refactor

__tests__/utils/circularBuffer.ts

@@ -0,0 +1,44 @@
+import CircularBuffer from '../../source/utils/circularBuffer'
+
+describe('CircularBuffer', () => {
+    let capacity: number
+    let buffer: CircularBuffer<string>
+
+    beforeEach(() => {
+        capacity = 10
+        buffer = new CircularBuffer<string>(capacity)
+    })
+
+    it('should creates a buffer with the specified capacity', () => {
+        expect(buffer.capacity).toBe(capacity)
+    })
+
+    it('should add item to the buffer', () => {
+        expect(buffer.size).toBe(0)
+        buffer.enqueue('foo')
+        expect(buffer.size).toBe(1)
+    })
+
+    it('should remove oldest item if the buffer is full on adding new items', () => {
+        buffer = new CircularBuffer<string>(2)
+        buffer.enqueue('foo1')
+        buffer.enqueue('foo2')
+        buffer.enqueue('foo3')
+        buffer.enqueue('foo4')
+        expect(buffer.toArray()).toEqual(['foo3', 'foo4'])
+    })
+
+
+    it('should return the current size via the size() getter', () => {
+        buffer.enqueue('foo')
+        expect(buffer.size).toBe(1)
+    })
+
+    it('should return true if buffer is empty', () => {
+        expect(buffer.isEmpty()).toBe(true)
+    })
+
+    it('should throw exception on illegal argument', () => {
+        expect(() => new CircularBuffer<any>(0)).toThrow('The capacity must be > 0')
+    })
+})