instanceof returns True in cases where the requested class is not accessible

[davidnich]

instanceof should return False for privately-inherited base classes when the requested class is not accessible; in such cases the API requested with instanceof is not actually available

[omusil24]

Current status:

#!/usr/bin/env qore
# -*- mode: qore; indent-tabs-mode: nil -*-

%new-style
%enable-all-warnings
%require-types
%strict-args

%requires QUnit

%exec-class QUnitTest

class A inherits public X {
    constructor() : X() {}
}

class B inherits private X {
    constructor() : X() {}
}

class C inherits private:internal X {
    constructor() : X() {}
}

class X {
}

public class QUnitTest inherits QUnit::Test {
    constructor() : Test("QUnitTest", "1.0") {
        addTestCase("test", \testMethod(), NOTHING);

        # Return for compatibility with test harness that checks return value.
        set_return_value(main());
    }

    testMethod() {
        A a();
        B b();
        C c();

        assertTrue(a instanceof A);
        assertTrue(b instanceof B);
        assertTrue(c instanceof C);

        # OK
        assertTrue(a instanceof X);

        # prints INVALID-OPERATION: 'object<B> instanceof object<X>' always returns False
        assertFalse(b instanceof X);

        # prints INVALID-OPERATION: 'object<C> instanceof object<X>' always returns False
        assertFalse(c instanceof X); # prints INVALID-OPERATION warning
    }
}

Therefore I'd say this bug is fixed.