vendor/symfony/src/Symfony/Component/Templating/PhpEngine.php
changeset 0 7f95f8617b0b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vendor/symfony/src/Symfony/Component/Templating/PhpEngine.php	Sat Sep 24 15:40:41 2011 +0200
@@ -0,0 +1,546 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Templating;
+
+use Symfony\Component\Templating\Storage\Storage;
+use Symfony\Component\Templating\Storage\FileStorage;
+use Symfony\Component\Templating\Storage\StringStorage;
+use Symfony\Component\Templating\Helper\HelperInterface;
+use Symfony\Component\Templating\Loader\LoaderInterface;
+
+/**
+ * PhpEngine is an engine able to render PHP templates.
+ *
+ * @author Fabien Potencier <fabien@symfony.com>
+ *
+ * @api
+ */
+class PhpEngine implements EngineInterface, \ArrayAccess
+{
+    protected $loader;
+    protected $current;
+    protected $helpers;
+    protected $parents;
+    protected $stack;
+    protected $charset;
+    protected $cache;
+    protected $escapers;
+    protected $globals;
+    protected $parser;
+
+    /**
+     * Constructor.
+     *
+     * @param TemplateNameParserInterface $parser  A TemplateNameParserInterface instance
+     * @param LoaderInterface             $loader  A loader instance
+     * @param array                       $helpers An array of helper instances
+     */
+    public function __construct(TemplateNameParserInterface $parser, LoaderInterface $loader, array $helpers = array())
+    {
+        $this->parser  = $parser;
+        $this->loader  = $loader;
+        $this->parents = array();
+        $this->stack   = array();
+        $this->charset = 'UTF-8';
+        $this->cache   = array();
+        $this->globals = array();
+
+        $this->setHelpers($helpers);
+
+        $this->initializeEscapers();
+        foreach ($this->escapers as $context => $escaper) {
+            $this->setEscaper($context, $escaper);
+        }
+    }
+
+    /**
+     * Renders a template.
+     *
+     * @param mixed $name       A template name or a TemplateReferenceInterface instance
+     * @param array $parameters An array of parameters to pass to the template
+     *
+     * @return string The evaluated template as a string
+     *
+     * @throws \InvalidArgumentException if the template does not exist
+     * @throws \RuntimeException         if the template cannot be rendered
+     *
+     * @api
+     */
+    public function render($name, array $parameters = array())
+    {
+        $storage = $this->load($name);
+        $key = md5(serialize($storage));
+        $this->current = $key;
+        $this->parents[$key] = null;
+
+        // attach the global variables
+        $parameters = array_replace($this->getGlobals(), $parameters);
+        // render
+        if (false === $content = $this->evaluate($storage, $parameters)) {
+            throw new \RuntimeException(sprintf('The template "%s" cannot be rendered.', $this->parser->parse($name)));
+        }
+
+        // decorator
+        if ($this->parents[$key]) {
+            $slots = $this->get('slots');
+            $this->stack[] = $slots->get('_content');
+            $slots->set('_content', $content);
+
+            $content = $this->render($this->parents[$key], $parameters);
+
+            $slots->set('_content', array_pop($this->stack));
+        }
+
+        return $content;
+    }
+
+    /**
+     * Returns true if the template exists.
+     *
+     * @param mixed $name A template name or a TemplateReferenceInterface instance
+     *
+     * @return Boolean true if the template exists, false otherwise
+     *
+     * @api
+     */
+    public function exists($name)
+    {
+        try {
+            $this->load($name);
+        } catch (\InvalidArgumentException $e) {
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Returns true if this class is able to render the given template.
+     *
+     * @param mixed $name A template name or a TemplateReferenceInterface instance
+     *
+     * @return Boolean true if this class supports the given resource, false otherwise
+     *
+     * @api
+     */
+    public function supports($name)
+    {
+        $template = $this->parser->parse($name);
+
+        return 'php' === $template->get('engine');
+    }
+
+    /**
+     * Evaluates a template.
+     *
+     * @param Storage $template   The template to render
+     * @param array   $parameters An array of parameters to pass to the template
+     *
+     * @return string|false The evaluated template, or false if the engine is unable to render the template
+     */
+    protected function evaluate(Storage $template, array $parameters = array())
+    {
+        $__template__ = $template;
+        if ($__template__ instanceof FileStorage) {
+            extract($parameters);
+            $view = $this;
+            ob_start();
+            require $__template__;
+
+            return ob_get_clean();
+        } elseif ($__template__ instanceof StringStorage) {
+            extract($parameters);
+            $view = $this;
+            ob_start();
+            eval('; ?>'.$__template__.'<?php ;');
+
+            return ob_get_clean();
+        }
+
+        return false;
+    }
+
+    /**
+     * Gets a helper value.
