azuredatastudio/extensions/json-language-features/server/src/utils/strings.ts

/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the Source EULA. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

export function startsWith(haystack: string, needle: string): boolean {
	if (haystack.length < needle.length) {
		return false;
	}

	for (let i = 0; i < needle.length; i++) {
		if (haystack[i] !== needle[i]) {
			return false;
		}
	}

	return true;
}

/**
 * Determines if haystack ends with needle.
 */
export function endsWith(haystack: string, needle: string): boolean {
	let diff = haystack.length - needle.length;
	if (diff > 0) {
		return haystack.lastIndexOf(needle) === diff;
	} else if (diff === 0) {
		return haystack === needle;
	} else {
		return false;
	}
}

export function convertSimple2RegExpPattern(pattern: string): string {
	return pattern.replace(/[\-\\\{\}\+\?\|\^\$\.\,\[\]\(\)\#\s]/g, '\\$&').replace(/[\*]/g, '.*');
}