Problem3sumTest.java

import org.example.problems._3sum.Solution;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.Arguments;
import org.junit.jupiter.params.provider.MethodSource;

import java.util.Arrays;
import java.util.List;
import java.util.stream.Stream;

public class Problem3sumTest {
 private static Stream<Arguments> provideCases() {
 return Stream.of(
 Arguments.of(
 new int[]{-1, 0, 1, 2, -1, -4},
 new int[][]{{-1, -1, 2}, {-1, 0, 1}}
 ),
 Arguments.of(new int[]{0, 1, 1}, new int[][]{}),
 Arguments.of(new int[]{0, 0, 0}, new int[][]{{0, 0, 0}})
 );
 }

 @ParameterizedTest
 @MethodSource("provideCases")
 public void test(int[] nums, int[][] expected) {
 Solution s = new Solution();

 List<List<Integer>> actual = s.threeSum(nums);

 int[][] converted = actual.stream()
 .map(list -> list.stream().mapToInt(i -> i).toArray())
 .toArray(int[][]::new);

 Assertions.assertTrue(Arrays.deepEquals(expected, converted));
 }
}