@woosh/meep-engine/src/core/path/computeFileExtension.js

Pure JavaScript game engine. Fully featured and production ready.

import { computePathBase } from "./computePathBase.js";

/**
 *
 * @param {string} path
 * @returns {String|null}
 */
export function computeFileExtension(path) {
    const type_of_path = typeof path;
    if (type_of_path !== "string") {
        throw new Error(`path must be a string, instead was '${type_of_path}'`);
    }

    const base = computePathBase(path);

    const lastDotIndex = base.lastIndexOf('.');

    if (lastDotIndex !== -1) {
        return base.substring(lastDotIndex + 1);
    } else {
        //no extension
        return null;
    }
}