import java.util.Collections; import java.util.List; import static org.assertj.core.api.Assertions.assertThat; import org.junit.jupiter.api.Disabled; import org.junit.jupiter.api.DisplayName; import org.junit.jupiter.api.Test; public class BinarySearchTreeTest { @Test @DisplayName("data is retained") public void dataIsRetained() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); int expected = 4; binarySearchTree.insert(expected); BinarySearchTree.Node root = binarySearchTree.getRoot(); assertThat(root).isNotNull(); assertThat(root.getData()).isEqualTo(expected); } @Disabled("Remove to run test") @Test @DisplayName("insert data at proper node") public void insertsLess() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); char expectedRoot = '4'; char expectedLeft = '2'; binarySearchTree.insert(expectedRoot); binarySearchTree.insert(expectedLeft); BinarySearchTree.Node root = binarySearchTree.getRoot(); BinarySearchTree.Node left = root.getLeft(); assertThat(root).isNotNull(); assertThat(left).isNotNull(); assertThat(root.getData()).isEqualTo(expectedRoot); assertThat(left.getData()).isEqualTo(expectedLeft); } @Disabled("Remove to run test") @Test @DisplayName("same number at left node") public void insertsSame() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); String expectedRoot = "4"; String expectedLeft = "4"; binarySearchTree.insert(expectedRoot); binarySearchTree.insert(expectedLeft); BinarySearchTree.Node root = binarySearchTree.getRoot(); BinarySearchTree.Node left = root.getLeft(); assertThat(root).isNotNull(); assertThat(left).isNotNull(); assertThat(root.getData()).isEqualTo(expectedRoot); assertThat(left.getData()).isEqualTo(expectedLeft); } @Disabled("Remove to run test") @Test @DisplayName("greater number at right node") public void insertsRight() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); int expectedRoot = 4; int expectedRight = 5; binarySearchTree.insert(expectedRoot); binarySearchTree.insert(expectedRight); BinarySearchTree.Node root = binarySearchTree.getRoot(); BinarySearchTree.Node right = root.getRight(); assertThat(root).isNotNull(); assertThat(right).isNotNull(); assertThat(root.getData()).isEqualTo(expectedRoot); assertThat(right.getData()).isEqualTo(expectedRight); } @Disabled("Remove to run test") @Test @DisplayName("can create complex tree") public void createsComplexTree() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); List expected = List.of('4', '2', '6', '1', '3', '5', '7'); List treeData = List.of('4', '2', '6', '1', '3', '5', '7'); treeData.forEach(binarySearchTree::insert); assertThat(binarySearchTree.getAsLevelOrderList()).isEqualTo(expected); } @Disabled("Remove to run test") @Test @DisplayName("can sort single number") public void sortsSingleElement() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); List expected = Collections.singletonList("2"); binarySearchTree.insert("2"); assertThat(binarySearchTree.getAsSortedList()).isEqualTo(expected); } @Disabled("Remove to run test") @Test @DisplayName("can sort if second number is smaller than first") public void sortsCollectionOfTwoIfSecondInsertedIsSmallerThanFirst() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); List expected = List.of(1, 2); binarySearchTree.insert(2); binarySearchTree.insert(1); assertThat(binarySearchTree.getAsSortedList()).isEqualTo(expected); } @Disabled("Remove to run test") @Test @DisplayName("can sort if second number is same as first") public void sortsCollectionOfTwoIfSecondNumberisSameAsFirst() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); List expected = List.of('2', '2'); binarySearchTree.insert('2'); binarySearchTree.insert('2'); assertThat(binarySearchTree.getAsSortedList()).isEqualTo(expected); } @Disabled("Remove to run test") @Test @DisplayName("can sort if second number is greater than first") public void sortsCollectionOfTwoIfSecondInsertedIsBiggerThanFirst() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); List expected = List.of('2', '3'); binarySearchTree.insert('2'); binarySearchTree.insert('3'); assertThat(binarySearchTree.getAsSortedList()).isEqualTo(expected); } @Disabled("Remove to run test") @Test @DisplayName("can sort complex tree") public void iteratesOverComplexTree() { BinarySearchTree binarySearchTree = new BinarySearchTree<>(); List expected = List.of("1", "2", "3", "5", "6", "7"); List treeData = List.of("2", "1", "3", "6", "7", "5"); treeData.forEach(binarySearchTree::insert); assertThat(binarySearchTree.getAsSortedList()).isEqualTo(expected); } }