Improve arguments parsing

src/Handlebars/Arguments.php

@@ -0,0 +1,187 @@
+<?php
+/**
+ * This file is part of Handlebars-php
+ *
+ * PHP version 5.3
+ *
+ * @category  Xamin
+ * @package   Handlebars
+ * @author    Dmitriy Simushev <simushevds@gmail.com>
+ * @copyright 2014 Authors
+ * @license   MIT <http://opensource.org/licenses/MIT>
+ * @version   GIT: $Id$
+ * @link      http://xamin.ir
+ */
+
+namespace Handlebars;
+
+/**
+ * Encapsulates helpers arguments.
+ *
+ * @category  Xamin
+ * @package   Handlebars
+ * @author    Dmitriy Simushev <simushevds@gmail.com>
+ * @copyright 2014 Authors
+ * @license   MIT <http://opensource.org/licenses/MIT>
+ * @version   Release: @package_version@
+ * @link      http://xamin.ir
+ */
+class Arguments
+{
+    /**
+     * List of named arguments.
+     *
+     * @var array
+     */
+    protected $namedArgs = array();
+
+    /**
+     * List of positional arguments.
+     *
+     * @var array
+     */
+    protected $positionalArgs = array();
+
+    /**
+     * The original arguments string that was used to fill in arguments.
+     *
+     * @var string
+     */
+    protected $originalString = '';
+
+    /**
+     * Class constructor.
+     *
+     * @param string $args_string Arguments string as passed to a helper.
+     */
+    public function __construct($args_string = false)
+    {
+        $this->originalString = $args_string;
+
+        if ($args_string) {
+            $this->parse($args_string);
+        }
+    }
+
+    /**
+     * Returns string representation of the arguments list.
+     *
+     * This method is here mostly for backward compatibility reasons.
+     *
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->originalString;
+    }
+
+    /**
+     * Returns a list of named arguments.
+     *
+     * @return array
+     */
+    public function getNamedArguments()
+    {
+        return $this->namedArgs;
+    }
+
+    /**
+     * Returns a list of positional arguments.
+     *
+     * @return array
+     */
+    public function getPositionalArguments()
+    {
+        return $this->positionalArgs;
+    }
+
+    /**
+     * Breaks an argument string into arguments and stores them inside the
+     * object.
+     *
+     * @param string $args_string Arguments string as passed to a helper.
+     *
+     * @return void
+     * @throws \InvalidArgumentException
+     */
+    protected function parse($args_string)
+    {
+        $bad_chars = preg_quote(Context::NOT_VALID_NAME_CHARS, '#');
+        $bad_seg_chars = preg_quote(Context::NOT_VALID_SEGMENT_NAME_CHARS, '#');
+
+        $name_chunk = '(?:[^' . $bad_chars . '\s]+)|(?:\[[^' . $bad_seg_chars . ']+\])';
+        $variable_name = '(?:\.\.\/)*(?:(?:' . $name_chunk . ')[\.\/])*(?:' . $name_chunk  . ')\.?';
+        $escaped_value = '(?:(?<!\\\\)".*?(?<!\\\\)"|(?<!\\\\)\'.*?(?<!\\\\)\')';
+        $argument_name = $name_chunk;
+        $positional_argument = '#^(' . $variable_name . '|' . $escaped_value . ')#';
+        $named_argument = '#^(' . $argument_name . ')\s*=\s*(' . $escaped_value . '|' . $variable_name . ')#';
+
+        $current_str = trim($args_string);
+
+        // Split arguments string
+        while (strlen($current_str) !== 0) {
+            if (preg_match($named_argument, $current_str, $matches)) {
+                // Named argument found
+                $name = $this->prepareArgumentName($matches[1]);
+                $value = $this->prepareArgumentValue($matches[2]);
+
+                $this->namedArgs[$name] = $value;
+
+                // Remove found argument from arguments string.
+                $current_str = ltrim(substr($current_str, strlen($matches[0])));
+            } elseif (preg_match($positional_argument, $current_str, $matches)) {
+                // A positional argument found. It cannot follow named arguments
+                if (count($this->namedArgs) !== 0) {
+                    throw new \InvalidArgumentException('Positional arguments cannot follow named arguments');
+                }
+
+                $this->positionalArgs[] = $this->prepareArgumentValue($matches[1]);
+
+                // Remove found argument from arguments string.
+                $current_str = ltrim(substr($current_str, strlen($matches[0])));
+            } else {
+                throw new \InvalidArgumentException('Malformed arguments string');
+            }
+        }
+    }
+
+    /**
+     * Prepares argument's value to add to arguments list.
+     *
+     * The method unescapes value and wrap it into \Handlebars\String class if
+     * needed.
+     *
+     * @param string $value Argument's value
+     *
+     * @return string|\Handlebars\String
+     */
+    protected function prepareArgumentValue($value)
+    {
+        // Check if argument's value is a quoted string literal
+        if ($value[0] == "'" || $value[0] == '"') {
+            // Remove enclosing quotes and unescape
+            $value = new String(stripcslashes(substr($value, 1, -1)));
+        }
+
+        return $value;
+    }
+
+    /**
+     * Prepares argument's name.
+     *
+     * Remove sections braces if needed.
+     *
+     * @param strign $name Argument's name
+     *
+     * @return string
+     */
+    protected function prepareArgumentName($name)
+    {
+        // Check if argument's name is a segment
+        if ($name[0] == '[') {
+            $name = substr($name, 1, -1);
+        }
+
+        return $name;
+    }
+}

