Add unit tests

phpunit.xml

+<phpunit bootstrap="vendor/autoload.php" strict="true">
+  <testsuite name="Unit tests">
+    <directory suffix="Test.php">tests/</directory>
+  </testsuite>
+</phpunit>

tests/PicaTest.php

+<?php
+
+/**
+ * This file is part of SimpleSAMLphp Module Pica.
+ *
+ * SimpleSAMLphp Module Pica is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * SimpleSAMLphp Module Pica is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with SimpleSAMLphp Module Pica.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * @author    David Maus <maus@hab.de>
+ * @copyright (c) 2016 by Herzog August Bibliothek Wolfenbüttel
+ * @license   http://www.gnu.org/licenses/gpl.txt GNU General Public License v3 or higher
+ */
+
+use PHPUnit_Framework_TestCase as TestCase;
+
+require_once __DIR__ . '/../lib/Auth/Source/Pica.php';
+
+/**
+ * Unit tests for the Pica authentication source.
+ *
+ * @author    David Maus <maus@hab.de>
+ * @copyright (c) 2016 by Herzog August Bibliothek Wolfenbüttel
+ * @license   http://www.gnu.org/licenses/gpl.txt GNU General Public License v3 or higher
+ */
+class PicaTest extends TestCase
+{
+    /**
+     * @expectedException Exception
+     * @expectedExceptionMessage Unknown pica authentication module
+     */
+    public function testExceptionOnUnknownPicaAuthenticationModule ()
+    {
+        $config = SimpleSAML_Configuration::loadFromArray(array('module' => 'foobar'));
+        $source = $this
+                ->getMockBuilder('sspmod_pica_Auth_Source_Pica')
+                ->disableOriginalConstructor()
+                ->setMethods(null)
+                ->getMock();
+        $source->createAuthenticationModuleFactory($config);
+    }
+}
\ No newline at end of file