Omit<Foo, 'foo'> does more than omitting the 'foo' property

[fabiospampinato]

Bug Report

Omit seems to not work as I'd expect it to, if I do an Omit<Foo, 'foo'> the result is not just that the 'foo' property is omitted from the Foo type.

🔎 Search Terms

• omit in:title

🕗 Version & Regression Information

Reproduces in v5.0.4, not sure about the rest.

⏯ Playground Link

Playground link with relevant code

💻 Code

type Callback = () => void;

type Debounced = Callback & { cancel: Callback, flush: Callback };

type DebouncedNoFlush = Omit<Debounced, 'flush'>;

🙁 Actual behavior

DebouncedNoFlush is no longer a function for some reason.

🙂 Expected behavior

DebouncedNoFlush should still be a function.

[RyanCavanaugh]

See discussion in #53169

[fabiospampinato]

Nice, I didn't search for "homomorphic" unfortunately 😅