framework/tests/all-systems/Issue807.java

// Test case for Issue #807:
// https://github.com/typetools/checker-framework/issues/807

import java.util.function.Consumer;

public class Issue807 {

  class MyEntry<K, V> {
    MyEntry(MyEntry<? extends K, ? extends V> e) {}
  }

  <K, V> Consumer<MyEntry<K, V>> entryConsumer(Consumer<? super MyEntry<K, V>> action) {
    // The "new MyEntry" isn't a subtype of "? super MyEntry" in
    // most type systems. Suppress that error, as it's not the
    // point of this test.
    @SuppressWarnings("all")
    Consumer<MyEntry<K, V>> res = e -> action.accept(new MyEntry<>(e));
    return res;
  }
}