commit 3f2467a85e71592cdaaca067f923f87351f14d71
Author: pwolanin <pwolanin@49851.no-reply.drupal.org>
Date:   Thu Jan 19 13:31:30 2017 -0500

    almost there

diff --git a/core/lib/Drupal/Core/Routing/RouteCompiler.php b/core/lib/Drupal/Core/Routing/RouteCompiler.php
index dfe2e76..72694e7 100644
--- a/core/lib/Drupal/Core/Routing/RouteCompiler.php
+++ b/core/lib/Drupal/Core/Routing/RouteCompiler.php
@@ -38,7 +38,8 @@ public static function compile(Route $route) {
     // The Drupal-specific compiled information.
     $stripped_path = static::getPathWithoutDefaults($route);
     $fit = static::getFit($stripped_path);
-    $pattern_outline = static::getPatternOutline($stripped_path);
+    // Store a lower-case pattern outline to enable case-insensitive matching.
+    $pattern_outline = Unicode::strtolower(static::getPatternOutline($stripped_path));
     // We count the number of parts including any optional trailing parts. This
     // allows the RouteProvider to filter candidate routes more efficiently.
     $num_parts = count(explode('/', trim($route->getPath(), '/')));
@@ -47,24 +48,28 @@ public static function compile(Route $route) {
       $fit,
       $pattern_outline,
       $num_parts,
-      // These are the Symfony compiled parts.
-      $symfony_compiled->getStaticPrefix(),
-      $symfony_compiled->getRegex(),
+      // These are the compiled parts Symfony uses in
+      // \Symfony\Component\Routing\Matcher\UrlMatcher::matchCollection().
+      // Set the static prefix to an empty string since it is redundant to
+      // the matching in \Drupal\Core\Routing\RouteProvider::getRoutesByPath()
+      // and by skipping it we more easily make the routing case insensitive.
+      '',
+      // Set the regex to use UTF-8 and be case-insensitive.
+      $symfony_compiled->getRegex() . 'ui',
       $symfony_compiled->getTokens(),
       $symfony_compiled->getPathVariables(),
       $symfony_compiled->getHostRegex(),
       $symfony_compiled->getHostTokens(),
       $symfony_compiled->getHostVariables(),
       $symfony_compiled->getVariables()
-      );
+    );
   }
 
   /**
    * Returns the pattern outline.
    *
    * The pattern outline is the path pattern but normalized so that all
-   * placeholders are equal strings and default values are removed, and the path
-   * is converted to lowercase.
+   * placeholders are the string '%'.
    *
    * @param string $path
    *   The path for which we want the normalized outline.
@@ -73,7 +78,7 @@ public static function compile(Route $route) {
    *   The path pattern outline.
    */
   public static function getPatternOutline($path) {
-    return Unicode::strtolower(preg_replace('#\{\w+\}#', '%', $path));
+    return preg_replace('#\{\w+\}#', '%', $path);
   }
 
   /**
diff --git a/core/lib/Drupal/Core/Routing/RouteProvider.php b/core/lib/Drupal/Core/Routing/RouteProvider.php
index d65e1ce..aa20f7e 100644
--- a/core/lib/Drupal/Core/Routing/RouteProvider.php
+++ b/core/lib/Drupal/Core/Routing/RouteProvider.php
@@ -146,17 +146,16 @@ public function getRouteCollectionForRequest(Request $request) {
     // Cache both the system path as well as route parameters and matching
     // routes. We can not yet convert the path to lowercase since wildcard path
     // portions may be case sensitive if they contain data like a base64 encoded
-    // token.
-    $cid = 'route:' . $request->getPathInfo() . ':' . $request->getQueryString();
+    // token. We remove repeated and trailing slashes to normalize the path.
+    $parts = preg_split('@/+@', $request->getPathInfo(), NULL, PREG_SPLIT_NO_EMPTY);
+    $path = '/' . implode('/', $parts);
+    $cid = 'route:' . $path . ':' . $request->getQueryString();
     if ($cached = $this->cache->get($cid)) {
       $this->currentPath->setPath($cached->data['path'], $request);
       $request->query->replace($cached->data['query']);
       return $cached->data['routes'];
     }
     else {
-      $path = $request->getPathInfo();
-      // Just trim path on the right side.
-      $path = $path === '/' ? $path : rtrim($path, '/');
       $path = $this->pathProcessor->processInbound($path, $request);
       $this->currentPath->setPath($path, $request);
       // Incoming path processors may also set query parameters.
@@ -328,8 +327,8 @@ public function getRoutesByPattern($pattern) {
   protected function getRoutesByPath($path) {
     // Split the path up on the slashes, ignoring multiple slashes in a row
     // or leading or trailing slashes. Convert to lower case here so we can
-    // have a case insensitive match from the incoming path to the pattern
-    // outlines from \Drupal\Core\Routing\RouteCompiler::getPatternOutline()
+    // have a case insensitive match from the incoming path to the lower case
+    // pattern outlines from \Drupal\Core\Routing\RouteCompiler::compile().
     $parts = preg_split('@/+@', Unicode::strtolower($path), NULL, PREG_SPLIT_NO_EMPTY);
 
     $collection = new RouteCollection();