DI\Container: added expand()

Nette/DI/Container.php

@@ -263,6 +263,30 @@ public function getParam($key, $default = NULL)
 
 
 
+	/**
+	 * Expands %placeholders% in string.
+	 * @param  string
+	 * @return string
+	 * @throws Nette\InvalidStateException
+	 */
+	public function expand($s)
+	{
+		if (is_string($s) && strpos($s, '%') !== FALSE) {
+			$that = $this;
+			return @preg_replace_callback('#%([a-z0-9._-]*)%#i', function ($m) use ($that) { // intentionally @ due PHP bug #39257
+				list(, $param) = $m;
+				$val = $param === '' ? '%' : $that->getParam($param);
+				if (!is_scalar($val)) {
+					throw new Nette\InvalidStateException("Parameter '$param' is not scalar.");
+				}
+				return $val;
+			}, $s);
+		}
+		return $s;
+	}
+
+
+
 	/********************* shortcuts ****************d*g**/
 
 

tests/Nette/DI/Container.expand.phpt

@@ -0,0 +1,37 @@
+<?php
+
+/**
+ * Test: Nette\DI\Container expand.
+ *
+ * @author     David Grudl
+ * @package    Nette
+ * @subpackage UnitTests
+ */
+
+use Nette\DI\Container;
+
+
+
+require __DIR__ . '/../bootstrap.php';
+
+
+
+$container = new Container;
+$container->params['appDir'] = '/myApp';
+
+Assert::same( '/myApp/test', $container->expand('%appDir%/test') );
+
+try {
+	$container->expand('%bar%');
+	Assert::fail('Expected exception');
+} catch (Exception $e) {
+	Assert::exception('Nette\InvalidStateException', "Missing parameter 'bar'.", $e );
+}
+
+try {
+	$container->params['bar'] = array();
+	$container->expand('%bar%');
+	Assert::fail('Expected exception');
+} catch (Exception $e) {
+	Assert::exception('Nette\InvalidStateException', "Parameter 'bar' is not scalar.", $e );
+}