Fix 500, update Ruby

.ruby-version

@@ -1 +1 @@
-2.6.2
+2.6.5

Gemfile

@@ -2,7 +2,7 @@
 
 source "http://rubygems.org"
 
-ruby "2.6.2"
+ruby "2.6.5"
 
 gem "rails", "~> 6.0"
 gem "doorkeeper", "~> 5.4.0"

Gemfile.lock

@@ -248,7 +248,7 @@ DEPENDENCIES
   uglifier
 
 RUBY VERSION
-   ruby 2.6.2p47
+   ruby 2.6.5p114
 
 BUNDLED WITH
-   2.0.1
+   2.1.4

README.md

@@ -65,11 +65,13 @@ namespace :api do
 end
 ```
 
-We namespace the API controllers to avoid name clashing and collisions between your existing application and the API. This way, you can make changes to your application without messing up with the API's behavior.
+We namespace the API controllers to avoid name clashing and collisions between your existing application and the API.
+This way, you can make changes to your application without messing up with the API's behavior.
 
 You can find all controllers under `/app/controllers/api/v1` folder.
 
-The `api_controller.rb` works as a parent class to the other controllers. It only defines a method that returns the current resource owner, based on the access token:
+The `api_controller.rb` works as a parent class to the other controllers. It only defines a method that returns
+the current resource owner, based on the access token:
 
 ``` ruby
 def current_resource_owner
@@ -81,7 +83,8 @@ This is required if you want to return data based on the current user, like in `
 
 ### Make Access Token Required
 
-To make your API only available for OAuth users, you need to tell doorkeeper to require an access token in your api controller, like this:
+To make your API only available for OAuth users, you need to tell doorkeeper to require an access token in
+your api controller, like this:
 
 ``` ruby
 module Api::V1
@@ -103,4 +106,5 @@ If you attempt to access any of the protected resources without an proper access
 
 You can manage all client applications in `/oauth/applications`.
 
-If you want to create a client application, check out [this example using Sinatra](http://doorkeeper-sinatra.herokuapp.com) and this [another one using Rails and Devise](http://doorkeeper-devise.herokuapp.com).
+If you want to create a client application, check out [this example using Sinatra](http://doorkeeper-sinatra.herokuapp.com)
+and this [another one using Rails and Devise](http://doorkeeper-devise.herokuapp.com).

app/views/home/index.html.erb

@@ -1,6 +1,6 @@
 <div class="row">
   <div class="col">
-    <h1 class="display-4">Doorkeeper <span class="badge badge-primary"><%= Doorkeeper.gem_version %></span></h1>
+    <h1 class="display-4">Doorkeeper <span class="badge badge-primary"><%= Doorkeeper::VERSION::STRING %></span></h1>
 
     <p class="lead">
       <a href="https://github.com/applicake/doorkeeper">Doorkeeper</a> is an <a href="http://oauth.net/2/">OAuth 2</a> provider for <a href="http://rubyonrails.org/">Rails</a>.

bin/bundle

@@ -11,7 +11,7 @@
 require "rubygems"
 
 m = Module.new do
-    module_function
+  module_function
 
   def invoked_as_script?
     File.expand_path($0) == File.expand_path(__FILE__)
@@ -31,7 +31,7 @@ m = Module.new do
         bundler_version = a
       end
       next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
-      bundler_version = $1 || ">= 0.a"
+      bundler_version = $1
       update_index = i
     end
     bundler_version
@@ -61,32 +61,41 @@ m = Module.new do
   end
 
   def bundler_version
-    @bundler_version ||= begin
+    @bundler_version ||=
       env_var_version || cli_arg_version ||
-        lockfile_version || "#{Gem::Requirement.default}.a"
-    end
+        lockfile_version
+  end
+
+  def bundler_requirement
+    return "#{Gem::Requirement.default}.a" unless bundler_version
+
+    bundler_gem_version = Gem::Version.new(bundler_version)
+
+    requirement = bundler_gem_version.approximate_recommendation
+
+    return requirement unless Gem::Version.new(Gem::VERSION) < Gem::Version.new("2.7.0")
+
+    requirement += ".a" if bundler_gem_version.prerelease?
+
+    requirement
   end
 
   def load_bundler!
     ENV["BUNDLE_GEMFILE"] ||= gemfile
 
-    # must dup string for RG < 1.8 compatibility
-    activate_bundler(bundler_version.dup)
+    activate_bundler
   end
 
-  def activate_bundler(bundler_version)
-    if Gem::Version.correct?(bundler_version) && Gem::Version.new(bundler_version).release < Gem::Version.new("2.0")
-      bundler_version = "< 2"
-    end
+  def activate_bundler
     gem_error = activation_error_handling do
-      gem "bundler", bundler_version
+      gem "bundler", bundler_requirement
     end
     return if gem_error.nil?
     require_error = activation_error_handling do
       require "bundler/version"
     end
-    return if require_error.nil? && Gem::Requirement.new(bundler_version).satisfied_by?(Gem::Version.new(Bundler::VERSION))
-    warn "Activating bundler (#{bundler_version}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_version}'`"
+    return if require_error.nil? && Gem::Requirement.new(bundler_requirement).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+    warn "Activating bundler (#{bundler_requirement}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_requirement}'`"
     exit 42
   end