[ticket/11162] Extract existing behavior into a function and add a test.

PHPBB3-11162

tests/functions/update_rows_avoiding_duplicates_test.php

@@ -0,0 +1,71 @@
+<?php
+/**
+*
+* @package testing
+* @copyright (c) 2012 phpBB Group
+* @license http://opensource.org/licenses/gpl-2.0.php GNU General Public License v2
+*
+*/
+
+require_once dirname(__FILE__) . '/../../phpBB/includes/functions.php';
+
+class phpbb_update_rows_avoiding_duplicates_test extends phpbb_database_test_case
+{
+	public function getDataSet()
+	{
+		return $this->createXMLDataSet(dirname(__FILE__).'/fixtures/duplicates.xml');
+	}
+
+	public static function fixture_data()
+	{
+		return array(
+			// description
+			// from array
+			// to value
+			// expected count with to value post update
+			array(
+				'trivial',
+				array(1),
+				10,
+				1,
+			),
+			array(
+				'no conflict',
+				array(2),
+				3,
+				2,
+			),
+			array(
+				'conflict',
+				array(4),
+				5,
+				1,
+			),
+			array(
+				'conflict and no conflict',
+				array(6),
+				7,
+				2,
+			),
+		);
+	}
+
+	/**
+	* @dataProvider fixture_data
+	*/
+	public function test_trivial_update($description, $from, $to, $expected_result_count)
+	{
+		$db = $this->new_dbal();
+
+		phpbb_update_rows_avoiding_duplicates($db, TOPICS_WATCH_TABLE, 'topic_id', $from, $to);
+
+		$sql = 'SELECT count(*) AS count
+			FROM ' . TOPICS_WATCH_TABLE . '
+			WHERE topic_id = ' . $db->sql_escape($to);
+		$result = $db->sql_query($sql);
+		$result_count = $db->sql_fetchfield('count');
+		$db->sql_freeresult($result);
+
+		$this->assertEquals($expected_result_count, $result_count);
+	}
+}