@difizen/mana-common
Version:
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text/typescript
/*---------------------------------------------------------------------------------------------
* Copyright (c) Microsoft Corporation. All rights reserved.
* Licensed under the MIT License. See License.txt in the project root for license information.
*--------------------------------------------------------------------------------------------*/
import type { URI, UriComponents } from './vscode-uri/uri';
/**
* @returns whether the provided parameter is a JavaScript Array or not.
*/
export function isArray(array: any): array is any[] {
return Array.isArray(array);
}
/**
* @returns whether the provided parameter is a JavaScript String or not.
*/
export function isString(str: unknown): str is string {
return typeof str === 'string';
}
/**
* @returns whether the provided parameter is a JavaScript Array and each element in the array is a string.
*/
export function isStringArray(value: unknown): value is string[] {
return Array.isArray(value) && (<unknown[]>value).every((elem) => isString(elem));
}
/**
*
* @returns whether the provided parameter is of type `object` but **not**
* `null`, an `array`, a `regexp`, nor a `date`.
*/
export function isObject(obj: unknown): obj is Record<any, any> {
// The method can't do a type cast since there are type (like strings) which
// are subclasses of any put not positvely matched by the function. Hence type
// narrowing results in wrong results.
return (
typeof obj === 'object' &&
obj !== null &&
!Array.isArray(obj) &&
!(obj instanceof RegExp) &&
!(obj instanceof Date)
);
}
/**
* In **contrast** to just checking `typeof` this will return `false` for `NaN`.
* @returns whether the provided parameter is a JavaScript Number or not.
*/
export function isNumber(obj: unknown): obj is number {
return typeof obj === 'number' && !isNaN(obj);
}
/**
* @returns whether the provided parameter is a JavaScript Boolean or not.
*/
export function isBoolean(obj: unknown): obj is boolean {
return obj === true || obj === false;
}
/**
* @returns whether the provided parameter is undefined.
*/
export function isUndefined(obj: unknown): obj is undefined {
return typeof obj === 'undefined';
}
/**
* @returns whether the provided parameter is defined.
*/
export function isDefined<T>(arg: T | null | undefined): arg is T {
return !isUndefinedOrNull(arg);
}
/**
* @returns whether the provided parameter is undefined or null.
*/
export function isUndefinedOrNull(obj: unknown): obj is undefined | null {
return isUndefined(obj) || obj === null;
}
export function assertType(condition: unknown, type?: string): asserts condition {
if (!condition) {
throw new Error(type ? `Unexpected type, expected '${type}'` : 'Unexpected type');
}
}
/**
* Asserts that the argument passed in is neither undefined nor null.
*/
export function assertIsDefined<T>(arg: T | null | undefined): T {
if (isUndefinedOrNull(arg)) {
throw new Error('Assertion Failed: argument is undefined or null');
}
return arg;
}
/**
* Asserts that each argument passed in is neither undefined nor null.
*/
export function assertAllDefined<T1, T2>(
t1: T1 | null | undefined,
t2: T2 | null | undefined,
): [T1, T2];
export function assertAllDefined<T1, T2, T3>(
t1: T1 | null | undefined,
t2: T2 | null | undefined,
t3: T3 | null | undefined,
): [T1, T2, T3];
export function assertAllDefined<T1, T2, T3, T4>(
t1: T1 | null | undefined,
t2: T2 | null | undefined,
t3: T3 | null | undefined,
t4: T4 | null | undefined,
): [T1, T2, T3, T4];
export function assertAllDefined(...args: (unknown | null | undefined)[]): unknown[] {
const result = [];
for (let i = 0; i < args.length; i++) {
const arg = args[i];
if (isUndefinedOrNull(arg)) {
throw new Error(`Assertion Failed: argument at index ${i} is undefined or null`);
}
result.push(arg);
}
return result;
}
const { hasOwnProperty } = Object.prototype;
/**
* @returns whether the provided parameter is an empty JavaScript Object or not.
*/
export function isEmptyObject(obj: unknown): obj is object {
if (!isObject(obj)) {
return false;
}
for (const key in obj) {
if (hasOwnProperty.call(obj, key)) {
return false;
}
}
return true;
}
/**
* @returns whether the provided parameter is a JavaScript Function or not.
