Handle nil in interpreter/atributes (#163)

CHANGELOG.org

@@ -1,6 +1,6 @@
 * Changelog
 ** Unreleased
-- [[https://github.com/r0man/sablono/issues/158][#158]] Fix camel-case bug in :style attributes.
+- [[https://github.com/r0man/sablono/issues/158][#158]] Fix camel-case bug in :style attributes and handle nil in =interpreter/atributes=.
 - [[https://github.com/r0man/sablono/pull/152][#152]] Don't coerce nil/undefined input :value to be consistent with React.
 - [[https://github.com/r0man/sablono/pull/149][#149]] Force lazy seq in interpret-seq to be realized.
 - [[https://github.com/r0man/sablono/pull/146][#146]] Keep state and props of inputs synchronized.

src/sablono/interpreter.cljc

@@ -113,13 +113,13 @@
 
 #?(:cljs
    (defn attributes [attrs]
-     (let [js-attrs (clj->js (util/html-to-dom-attrs attrs))
-           class (.-className js-attrs)
-           class (if (array? class) (join " " class) class)]
-       (if (blank? class)
-         (js-delete js-attrs "className")
-         (set! (.-className js-attrs) class))
-       js-attrs)))
+     (when-let [js-attrs (clj->js (util/html-to-dom-attrs attrs))]
+       (let [class (.-className js-attrs)
+             class (if (array? class) (join " " class) class)]
+         (if (blank? class)
+           (js-delete js-attrs "className")
+           (set! (.-className js-attrs) class))
+         js-attrs))))
 
 (defn- interpret-seq
   "Interpret the seq `x` as HTML elements."

test/sablono/core_test.cljs

@@ -1307,4 +1307,11 @@
            {:tag :div
             :attributes
             {:style "margin-left:2rem;color:red;"}
+            :content []})))
+  (let [focused? false]
+    (is (= (html-data [:div {:style (merge {:margin-left "2rem"}
+                                           (when focused? {:color "red"}))}])
+           {:tag :div
+            :attributes
+            {:style "margin-left:2rem;"}
             :content []}))))

test/sablono/interpreter_test.cljs

@@ -30,6 +30,7 @@
 (deftest test-attributes
   (are [attrs expected]
       (= expected (js->clj (i/attributes attrs)))
+    nil nil
     {} {}
     {:className ""} {}
     {:className "aa"}       {"className" "aa"}