticScreenProps,
@@ -196,3 +197,28 @@ createStackNavigator({});
 createStackNavigator({
   screens: {},
 });
+
+/**
+ * Check for errors on getCurrentRoute
+ */
+declare const navigationRef: NavigationContainerRef<ParamList>;
+const route = navigationRef.getCurrentRoute()!;
+
+switch (route.name) {
+  case 'Profile':
+    expectTypeOf(route.params).toMatchTypeOf<{
+      user: string;
+    }>();
+    break;
+  case 'Settings':
+    expectTypeOf(route.params).toMatchTypeOf<undefined>();
+    break;
+  case 'Login':
+    expectTypeOf(route.params).toMatchTypeOf<undefined>();
+    break;
+  case 'Register':
+    expectTypeOf(route.params).toMatchTypeOf<{
+      method: 'email' | 'social';
+    }>();
+    break;
+}
diff --git a/packages/core/src/types.tsx b/packages/core/src/types.tsx
index f2562c9e8c..21c8ec3be3 100644
--- a/packages/core/src/types.tsx
+++ b/packages/core/src/types.tsx
@@ -648,6 +648,18 @@ export type NavigationContainerEventMap = {
   };
 };
 
+type ParamListRoute<ParamList extends ParamListBase> = {
+  [RouteName in keyof ParamList]: ParamList[RouteName] extends NavigatorScreenParams<
+    infer T extends ParamListBase
+  >
+    ? ParamListRoute<T>
+    : Route<Extract<RouteName, string>, ParamList[RouteName]>;
+}[keyof ParamList];
+
+type MaybeParamListRoute<ParamList extends {}> = ParamList extends ParamListBase
+  ? ParamListRoute<ParamList>
+  : Route<string>;
+
 export type NavigationContainerRef<ParamList extends {}> =
   NavigationHelpers<ParamList> &
     EventConsumer<NavigationContainerEventMap> & {
@@ -664,7 +676,7 @@ export type NavigationContainerRef<ParamList extends {}> =
       /**
        * Get the currently focused navigation route.
        */
-      getCurrentRoute(): Route<string> | undefined;
+      getCurrentRoute(): MaybeParamListRoute<ParamList> | undefined;
       /**
        * Get the currently focused route's options.
        */