diff --git a/tests/phpunit/tests/comment/getCommentClass.php b/tests/phpunit/tests/comment/getCommentClass.php
new file mode 100644
index 0000000000..c7ce64923b
--- /dev/null
+++ b/tests/phpunit/tests/comment/getCommentClass.php
@@ -0,0 +1,39 @@
+<?php
+
+/**
+ * @group comment
+ */
+class Tests_Comment_GetCommentClass extends WP_UnitTestCase {
+	public function test_should_accept_comment_id() {
+		$post_id    = $this->factory->post->create();
+		$comment_id = $this->factory->comment->create( array( 'comment_post_ID' => $post_id ) );
+
+		$classes = get_comment_class( '', $comment_id );
+		$this->assertContains( 'comment', $classes );
+	}
+
+	public function test_should_accept_comment_object() {
+		$post_id = $this->factory->post->create();
+		$comment = $this->factory->comment->create_and_get( array( 'comment_post_ID' => $post_id ) );
+
+		$classes = get_comment_class( '', $comment );
+		$this->assertContains( 'comment', $classes );
+	}
+
+	public function test_should_append_single_class() {
+		$post_id    = $this->factory->post->create();
+		$comment_id = $this->factory->comment->create( array( 'comment_post_ID' => $post_id ) );
+
+		$classes = get_comment_class( 'foo', $comment_id );
+		$this->assertContains( 'foo', $classes );
+	}
+
+	public function test_should_append_array_of_classes() {
+		$post_id    = $this->factory->post->create();
+		$comment_id = $this->factory->comment->create( array( 'comment_post_ID' => $post_id ) );
+
+		$classes = get_comment_class( array( 'foo', 'bar' ), $comment_id );
+		$this->assertContains( 'foo', $classes );
+		$this->assertContains( 'bar', $classes );
+	}
+}