*/
export function isFunction(obj: unknown): obj is (...args: any[]) => any {
return typeof obj === 'function';
}
/**
* @returns whether the provided parameters is are JavaScript Function or not.
*/
export function areFunctions(...objects: unknown[]): boolean {
return objects.length > 0 && objects.every(isFunction);
}
export type TypeConstraint = string | ((...args: any[]) => any);
export function validateConstraints(
args: unknown[],
constraints: (TypeConstraint | undefined)[],
): void {
const len = Math.min(args.length, constraints.length);
for (let i = 0; i < len; i++) {
validateConstraint(args[i], constraints[i]);
}
}
export function validateConstraint(
arg: unknown,
constraint: TypeConstraint | undefined,
): void {
if (isString(constraint)) {
if (typeof arg !== constraint) {
throw new Error(`argument does not match constraint: typeof ${constraint}`);
}
} else if (isFunction(constraint)) {
try {
if (arg instanceof constraint) {
return;
}
} catch {
// ignore
}
if (!isUndefinedOrNull(arg) && (arg as any).constructor === constraint) {
return;
}
if (constraint.length === 1 && constraint.call(undefined, arg) === true) {
return;
}
throw new Error(
`argument does not match one of these constraints: arg instanceof constraint, arg.constructor === constraint, nor constraint(arg) === true`,
);
}
}
export function getAllPropertyNames(obj: object): string[] {
let res: string[] = [];
let proto = Object.getPrototypeOf(obj);
while (Object.prototype !== proto) {
res = res.concat(Object.getOwnPropertyNames(proto));
proto = Object.getPrototypeOf(proto);
}
return res;
}
export function getAllMethodNames(obj: object): string[] {
const methods: string[] = [];
for (const prop of getAllPropertyNames(obj)) {
if (typeof (obj as any)[prop] === 'function') {
methods.push(prop);
}
}
return methods;
}
export function createProxyObject<T extends object>(
methodNames: string[],
invoke: (method: string, args: unknown[]) => unknown,
): T {
const createProxyMethod = (method: string): (() => unknown) => {
return function () {
// eslint-disable-next-line prefer-rest-params
const args = Array.prototype.slice.call(arguments, 0);
return invoke(method, args);
};
};
const result = {} as T;
for (const methodName of methodNames) {
(<any>result)[methodName] = createProxyMethod(methodName);
}
return result;
}
/**
* Converts null to undefined, passes all other values through.
*/
export function withNullAsUndefined<T>(x: T | null): T | undefined {
return x === null ? undefined : x;
}
/**
* Converts undefined to null, passes all other values through.
*/
export function withUndefinedAsNull<T>(x: T | undefined): T | null {
return typeof x === 'undefined' ? null : x;
}
/**
* Allows to add a first parameter to functions of a type.
*/
export type AddFirstParameterToFunctions<
Target,
TargetFunctionsReturnType,
FirstParameter,
> = {
// For every property
[]: Target[K] extends (...args: any[]) => TargetFunctionsReturnType // Function: add param to function
? (
firstArg: FirstParameter,
...args: Parameters<Target[K]>
) => ReturnType<Target[K]>
: // Else: just leave as is
Target[K];
};
/**
* Mapped-type that replaces all occurrences of URI with UriComponents
*/
export type UriDto<T> = {
[]: T[K] extends URI ? UriComponents : UriDto<T[K]>;
};
/**
* Mapped-type that replaces all occurrences of URI with UriComponents and
* drops all functions.
*/
export type Dto<T> = T extends { toJSON: () => infer U }
? U
: T extends object
? { [k in keyof T]: Dto<T[k]> }
: T;
export function NotImplementedProxy<T>(name: string): { new (): T } {
return <any>class {
constructor() {
return new Proxy(
{},
{
get(target: any, prop: PropertyKey) {
if (target[prop]) {
return target[prop];
}
throw new Error(`Not Implemented: ${name}->${String(prop)}`);
},
},
);
}
};
}