Schema: Add recurseIntoArrays option (#960)

Co-authored-by: Grigoris Christainas <[email protected]>
sindresorhus · Nov 27, 2024 · fbbb8ba · fbbb8ba
1 parent d7b692b
commit fbbb8ba
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Showing 3 changed files with 125 additions and 8 deletions.
diff --git a/index.d.ts b/index.d.ts
@@ -66,7 +66,7 @@ export type {SimplifyDeep} from './source/simplify-deep';
 export type {Jsonify} from './source/jsonify';
 export type {Jsonifiable} from './source/jsonifiable';
 export type {StructuredCloneable} from './source/structured-cloneable';
-export type {Schema} from './source/schema';
+export type {Schema, SchemaOptions} from './source/schema';
 export type {LiteralToPrimitive} from './source/literal-to-primitive';
 export type {LiteralToPrimitiveDeep} from './source/literal-to-primitive-deep';
 export type {

diff --git a/source/schema.d.ts b/source/schema.d.ts
@@ -19,6 +19,7 @@ interface User {
 	created: Date;
 	active: boolean;
 	passwordHash: string;
+	attributes: ['Foo', 'Bar']
 }
 
 type UserMask = Schema<User, 'mask' | 'hide' | 'show'>;
@@ -32,12 +33,13 @@ const userMaskSettings: UserMask = {
 	created: 'show',
 	active: 'show',
 	passwordHash: 'hide',
+	attributes: ['mask', 'show']
 }
 ```
 
 @category Object
 */
-export type Schema<ObjectType, ValueType> = ObjectType extends string
+export type Schema<ObjectType, ValueType, Options extends SchemaOptions = {}> = ObjectType extends string
 	? ValueType
 	: ObjectType extends Map<unknown, unknown>
 		? ValueType
@@ -48,7 +50,9 @@ export type Schema<ObjectType, ValueType> = ObjectType extends string
 				: ObjectType extends ReadonlySet<unknown>
 					? ValueType
 					: ObjectType extends Array<infer U>
-						? Array<Schema<U, ValueType>>
+						? Options['recurseIntoArrays'] extends false | undefined
+							? ValueType
+							: Array<Schema<U, ValueType>>
 						: ObjectType extends (...arguments_: unknown[]) => unknown
 							? ValueType
 							: ObjectType extends Date
@@ -58,14 +62,53 @@ export type Schema<ObjectType, ValueType> = ObjectType extends string
 									: ObjectType extends RegExp
 										? ValueType
 										: ObjectType extends object
-											? SchemaObject<ObjectType, ValueType>
+											? SchemaObject<ObjectType, ValueType, Options>
 											: ValueType;
 
 /**
 Same as `Schema`, but accepts only `object`s as inputs. Internal helper for `Schema`.
 */
-type SchemaObject<ObjectType extends object, K> = {
-	[KeyType in keyof ObjectType]: ObjectType[KeyType] extends readonly unknown[] | unknown[]
-		? Schema<ObjectType[KeyType], K>
-		: Schema<ObjectType[KeyType], K> | K;
+type SchemaObject<
+	ObjectType extends object,
+	K,
+	Options extends SchemaOptions,
+> = {
+	[KeyType in keyof ObjectType]: ObjectType[KeyType] extends
+	| readonly unknown[]
+	| unknown[]
+		? Options['recurseIntoArrays'] extends false | undefined
+			? K
+			: Schema<ObjectType[KeyType], K, Options>
+		: Schema<ObjectType[KeyType], K, Options> | K;
+};
+
+/**
+@see Schema
+*/
+export type SchemaOptions = {
+	/**
+	By default, this affects elements in array and tuple types. You can change this by passing `{recurseIntoArrays: false}` as the third type argument:
+	- If `recurseIntoArrays` is set to `true` (default), array elements will be recursively processed as well.
+	- If `recurseIntoArrays` is set to `false`, arrays will not be recursively processed, and the entire array will be replaced with the given value type.
+
+	@example
+	```
+	type UserMask = Schema<User, 'mask' | 'hide' | 'show', {recurseIntoArrays: false}>;
+
+	const userMaskSettings: UserMask = {
+		id: 'show',
+		name: {
+			firstname: 'show',
+			lastname: 'mask',
+		},
+		created: 'show',
+		active: 'show',
+		passwordHash: 'hide',
+		attributes: 'hide'
+	}
+	```
+
+	@default true
+	*/
+	readonly recurseIntoArrays?: boolean | undefined;
 };
