From d88f23b7e6204ec2c5d4f5d3cda507415308c624 Mon Sep 17 00:00:00 2001
From: Sebastian Wilzbach <seb@wilzba.ch>
Date: Fri, 13 Jan 2017 20:20:56 +0100
Subject: [PATCH] Use appender to build queryString

---
 source/oauth/client.d | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/source/oauth/client.d b/source/oauth/client.d
index 4131451..3341299 100644
--- a/source/oauth/client.d
+++ b/source/oauth/client.d
@@ -149,6 +149,7 @@ class OAuthSettings
         in string[string] extraParams = null,
         in string[] scopes = null) immutable
     {
+        import std.array : Appender;
         import std.random : uniform;
         import std.digest.digest : toHexString;
 
@@ -177,12 +178,14 @@ class OAuthSettings
         httpSession.set("oauth.client", toHexString(this.hash));
 
         URL uri = provider.authUriParsed;
-        auto qs = reqParams.formEncode();
-
+        Appender!string app;
         if (uri.queryString.length)
-            uri.queryString = uri.queryString ~ '&' ~ qs;
-        else
-            uri.queryString = qs;
+        {
+            app.put(uri.queryString);
+            app.put('&');
+        }
+        app.formEncode(reqParams);
+        uri.queryString = app.data;
 
         return uri.toString;
     }