From df9b5ea053d3f3735f2fe29ff0bc35b69e694ba5 Mon Sep 17 00:00:00 2001
From: Alexey Yaroshevich <zxqfox@gmail.com>
Date: Wed, 18 Jan 2017 01:20:44 +0300
Subject: [PATCH 1/3] feat: BemCell.isBemCell method

---
 index.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/index.js b/index.js
index 2305364..35caeaf 100644
--- a/index.js
+++ b/index.js
@@ -104,4 +104,25 @@ module.exports = class BemCell {
 
         return this._id;
     }
+
+    /**
+     * Determines whether specified cell is instance of BemCell.
+     *
+     * @param {BemCell} cell - the cell to check.
+     *
+     * @returns {boolean} A Boolean indicating whether or not specified entity is instance of BemCell.
+     * @example
+     * const BemCell = require('@bem/cell');
+     * const BemEntityName = require('@bem/entity-name');
+     *
+     * const cell = new BemCell({
+     *     entity: new BemEntityName({ block: 'button', elem: 'text' })
+     * });
+     *
+     * BemCell.isBemCell(cell); // true
+     * BemCell.isBemCell({}); // false
+     */
+    static isBemCell(cell) {
+        return cell && this.name === cell.constructor.name;
+    }
 };

From fcfda87b651ec438c1cd9c9ead25ffbc4ead9462 Mon Sep 17 00:00:00 2001
From: Alexey Yaroshevich <zxqfox@gmail.com>
Date: Wed, 18 Jan 2017 01:21:32 +0300
Subject: [PATCH 2/3] tests: BemCell.isBemCell method

---
 test/is-bem-cell.test.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 test/is-bem-cell.test.js

diff --git a/test/is-bem-cell.test.js b/test/is-bem-cell.test.js
new file mode 100644
index 0000000..ddd747e
--- /dev/null
+++ b/test/is-bem-cell.test.js
@@ -0,0 +1,21 @@
+const test = require('ava');
+const BemEntityName = require('@bem/entity-name');
+
+const BemCell = require('../index');
+
+test('should check valid entities', t => {
+    const cell = new BemCell({
+        entity: new BemEntityName({ block: 'block' })
+    });
+
+    t.true(BemCell.isBemCell(cell));
+});
+
+test('should not pass invalid blocks', t => {
+    t.falsy(BemCell.isBemCell({}));
+    t.falsy(BemCell.isBemCell([]));
+});
+
+test('should not pass null', t => {
+    t.falsy(BemCell.isBemCell(null));
+});

From 704395450249da78fb6785e113d147e01f2c62fe Mon Sep 17 00:00:00 2001
From: Alexey Yaroshevich <zxqfox@gmail.com>
Date: Wed, 18 Jan 2017 01:22:11 +0300
Subject: [PATCH 3/3] docs: isBemCell method

---
 README.md | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/README.md b/README.md
index 3f3d819..5d06a46 100644
--- a/README.md
+++ b/README.md
@@ -54,6 +54,7 @@ API
 * [tech](#tech)
 * [layer](#layer)
 * [id](#id)
+* [isBemCell(cell)](#isbemcellcell)
 
 ### constructor(obj)
 
@@ -129,6 +130,26 @@ const cell = new BemCell({
 cell.id; // ➜ "button__text@desktop.css"
 ```
 
+### isBemCell(cell)
+
+Determines whether specified cell is instance of BemCell.
+
+Parameter | Type            | Description
+----------|-----------------|-----------------------
+`cell`    | `BemCell`       | The cell to check.
+
+```js
+const BemCell = require('@bem/cell');
+const BemEntityName = require('@bem/entity-name');
+
+const cell = new BemCell({
+    entity: new BemEntityName({ block: 'button', elem: 'text' })
+});
+
+BemCell.isBemCell(cell); // true
+BemCell.isBemCell({}); // false
+```
+
 License
 -------