From 16435d510b42b946df70b25e19cb73c4c5ef220d Mon Sep 17 00:00:00 2001 From: Sindre Sorhus Date: Sat, 2 Feb 2019 21:42:53 +0700 Subject: [PATCH] More improvements --- source/index.ts | 42 +++++++++++++++++++++++------------------- 1 file changed, 23 insertions(+), 19 deletions(-) diff --git a/source/index.ts b/source/index.ts index f54d10a..60a29a2 100644 --- a/source/index.ts +++ b/source/index.ts @@ -7,20 +7,8 @@ // tslint:disable-next-line const URLGlobal = typeof URL === 'undefined' ? require('url').URL : URL; -type TypedArray = Int8Array | Uint8Array | Uint8ClampedArray | Int16Array | Uint16Array | Int32Array | Uint32Array | Float32Array | Float64Array; - -// TODO: This should be able to be `not object` when the `not` operator is out -type Primitive = null | undefined | string | number | boolean | symbol; - -export interface ArrayLike { - length: number; -} - export type Class = new(...args: any[]) => T; -type DomElement = object & {nodeType: 1; nodeName: string}; -type NodeStream = object & {pipe: Function}; - export const enum TypeName { null = 'null', boolean = 'boolean', @@ -202,9 +190,9 @@ is.urlString = (value: unknown): value is string => { }; // TODO: Use the `not` operator with a type guard here when it's available. -// Example: `is.truthy = (value: unknown): value is not (false | undefined | null) => Boolean(value);` +// Example: `is.truthy = (value: unknown): value is (not false | not 0 | not '' | not undefined | not null) => Boolean(value);` is.truthy = (value: unknown) => Boolean(value); -// Example: `is.falsy = (value: unknown): value is not (true | …) => Boolean(value);` +// Example: `is.falsy = (value: unknown): value is (not true | 0 | '' | undefined | null) => Boolean(value);` is.falsy = (value: unknown) => !value; is.nan = (value: unknown) => Number.isNaN(value as number); @@ -217,6 +205,9 @@ const primitiveTypeOfTypes = new Set([ 'symbol' ]); +// TODO: This should be able to be `not object` when the `not` operator is out +export type Primitive = null | undefined | string | number | boolean | symbol; + is.primitive = (value: unknown): value is Primitive => is.null_(value) || primitiveTypeOfTypes.has(typeof value); is.integer = (value: unknown): value is number => Number.isInteger(value as number); @@ -243,6 +234,8 @@ const typedArrayTypes = new Set([ TypeName.Float64Array ]); +export type TypedArray = Int8Array | Uint8Array | Uint8ClampedArray | Int16Array | Uint16Array | Int32Array | Uint32Array | Float32Array | Float64Array; + is.typedArray = (value: unknown): value is TypedArray => { const objectType = getObjectType(value); if (objectType === null) { @@ -252,8 +245,13 @@ is.typedArray = (value: unknown): value is TypedArray => { return typedArrayTypes.has(objectType); }; +export interface ArrayLike { + readonly length: number; + readonly [index: number]: T; +} + const isValidLength = (value: unknown) => is.safeInteger(value) && value >= 0; -is.arrayLike = (value: unknown): value is ArrayLike => !is.nullOrUndefined(value) && !is.function_(value) && isValidLength((value as ArrayLike).length); +is.arrayLike = (value: unknown): value is ArrayLike => !is.nullOrUndefined(value) && !is.function_(value) && isValidLength((value as ArrayLike).length); is.inRange = (value: number, range: number | number[]): value is number => { if (is.number(range)) { @@ -276,8 +274,8 @@ const DOM_PROPERTIES_TO_CHECK = [ 'nodeValue' ]; -is.domElement = (value: unknown): value is DomElement => is.object(value) && (value as DomElement).nodeType === NODE_TYPE_ELEMENT && is.string((value as DomElement).nodeName) && - !is.plainObject(value) && DOM_PROPERTIES_TO_CHECK.every(property => property in (value as DomElement)); +is.domElement = (value: unknown): value is Element => is.object(value) && (value as Element).nodeType === NODE_TYPE_ELEMENT && is.string((value as Element).nodeName) && + !is.plainObject(value) && DOM_PROPERTIES_TO_CHECK.every(property => property in (value as Element)); export interface ObservableLike { subscribe(observer: (value: unknown) => void): void; @@ -300,9 +298,11 @@ is.observable = (value: unknown): value is ObservableLike => { return false; }; +export type NodeStream = object & {readonly pipe: Function}; + is.nodeStream = (value: unknown): value is NodeStream => !is.nullOrUndefined(value) && isObject(value) as unknown && is.function_((value as NodeStream).pipe) && !is.observable(value); -is.infinite = (value: unknown) => value === Infinity || value === -Infinity; +is.infinite = (value: unknown): value is number => value === Infinity || value === -Infinity; const isAbsoluteMod2 = (rem: number) => (value: number): value is number => is.integer(value) && Math.abs(value % 2) === rem; is.evenInteger = isAbsoluteMod2(0); @@ -311,7 +311,9 @@ is.oddInteger = isAbsoluteMod2(1); is.emptyArray = (value: unknown): value is never[] => is.array(value) && value.length === 0; is.nonEmptyArray = (value: unknown): value is unknown[] => is.array(value) && value.length > 0; -is.emptyString = (value: unknown): value is string => is.string(value) && value.length === 0; +is.emptyString = (value: unknown): value is '' => is.string(value) && value.length === 0; + +// TODO: Use `not ''` when the `not` operator is available. is.nonEmptyString = (value: unknown): value is string => is.string(value) && value.length > 0; const isWhiteSpaceString = (value: unknown) => is.string(value) && /\S/.test(value) === false; @@ -330,7 +332,9 @@ is.emptyMap = (value: unknown): value is Map => is.map(value) && v is.nonEmptyMap = (value: unknown): value is Map => is.map(value) && value.size > 0; export type Predicate = (value: unknown) => boolean; + type ArrayMethod = (fn: (value: unknown, index: number, array: unknown[]) => boolean, thisArg?: unknown) => boolean; + const predicateOnArray = (method: ArrayMethod, predicate: Predicate, values: unknown[]) => { if (is.function_(predicate) === false) { throw new TypeError(`Invalid predicate: ${JSON.stringify(predicate)}`);