Wrong local variable naming used for setter on generated builder

list prefix {
 key "ip-prefix masklength-range";
 description
 "List of prefix expressions that are part of the set";

 leaf ip-prefix {
 type inet:ip-prefix;
 mandatory true;
 }

 leaf masklength-range {
 type string {
 pattern '([0-9]+\.\.[0-9]+)|exact';
 }
 }
}

private static final Pattern patterns_masklengthrange = Pattern.compile(PATTERN_CONSTANTS_MASKLENGTHRANGE.get(0));

public PrefixBuilder setMasklengthRange(final java.lang.String value) {
if (value != null) {
 check_masklengthRangeLength(value);
 
 CodeHelpers.checkPattern(value, patterns_masklengthRange, regexes_masklengthRange);
}
 this._masklengthRange = value;
 return this;
}

 patterns_masklengthrange != patterns_masklengthRange