From 62f87292a2ed8622da51a38bf1f60d86e11374ee Mon Sep 17 00:00:00 2001
From: Juho Teperi <juho.teperi@iki.fi>
Date: Wed, 14 Nov 2018 22:31:50 +0200
Subject: [PATCH] Fix #401 if jsprops is nil before adding key, key is lost

If jsprops was nil before key oset call, oset created a new object for
the jsprops, but because the return value from oset was not used, the
object was lost.
---
 src/reagent/impl/template.cljs    | 5 +++--
 test/reagenttest/testreagent.cljs | 8 ++++++--
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/src/reagent/impl/template.cljs b/src/reagent/impl/template.cljs
index 7dfa83f..e9fc660 100644
--- a/src/reagent/impl/template.cljs
+++ b/src/reagent/impl/template.cljs
@@ -323,9 +323,10 @@
   (let [props (nth argv 1 nil)
         hasprops (or (nil? props) (map? props))
         jsprops (convert-prop-value (if hasprops props))
+        jsprops (if-some [key (key-from-vec argv)]
+                  (oset jsprops "key" key)
+                  jsprops)
         first-child (+ 1 (if hasprops 1 0))]
-    (when-some [key (key-from-vec argv)]
-      (oset jsprops "key" key))
     (make-element argv react/Fragment jsprops first-child)))
 
 (defn adapt-react-class
diff --git a/test/reagenttest/testreagent.cljs b/test/reagenttest/testreagent.cljs
index 7c74e19..b870543 100644
--- a/test/reagenttest/testreagent.cljs
+++ b/test/reagenttest/testreagent.cljs
@@ -1189,8 +1189,12 @@
                      [:div "hello"]
                      [:div "world"]]
                     ^{:key 2}
-                    [children])])]
-      (is (= "<div><div>hello</div><div>world</div><div>foo</div></div>"
+                    [children]
+                    ^{:key 3}
+                    [:<>
+                     [:div "1"]
+                     [:div "2"]])])]
+      (is (= "<div><div>hello</div><div>world</div><div>foo</div><div>1</div><div>2</div></div>"
              (as-string [comp]))))))
 
 (defonce my-context (react/createContext "default"))