Add support for single digit version strings, closes shakacode#489

CHANGELOG.md

@@ -5,6 +5,8 @@ Contributors: please follow the recommendations outlined at [keepachangelog.com]
 
 ## [Unreleased]
 
+- React on Rails now correctly parses single-digit version strings from package.json [#491](https://github.com/shakacode/react_on_rails/pull/491)
+
 ## [6.0.5]
 ##### Added
 - Added better error messages to avoid issues with shared redux stores [#470](https://github.com/shakacode/react_on_rails/pull/470).
@@ -27,19 +29,19 @@ Contributors: please follow the recommendations outlined at [keepachangelog.com]
 
 ## [6.0.0]
 ##### Breaking Changes
-- Added automatic compilation of assets at precompile is now done by ReactOnRails. Thus, you don't need to provide your own assets.rake file that does the precompilation. 
+- Added automatic compilation of assets at precompile is now done by ReactOnRails. Thus, you don't need to provide your own assets.rake file that does the precompilation.
   [#398](https://github.com/shakacode/react_on_rails/pull/398) by [robwise](https://github.com/robwise), [jbhatab](https://github.com/jbhatab), and [justin808](https://github.com/justin808).
 - **Migration to v6**
   - Do not run the generator again if you've already run it.
 
   - See [shakacode/react-webpack-rails-tutorial/pull/287](https://github.com/shakacode/react-webpack-rails-tutorial/pull/287) for an    example of upgrading from v5.
-  
+
   - To configure the asset compliation you can either
     1. Specify a `config/react_on_rails` setting for `npm_build_production_command` to be nil to turn this feature off.
     2. Specify the script command you want to run to build your production assets, and remove your assets.rake file.
 
   - If you are using the ReactOnRails test helper, then you will need to add the 'config.npm_build_test_command' to your config to tell react_on_rails what command to run when you run rspec.
-   
+
 - See [shakacode/react-webpack-rails-tutorial #287](https://github.com/shakacode/react-webpack-rails-tutorial/pull/287/files) for an upgrade example. The PR has a few comments on the upgrade.
 
 Here is the addition to the generated config file:
@@ -92,7 +94,7 @@ Here is the addition to the generated config file:
 - [Security] Address failure to sanitize console messages when server rendering and displaying in the browser console. See [#366](https://github.com/shakacode/react_on_rails/pull/366) and [#370](https://github.com/shakacode/react_on_rails/pull/370) by [justin808](https://github.com/justin808)
 
 ##### Added
-- railsContext includes the port number and a boolean if the code is being run on the server or client. 
+- railsContext includes the port number and a boolean if the code is being run on the server or client.
 
 ## [5.1.0] - 2016-04-03
 ##### Added

lib/react_on_rails/version_checker.rb

@@ -3,6 +3,7 @@ module ReactOnRails
   # against each otherat runtime.
   class VersionChecker
     attr_reader :node_package_version, :logger
+    MAJOR_VERSION_REGEX = /(\d+)\.?/
 
     def self.build
       new(NodePackageVersion.build, Rails.logger)
@@ -38,7 +39,7 @@ def gem_version
     end
 
     def gem_major_version
-      gem_version.match(/(\d+)\./)[1]
+      gem_version.match(MAJOR_VERSION_REGEX)[1]
     end
 
     class NodePackageVersion
@@ -66,7 +67,7 @@ def relative_path?
 
       def major
         return if relative_path?
-        raw.match(/(\d+)\./)[1]
+        raw.match(MAJOR_VERSION_REGEX)[1]
       end
 
       private

spec/react_on_rails/version_checker_spec.rb

@@ -47,6 +47,24 @@ module ReactOnRails
           expect(logger.message).to be_nil
         end
       end
+
+      context "when package json uses a one-digit version string" do
+        let(:node_package_version) do
+          double_package_version(raw: "^6", major: "6")
+        end
+
+        it "does not log a warning" do
+          stub_gem_version("6")
+          check_version(node_package_version, logger)
+          expect(logger.message).to be_nil
+        end
+
+        it "logs a warning" do
+          stub_gem_version("5")
+          check_version(node_package_version, logger)
+          expect(logger.message).to be_present
+        end
+      end
     end
 
     def double_package_version(raw: nil, major: nil, relative_path: false)