[Wiki] Access log output from unit tests

<?php
class DebugLogRoute extends CLogRoute
{
    /**
     * @var array list of messages in this format:
     * array(
     *   [0] => message (string)
     *   [1] => level (string)
     *   [2] => category (string)
     *   [3] => timestamp (float, obtained by microtime(true)
     *  )
     */
    public static $messages=array();
 
    protected function processLogs($logs)
    {
        foreach($logs as $log)
            self::$messages[]=$log;
    }
 
    /**
     * Reset collected messages
     */
    public static function flushMessages()
    {
        self::$messages=array();
    }
 
    /**
     * @param string $pattern regex pattern to search for
     * @param mixed $l optional level to search for
     * @param mixed $c optional category to search for
     * @return bool wether message with given pattern, level and category was found
     */
    public static function hasMessage($pattern, $l=null, $c=null)
    {
        foreach(self::$messages as $m)
            if(
                preg_match($pattern, $m[0]) && 
                ($l===null || $m[1]===$l) && 
                ($c===null || $m[2]===$c)
            )
                return true;
 
        return false;
    }
}

<?php
'components'=>array(
    'log'=>array(
        'class'=>'CLogRouter',
        'routes'=>array(
            array('class'=>'DebugLogRoute')
        ),
    ),
    ...

<?php
public function testSomething()
{
    $logger = Yii::getLogger();
 
    // Flush all messages so far and reset debug log route
    $logger->flush(true);
    DebugLogRoute::flushMessages();
 
    // ... do tests and add log messages here ...
 
    $logger->flush(true);
    $logs=DebugLogRoute::$messages;
 
    // Inspect logs, for example:
    $this->assertTrue(
        DebugLogRoute::hasMessage('Serving .* from cache', 
        'trace',
        'system.caching.CApcCache'
    );
 
    DebugLogRoute::flushMessages();
 
    // ... more tests ...
 
    $logger->flush(true);
    $logs=DebugLogRoute::$messages;
 
    // ... inspect $logs ...
}