From b9e95a0b04527cfd45078c3805e22ee84aff3656 Mon Sep 17 00:00:00 2001
From: Landon Reed <landontreed@gmail.com>
Date: Mon, 6 May 2019 14:54:12 -0400
Subject: [PATCH] refactor(merge-feeds): add description for exception

---
 .../manager/controllers/api/FeedVersionController.java        | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/main/java/com/conveyal/datatools/manager/controllers/api/FeedVersionController.java b/src/main/java/com/conveyal/datatools/manager/controllers/api/FeedVersionController.java
index e6edde333..a8be71617 100644
--- a/src/main/java/com/conveyal/datatools/manager/controllers/api/FeedVersionController.java
+++ b/src/main/java/com/conveyal/datatools/manager/controllers/api/FeedVersionController.java
@@ -280,7 +280,9 @@ private static String mergeFeedVersions(Request req, Response res) {
         MergeFeedsType mergeType;
         try {
             mergeType = MergeFeedsType.valueOf(req.queryParams("mergeType"));
-            if (mergeType.equals(REGIONAL)) throw new IllegalArgumentException();
+            if (mergeType.equals(REGIONAL)) {
+                throw new IllegalArgumentException("Regional merge type is not permitted for this endpoint.");
+            }
         } catch (IllegalArgumentException e) {
             logMessageAndHalt(req, 400, "Must provide valid merge type.", e);
             return null;