checker/tests/nullness/java8inference/Issue953bInference.java

// Test case that was submitted in Issue 953, but was combined with Issue 979
// https://github.com/typetools/checker-framework/issues/979

import java.util.*;
import java.util.function.Function;
import org.checkerframework.checker.nullness.qual.NonNull;

public class Issue953bInference {
  private static List<List<?>> strs = new ArrayList<>();

  public static <R, T> List<@NonNull R> mapList(
      List<@NonNull T> list, Function<@NonNull T, @NonNull R> func) {
    ArrayList<@NonNull R> r = new ArrayList<>(list.size());
    for (T t : list) r.add(func.apply(t));
    return r;
  }

  public static List<String> test() {
    return mapList(
        strs,
        s -> {
          return new String();
        });
  }
}