Open steveluscher opened 1 month ago
Shorter repro
declare function type<T>(): T;
interface KeyCaller<T> {
callMe<K extends keyof T>(arg: K, val: T[K]): void;
}
interface KeyCaller2<T> extends KeyCaller<T> { }
type Foo = { foo: string };
type Bar = { bar: number };
// Error, good
type<KeyCaller<Foo>>() satisfies KeyCaller<Bar>;
// No error, bad
type<KeyCaller<Foo>>() satisfies KeyCaller2<Bar>;
🔎 Search Terms
interface interface constrain extend interface
🕗 Version & Regression Information
⏯ Playground Link
https://www.typescriptlang.org/play/?#code/PQKhAIGUFEBUFUAK4C8b0c1z4TAFABmArgHYDGALgJYD2p4lAngA4CmAPLAHwAUAlAC5wscAG9wAJzaVikhqWIAbJeACGAZ3BkA1qVoB3BppEBucAF98zduGgA3NqUoBZNS1TgASm3K1JACYcGpSS1KQA5gA0do7O3KbWrGzgADLUIU5sklwOTpTgbAAelE4BWnnxnry8bPaUwrCVlPyo3OD2tNQBrQA+4uAAFmqkAUpszby0AEYAVr4NIs1CHV0Blon4xSz+BeGlkoRq5CmwyQHN0AC21JQHuXGu7oUlZRWPbiztYvjgf+oBC6PdKZUjZB75M62YqlUZaHRsJi0QhLD7uPi-f5YmxsRrNKFsKKYrF-JQZWHZYQgik5JpolgAbTpkOSAF1uESSf9aCwaPQNAB+YQAQUBzWpWUkAHleXRSFp+tNaLRxiNOf8Vp1uoksdIrrRHOLyZKIc4CS9YeVwAikSjmc5PhiuX8cXjHgT1VyyaDKWljWDac1Pkz8WyOcSSTy+fKhbF8hKAzLowrwEqVWw1RHNWtElZQBBoAA5AAiUDgSFQ2Cr1ZQuAI+HzvwggFByKAjW5MRhsEJNgg4rjnS43O7giSEZXCZqWbh8VoaNQ0DSEajdkSDx7XW73McTuPOafmYDAcDN-AN48AAUoGgAtNsFnfJJJ-El2AP2ED8puRzkJNM1JIk6PNOs7gPOi7LquBKfs437buA460EB+QHuAR4nmeja4Ce4DCmSJjIowgwpP41AROEaiqDivavikADCypKEOW7gvaTweDCbx7ux7S1tBzE-qaPGbP2DEqgJ8GIch+4WDOAhgQuGSQVo-EbsOkm7lOsmHsep4Rs6BmGUZxkmaZJnoVet73lQj7PpItEcGJTFqSxv6pgB0kFLJoHgUpK4qeuX7qaOCGacB2lobpmFgE24CADLk4AAJLONkRwnERC5gdQVwsEonacXCREkWE5GkJRjDJDR+ypcc9GMclBxpRMLmCWxnwWlxQboh1hWqUFrlCY6AxWA5TkNTVJwSSFUncSB8m+Uu-lrh+U1uTNWkJJFGH6WZu17ftB1GRZ153kU7A2dkdmjfVKWHLVq0cH+Hmzd582KYtUGBbBwVrWFKERehcXRSAsUJeNd3pZQwwFAVVpQ8VZEUVRyTqKMAJWiExCEIQVW3U14BjXjtWIEoxAaMWGQsAu5CDA9bXPLD7z5ENjPLWwMGUHBrFdV84gRgElPU7TjxCearM2oR9NfLU9husz7ghu6bLZtq+AjaJN2NcTpPk4LlA0w9O5IS9clzu9ylsxzXO-cbG06dth2O07zsu38x1WWdD6XS+GsquDTUk2TFMaFT+vC-1glPYBJs+ebS19d9A1G55qGA8DsWtgxLCdlTIThBERXgH4AQpOEmRqOshGw-nhfVRDKQGP4OgaLjWvpVnTCIJopRWz9g0M68hU898EYVxzCbc0r0KD1aEt2sPvA7S6yRy2aySeiS3o0lS-qT-LjJsQS7Ib1iUZyoKIpisCu-SrK-LgIqjEZqQG8qwEOr-HqBrNfGN+iyj4tESSwXkvCq7BV6UA9KArekod4+kDPSRWLJ2DH1AWffksYjTwKTOfB+qYn6ZixG-D+fwBYhyFs0f+09LTwiAfPekfA6gQODIfZWwgtTvzVmeDW2cu6ZF7knUKttwqmwUhBeOX1OZ92Tibe2elXYKMUftd2p1zqUFsj7ZIjkeSd27uzQ27lo4bVjuIz6K0WoaWEf9Ta6FmxAA
💻 Code
🙁 Actual behavior
As soon as the original interface is extended – whether the extender adds properties, does not add properties, uses the type parameter, or doesn't use the type parameter – I seem to lose the ability to constrain types in the same way as the original interface can.
🙂 Expected behavior
I would expect an interface that extends another to constrain types in exactly the same way as the original.
Additional information about the issue
No response