/**

* Copyright (c) Facebook, Inc. and its affiliates.

*

* This source code is licensed under the MIT license found in the

* LICENSE file in the root directory of this source tree.

*/

/** Adds a given string prefix to `str`. */

export function addPrefix(str: string, prefix: string): string {

return str.startsWith(prefix) ? str : `${prefix}${str}`;

}

/** Removes a given string suffix from `str`. */

export function removeSuffix(str: string, suffix: string): string {

if (suffix === '') {

// str.slice(0, 0) is ""

return str;

}

return str.endsWith(suffix) ? str.slice(0, -suffix.length) : str;

}

/** Adds a given string suffix to `str`. */

export function addSuffix(str: string, suffix: string): string {

return str.endsWith(suffix) ? str : `${str}${suffix}`;

}

/** Removes a given string prefix from `str`. */

export function removePrefix(str: string, prefix: string): string {

return str.startsWith(prefix) ? str.slice(prefix.length) : str;

}