File: phpunit.xml

<?xml version="1.0" encoding="UTF-8"?>

<phpunit bootstrap="vendor/autoload.php"
         backupGlobals="false"
         backupStaticAttributes="false"
         colors="true"
         convertErrorsToExceptions="true"
         convertNoticesToExceptions="true"
         convertWarningsToExceptions="true"
         processIsolation="false"
         stopOnFailure="false">

    <testsuites>
        <testsuite name="Project Test Suite">
            <directory>tests</directory>
        </testsuite>
    </testsuites>

    <filter>
        <whitelist>
            <directory suffix=".php">src/</directory>
        </whitelist>
    </filter>
    <php>
        <env name="TWILIO_VERSION" value="2010-04-01"/>
        <env name="TWILIO_API_URL" value="https://api.twilio.com/"/>
        <env name="TWILIO_NUMBER" value="+15005550006"/>
        <env name="TWILIO_ERROR_NUMBER" value="+15005550001"/>
        <env name="TWILIO_RECEIVER" value="+15005550006"/>
        <env name="TWILIO_AUTH_TOKEN" value="AUTH_TOKEN"/>
        <env name="TWILIO_SID" value="SID"/>
    </php>
</phpunit>