Add tests

tests/cases/conformance/types/rest/restTuplesFromContextualTypes.ts

@@ -59,6 +59,21 @@ function f4<T extends any[]>(t: T) {
     f((a, b, ...x) => {});
 }
 
+declare function f5<T extends any[], U>(f: (...args: T) => U): (...args: T) => U;
+
+let g0 = f5(() => "hello");
+let g1 = f5((x, y) => 42);
+let g2 = f5((x: number, y) => 42);
+let g3 = f5((x: number, y: number) => x + y);
+let g4 = f5((...args) => true);
+
+declare function pipe<A extends any[], B, C>(f: (...args: A) => B, g: (x: B) => C): (...args: A) => C;
+
+let g5 = pipe(() => true, b => 42);
+let g6 = pipe(x => "hello", s => s.length);
+let g7 = pipe((x, y) => 42, x => "" + x);
+let g8 = pipe((x: number, y: string) => 42, x => "" + x);
+
 // Repro from #25288
 
 declare var tuple: [number, string];