/**
* Copyright 2017 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
// We are doing some heavy reflective stuff, lots of any casting necessary
/* tslint:disable:no-any */
import { Code, FirestoreError } from './error';
/**
* Helper function to prevent instantiation through the constructor.
*
* This method creates a new constructor that throws when it's invoked.
* The prototype of that constructor is then set to the prototype of the hidden
* "class" to expose all the prototype methods and allow for instanceof
* checks.
*
* To also make all the static methods available, all properties of the
* original constructor are copied to the new constructor.
*/
export function makeConstructorPrivate<T>(cls: T, optionalMessage?: string): T {
function PublicConstructor() {
let error = 'This constructor is private.';
if (optionalMessage) {
error += ' ';
error += optionalMessage;
}
throw new FirestoreError(Code.INVALID_ARGUMENT, error);
}
// Make sure instanceof checks work and all methods are exposed on the public
// constructor
PublicConstructor.prototype = (cls as any).prototype;
// Copy any static methods/members
for (const staticProperty in cls) {
Eif (cls.hasOwnProperty(staticProperty)) {
(PublicConstructor as any)[staticProperty] = (cls as any)[staticProperty];
}
}
return PublicConstructor as any;
}
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