framework/tests/all-systems/java8inference/CollectorsToList.java

// Test case for issue #979:
// https://github.com/typetools/checker-framework/issues/979

// @skip-test until the bug is fixed

import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;
import org.checkerframework.checker.nullness.qual.Nullable;

public class CollectorsToList {

  void m(List<String> strings) {
    Stream<String> s = strings.stream();

    // This works:
    List<String> collectedStrings1 = s.collect(Collectors.<String>toList());
    // This works:
    List<@Nullable String> collectedStrings2 = s.collect(Collectors.toList());
    // This works:
    @SuppressWarnings("nullness")
    List<String> collectedStrings3 = s.collect(Collectors.toList());

    // This assignment issues a warning due to incompatible types:
    List<String> collectedStrings = s.collect(Collectors.toList());

    collectedStrings.forEach(System.out::println);
  }
}