azuredatastudio/extensions/markdown-language-features/src/util/hash.ts

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

function numberHash(val: number, initialHashVal: number): number {
	return (((initialHashVal << 5) - initialHashVal) + val) | 0;  // hashVal * 31 + ch, keep as int32
}

export function stringHash(s: string) {
	let hashVal = numberHash(149417, 0);
	for (let i = 0, length = s.length; i < length; i++) {
		hashVal = numberHash(s.charCodeAt(i), hashVal);
	}
	return hashVal;
}