diff --git a/test-d/schema.ts b/test-d/schema.ts
@@ -126,3 +126,77 @@ expectType<ComplexOption>(complexBarSchema.readonlySet);
 expectType<readonly ComplexOption[]>(complexBarSchema.readonlyArray);
 expectType<readonly [ComplexOption]>(complexBarSchema.readonlyTuple);
 expectType<ComplexOption>(complexBarSchema.regExp);
+
+// With Options and `recurseIntoArrays` set to `false`
+type FooSchemaWithOptionsNoRecurse = Schema<typeof foo, FooOption, {recurseIntoArrays: false | undefined}>;
+
+const fooSchemaWithOptionsNoRecurse: FooSchemaWithOptionsNoRecurse = {
+	baz: 'A',
+	bar: {
+		function: 'A',
+		object: {key: 'A'},
+		string: 'A',
+		number: 'A',
+		boolean: 'A',
+		symbol: 'A',
+		map: 'A',
+		set: 'A',
+		array: 'A',
+		tuple: 'A',
+		objectArray: 'A',
+		readonlyMap: 'A',
+		readonlySet: 'A',
+		readonlyArray: 'A' as const,
+		readonlyTuple: 'A' as const,
+		regExp: 'A',
+	},
+};
+
+expectNotAssignable<FooSchemaWithOptionsNoRecurse>(foo);
+expectNotAssignable<FooSchemaWithOptionsNoRecurse>({key: 'value'});
+expectNotAssignable<FooSchemaWithOptionsNoRecurse>(new Date());
+expectType<FooOption>(fooSchemaWithOptionsNoRecurse.baz);
+
+const barSchemaWithOptionsNoRecurse = fooSchemaWithOptionsNoRecurse.bar as Schema<typeof foo['bar'], FooOption, {recurseIntoArrays: false | undefined}>;
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.function);
+expectType<FooOption | {key: FooOption}>(barSchemaWithOptionsNoRecurse.object);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.string);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.number);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.boolean);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.symbol);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.map);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.set);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.array);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.tuple);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.objectArray);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.readonlyMap);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.readonlySet);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.readonlyArray);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.readonlyTuple);
+expectType<FooOption>(barSchemaWithOptionsNoRecurse.regExp);
+
+// With Options and `recurseIntoArrays` set to `true`
+type FooSchemaWithOptionsRecurse = Schema<typeof foo, FooOption, {recurseIntoArrays: true}>;
+
+expectNotAssignable<FooSchemaWithOptionsRecurse>(foo);
+expectNotAssignable<FooSchemaWithOptionsRecurse>({key: 'value'});
+expectNotAssignable<FooSchemaWithOptionsRecurse>(new Date());
+expectType<FooOption>(fooSchema.baz);
+
+const barSchemaWithOptionsRecurse = fooSchema.bar as Schema<typeof foo['bar'], FooOption, {recurseIntoArrays: true}>;
+expectType<FooOption>(barSchemaWithOptionsRecurse.function);
+expectType<FooOption | {key: FooOption}>(barSchemaWithOptionsRecurse.object);
+expectType<FooOption>(barSchemaWithOptionsRecurse.string);
+expectType<FooOption>(barSchemaWithOptionsRecurse.number);
+expectType<FooOption>(barSchemaWithOptionsRecurse.boolean);
+expectType<FooOption>(barSchemaWithOptionsRecurse.symbol);
+expectType<FooOption>(barSchemaWithOptionsRecurse.map);
+expectType<FooOption>(barSchemaWithOptionsRecurse.set);
+expectType<FooOption[]>(barSchemaWithOptionsRecurse.array);
+expectType<FooOption[]>(barSchemaWithOptionsRecurse.tuple);
+expectType<Array<{key: FooOption}>>(barSchemaWithOptionsRecurse.objectArray);
+expectType<FooOption>(barSchemaWithOptionsRecurse.readonlyMap);
+expectType<FooOption>(barSchemaWithOptionsRecurse.readonlySet);
+expectType<readonly FooOption[]>(barSchemaWithOptionsRecurse.readonlyArray);
+expectType<readonly [FooOption]>(barSchemaWithOptionsRecurse.readonlyTuple);
+expectType<FooOption>(barSchemaWithOptionsRecurse.regExp);