Constants should be declared as regular variables or static class properties, using all uppercase letters.
Node.js / V8 supports mozilla's const extension, but unfortunately that cannot be applied to class members, nor is it part of any ECMA standard.
Right:
var SECOND = 1 * 1000;
function File() {
}
File.FULL_PERMISSIONS = 0777;Wrong:
const SECOND = 1 * 1000;
function File() {
}
File.fullPermissions = 0777;