==== tests/cases/compiler/stringIndexerAssignments1.ts (2 errors) ====
    var x: { [index: string]: string; one: string; };
    var a: { one: string; };
    var b: { one: number; two: string; };
    x = a;
    ~
!!! Type '{ one: string; }' is not assignable to type '{ [x: string]: string; one: string; }':
!!!   Index signature is missing in type '{ one: string; }'.
    x = b; // error
    ~
!!! Type '{ one: number; two: string; }' is not assignable to type '{ [x: string]: string; one: string; }':
!!!   Types of property 'one' are incompatible:
!!!     Type 'number' is not assignable to type 'string'.