Issue557.java

// Test case for issue 557:
// https://github.com/typetools/checker-framework/issues/557
// @below-java8-jdk-skip-test

import java.util.Optional;
import org.checkerframework.checker.nullness.qual.Nullable;

@SuppressWarnings("nullness")
class MyOpt<T> {
    static <S> MyOpt<S> of(S p) {
        return null;
    }

    static <S> MyOpt<S> empty() {
        return null;
    }
}

@SuppressWarnings("nullness")
class MyOpt2<T extends Object> {
    static <S extends Object> MyOpt2<S> of(S p) {
        return null;
    }

    static <S extends Object> MyOpt2<S> empty() {
        return null;
    }
}

@SuppressWarnings("nullness")
class MyOpt3<T extends @Nullable Object> {
    static <S extends @Nullable Object> MyOpt3<S> of(S p) {
        return null;
    }

    static <S extends @Nullable Object> MyOpt3<S> empty() {
        return null;
    }
}

class Issue557a {
    MyOpt<String> opt(boolean flag) {
        return flag ? MyOpt.of("Hello") : MyOpt.empty();
    }

    MyOpt<String> opt2() {
        return MyOpt.empty();
    }

    MyOpt<String> opt3(boolean flag) {
        return flag ? MyOpt.of("Hello") : (flag ? MyOpt.empty() : MyOpt.empty());
    }

    void foo(MyOpt<String> param) {}

    void callFoo(boolean flag) {
        foo(flag ? MyOpt.of("Hello") : (flag ? MyOpt.empty() : MyOpt.empty()));
    }
}

class Issue557b {
    MyOpt2<String> opt(boolean flag) {
        return flag ? MyOpt2.of("Hello") : MyOpt2.empty();
    }

    MyOpt2<String> opt2() {
        return MyOpt2.empty();
    }
}

class Issue557c {
    MyOpt3<String> opt(boolean flag) {
        return flag ? MyOpt3.of("Hello") : MyOpt3.empty();
    }

    MyOpt3<String> opt2() {
        return MyOpt3.empty();
    }
}

class Issue557d {
    Optional<String> opt(boolean flag) {
        return flag ? Optional.of("Hello") : Optional.empty();
    }

    Optional<String> opt2() {
        return Optional.empty();
    }
}