From 03ad4bd0882f966e099d9510c1e0d0c4d294b275 Mon Sep 17 00:00:00 2001
From: Tim Nieradzik <tim@sparse.tech>
Date: Mon, 8 Jul 2019 16:31:38 +0300
Subject: [PATCH] Route: Do not add ampersand if optional parameter is None

---
 shared/src/main/scala/trail/Route.scala    | 11 ++++++-----
 shared/src/test/scala/trail/UrlTests.scala |  7 +++++++
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/shared/src/main/scala/trail/Route.scala b/shared/src/main/scala/trail/Route.scala
index 0c7d4bd..3bc690c 100644
--- a/shared/src/main/scala/trail/Route.scala
+++ b/shared/src/main/scala/trail/Route.scala
@@ -138,11 +138,12 @@ object Route {
   case class ParamRoute[A, P](route: Route[A], param: Param[P]) extends Route[(A, P)] {
     override def url(value: (A, P)): String = {
       val base = route.url(value._1)
-      val encodedParam =
-        param.codec.encode(value._2).map(v => param.name + "=" + URI.encode(v))
-          .getOrElse("")
-      val delimiter = if (base.contains("?")) "&" else "?"
-      base + delimiter + encodedParam
+      param.codec.encode(value._2)
+        .map(v => param.name + "=" + URI.encode(v))
+        .fold(base) { encodedParam =>
+          val delimiter = if (base.contains("?")) "&" else "?"
+          base + delimiter + encodedParam
+        }
     }
     override def parseInternal(path: Path): Option[((A, P), Path)] =
       for {
diff --git a/shared/src/test/scala/trail/UrlTests.scala b/shared/src/test/scala/trail/UrlTests.scala
index e25c078..bd50856 100644
--- a/shared/src/test/scala/trail/UrlTests.scala
+++ b/shared/src/test/scala/trail/UrlTests.scala
@@ -132,4 +132,11 @@ class UrlTests2 extends FunSpec with Matchers {
 
     assert(url == "/list?upload=true")
   }
+
+  it("url() should work with optional parameter set to None") {
+    val route = Root / "disk" / "view" & Param[Long]("disk") & Param[Option[Long]]("folder")
+    val url   = route((48L, None))
+
+    assert(url == "/disk/view?disk=48")
+  }
 }