src/Composer/Repository/Pear/PackageDependencyParser.php
public function buildDependencyInfo($depArray)
    {
        if (!is_array($depArray)) {
            return new DependencyInfo(array(), array());
        }
        if (!$this->isHash($depArray)) {
            return new DependencyInfo($this->buildDependency10Info($depArray), array());
        }

        return $this->buildDependency20Info($depArray);
    }
public function buildDependencyInfo($depArray)
    {
        if (!is_array($depArray)) {
            return new DependencyInfo(array(), array());
        }
        if (!$this->isHash($depArray)) {
            return new DependencyInfo($this->buildDependency10Info($depArray), array());
        }

        return $this->buildDependency20Info($depArray);
    }
Builds dependency information. It detects used package.xml format.

@param array $depArray
@return DependencyInfo