@override no longer copies typing information #4275
Description
this seems to be a regression between v20201102 & v20201207. here's an example:
class foo {
/**
* Delete everything in this storage.
*
* @return {!Promise<void>} When clearing has completely.
*/
async clear() {}
}
class fooBar extends foo {
/** @override */
async clear() {
return new Promise((resolve) => {
resolve();
});
}
}in version v20201102 and older, we see no errors:
$ closure-compiler --version
Closure Compiler (http://github.com/google/closure-compiler)
Version: v20201102
$ closure-compiler --jscomp_error='*' --checks-only test.js
but after upgrading to v20201207 (v20250820 behaves the same), we see:
$ closure-compiler --version
Closure Compiler (http://github.com/google/closure-compiler)
Version: v20201207
$ closure-compiler --jscomp_error='*' --checks-only test.js
test.js:12:8: ERROR - [JSC_MISSING_RETURN_JSDOC] Function with non-trivial return must have JSDoc indicating the return type. Please see go/tsjs-problematic-patterns for why @overrides require explicit @return types..
12| async clear() {
^^^^^^^^^
13| return new Promise((resolve) => {
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...
15| });
^^^^^^^
16| }
^^^
1 error(s), 0 warning(s), 94.8% typed
copying the typing info by hand makes it go away, but the documentation says this isn't necessary:
https://github.com/google/closure-compiler/wiki/Annotating-JavaScript-for-the-Closure-Compiler#override
If no other annotations are included, the method or property automatically inherits annotations from its superclass.
i'm guessing this is commit 777ab36 by @rishipal. the associated internal bug suggests this change was made because of a bug in Clutz -- it didn't actually implement the @override semantics. i grok that maybe for internal Google code, since JS->TS was a temporary migration, forcing people to duplicate typing was reasonable, but i don't know why that policy decision was made in the external closure-compiler version.