tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypingWithObjectMembers.ts(12,7): error TS2415: Class 'B' incorrectly extends base class 'A'. Types of property 'bar' are incompatible. Type 'string' is not assignable to type 'Base'. Property 'foo' is missing in type 'String'. tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypingWithObjectMembers.ts(22,7): error TS2415: Class 'B2' incorrectly extends base class 'A2'. Types of property '2.0' are incompatible. Type 'string' is not assignable to type 'Base'. tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypingWithObjectMembers.ts(32,7): error TS2415: Class 'B3' incorrectly extends base class 'A3'. Types of property ''2.0'' are incompatible. Type 'string' is not assignable to type 'Base'. tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypingWithObjectMembers.ts(43,11): error TS2415: Class 'B' incorrectly extends base class 'A'. Types of property 'bar' are incompatible. Type 'string' is not assignable to type 'Base'. tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypingWithObjectMembers.ts(53,11): error TS2415: Class 'B2' incorrectly extends base class 'A2'. Types of property '2.0' are incompatible. Type 'string' is not assignable to type 'Base'. tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypingWithObjectMembers.ts(63,11): error TS2415: Class 'B3' incorrectly extends base class 'A3'. Types of property ''2.0'' are incompatible. Type 'string' is not assignable to type 'Base'. ==== tests/cases/conformance/types/typeRelationships/subtypesAndSuperTypes/subtypingWithObjectMembers.ts (6 errors) ==== class Base { foo: string; } class Derived extends Base { bar: string; } class Derived2 extends Derived { baz: string; } // N and M have the same name, same accessibility, same optionality, and N is a subtype of M // foo properties are valid, bar properties cause errors in the derived class declarations class A { foo: Base; bar: Base; } class B extends A { ~ !!! error TS2415: Class 'B' incorrectly extends base class 'A'. !!! error TS2415: Types of property 'bar' are incompatible. !!! error TS2415: Type 'string' is not assignable to type 'Base'. !!! error TS2415: Property 'foo' is missing in type 'String'. foo: Derived; // ok bar: string; // error } class A2 { 1: Base; 2.0: Base; } class B2 extends A2 { ~~ !!! error TS2415: Class 'B2' incorrectly extends base class 'A2'. !!! error TS2415: Types of property '2.0' are incompatible. !!! error TS2415: Type 'string' is not assignable to type 'Base'. 1: Derived; // ok 2: string; // error } class A3 { '1': Base; '2.0': Base; } class B3 extends A3 { ~~ !!! error TS2415: Class 'B3' incorrectly extends base class 'A3'. !!! error TS2415: Types of property ''2.0'' are incompatible. !!! error TS2415: Type 'string' is not assignable to type 'Base'. '1': Derived; // ok '2.0': string; // error } module TwoLevels { class A { foo: Base; bar: Base; } class B extends A { ~ !!! error TS2415: Class 'B' incorrectly extends base class 'A'. !!! error TS2415: Types of property 'bar' are incompatible. !!! error TS2415: Type 'string' is not assignable to type 'Base'. foo: Derived2; // ok bar: string; // error } class A2 { 1: Base; 2.0: Base; } class B2 extends A2 { ~~ !!! error TS2415: Class 'B2' incorrectly extends base class 'A2'. !!! error TS2415: Types of property '2.0' are incompatible. !!! error TS2415: Type 'string' is not assignable to type 'Base'. 1: Derived2; // ok 2: string; // error } class A3 { '1': Base; '2.0': Base; } class B3 extends A3 { ~~ !!! error TS2415: Class 'B3' incorrectly extends base class 'A3'. !!! error TS2415: Types of property ''2.0'' are incompatible. !!! error TS2415: Type 'string' is not assignable to type 'Base'. '1': Derived2; // ok '2.0': string; // error } }