interface I1 {}
interface I2 : I1 {}
class A : I2 {}
auto interfaces = interfaceGraph (A.classinfo);
// interfaces = [I1.classinfo, I2.classinfo]
interface I1 {}
interface I2 {}
class A : I1 {}
class B : A, I2 {}
auto interfaces = interfaceGraph (B.classinfo);
// interfaces = [I2.classinfo]