type-fest - npm Package Compare versions

Comparing version 4.6.0 to 4.7.0

source/paths.d.ts

+import type {ToString} from './internal';
+import type {EmptyObject} from './empty-object';
+import type {IsAny} from './is-any';
+import type {IsNever} from './is-never';
+import type {UnknownArray} from './unknown-array';
+import type {UnknownRecord} from './unknown-record';
+
+/**
+Return the part of the given array with a fixed index.
+
+@example
+```
+type A = [string, number, boolean, ...string[]];
+type B = FilterFixedIndexArray<A>;
+//=> [string, number, boolean]
+```
+*/
+type FilterFixedIndexArray<T extends UnknownArray, Result extends UnknownArray = []> =
+	number extends T['length'] ?
+		T extends readonly [infer U, ...infer V]
+			? FilterFixedIndexArray<V, [...Result, U]>
+			: Result
+		: T;
+
+/**
+Return the part of the given array with a non-fixed index.
+
+@example
+```
+type A = [string, number, boolean, ...string[]];
+type B = FilterNotFixedIndexArray<A>;
+//=> string[]
+```
+*/
+type FilterNotFixedIndexArray<T extends UnknownArray> =
+T extends readonly [...FilterFixedIndexArray<T>, ...infer U]
+	? U
+	: [];
+
+/**
+Generate a union of all possible paths to properties in the given object.
+
+It also works with arrays.
+
+Use-case: You want a type-safe way to access deeply nested properties in an object.
+
+@example
+```
+import type {Paths} from 'type-fest';
+
+type Project = {
+	filename: string;
+	listA: string[];
+	listB: [{filename: string}];
+	folder: {
+		subfolder: {
+			filename: string;
+		};
+	};
+};
+
+type ProjectPaths = Paths<Project>;
+//=> 'filename' | 'listA' | 'listB' | 'folder' | `listA.${number}` | 'listB.0' | 'listB.0.filename' | 'folder.subfolder' | 'folder.subfolder.filename'
+
+declare function open<Path extends ProjectPaths>(path: Path): void;
+
+open('filename'); // Pass
+open('folder.subfolder'); // Pass
+open('folder.subfolder.filename'); // Pass
+open('foo'); // TypeError
+
+// Also works with arrays
+open('listA.1'); // Pass
+open('listB.0'); // Pass
+open('listB.1'); // TypeError. Because listB only has one element.
+```
+
+@category Object
+@category Array
+*/
+export type Paths<T extends UnknownRecord | UnknownArray> =
+	IsAny<T> extends true
+		? never
+		: T extends UnknownArray
+			? number extends T['length']
+				// We need to handle the fixed and non-fixed index part of the array separately.
+				? InternalPaths<FilterFixedIndexArray<T>>
+				| InternalPaths<Array<FilterNotFixedIndexArray<T>[number]>>
+				: InternalPaths<T>
+			: InternalPaths<T>;
+
+export type InternalPaths<_T extends UnknownRecord | UnknownArray, T = Required<_T>> =
+	T extends EmptyObject | readonly []
+		? never
+		: {
+			[Key in keyof T]:
+			Key extends string | number // Limit `Key` to string or number.
+				? T[Key] extends UnknownRecord | UnknownArray
+					? (
+						IsNever<Paths<T[Key]>> extends false
+							// If `Key` is a number, return `Key | `${Key}``, because both `array[0]` and `array['0']` work.
+							? Key | ToString<Key> | `${Key}.${Paths<T[Key]>}`
+							: Key | ToString<Key>
+					)
+					: Key | ToString<Key>
+				: never
+		}[keyof T & (T extends UnknownArray ? number : unknown)];

