JSDoc comments get added to @license block

[alexeagle]

This file just exports a function:
https://github.com/angular/angular/blob/master/modules/@angular/core/src/util/lang.ts

Tsickle inserts the JSDoc for this function into the same comment with a @license tag, which is implicitly file-level:

/**
 * @license
 * Copyright Google Inc. All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 * @param {?} obj
 * @return {?}
 */
export function isPromise(obj) {
    // allow any Promise/A+ compliant thenable.
    // It's up to the caller to ensure that obj.then conforms to the spec
    return !!obj && typeof obj.then === 'function';
}
//# sourceMappingURL=lang.js.map

Hilariously, closure treats this @license comment as being a different license from the rest of angular, so an extra copy of the license ends up in the closure-compiled bundle:
https://github.com/alexeagle/closure-compiler-angular-bundling/blob/9feee26fad39501004759711bdf474944187f105/dist/bundle.js#L68

And that probably costs us a handful of extra bytes in the minified app.

[evmar]

Haha that is hilarious!

Syntactically the comment in that file is the jsdoc for the function. If you paste that file into the playground then write "isPromise" you'll see that @license comment shows up in the hover text in the function documentation. That means it probably also shows up in the d.ts (?). So I think the fix is to add a /** */ just before the function to show that it's undocumented.

[mprobst]

We could also detect that there's a @fileoverview or @license in the `/** */` comment, and in that case create a secondary comment.