<?php

namespace Jonnybarnes\EmojiA11y\Test;

use PHPUnit_Framework_TestCase;
use Jonnybarnes\EmojiA11y\EmojiModifier;

class EmojiModifierTest extends PHPUnit_Framework_TestCase
{
    public function setUp()
    {
        $this->emoji = new EmojiModifier();
    }

    public function tearDown()
    {
        $this->emoji = null;
    }

    public function test_single_emoji()
    {
        $input = 'I’m 😀';
        $excpected = 'I’m <span role="img" aria-label="grinning face">😀</span>';
        $this->assertEquals($excpected, $this->emoji->makeEmojiAccessible($input));
    }
}

<?php

namespace Jonnybarnes\EmojiA11y\Test;

use PHPUnit_Framework_TestCase;
use Jonnybarnes\EmojiA11y\EmojiModifier;

class EmojiModifierTest extends PHPUnit_Framework_TestCase
{
    public function setUp()
    {
        $this->emoji = new EmojiModifier();
    }

    public function tearDown()
    {
        $this->emoji = null;
    }

    public function test_emoji_returns_same()
    {
        $this->assertEquals('Test', $this->emoji->makeEmojiAccessible('Test'));
    }
}

--- 
+++ 
@@ -17,8 +17,10 @@
         $this->emoji = null;
     }
 
-    public function test_emoji_returns_same()
+    public function test_single_emoji()
     {
-        $this->assertEquals('Test', $this->emoji->makeEmojiAccessible('Test'));
+        $input = 'I’m 😀';
+        $excpected = 'I’m <span role="img" aria-label="grinning face">😀</span>';
+        $this->assertEquals($excpected, $this->emoji->makeEmojiAccessible($input));
     }
 }
Make a test for single character emojis
