From df6d6447880184ae6229da85216ecee475bd1666 Mon Sep 17 00:00:00 2001
From: Steve Howell <showell30@yahoo.com>
Date: Sat, 4 Mar 2017 09:49:32 -0800
Subject: [PATCH] refactor: Extract get_sub_for_target().

---
 static/js/subs.js | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/static/js/subs.js b/static/js/subs.js
index 9403598260..ec66be89a3 100644
--- a/static/js/subs.js
+++ b/static/js/subs.js
@@ -85,12 +85,27 @@ function get_stream_id(target) {
     return target.closest(".stream-row, .subscription_settings").attr("data-stream-id");
 }
 
+function get_sub_for_target(target) {
+    var stream_id = get_stream_id(target);
+    if (!stream_id) {
+        blueslip.error('Cannot find stream id for target');
+        return;
+    }
+
+    var sub = stream_data.get_sub_by_id(stream_id);
+    if (!sub) {
+        blueslip.error('get_sub_for_target() failed id lookup: ' + stream_id);
+        return;
+    }
+    return sub;
+}
+
 // Finds the stream name of a jquery object that's inside a
 // .stream-row or .subscription_settings element.
 function get_stream_name(target) {
-    var stream = stream_data.get_sub_by_id(get_stream_id(target));
-    if (stream) {
-        return stream.name;
+    var sub = get_sub_for_target(target);
+    if (sub) {
+        return sub.name;
     }
 }