symfony · fancyweb · Nov 10, 2016 · Nov 10, 2016 · Nov 10, 2016 · Nov 25, 2016
diff --git a/src/Symfony/Component/Routing/RouteCompiler.php b/src/Symfony/Component/Routing/RouteCompiler.php
@@ -28,12 +28,22 @@ class RouteCompiler implements RouteCompilerInterface
     */
    const SEPARATORS = '/,;.:-_~+*=@|';

+    /**
+     * The maximum supported length of a PCRE subpattern name
+     * http://pcre.org/current/doc/html/pcre2pattern.html#SEC16.
+     *
+     * @var int
+     *
+     * @internal
+     */
+    const VARIABLE_MAXIMUM_LENGTH = 32;
+
    /**
     * {@inheritdoc}
     *
     * @throws \LogicException  If a variable is referenced more than once
-     * @throws \DomainException If a variable name is numeric because PHP raises an error for such
-     *                          subpatterns in PCRE and thus would break matching, e.g. "(?P<123>.+)".
+     * @throws \DomainException If a variable name starts with a digit or if it is too long to be successfully used as
+     *                          a PCRE subpattern.
     */
    public static function compile(Route $route)
    {
@@ -95,13 +105,19 @@ private static function compilePattern(Route $route, $pattern, $isHost)
            $precedingChar = strlen($precedingText) > 0 ? substr($precedingText, -1) : '';
            $isSeparator = '' !== $precedingChar && false !== strpos(static::SEPARATORS, $precedingChar);

-            if (is_numeric($varName)) {
-                throw new \DomainException(sprintf('Variable name "%s" cannot be numeric in route pattern "%s". Please use a different name.', $varName, $pattern));
+            // A PCRE subpattern name must start with a non-digit. Also a PHP variable cannot start with a digit so the
+            // variable would not be usable as a Controller action argument.
+            if (preg_match('/^\d/', $varName)) {
+                throw new \DomainException(sprintf('Variable name "%s" cannot start with a digit in route pattern "%s". Please use a different name.', $varName, $pattern));
            }
            if (in_array($varName, $variables)) {
                throw new \LogicException(sprintf('Route pattern "%s" cannot reference variable name "%s" more than once.', $pattern, $varName));
            }

+            if (strlen($varName) > self::VARIABLE_MAXIMUM_LENGTH) {
+                throw new \DomainException(sprintf('Variable name "%s" cannot be longer than %s characters in route pattern "%s". Please use a shorter name.', $varName, self::VARIABLE_MAXIMUM_LENGTH, $pattern));
+            }
+
            if ($isSeparator && strlen($precedingText) > 1) {
                $tokens[] = array('text', substr($precedingText, 0, -1));
            } elseif (!$isSeparator && strlen($precedingText) > 0) {

diff --git a/src/Symfony/Component/Routing/Tests/RouteCompilerTest.php b/src/Symfony/Component/Routing/Tests/RouteCompilerTest.php
@@ -12,6 +12,7 @@
 namespace Symfony\Component\Routing\Tests;

 use Symfony\Component\Routing\Route;
+use Symfony\Component\Routing\RouteCompiler;

 class RouteCompilerTest extends \PHPUnit_Framework_TestCase
 {
@@ -176,16 +177,16 @@ public function testRouteWithSameVariableTwice()
    }

    /**
-     * @dataProvider getNumericVariableNames
+     * @dataProvider getVariableNamesStartingWithADigit
     * @expectedException \DomainException
     */
-    public function testRouteWithNumericVariableName($name)
+    public function testRouteWithVariableNameStartingWithADigit($name)
    {
        $route = new Route('/{'.$name.'}');
        $route->compile();
    }

-    public function getNumericVariableNames()
+    public function getVariableNamesStartingWithADigit()
    {
        return array(
           array('09'),
@@ -264,4 +265,13 @@ public function provideCompileWithHostData()
            ),
        );
    }
+
+    /**
+     * @expectedException \DomainException
+     */
+    public function testRouteWithTooLongVariableName()
+    {
+        $route = new Route(sprintf('/{%s}', str_repeat('a', RouteCompiler::VARIABLE_MAXIMUM_LENGTH + 1)));
+        $route->compile();
+    }
 }