source/pick-deep.d.ts

+import type {BuildObject, BuildTuple, ToString} from './internal';
+import type {Paths} from './paths';
+import type {Simplify} from './simplify.d';
+import type {UnionToIntersection} from './union-to-intersection.d';
+import type {UnknownArray} from './unknown-array';
+import type {UnknownRecord} from './unknown-record.d';
+
+/**
+Pick properties from a deeply-nested object.
+
+It supports recursing into arrays.
+
+Use-case: Distill complex objects down to the components you need to target.
+
+@example
+```
+import type {PickDeep, PartialDeep} from 'type-fest';
+
+type Configuration = {
+	userConfig: {
+		name: string;
+		age: number;
+		address: [
+			{
+				city1: string;
+				street1: string;
+			},
+			{
+				city2: string;
+				street2: string;
+			}
+		]
+	};
+	otherConfig: any;
+};
+
+type NameConfig = PickDeep<Configuration, 'userConfig.name'>;
+// type NameConfig = {
+// 	userConfig: {
+// 	name: string;
+// };
+
+// Supports optional properties
+type User = PickDeep<PartialDeep<Configuration>, 'userConfig.name' | 'userConfig.age'>;
+// type User = {
+// 	userConfig?: {
+// 		name?: string;
+// 		age?: number;
+// 	};
+// };
+
+// Supports array
+type AddressConfig = PickDeep<Configuration, `userConfig.address.0`>;
+// type AddressConfig = {
+// 	userConfig: {
+// 		address: [{
+// 			city1: string;
+// 			street1: string;
+// 		}];
+// 	};
+// }
+
+// Supports recurse into array
+type Street = PickDeep<Configuration, `userConfig.address.1.street2`>;
+// type AddressConfig = {
+// 	userConfig: {
+// 		address: [
+// 			unknown,
+// 			{street2: string}
+// 		];
+// 	};
+// }
+```
+
+@category Object
+@category Array
+*/
+export type PickDeep<T extends UnknownRecord | UnknownArray, PathUnion extends Paths<T>> =
+	T extends UnknownRecord
+		? Simplify<UnionToIntersection<{
+			[P in PathUnion]: InternalPickDeep<T, P>;
+		}[PathUnion]>>
+		: T extends UnknownArray
+			? UnionToIntersection<{
+				[P in PathUnion]: InternalPickDeep<T, P>;
+			}[PathUnion]
+			>
+			: never;
+
+/**
+Pick an object/array from the given object/array by one path.
+*/
+type InternalPickDeep<
+	T extends UnknownRecord | UnknownArray,
+	Path extends string | number, // Checked paths, extracted from unchecked paths
+> =
+	T extends UnknownArray ? PickDeepArray<T, Path>
+		: T extends UnknownRecord ? Simplify<PickDeepObject<T, Path>>
+			: never;
+
+/**
+Pick an object from the given object by one path.
+*/
+type PickDeepObject<RecordType extends UnknownRecord, P extends string | number> =
+	P extends `${infer RecordKeyInPath}.${infer SubPath}`
+		? BuildObject<RecordKeyInPath, InternalPickDeep<NonNullable<RecordType[RecordKeyInPath]>, SubPath>, RecordType>
+		: P extends keyof RecordType | ToString<keyof RecordType> // Handle number keys
+			? BuildObject<P, RecordType[P], RecordType>
+			: never;
+
+/**
+Pick an array from the given array by one path.
+*/
+type PickDeepArray<ArrayType extends UnknownArray, P extends string | number> =
+	// Handle paths that are `${number}.${string}`
+	P extends `${infer ArrayIndex extends number}.${infer SubPath}`
+		// When `ArrayIndex` is equal to `number`
+		? number extends ArrayIndex
+			? ArrayType extends unknown[]
+				? Array<InternalPickDeep<NonNullable<ArrayType[number]>, SubPath>>
+				: ArrayType extends readonly unknown[]
+					? ReadonlyArray<InternalPickDeep<NonNullable<ArrayType[number]>, SubPath>>
+					: never
+			// When `ArrayIndex` is a number literal
+			: ArrayType extends unknown[]
+				? [...BuildTuple<ArrayIndex>, InternalPickDeep<NonNullable<ArrayType[ArrayIndex]>, SubPath>]
+				: ArrayType extends readonly unknown[]
+					? readonly [...BuildTuple<ArrayIndex>, InternalPickDeep<NonNullable<ArrayType[ArrayIndex]>, SubPath>]
+					: never
+		// When the path is equal to `number`
+		: P extends `${infer ArrayIndex extends number}`
+			// When `ArrayIndex` is `number`
+			? number extends ArrayIndex
+				? ArrayType
+				// When `ArrayIndex` is a number literal
+				: ArrayType extends unknown[]
+					? [...BuildTuple<ArrayIndex>, ArrayType[ArrayIndex]]
+					: ArrayType extends readonly unknown[]
+						? readonly [...BuildTuple<ArrayIndex>, ArrayType[ArrayIndex]]
+						: never
+			: never;

