add instance method to VersionChecker

Author: Judahmeek

lib/react_on_rails/engine.rb

@@ -5,8 +5,8 @@
 module ReactOnRails
   class Engine < ::Rails::Engine
     config.to_prepare do
-      if VersionChecker.new(NodePackageVersion.new("package.json")).raise_if_gem_and_node_package_versions_differ &&
-         VersionChecker.new(NodePackageVersion.new("client/package.json")).raise_if_gem_and_node_package_versions_differ
+      if VersionChecker.instance("package.json").raise_if_gem_and_node_package_versions_differ &&
+         VersionChecker.instance("client/package.json").raise_if_gem_and_node_package_versions_differ
         Rails.logger.warn("No 'react-on-rails' entry found in 'dependencies' in package.json or client/package.json.")
       end
       ReactOnRails::ServerRenderingPool.reset_pool

lib/react_on_rails/version_checker.rb

@@ -12,6 +12,10 @@ def self.build
       new(NodePackageVersion.build)
     end
 
+    def self.instance(package_json_path)
+      new(NodePackageVersion.new(package_json_path))
+    end
+
     def initialize(node_package_version)
       @node_package_version = node_package_version
     end