+     *
+     * @param string $name The helper name
+     *
+     * @return mixed The helper value
+     *
+     * @throws \InvalidArgumentException if the helper is not defined
+     *
+     * @api
+     */
+    public function offsetGet($name)
+    {
+        return $this->get($name);
+    }
+
+    /**
+     * Returns true if the helper is defined.
+     *
+     * @param string  $name The helper name
+     *
+     * @return Boolean true if the helper is defined, false otherwise
+     *
+     * @api
+     */
+    public function offsetExists($name)
+    {
+        return isset($this->helpers[$name]);
+    }
+
+    /**
+     * Sets a helper.
+     *
+     * @param HelperInterface $name  The helper instance
+     * @param string          $value An alias
+     *
+     * @api
+     */
+    public function offsetSet($name, $value)
+    {
+        $this->set($name, $value);
+    }
+
+    /**
+     * Removes a helper.
+     *
+     * @param string $name The helper name
+     *
+     * @api
+     */
+    public function offsetUnset($name)
+    {
+        throw new \LogicException(sprintf('You can\'t unset a helper (%s).', $name));
+    }
+
+    /**
+     * @param Helper[] $helpers An array of helper
+     *
+     * @api
+     */
+    public function addHelpers(array $helpers)
+    {
+        foreach ($helpers as $alias => $helper) {
+            $this->set($helper, is_int($alias) ? null : $alias);
+        }
+    }
+
+    /**
+     * Sets the helpers.
+     *
+     * @params Helper[] $helpers An array of helper
+     *
+     * @api
+     */
+    public function setHelpers(array $helpers)
+    {
+        $this->helpers = array();
+        $this->addHelpers($helpers);
+    }
+
+    /**
+     * Sets a helper.
+     *
+     * @param HelperInterface $helper The helper instance
+     * @param string          $alias  An alias
+     *
+     * @api
+     */
+    public function set(HelperInterface $helper, $alias = null)
+    {
+        $this->helpers[$helper->getName()] = $helper;
+        if (null !== $alias) {
+            $this->helpers[$alias] = $helper;
+        }
+
+        $helper->setCharset($this->charset);
+    }
+
+    /**
+     * Returns true if the helper if defined.
+     *
+     * @param string  $name The helper name
+     *
+     * @return Boolean true if the helper is defined, false otherwise
+     *
+     * @api
+     */
+    public function has($name)
+    {
+        return isset($this->helpers[$name]);
+    }
+
+    /**
+     * Gets a helper value.
+     *
+     * @param string $name The helper name
+     *
+     * @return HelperInterface The helper instance
+     *
+     * @throws \InvalidArgumentException if the helper is not defined
+     *
+     * @api
+     */
+    public function get($name)
+    {
+        if (!isset($this->helpers[$name])) {
+            throw new \InvalidArgumentException(sprintf('The helper "%s" is not defined.', $name));
+        }
+
+        return $this->helpers[$name];
+    }
+
+    /**
+     * Decorates the current template with another one.
+     *
+     * @param string $template  The decorator logical name
+     *
+     * @api
+     */
+    public function extend($template)
+    {
+        $this->parents[$this->current] = $template;
+    }
+
+    /**
+     * Escapes a string by using the current charset.
+     *
+     * @param mixed  $value   A variable to escape
+     * @param string $context The context name
+     *
+     * @return string The escaped value
+     *
+     * @api
+     */
+    public function escape($value, $context = 'html')
+    {
+        return call_user_func($this->getEscaper($context), $value);
+    }
+
+    /**
+     * Sets the charset to use.
+     *
+     * @param string $charset The charset
+     *
+     * @api
+     */
+    public function setCharset($charset)
+    {
+        $this->charset = $charset;
+    }
+
+    /**
+     * Gets the current charset.
+     *
+     * @return string The current charset
+     *
+     * @api
+     */
+    public function getCharset()
+    {
+        return $this->charset;
+    }
+
+    /**
+     * Adds an escaper for the given context.
+     *
+     * @param string $context The escaper context (html, js, ...)
+     * @param mixed  $escaper A PHP callable
+     *
+     * @api
+     */
+    public function setEscaper($context, $escaper)
+    {
+        $this->escapers[$context] = $escaper;
+    }
+
+    /**
+     * Gets an escaper for a given context.
+     *
+     * @param string $context The context name
+     *
+     * @return mixed  $escaper A PHP callable
+     *
+     * @api
+     */
+    public function getEscaper($context)
+    {
+        if (!isset($this->escapers[$context])) {
+            throw new \InvalidArgumentException(sprintf('No registered escaper for context "%s".', $context));
+        }
+
+        return $this->escapers[$context];
+    }
+
+    /**
+     * @param string $name
+     * @param mixed $value
+     *
+     * @api
+     */
+    public function addGlobal($name, $value)
+    {
+        $this->globals[$name] = $value;
+    }
+
+    /**
+     * Returns the assigned globals.