source/set-field-type.d.ts

+import type {Except} from './except';
+import type {Simplify} from './simplify';
+
+/**
+Create a type that changes the type of the given keys.
+
+Use-cases:
+- Creating variations of a base model.
+- Fixing incorrect external types.
+
+@see `Merge` if you need to change multiple properties to different types.
+
+@example
+```
+import type {SetFieldType} from 'type-fest';
+
+type MyModel = {
+	id: number;
+	createdAt: Date;
+	updatedAt: Date;
+};
+
+type MyModelApi = SetFieldType<MyModel, 'createdAt' | 'updatedAt', string>;
+// {
+// 	id: number;
+// 	createdAt: string;
+// 	updatedAt: string;
+// }
+```
+
+@category Object
+*/
+export type SetFieldType<BaseType, Keys extends keyof BaseType, NewType> =
+	Simplify<
+	Except<BaseType, Keys> &
+	Record<Keys, NewType>
+	>;

source/unknown-array.d.ts

+/**
+Represents an array with `unknown` value.
+
+Use case: You want a type that all arrays can be assigned to, but you don't care about the value.
+
+@example
+```
+import type {UnknownArray} from 'type-fest';
+
+type IsArray<T> = T extends UnknownArray ? true : false;
+
+type A = IsArray<['foo']>;
+//=> true
+
+type B = IsArray<readonly number[]>;
+//=> true
+
+type C = IsArray<string>;
+//=> false
+```
+
+@category Type
+@category Array
+*/
+export type UnknownArray = readonly unknown[];

index.d.ts

@@ -12,2 +12,3 @@ // Basic
 export type {UnknownRecord} from './source/unknown-record';
+export type {UnknownArray} from './source/unknown-array';
 export type {Except} from './source/except';
@@ -28,2 +29,3 @@ export type {TaggedUnion} from './source/tagged-union';
 export type {RequiredDeep} from './source/required-deep';
+export type {PickDeep} from './source/pick-deep';
 export type {PartialOnUndefinedDeep, PartialOnUndefinedDeepOptions} from './source/partial-on-undefined-deep';
@@ -106,2 +108,4 @@ export type {UndefinedOnPartialDeep} from './source/undefined-on-partial-deep';
 export type {ArrayValues} from './source/array-values';
+export type {SetFieldType} from './source/set-field-type';
+export type {Paths} from './source/paths';
 
@@ -108,0 +112,0 @@ // Template literal types

package.json

 {
 	"name": "type-fest",
-	"version": "4.6.0",
+	"version": "4.7.0",
 	"description": "A collection of essential TypeScript types",
@@ -14,2 +14,3 @@ "license": "(MIT OR CC0-1.0)",
 	"types": "./index.d.ts",
+	"sideEffects": false,
 	"engines": {
@@ -16,0 +17,0 @@ "node": ">=16"

