monaco-editor/esm/vs/base/common/types.js

A browser based code editor

import { assert } from './assert.js';

/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/
/**
 * @returns whether the provided parameter is a JavaScript String or not.
 */
function isString(str) {
    return (typeof str === 'string');
}
/**
 * @returns whether the provided parameter is a JavaScript Array and each element in the array satisfies the provided type guard.
 */
function isArrayOf(value, check) {
    return Array.isArray(value) && value.every(check);
}
/**
 * @returns whether the provided parameter is of type `object` but **not**
 *	`null`, an `array`, a `regexp`, nor a `date`.
 */
function isObject(obj) {
    // 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);
}
/**
 * @returns whether the provided parameter is of type `Buffer` or Uint8Array dervived type
 */
function isTypedArray(obj) {
    const TypedArray = Object.getPrototypeOf(Uint8Array);
    return typeof obj === 'object'
        && obj instanceof TypedArray;
}
/**
 * In **contrast** to just checking `typeof` this will return `false` for `NaN`.
 * @returns whether the provided parameter is a JavaScript Number or not.
 */
function isNumber(obj) {
    return (typeof obj === 'number' && !isNaN(obj));
}
/**
 * @returns whether the provided parameter is an Iterable, casting to the given generic
 */
function isIterable(obj) {
    // eslint-disable-next-line local/code-no-any-casts
    return !!obj && typeof obj[Symbol.iterator] === 'function';
}
/**
 * @returns whether the provided parameter is a JavaScript Boolean or not.
 */
function isBoolean(obj) {
    return (obj === true || obj === false);
}
/**
 * @returns whether the provided parameter is undefined.
 */
function isUndefined(obj) {
    return (typeof obj === 'undefined');
}
/**
 * @returns whether the provided parameter is defined.
 */
function isDefined(arg) {
    return !isUndefinedOrNull(arg);
}
/**
 * @returns whether the provided parameter is undefined or null.
 */
function isUndefinedOrNull(obj) {
    return (isUndefined(obj) || obj === null);
}
function assertType(condition, type) {
    if (!condition) {
        throw new Error(type ? `Unexpected type, expected '${type}'` : 'Unexpected type');
    }
}
/**
 * Asserts that the argument passed in is neither undefined nor null.
 *
 * @see {@link assertDefined} for a similar utility that leverages TS assertion functions to narrow down the type of `arg` to be non-nullable.
 */
function assertReturnsDefined(arg) {
    assert(arg !== null && arg !== undefined, 'Argument is `undefined` or `null`.');
    return arg;
}
/**
 * @returns whether the provided parameter is a JavaScript Function or not.
 */
function isFunction(obj) {
    return (typeof obj === 'function');
}
function validateConstraints(args, constraints) {
    const len = Math.min(args.length, constraints.length);
    for (let i = 0; i < len; i++) {
        validateConstraint(args[i], constraints[i]);
    }
}
function validateConstraint(arg, constraint) {
    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
        }
        // eslint-disable-next-line local/code-no-any-casts
        if (!isUndefinedOrNull(arg) && arg.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`);
    }
}
/**
 * Helper type assertion that safely upcasts a type to a supertype.
 *
 * This can be used to make sure the argument correctly conforms to the subtype while still being able to pass it
 * to contexts that expects the supertype.
 */
function upcast(x) {
    return x;
}

export { assertReturnsDefined, assertType, isArrayOf, isBoolean, isDefined, isFunction, isIterable, isNumber, isObject, isString, isTypedArray, isUndefined, isUndefinedOrNull, upcast, validateConstraint, validateConstraints };