+     *
+     * @return array
+     *
+     * @api
+     */
+    public function getGlobals()
+    {
+        return $this->globals;
+    }
+
+    /**
+     * Initializes the built-in escapers.
+     *
+     * Each function specifies a way for applying a transformation to a string
+     * passed to it. The purpose is for the string to be "escaped" so it is
+     * suitable for the format it is being displayed in.
+     *
+     * For example, the string: "It's required that you enter a username & password.\n"
+     * If this were to be displayed as HTML it would be sensible to turn the
+     * ampersand into '&amp;' and the apostrophe into '&aps;'. However if it were
+     * going to be used as a string in JavaScript to be displayed in an alert box
+     * it would be right to leave the string as-is, but c-escape the apostrophe and
+     * the new line.
+     *
+     * For each function there is a define to avoid problems with strings being
+     * incorrectly specified.
+     */
+    protected function initializeEscapers()
+    {
+        $that = $this;
+
+        $this->escapers = array(
+            'html' =>
+                /**
+                 * Runs the PHP function htmlspecialchars on the value passed.
+                 *
+                 * @param string $value the value to escape
+                 *
+                 * @return string the escaped value
+                 */
+                function ($value) use ($that)
+                {
+                    // Numbers and Boolean values get turned into strings which can cause problems
+                    // with type comparisons (e.g. === or is_int() etc).
+                    return is_string($value) ? htmlspecialchars($value, ENT_QUOTES, $that->getCharset(), false) : $value;
+                },
+
+            'js' =>
+                /**
+                 * A function that escape all non-alphanumeric characters
+                 * into their \xHH or \uHHHH representations
+                 *
+                 * @param string $value the value to escape
+                 * @return string the escaped value
+                 */
+                function ($value) use ($that)
+                {
+                    if ('UTF-8' != $that->getCharset()) {
+                        $value = $that->convertEncoding($value, 'UTF-8', $that->getCharset());
+                    }
+
+                    $callback = function ($matches) use ($that)
+                    {
+                        $char = $matches[0];
+
+                        // \xHH
+                        if (!isset($char[1])) {
+                            return '\\x'.substr('00'.bin2hex($char), -2);
+                        }
+
+                        // \uHHHH
+                        $char = $that->convertEncoding($char, 'UTF-16BE', 'UTF-8');
+
+                        return '\\u'.substr('0000'.bin2hex($char), -4);
+                    };
+
+                    if (null === $value = preg_replace_callback('#[^\p{L}\p{N} ]#u', $callback, $value)) {
+                        throw new \InvalidArgumentException('The string to escape is not a valid UTF-8 string.');
+                    }
+
+                    if ('UTF-8' != $that->getCharset()) {
+                        $value = $that->convertEncoding($value, $that->getCharset(), 'UTF-8');
+                    }
+
+                    return $value;
+                },
+        );
+    }
+
+    /**
+     * Convert a string from one encoding to another.
+     *
+     * @param string $string The string to convert
+     * @param string $to     The input encoding
+     * @param string $from   The output encoding
+     *
+     * @return string The string with the new encoding
+     *
+     * @throws \RuntimeException if no suitable encoding function is found (iconv or mbstring)
+     */
+    public function convertEncoding($string, $to, $from)
+    {
+        if (function_exists('iconv')) {
+            return iconv($from, $to, $string);
+        } elseif (function_exists('mb_convert_encoding')) {
+            return mb_convert_encoding($string, $to, $from);
+        }
+
+        throw new \RuntimeException('No suitable convert encoding function (use UTF-8 as your encoding or install the iconv or mbstring extension).');
+    }
+
+    /**
+     * Gets the loader associated with this engine.
+     *
+     * @return LoaderInterface A LoaderInterface instance
+     */
+    public function getLoader()
+    {
+        return $this->loader;
+    }
+
+    /**
+     * Loads the given template.
+     *
+     * @param mixed $name A template name or a TemplateReferenceInterface instance
+     *
+     * @return Storage A Storage instance
+     *
+     * @throws \InvalidArgumentException if the template cannot be found
+     */
+    protected function load($name)
+    {
+        $template = $this->parser->parse($name);
+
+        $key = $template->getLogicalName();
+        if (isset($this->cache[$key])) {
+            return $this->cache[$key];
+        }
+
+        $storage = $this->loader->load($template);
+
+        if (false === $storage) {
+            throw new \InvalidArgumentException(sprintf('The template "%s" does not exist.', $template));
+        }
+
+        return $this->cache[$key] = $storage;
+    }
+}