readme.md

@@ -116,4 +116,5 @@ <div align="center">
 - [`UnknownRecord`](source/unknown-record.d.ts) - Represents an object with `unknown` value. You probably want this instead of `{}`.
+- [`UnknownArray`](source/unknown-array.d.ts) - Represents an array with `unknown` value.
 - [`Except`](source/except.d.ts) - Create a type from an object type without certain keys. This is a stricter version of [`Omit`](https://www.typescriptlang.org/docs/handbook/utility-types.html#omittype-keys).
-- [`Writable`](source/writable.d.ts) - Create a type that strips `readonly` from all or some of an object's keys. The inverse of `Readonly<T>`.
+- [`Writable`](source/writable.d.ts) - Create a type that strips `readonly` from the given type. Inverse of `Readonly<T>`.
 - [`WritableDeep`](source/writable-deep.d.ts) - Create a deeply mutable version of an `object`/`ReadonlyMap`/`ReadonlySet`/`ReadonlyArray` type. The inverse of `ReadonlyDeep<T>`. Use `Writable<T>` if you only need one level deep.
@@ -129,2 +130,3 @@ - [`Merge`](source/merge.d.ts) - Merge two types into a new type. Keys of the second type overrides keys of the first type.
 - [`RequiredDeep`](source/required-deep.d.ts) - Create a deeply required version of another type. Use [`Required<T>`](https://www.typescriptlang.org/docs/handbook/utility-types.html#requiredtype) if you only need one level deep.
+- [`PickDeep`](source/pick-deep.d.ts) - Pick properties from a deeply-nested object. Use [`Pick<T>`](https://www.typescriptlang.org/docs/handbook/utility-types.html#picktype-keys) if you only need one level deep.
 - [`OmitIndexSignature`](source/omit-index-signature.d.ts) - Omit any index signatures from the given object type, leaving only explicitly defined properties.
@@ -180,2 +182,4 @@ - [`PickIndexSignature`](source/pick-index-signature.d.ts) - Pick only index signatures from the given object type, leaving out all explicitly defined properties.
 - [`ArrayValues`](source/array-values.d.ts) - Provides all values for a constant array or tuple.
+- [`SetFieldType`](source/set-field-type.d.ts) - Create a type that changes the type of the given keys.
+- [`Paths`](source/paths.d.ts) - Generate a union of all possible paths to properties in the given object.
 
@@ -182,0 +186,0 @@ ### Type Guard

source/conditional-pick-deep.d.ts

 import type {IsEqual} from './is-equal';
 import type {ConditionalExcept} from './conditional-except';
 import type {ConditionalSimplifyDeep} from './conditional-simplify';
+import type {UnknownRecord} from './unknown-record';
+import type {EmptyObject} from './empty-object';
 
@@ -98,5 +100,5 @@ /**
 		? Type[Key]
-		: Type[Key] extends object
+		: Type[Key] extends UnknownRecord
 			? ConditionalPickDeep<Type[Key], Condition, Options>
 			: typeof conditionalPickDeepSymbol;
-}, (typeof conditionalPickDeepSymbol | undefined) | Record<PropertyKey, never>>>;
+}, (typeof conditionalPickDeepSymbol | undefined) | EmptyObject>, never, UnknownRecord>;

source/internal.d.ts

@@ -5,2 +5,3 @@ import type {Primitive} from './primitive';
 import type {IsAny} from './is-any';
+import type {UnknownRecord} from './unknown-record';
 
@@ -29,2 +30,33 @@ // TODO: Remove for v5.
 /**
+Create an object type with the given key `<Key>` and value `<Value>`.
+
+It will copy the prefix and optional status of the same key from the given object `CopiedFrom` into the result.
+
+@example
+```
+type A = BuildObject<'a', string>;
+//=> {a: string}
+
+// Copy `readonly` and `?` from the key `a` of `{readonly a?: any}`
+type B = BuildObject<'a', string, {readonly a?: any}>;
+//=> {readonly a?: string}
+```
+*/
+export type BuildObject<Key extends PropertyKey, Value, CopiedFrom extends UnknownRecord = {}> =
+	Key extends keyof CopiedFrom
+		? Pick<{[_ in keyof CopiedFrom]: Value}, Key>
+		: Key extends `${infer NumberKey extends number}`
+			? NumberKey extends keyof CopiedFrom
+				? Pick<{[_ in keyof CopiedFrom]: Value}, NumberKey>
+				: {[_ in Key]: Value}
+			: {[_ in Key]: Value};
+
+/**
+Return a string representation of the given string or number.
+
+Note: This type is not the return type of the `.toString()` function.
+*/
+export type ToString<T> = T extends string | number ? `${T}` : never;
+
+/**
 Create a tuple of length `A` and a tuple composed of two other tuples,
@@ -31,0 +63,0 @@ the inferred tuple `U` and a tuple of length `B`, then extracts the length of tuple `U`.

source/partial-deep.d.ts

@@ -1,2 +0,2 @@
-import type {BuiltIns} from './internal';
+import type {BuiltIns, UnknownRecord} from './internal';
 
