Return empty json when nil in json_safe_and_pretty

CHANGELOG.md

@@ -5,6 +5,7 @@ Contributors: please follow the recommendations outlined at [keepachangelog.com]
 
 ## [Unreleased]
 *Please add entries here for your pull requests.*
+- Return empty json when nil in json_safe_and_pretty [#824](https://github.com/shakacode/react_on_rails/pull/824) by [dzirtusss](https://github.com/dzirtusss)
 
 ## [7.0.3] - 2017-04-27
 Same as 7.0.1.

app/helpers/react_on_rails_helper.rb

@@ -231,7 +231,7 @@ def server_render_js(js_expression, options = {})
   end
 
   def json_safe_and_pretty(hash_or_string)
-    return if hash_or_string.nil?
+    return "{}" if hash_or_string.nil?
     unless hash_or_string.class.in?([Hash, String])
       raise "#{__method__} only accepts String or Hash as argument "\
             "(#{hash_or_string.class} given)."

spec/dummy/spec/helpers/react_on_rails_helper_spec.rb

@@ -32,9 +32,9 @@
       expect { helper.json_safe_and_pretty(false) }.to raise_error
     end
 
-    it "should allow nil values" do
+    it "should return empty json when nil" do
       escaped_json = helper.json_safe_and_pretty(nil)
-      expect(escaped_json).to eq(nil)
+      expect(escaped_json).to eq("{}")
     end
 
     it "converts a hash to escaped JSON" do