FormatJS i18n argument parsing (#1046)

* Fixed i18n parsing

CHANGELOG.md

@@ -6,6 +6,9 @@ Contributors: please follow the recommendations outlined at [keepachangelog.com]
 ## [Unreleased]
 Changes since last non-beta release.
 
+#### Fixed
+- Changed i18n parsing to convert ruby i18n argument syntax into FormatJS argument syntax. by [sepehr500](https://github.com/sepehr500)  
+
 *Please add entries here for your pull requests that are not yet released.*
 
 ### [10.1.3] - 2018-02-28

lib/react_on_rails/locales_to_js.rb

@@ -108,7 +108,7 @@ def flatten(translations)
         if v.is_a? Hash
           flatten(v).map { |hk, hv| h["#{k}.#{hk}".to_sym] = hv }
         else
-          h[k] = v
+          h[k] = v.gsub("%{", "{")
         end
       end
     end

spec/react_on_rails/fixtures/i18n/locales/en.yml

@@ -1,2 +1,3 @@
 en:
   hello: "Hello world"
+  argument: "I am %{age} years old."

spec/react_on_rails/locales_to_js_spec.rb

@@ -24,7 +24,8 @@ module ReactOnRails
           expect(translations).to include('{"hello":"Hello world"')
           expect(translations).to include('{"hello":"Hallo welt"')
           expect(default).to include("const defaultLocale = 'en';")
-          expect(default).to include('{"hello":{"id":"hello","defaultMessage":"Hello world"}}')
+          expect(default).to include('{"hello":{"id":"hello","defaultMessage":"Hello world"}')
+          expect(default).to include('"argument":{"id":"argument","defaultMessage":"I am {age} years old."}}')
 
           expect(File.mtime(translations_path)).to be >= File.mtime(en_path)
         end