==== tests/cases/compiler/interfaceImplementation7.ts (2 errors) ====
    interface i1{ name(): { s: string; }; }
    interface i2{ name(): { n: number; }; }
    
    interface i3 extends i1, i2 { }
              ~~
!!! interfaceImplementation7.ts(4,11): error TS2189: Interface 'i3' cannot simultaneously extend types 'i1' and 'i2':
!!! Named properties 'name' of types 'i1' and 'i2' are not identical.
    interface i4 extends i1, i2 { name(): { s: string; n: number; }; }
    
    class C1 implements i4 {
          ~~
!!! interfaceImplementation7.ts(7,7): error TS2137: Class C1 declares interface i4 but does not implement it:
!!! 	Types of property 'name' of types 'C1' and 'i4' are incompatible:
!!! 		Call signatures of types '() => string' and '() => { s: string; n: number; }' are incompatible:
!!! 			Type 'String' is missing property 's' from type '{ s: string; n: number; }'.
        public name(): string { return ""; }
    }
    