feat: add includes method.

Author: ghosind

src/dynamicBuffer.ts

@@ -214,6 +214,31 @@ export class DynamicBuffer {
     return this.buffer[offset];
   }
 
+  /**
+   * Returns a boolean value to indicate whether this buffer includes a certain value among it.
+   *
+   * ```js
+   * buf.append('Hello world');
+   * console.log(buf.includes('world'));
+   * // true
+   * console.log(buf.includes('not in buffer'));
+   * // false
+   * ```
+   *
+   * @param value The value what to search for.
+   * @param byteOffset Where to begin searching in the buffer, and it'll be calculated from the
+   * end of buffer if it's negative. Default `0`.
+   * @param encoding The character encoding if the value is a string, default 'utf8'.
+   * @returns `true` if `value` was found in this buffer, `false` otherwise.
+   */
+  includes(
+    value: string | Buffer | Uint8Array | number | DynamicBuffer,
+    byteOffset: number = 0,
+    encoding: BufferEncoding = 'utf8',
+  ): boolean {
+    return this.indexOf(value, byteOffset, encoding) !== -1;
+  }
+
   /**
    * Gets the first index at which the given value can be found in the buffer, or `-1` if it is
    * not present.

test/search.spec.ts

@@ -92,3 +92,93 @@ describe('IndexOf tests', () => {
     assert.equal(buf.indexOf('', 32), 0);
   });
 });
+
+describe('Includes tests', () => {
+  it('Test includes with empty buffer and empty value.', () => {
+    const buf = new DynamicBuffer();
+
+    assert.equal(buf.includes('Hello'), false);
+    assert.equal(buf.includes(''), true);
+    assert.equal(buf.includes(0), false);
+    assert.equal(buf.includes(Buffer.alloc(0)), true);
+    assert.equal(buf.includes(new Uint8Array()), true);
+    assert.equal(buf.includes(new DynamicBuffer()), true);
+  });
+
+  it('Test includes with empty value.', () => {
+    const buf = new DynamicBuffer();
+    buf.append('Hello world');
+
+    assert.equal(buf.includes(''), true);
+    assert.equal(buf.includes(0), false);
+    assert.equal(buf.includes(Buffer.alloc(0)), true);
+    assert.equal(buf.includes(new Uint8Array()), true);
+    assert.equal(buf.includes(new DynamicBuffer()), true);
+  });
+
+  it('Test includes with string.', () => {
+    const buf = new DynamicBuffer();
+    buf.append('Hello world');
+
+    assert.equal(buf.includes('Hello'), true);
+    assert.equal(buf.includes('world'), true);
+    assert.equal(buf.includes('no'), false);
+  });
+
+  it('Test includes with number.', () => {
+    const buf = new DynamicBuffer();
+    buf.append('Hello world');
+
+    assert.equal(buf.includes(72), true); // H
+    assert.equal(buf.includes(119), true); // w
+    assert.equal(buf.includes(97), false); // a
+  });
+
+  it('Test includes with Buffer.', () => {
+    const buf = new DynamicBuffer();
+    buf.append('Hello world');
+
+    assert.equal(buf.includes(Buffer.from('Hello')), true);
+    assert.equal(buf.includes(Buffer.from('world')), true);
+    assert.equal(buf.includes(Buffer.from('no')), false);
+  });
+
+  it('Test includes with Uint8Array.', () => {
+    const buf = new DynamicBuffer();
+    buf.append('Hello world');
+
+    assert.equal(buf.includes(new Uint8Array([0x48, 0x65, 0x6c, 0x6c, 0x6f])), true);
+    assert.equal(buf.includes(new Uint8Array([0x77, 0x6f, 0x72, 0x6c, 0x64])), true);
+    assert.equal(buf.includes(new Uint8Array([0x6e, 0x6c])), false);
+  });
+
+  it('Test includes with DynamicBuffer.', () => {
+    const buf = new DynamicBuffer();
+    buf.append('Hello world');
+
+    const buf1 = new DynamicBuffer();
+    buf1.append('Hello');
+    assert.equal(buf.includes(buf1), true);
+
+    const buf2 = new DynamicBuffer();
+    buf2.append('world');
+    assert.equal(buf.includes(buf2), true);
+
+    const buf3 = new DynamicBuffer();
+    buf3.append('no');
+    assert.equal(buf.includes(buf3), false);
+  });
+
+  it('Test includes with byteOffset parameter.', () => {
+    const buf = new DynamicBuffer();
+    buf.append('Hello world');
+
+    assert.equal(buf.includes('Hello'), true);
+    assert.equal(buf.includes('Hello', 0), true);
+    assert.equal(buf.includes('Hello', 1), false);
+    assert.equal(buf.includes('Hello', -1), false);
+    assert.equal(buf.includes('Hello', -11), true); // -11 equals 0
+    assert.equal(buf.includes('Hello', 32), false);
+    assert.equal(buf.includes('', 32), true);
+  });
+});