Closed
Description
Repro
npm install @types/react
index.ts
type Stuff<T> =
T extends keyof JSX.IntrinsicElements
? JSX.IntrinsicElements[T]
: any;
function F<T, U>(p1: Stuff<T>, p2: Stuff<U>) {
p1 = p2; // Error
}tsc index.ts --noEmit --skipLibCheck --extendedDiagnostifcs
Effect
Check time increased from ~0.5s in b2d1f53 to ~7.0s in 2643e65 (aka #30639).
Repro is reduced from a variance check of React's ComponentProps.