import org.checkerframework.checker.interning.qual.Interned;
import org.checkerframework.checker.interning.qual.InternedDistinct;

public class Distinct {

    class Foo {}

    Foo f1;
    Foo f2;
    @Interned Foo i1;
    @Interned Foo i2;
    @InternedDistinct Foo d1;
    @InternedDistinct Foo d2;

    public void testEquals() {
        // :: error: not.interned
        if (f1 == f2) {}
        // :: error: not.interned
        if (f1 == i2) {}
        if (f1 == d2) {}
        // :: error: not.interned
        if (i1 == f2) {}
        if (i1 == i2) {}
        if (i1 == d2) {}
        if (d1 == f2) {}
        if (d1 == i2) {}
        if (d1 == d2) {}
    }

    public void testAssignment1() {
        f1 = f2;
    }

    public void testAssignment2() {
        f1 = i2;
    }

    public void testAssignment3() {
        f1 = d2;
    }

    public void testAssignment4() {
        // :: error: assignment.type.incompatible
        i1 = f2;
    }

    public void testAssignment5() {
        i1 = i2;
    }

    public void testAssignment6() {
        i1 = d2;
    }

    public void testAssignment7() {
        // :: error: assignment.type.incompatible
        d1 = f2;
    }

    public void testAssignment8() {
        // :: error: assignment.type.incompatible
        d1 = i2;
    }

    public void testAssignment9() {
        d1 = d2;
    }
}