Fix pooled params correctness and add context copy benchmark

performance_test.go

@@ -29,7 +29,7 @@ func BenchmarkParameterOperations(b *testing.B) {
 // BenchmarkPathParsing compares old vs new path parsing
 func BenchmarkPathParsingOld(b *testing.B) {
 	path := "/users/123/posts/456/comments/789"
-	
+
 	b.ResetTimer()
 	b.ReportAllocs()
 
@@ -40,7 +40,7 @@ func BenchmarkPathParsingOld(b *testing.B) {
 
 func BenchmarkPathParsingNew(b *testing.B) {
 	path := "/users/123/posts/456/comments/789"
-	
+
 	b.ResetTimer()
 	b.ReportAllocs()
 
@@ -197,4 +197,24 @@ func BenchmarkPoolEfficiency(b *testing.B) {
 		w := httptest.NewRecorder()
 		router.ServeHTTP(w, req)
 	}
-}
+}
+
+// BenchmarkContextParamCopy measures overhead of copying params into context
+func BenchmarkContextParamCopy(b *testing.B) {
+	router := New()
+	router.GET("/users/:id/posts/:postId", func(w http.ResponseWriter, r *http.Request) {
+		params := ParamsFromContext(r)
+		_ = params.Get("id") + params.Get("postId")
+		w.WriteHeader(http.StatusOK)
+	})
+
+	req := httptest.NewRequest("GET", "/users/123/posts/456", nil)
+
+	b.ResetTimer()
+	b.ReportAllocs()
+
+	for i := 0; i < b.N; i++ {
+		w := httptest.NewRecorder()
+		router.ServeHTTP(w, req)
+	}
+}