Index: tests/phpunit/tests/media.php
===================================================================
--- tests/phpunit/tests/media.php	(revision 27079)
+++ tests/phpunit/tests/media.php	(working copy)
@@ -364,4 +364,34 @@
 		$matches = get_media_embedded_in_content( $content, $types );
 		$this->assertEquals( $contents, $matches );
 	}
+
+	/**
+	 * @ticket 26768
+	 */
+	function test_add_image_size() {
+		global $_wp_additional_image_sizes;
+		add_image_size( 'test-size', 200, 600 );
+		$this->assertArrayHasKey(  'test-size', $_wp_additional_image_sizes );
+		$this->assertEquals( 200, $_wp_additional_image_sizes[ 'test-size' ]['width'] );
+		$this->assertEquals( 600, $_wp_additional_image_sizes[ 'test-size' ]['height'] );
+	}
+
+	/**
+	 * @ticket 26768
+	 */
+	function test_remove_image_size() {
+		add_image_size( 'test-size', 200, 600 );
+		$this->assertTrue(  has_image_size( 'test-size' ) );
+		remove_image_size( 'test-size' );
+		$this->assertFalse(  has_image_size( 'test-size' ) );
+	}
+
+	/**
+	 * @ticket 26951
+	 */
+	function test_has_image_size() {
+		add_image_size( 'test-size', 200, 600 );
+		$this->assertTrue(  has_image_size( 'test-size' ) );
+	}
+
 }