=== tests/cases/compiler/classImplementingInterfaceIndexer.ts ===
interface I {
>I : Symbol(I, Decl(classImplementingInterfaceIndexer.ts, 0, 0))

    [index: string]: { prop }
>index : Symbol(index, Decl(classImplementingInterfaceIndexer.ts, 1, 5))
>prop : Symbol(prop, Decl(classImplementingInterfaceIndexer.ts, 1, 22))
}
class A implements I {
>A : Symbol(A, Decl(classImplementingInterfaceIndexer.ts, 2, 1))
>I : Symbol(I, Decl(classImplementingInterfaceIndexer.ts, 0, 0))

    [index: string]: { prop }
>index : Symbol(index, Decl(classImplementingInterfaceIndexer.ts, 4, 5))
>prop : Symbol(prop, Decl(classImplementingInterfaceIndexer.ts, 4, 22))
}