test: Put tests together in one file

DIRECTORY.md

@@ -10,8 +10,7 @@
   * Heap
     * [Heap](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/data_structures/heap/heap.ts)
     * Test
-      * [Max Heap.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/data_structures/heap/test/max_heap.test.ts)
-      * [Min Heap.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/data_structures/heap/test/min_heap.test.ts)
+      * [Heap.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/data_structures/heap/test/heap.test.ts)
   * List
     * [Doubly Linked List](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/data_structures/list/doubly_linked_list.ts)
     * [Linked List](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/data_structures/list/linked_list.ts)

data_structures/heap/test/min_heap.test.ts → data_structures/heap/test/heap.test.ts

@@ -1,4 +1,57 @@
-import { MinHeap, PriorityQueue } from "../heap";
+import { MaxHeap, MinHeap, PriorityQueue } from "../heap";
+
+describe("MaxHeap", () => {
+  let heap: MaxHeap<number>;
+  const elements: number[] = [
+    12, 4, 43, 42, 9, 7, 39, 16, 55, 1, 51, 34, 81, 18,
+  ];
+
+  beforeEach(() => {
+    heap = new MaxHeap();
+    for (let element of elements) {
+      heap.insert(element);
+    }
+  });
+
+  it("should initialize a heap from input array", () => {
+    expect(heap.isEmpty()).toEqual(false);
+    heap.check();
+  });
+
+  it("should remove and return the max element in the heap", () => {
+    const maxValue = heap.extract();
+
+    expect(maxValue).toEqual(81);
+    heap.check();
+  });
+
+  it("should insert a new element and bubble Up the element to it correct index in the heap", () => {
+    heap.insert(61);
+    heap.check();
+  });
+
+  const extract_all = (heap: MaxHeap<number>) => {
+    [...elements].sort((a, b) => b - a).forEach((element: number) => {
+      expect(heap.extract()).toEqual(element);
+    });
+    heap.check();
+    expect(heap.size()).toEqual(0);
+  }
+
+  it("should remove and return the max elements in order", () => {
+    extract_all(heap);
+  });
+
+  it("should insert all, then remove and return the max elements in order", () => {
+    heap = new MaxHeap();
+    elements.forEach((element: number) => {
+      heap.insert(element);
+    });
+    heap.check();
+    expect(heap.size()).toEqual(elements.length);
+    extract_all(heap);
+  });
+});
 
 describe("MinHeap", () => {
   let heap: MinHeap<number>;