feat(typescript-types): Adapt Get to KeyPaths and KeyPath changes

packages/typescript-types/src/get.ts

@@ -1,25 +1,30 @@
-import type { If } from './if.js'
 import type { KeyPath } from './key-path.js'
-import type { KeyPaths } from './key-paths.js'
+import type { NonContainerType } from './non-container-type.js'
+import type { KeyPaths, KeyPaths_Options } from './key-paths.js'
 
-type FilterUndefined<T> = T extends undefined ? never : T
-type FilterNull<T> = T extends null ? never : T
-type FilterUndefinedAndNull<T> = FilterUndefined<FilterNull<T>>
+type ExtractFromForKey<Obj, Rest, ResultType = never> = Obj extends unknown
+	? never
+	: Obj extends undefined
+		? never
+		: Obj extends NonContainerType
+			? Obj | ResultType
+			: GetByKeyPath<Obj, Rest, ResultType>
 
-type ExtractFromForKey<Obj, Key, Rest> = Key extends keyof Obj
-	? Obj[Key] extends Record<PropertyKey, unknown>
-		? GetByKeyPath<Obj[Key], Rest>
-		: Obj[Key]
-	: Key extends keyof FilterUndefinedAndNull<Obj>
-		? FilterUndefinedAndNull<Obj>[Key] | undefined
-		: undefined
+type GetByKeyPath<Obj, Keys, ResultType = never> = Keys extends []
+	? Obj
+	: Keys extends [infer Key, ...infer Rest]
+		? Key extends keyof Obj
+			? ExtractFromForKey<Obj[Key], Rest, ResultType>
+			: Key extends `${infer Key}?`
+				? Key extends keyof Obj
+					? ExtractFromForKey<Obj[Key], Rest, ResultType | undefined>
+					: never
+				: never
+		: never
 
-type HasNoMoreKeys<K> = K extends [] ? true : false
-
-type GetByKeyPath<Obj, Keys> = If<
-	HasNoMoreKeys<Keys>,
-	Obj,
-	Keys extends [infer Key, ...infer Rest] ? ExtractFromForKey<Obj, Key, Rest> : never
->
-
-export type Get<O extends object, P extends KeyPaths<O>> = GetByKeyPath<O, KeyPath<P>>
+export type Get<
+	O,
+	P extends KeyPaths<O, Options, Filter>,
+	Options extends KeyPaths_Options = {},
+	Filter = null | undefined
+> = GetByKeyPath<O, KeyPath<P>>

packages/typescript-types/test/get.tst.ts

@@ -1,19 +1,29 @@
 import type { Get } from '@/get.js'
 import { expect } from 'tstyche'
 
-interface Example1 {
-	requiredKey: number
-	optionalKey?: number
-	unknownNonOptionalKey: unknown
-	undefinedNonOptionalKey: undefined
+interface ExampleObject {
+	nullvalue: null
+	simplevalue: string
+	unknownKey: unknown
 	neverKey: never
-	subkey: {
+	undefinedKey: undefined
+	undefinedOptionalKey?: undefined
+	optionalKey?: string
+	objectKey: {
 		name: string
-		age: number
+		age?: number
 	}
+	optionalObjectKey?: {
+		name: string
+		age?: number
+	}
+	arrayKey: [{ name: string; age: number }, 1]
+	optionalArrayKey?: [{ name: string }, { age?: number }]
 }
 
-expect<Get<Example1, 'requiredKey'>>().type.toBe<number>()
-expect<Get<Example1, 'optionalKey'>>().type.toBe<number | undefined>()
-expect<Get<Example1, 'subkey.age'>>().type.toBe<number>()
-expect<Get<Example1, 'unknownNonOptionalKey'>>().type.toBe<unknown>()
+// type T = any extends never ? true : false
+// type A = Get<ExampleObject, 'simplevalue'>
+expect<Get<ExampleObject, 'simplevalue'>>().type.toBe<string>()
+expect<Get<ExampleObject, 'optionalObjectKey?.name', {}, never>>().type.toBe<string | undefined>()
+expect<Get<ExampleObject, 'optionalObjectKey?.age?', {}, never>>().type.toBe<number | undefined>()
+expect<Get<ExampleObject, 'optionalArrayKey?.0.name', {}, never>>().type.toBe<string | undefined>()