src/Handlebars/Template.php

@@ -590,38 +590,14 @@ class Template
      */
     public function parseNamedArguments($string)
     {
-        $variableName = '(?:(?:[^\'"\[\]\s]|\[.+?\])+)';
+        if ($string instanceof Arguments) {
-        $escapedValue = '(?:(?<!\\\\)".*?(?<!\\\\)"|(?<!\\\\)\'.*?(?<!\\\\)\')';
+            // This code is needed only for backward compatibility
-
+            $args = $string;
-        // Get list of named arguemnts
+        } else {
-        $matches = array();
+            $args = new Arguments($string);
-        preg_match_all(
-            '#(' . $variableName . ')\s*=\s*(' . $escapedValue . '|' . $variableName . ')#',
-            $string,
-            $matches,
-            PREG_SET_ORDER
-        );
-
-        $args = array();
-        for ($x = 0, $c = count($matches); $x < $c; $x++) {
-            $name = $matches[$x][1];
-            $value = $matches[$x][2];
-
-            // Check if argument's name is a segment
-            if ($name[0] == '[') {
-                $name = substr($name, 1, -1);
-            }
-
-            // Check if argument's value is a quoted string literal
-            if ($value[0] == "'" || $value[0] == '"') {
-                // Remove enclosing quotes and unescape
-                $value = new \Handlebars\String(stripcslashes(substr($value, 1, -1)));
-            }
-
-            $args[$name] = $value;
         }
 
-        return $args;
+        return $args->getNamedArguments();
     }
 
     /**
@@ -634,23 +610,13 @@ class Template
      */
     public function parseArguments($string)
     {
-        $args = array();
+        if ($string instanceof Arguments) {
-        preg_match_all('#(?:[^\'"\[\]\s]|\[.+?\])+|(?<!\\\\)("|\')(?:[^\\\\]|\\\\.)*?\1|\S+#s', $string, $args);
+            // This code is needed only for backward compatibility
-        $args = isset($args[0]) ? $args[0] : array();
+            $args = $string;
-
+        } else {
-        for ($x = 0, $argc = count($args); $x < $argc; $x++) {
+            $args = new Arguments($string);
-            // check to see if argument is a quoted string literal
-            if ($args[$x][0] == "'" || $args[$x][0] == '"') {
-                if ($args[$x][0] === substr($args[$x], -1)) {
-                    // remove enclosing quotes and unescape
-                    $args[$x] = new \Handlebars\String(stripcslashes(substr($args[$x], 1, strlen($args[$x]) - 2)));
-                } else {
-                    throw new \RuntimeException("Malformed string: " . $args);
-                }
-            }
-
         }
 
-        return $args;
+        return $args->getPositionalArguments();
     }
 }

tests/Xamin/HandlebarsTest.php

@@ -983,4 +983,14 @@ class HandlebarsTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals('good', $engine->render('{{#with b}}{{#if this}}{{../../a}}{{/if}}{{/with}}', array('a' => 'good', 'b' => 'stump')));
         $this->assertEquals('good', $engine->render('{{#with b}}{{#unless false}}{{../../a}}{{/unless}}{{/with}}', array('a' => 'good', 'b' => 'stump')));
     }
+
+    /**
+     * Test of Arguments to string conversion.
+     */
+    public function testArgumentsString()
+    {
+        $argsString = 'foo bar [foo bar] baz="value"';
+        $args = new \Handlebars\Arguments($argsString);
+        $this->assertEquals($argsString, (string)$args);
+    }
 }