Added Unit test for BST insert and delete

Author: SHEEVOOT

.DS_Store

@@ -0,0 +1,35 @@
+const BST = require('.');
+
+describe('Data Structure : Binary Search Tree', () => {
+    it('Should be class', () => {
+        expect(typeof BST.prototype.constructor).toEqual('function');
+    });
+
+    describe('Binary Search Tree API', () => {
+        let bst = null;
+
+        beforeEach(() => {
+            bst = new BST(5);
+        });
+
+        it('Should insert() element to Binary Search Tree', () => {
+            bst.add(4);
+            bst.add(9);
+            bst.add(2);
+            bst.insert(bst.root, 3);
+            expect(bst.traverseInorder()).toEqual([2, 3, 4, 5, 9]);
+            bst.insert(bst.root, 7);
+            expect(bst.traverseInorder()).toEqual([2, 3, 4, 5, 7, 9]);
+        });
+
+        it('Should delete() an element from Binary Search Tree', () => {
+            bst.add(4);
+            bst.add(9);
+            bst.add(2);
+            bst.delete(bst.root, 4);
+            expect(bst.traverseInorder()).toEqual([2, 5, 9]);
+            bst.delete(bst.root, 2);
+            expect(bst.traverseInorder()).toEqual([5, 9]);
+        });
+    });
+});