Add a new test case

src/tests/BPTreeTests.c

@@ -46,6 +46,20 @@ static bool check_if_the_leaf_nodes_are_correctly_chained(BPTreeNode *root) {
     return true;
 }
 
+static bool check_if_all_leaf_nodes_nodes_have_no_children(BPTreeNode *root) {
+    if (root->is_leaf) {
+        return root->children->size == 0;
+    }
+
+    for (int i = 0; i < root->children->size; i++) {
+        if (!check_if_all_leaf_nodes_nodes_have_no_children(root->children->items[i])) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
 static bool check_if_all_leaf_nodes_have_as_many_keys_as_data(BPTreeNode *root) {
     if (root->is_leaf) {
         return root->keys->size == root->data->size;
@@ -204,6 +218,7 @@ static bool check_BPTree_compliance(BPTreeNode *root) {
     bool is_compliant = true;
 
     is_compliant &= check_if_the_leaf_nodes_are_correctly_chained(root);
+    is_compliant &= check_if_all_leaf_nodes_nodes_have_no_children(root);
     is_compliant &= check_if_all_leaf_nodes_have_as_many_keys_as_data(root);
     is_compliant &= check_if_all_leaf_nodes_are_at_the_same_depth(root, compute_first_leaf_depth(root), 0);