Introduce abstract class for functional tests.

tests/PhpseclibFunctionalTestCase.php

@@ -0,0 +1,47 @@
+<?php
+/**
+ * @author    Andreas Fischer <bantu@phpbb.com>
+ * @copyright MMXIV Andreas Fischer
+ * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
+ */
+
+abstract class PhpseclibFunctionalTestCase extends PhpseclibTestCase
+{
+    /**
+    * @param string $variable
+    * @param string|null $message
+    *
+    * @return null
+    */
+    protected function requireEnv($variable, $message = null)
+    {
+        if ($this->_getEnv($variable) === false) {
+            $msg = $message ? $message : sprintf(
+                "This test requires the '%s' environment variable.",
+                $this->_prefixEnvVariable($variable)
+            );
+            $this->markTestSkipped($msg);
+        }
+    }
+
+    /**
+    * @param string $variable
+    *
+    * @return string
+    */
+    protected function getEnv($variable)
+    {
+        $this->requireEnv($variable);
+        return $this->_getEnv($variable);
+    }
+
+    private function _getEnv($variable)
+    {
+        return getenv($this->_prefixEnvVariable($variable));
+    }
+
+    private function _prefixEnvVariable($variable)
+    {
+        return 'PHPSECLIB_' . $variable;
+    }
+}