Test to repro crash

tests/cases/compiler/getSignatureOfTypeCrash.ts

@@ -0,0 +1,17 @@
+declare interface Foo {
+    a(): boolean;
+    b(): void;
+    c(argument: boolean): void;
+    d(argument: number): void;
+}
+
+declare const Foo: Mapped<Foo>;
+type Mapped<T> = {
+  [K in keyof T]: T[K] extends (...args: infer Args) => infer R
+    ? (...args: Args) => R
+    : never;
+};
+
+function foo(key: 'a' | 'b' | 'c' | 'd') {
+  Foo[key]();
+}