Add Test to perform syntax-checks on Twig-templates

tests/www/TemplateTest.php

+<?php
+/**
+ * Simple test for syntax-checking Twig-templates.
+ *
+ * @author Tim van Dijen <tvdijen@gmail.com>
+ * @package SimpleSAMLphp
+ */
+
+namespace SimpleSAML\Test\Web;
+
+use PHPUnit\Framework\TestCase;
+
+use \SimpleSAML\Configuration;
+use \SimpleSAML\XHTML\Template;
+use \SimpleSAML\Module;
+
+class TemplateTest extends TestCase
+{
+    public function testSyntax()
+    {
+        $config = Configuration::loadFromArray([
+            'language.i18n.backend' => 'gettext/gettext',
+            'module.enable' => array_fill_keys(Module::getModules(), true),
+        ]);
+        Configuration::setPreLoadedConfig($config);
+
+        $basedir = dirname(dirname(dirname(__FILE__))).DIRECTORY_SEPARATOR.'templates';
+
+        // Base templates
+        $files = array_diff(scandir($basedir), array('.', '..'));
+        foreach ($files as $file) {
+            if (preg_match('/.twig$/', $file)) {
+                $t = new Template($config, $file);
+                ob_start();
+                try {
+                    $t->show();
+                    $this->addToAssertionCount(1);
+                } catch (\Twig_Error_Syntax $e) {
+                    $this->fail($e->getMessage().' in '.$e->getFile().':'.$e->getLine());
+                }
+                ob_clean();
+            }
+        }
+
+        // Module templates
+        foreach (Module::getModules() as $module) {
+            $basedir = Module::getModuleDir($module).DIRECTORY_SEPARATOR.'templates';
+            if (file_exists($basedir)) {
+                $files = array_diff(scandir($basedir), array('.', '..'));
+                foreach ($files as $file) {
+                    if (preg_match('/.twig$/', $file)) {
+                        $t = new Template($config, $module.':'.$file);
+                        ob_start();
+                        try {
+                            $t->show();
+                            $this->addToAssertionCount(1);
+                        } catch (\Twig_Error_Syntax $e) {
+                            $this->fail($e->getMessage().' in '.$e->getFile().':'.$e->getLine());
+                        }
+                        ob_clean();
+                    }
+                }
+            }
+        }
+    }
+}