Only apply mapped types to un-branded types (reduxjs#3817)

alokreddy · Sep 30, 2020 · 54f9c5f · 54f9c5f
1 parent 2ee57c8
commit 54f9c5f
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Showing 2 changed files with 28 additions and 11 deletions.
diff --git a/src/types/store.ts b/src/types/store.ts
@@ -53,7 +53,9 @@ export type PreloadedState<S> = Required<S> extends {
  }
  : never
  : {
- [K in keyof S]: S[K] extends object ? PreloadedState<S[K]> : S[K]
+ [K in keyof S]: S[K] extends string | number | boolean | symbol
+ ? S[K]
+ : PreloadedState<S[K]>
  }
 
 /**

diff --git a/test/typescript/store.ts b/test/typescript/store.ts
@@ -10,12 +10,16 @@ import {
 } from '../..'
 import 'symbol-observable'
 
+type BrandedString = string & { _brand: 'type' }
+const brandedString = 'a string' as BrandedString
+
 type State = {
  a: 'a'
  b: {
  c: 'c'
  d: 'd'
  }
+ e: BrandedString
 }
 
 /* extended state */
@@ -24,7 +28,8 @@ const noExtend: ExtendState<State, never> = {
  b: {
  c: 'c',
  d: 'd'
- }
+ },
+ e: brandedString
 }
 // typings:expect-error
 const noExtendError: ExtendState<State, never> = {
@@ -33,7 +38,8 @@ const noExtendError: ExtendState<State, never> = {
  c: 'c',
  d: 'd'
  },
- e: 'oops'
+ e: brandedString,
+ f: 'oops'
 }
 
 const yesExtend: ExtendState<State, { yes: 'we can' }> = {
@@ -42,6 +48,7 @@ const yesExtend: ExtendState<State, { yes: 'we can' }> = {
  c: 'c',
  d: 'd'
  },
+ e: brandedString,
  yes: 'we can'
 }
 // typings:expect-error
@@ -50,7 +57,8 @@ const yesExtendError: ExtendState<State, { yes: 'we can' }> = {
  b: {
  c: 'c',
  d: 'd'
- }
+ },
+ e: brandedString
 }
 
 interface DerivedAction extends Action {
@@ -64,7 +72,8 @@ const reducer: Reducer<State> = (
  b: {
  c: 'c',
  d: 'd'
- }
+ },
+ e: brandedString
  },
  action: Action
 ): State => {
@@ -77,7 +86,8 @@ const reducerWithAction: Reducer<State, DerivedAction> = (
  b: {
  c: 'c',
  d: 'd'
- }
+ },
+ e: brandedString
  },
  action: DerivedAction
 ): State => {
@@ -95,17 +105,20 @@ const arrayReducer = (state: any[] = []) => state || []
 const storeWithArrayState: Store<any[]> = createStore(arrayReducer)
 const storeWithPreloadedState: Store<State> = createStore(reducer, {
  a: 'a',
- b: { c: 'c', d: 'd' }
+ b: { c: 'c', d: 'd' },
+ e: brandedString
 })
 // typings:expect-error
 const storeWithBadPreloadedState: Store<State> = createStore(reducer, {
- b: { c: 'c' }
+ b: { c: 'c' },
+ e: brandedString
 })
 
 const storeWithActionReducer = createStore(reducerWithAction)
 const storeWithActionReducerAndPreloadedState = createStore(reducerWithAction, {
  a: 'a',
- b: { c: 'c', d: 'd' }
+ b: { c: 'c', d: 'd' },
+ e: brandedString
 })
 funcWithStore(storeWithActionReducer)
 funcWithStore(storeWithActionReducerAndPreloadedState)
@@ -114,7 +127,8 @@ funcWithStore(storeWithActionReducerAndPreloadedState)
 const storeWithActionReducerAndBadPreloadedState = createStore(
  reducerWithAction,
  {
- b: { c: 'c' }
+ b: { c: 'c' },
+ e: brandedString
  }
 )
 
@@ -126,7 +140,8 @@ const storeWithPreloadedStateAndEnhancer: Store<State> = createStore(
  reducer,
  {
  a: 'a',
- b: { c: 'c', d: 'd' }
+ b: { c: 'c', d: 'd' },
+ e: brandedString
  },
  enhancer
 )