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tests/cases/conformance/types/typeRelationships/typeInference/genericCallWithObjectTypeArgsAndConstraints3.ts(18,32): error TS2741: Property 'y' is missing in type 'Derived2' but required in type 'Derived'.
==== tests/cases/conformance/types/typeRelationships/typeInference/genericCallWithObjectTypeArgsAndConstraints3.ts (1 errors) ====
// Generic call with constraints infering type parameter from object member properties
class Base {
x: string;
}
class Derived extends Base {
y: string;
}
class Derived2 extends Base {
z: string;
}
function f<T extends Base>(a: { x: T; y: T }) {
var r: T;
return r;
}
var r1 = f({ x: new Derived(), y: new Derived2() }); // error because neither is supertype of the other
~
!!! error TS2741: Property 'y' is missing in type 'Derived2' but required in type 'Derived'.
!!! related TS2728 tests/cases/conformance/types/typeRelationships/typeInference/genericCallWithObjectTypeArgsAndConstraints3.ts:7:5: 'y' is declared here.
!!! related TS6500 tests/cases/conformance/types/typeRelationships/typeInference/genericCallWithObjectTypeArgsAndConstraints3.ts:13:39: The expected type comes from property 'y' which is declared here on type '{ x: Derived; y: Derived; }'
function f2<T extends Base, U extends { x: T; y: T }>(a: U) {
var r: T;
return r;
}
var r2 = f2({ x: new Derived(), y: new Derived2() }); // ok
var r3 = f2({ x: new Derived(), y: new Derived2() }); // ok
function f3<T extends Base>(y: (a: T) => T, x: T) {
return y(null);
}
// all ok - second argument is processed before x is fixed
var r4 = f3(x => x, new Base());
var r5 = f3(x => x, new Derived());
var r6 = f3(x => x, null);
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