Add unit test for comment_exists().

See #33871.

git-svn-id: https://develop.svn.wordpress.org/trunk@34456 602fd350-edb4-49c9-b593-d223f7449a82

tests/phpunit/tests/admin/includesComment.php

@@ -0,0 +1,22 @@
+<?php
+
+/**
+ * @group admin
+ * @group comment
+ */
+class Tests_Admin_IncludesComment extends WP_UnitTestCase {
+	public function test_must_match_date_and_author() {
+		$c1 = $this->factory->comment->create( array(
+			'comment_author' => 'foo',
+			'comment_date' => '2014-05-06 12:00:00',
+		) );
+
+		$c2 = $this->factory->comment->create( array(
+			'comment_author' => 'bar',
+			'comment_date' => '2004-01-02 12:00:00',
+		) );
+
+		$this->assertNull( comment_exists( 'foo', '2004-01-02 12:00:00' ) );
+		$this->assertEquals( $c1, comment_exists( 'foo', '2014-05-06 12:00:00' ) );
+	}
+}