Nodejs Utililty Methods String Trimming Right

String.prototype.TrimEnd = function (v)
    if (this.substring(this.length - 1, this.length) == v) {
        return this.substring(0, this.length - 1);
    else {
        return this;

String.prototype.RTrim = function() {
    return this.replace(/\s+$/g, "");

String.prototype.Rtrim = function(){
  return this.replace(/(\s*$)/g, "");
};

String.prototype.endTrim = function (char) {
    let length = this.length;
    if (length) {
        if (this.charAt(length - 1) === char) {
            return this.substring(0, length - 1);
    return this.toString();
};
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