fix multiple parameters

Author: davidmartos96

pkgs/shelf_router/lib/src/router_entry.dart

@@ -71,19 +71,24 @@ class RouterEntry {
 
     final params = <ParamInfo>[];
     var pattern = '';
+    // Keep the index where the matches are located
+    // so that we can calculate the positioning of
+    // the extracted parameter
+    var prevMatchIndex = 0;
     for (var m in _parser.allMatches(route)) {
       final firstGroup = m[1]!;
       pattern += RegExp.escape(firstGroup);
       if (m[2] != null) {
         final paramName = m[2]!;
-        final startIdx = firstGroup.length;
-        //final endIdx = startIdx + paramName.length;
+        final startIdx = prevMatchIndex + firstGroup.length;
         final paramInfo = ParamInfo(
           name: paramName,
           startIdx: startIdx,
           endIdx: m.end,
         );
         params.add(paramInfo);
+        prevMatchIndex = m.end;
+
         if (m[3] != null && !_isNoCapture(m[3]!)) {
           throw ArgumentError.value(
               route, 'route', 'expression for "${m[2]}" is capturing');
@@ -139,9 +144,20 @@ class RouterEntry {
   }
 }
 
+/// This class holds information about a parameter extracted
+/// from the route path.
+/// The indexes can by used by the mount logic to resolve the
+/// parametrized path when handling the request.
 class ParamInfo {
+  /// This is the name of the parameter, without <, >
   final String name;
+
+  /// The index in the route String where the parameter
+  /// expression starts (inclusive)
   final int startIdx;
+
+  /// The index in the route String where the parameter
+  /// expression ends (exclusive)
   final int endIdx;
 
   const ParamInfo({

pkgs/shelf_router/test/router_test.dart

@@ -260,6 +260,20 @@ void main() {
     expect(await get('/users/david/no-route'), 'catch-all-handler');
   });
 
+  test('can mount dynamic routes with multiple parameters', () async {
+    var app = Router();
+    app.mount(r'/first/<second>/third/<fourth>/last',
+        (Request request, String second, String fourth) {
+      var router = Router();
+      router.get('/', (r) => Response.ok('$second $fourth'));
+      return router(request);
+    });
+
+    server.mount(app);
+
+    expect(await get('/first/hello/third/bye/last'), 'hello bye');
+  });
+
   test('can mount dynamic routes with regexp', () async {
     var app = Router();