@@ -72,4 +72,5 @@ /**
 					? PartialReadonlySetDeep<ItemType, Options>
-					: T extends object
-						? T extends ReadonlyArray<infer ItemType> // Test for arrays/tuples, per https://github.com/microsoft/TypeScript/issues/35156
+					: T extends UnknownRecord
+						? PartialObjectDeep<T, Options>
+						: T extends ReadonlyArray<infer ItemType> // Test for arrays/tuples, per https://github.com/microsoft/TypeScript/issues/35156
 							? Options['recurseIntoArrays'] extends true
@@ -82,4 +83,3 @@ ? ItemType[] extends T // Test for arrays (non-tuples) specifically
 								: T // If they don't opt into array testing, just use the original type
-							: PartialObjectDeep<T, Options>
-						: unknown;
+							: T;
 
@@ -86,0 +86,0 @@ /**

source/writable.d.ts

@@ -5,4 +5,18 @@ import type {Except} from './except';
 /**
-Create a type that strips `readonly` from all or some of an object's keys. Inverse of `Readonly<T>`.
+Create a writable version of the given array type.
+*/
+type WritableArray<ArrayType extends readonly unknown[]> =
+	ArrayType extends readonly [] ? []
+		: ArrayType extends readonly [...infer U, infer V] ? [...U, V]
+			: ArrayType extends readonly [infer U, ...infer V] ? [U, ...V]
+				: ArrayType extends ReadonlyArray<infer U> ? U[]
+					: ArrayType;
 
+/**
+Create a type that strips `readonly` from the given type. Inverse of `Readonly<T>`.
+
+The 2nd argument will be ignored if the input type is not an object.
+
+Note: This type can make readonly `Set` and `Map` writable. This behavior is different from `Readonly<T>` (as of TypeScript 5.2.2). See: https://github.com/microsoft/TypeScript/issues/29655
+
 This can be used to [store and mutate options within a class](https://github.com/sindresorhus/pageres/blob/4a5d05fca19a5fbd2f53842cbf3eb7b1b63bddd2/source/index.ts#L72), [edit `readonly` objects within tests](https://stackoverflow.com/questions/50703834), [construct a `readonly` object within a function](https://github.com/Microsoft/TypeScript/issues/24509), or to define a single model where the only thing that changes is whether or not some of the keys are writable.
@@ -31,2 +45,8 @@
 // }
+
+// Also supports array
+const readonlyArray: readonly number[] = [1, 2, 3];
+readonlyArray.push(4); // Will fail as the array itself is readonly.
+const writableArray: Writable<typeof readonlyArray> = readonlyArray as Writable<typeof readonlyArray>;
+writableArray.push(4); // Will work as the array itself is now writable.
 ```
@@ -37,7 +57,15 @@
 export type Writable<BaseType, Keys extends keyof BaseType = keyof BaseType> =
-	Simplify<
-	// Pick just the keys that are not writable from the base type.
-	Except<BaseType, Keys> &
-	// Pick the keys that should be writable from the base type and make them writable by removing the `readonly` modifier from the key.
-	{-readonly [KeyType in keyof Pick<BaseType, Keys>]: Pick<BaseType, Keys>[KeyType]}
-	>;
+BaseType extends ReadonlyMap<infer KeyType, infer ValueType>
+	? Map<KeyType, ValueType>
+	: BaseType extends ReadonlySet<infer ItemType>
+		? Set<ItemType>
+		: BaseType extends readonly unknown[]
+			// Handle array
+			? WritableArray<BaseType>
+			// Handle object
+			: Simplify<
+			// Pick just the keys that are not writable from the base type.
+			Except<BaseType, Keys> &
+			// Pick the keys that should be writable from the base type and make them writable by removing the `readonly` modifier from the key.
+			{-readonly [KeyType in keyof Pick<BaseType, Keys>]: Pick<BaseType, Keys>[KeyType]}
+			>;

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Contains long string literals, which may be a sign of obfuscated or packed code.

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URL strings

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Package contains fragments of external URLs or IP addresses, which the package may be accessing at runtime.

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Fixed alerts

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Long strings

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Contains long string literals, which may be a sign of obfuscated or packed code.

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URL strings

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Package contains fragments of external URLs or IP addresses, which the package may be accessing at runtime.

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Improved metrics

Total package byte prevSize

307774

3.84%

Number of package files

120

3.45%

Lines of code

7186

4.72%

Number of lines in readme file

956

0.42%

Worsened metrics

Number of low supply chain risk alerts

16

6.67%

No dependency changes