src/Adapter/Phpunit/XmlConfiguration.php
public function addEnvironmentVariable($name, $value)
    {
        $phpNodeList = $this->xpath->query('/phpunit/php');

        if ($phpNodeList->length) {
            $phpNode = $phpNodeList->item(0);
        } else {
            $phpNode = $this->dom->createElement('php');
            $this->rootElement->appendChild($phpNode);
        }

        $env = $this->dom->createElement('env');
        $phpNode->appendChild($env);

        $env->setAttribute('name', $name);
        $env->setAttribute('value', $value);
    }
public function addEnvironmentVariable($name, $value)
    {
        $phpNodeList = $this->xpath->query('/phpunit/php');

        if ($phpNodeList->length) {
            $phpNode = $phpNodeList->item(0);
        } else {
            $phpNode = $this->dom->createElement('php');
            $this->rootElement->appendChild($phpNode);
        }

        $env = $this->dom->createElement('env');
        $phpNode->appendChild($env);

        $env->setAttribute('name', $name);
        $env->setAttribute('value', $value);
    }
Adds a <php><env name="XXX" value="YYY"/></php> to set environment variables
and generates the <php> block if not present.

@param string $name  Environment variable name
@param string $value Value of the variable to set