initial work on ruby_version dsl

lib/bundler/cli.rb

@@ -617,6 +617,11 @@ def clean
       end
     end
 
+    desc "ruby", "Displays the ruby version specified"
+    def ruby
+      Bundler.ui.info Bundler.definition.ruby_version
+    end
+
   private
 
     def setup_cache_all

lib/bundler/definition.rb

@@ -5,7 +5,7 @@ module Bundler
   class Definition
     include GemHelpers
 
-    attr_reader :dependencies, :platforms, :sources
+    attr_reader :dependencies, :platforms, :sources, :ruby_version
 
     def self.build(gemfile, lockfile, unlock)
       unlock ||= {}
@@ -30,13 +30,14 @@ def self.build(gemfile, lockfile, unlock)
       specs, then we can try to resolve locally.
 =end
 
-    def initialize(lockfile, dependencies, sources, unlock)
+    def initialize(lockfile, dependencies, sources, unlock, ruby_version = "")
       @unlocking = unlock == true || !unlock.empty?
 
       @dependencies, @sources, @unlock = dependencies, sources, unlock
       @remote            = false
       @specs             = nil
       @lockfile_contents = ""
+      @ruby_version      = ruby_version
 
       if lockfile && File.exists?(lockfile)
         @lockfile_contents = Bundler.read_file(lockfile)

lib/bundler/dsl.rb

@@ -25,6 +25,7 @@ def initialize
       @groups          = []
       @platforms       = []
       @env             = nil
+      @ruby_version    = ""
     end
 
     def eval_gemfile(gemfile)
@@ -144,7 +145,7 @@ def git(uri, options = {}, source_options = {}, &blk)
 
     def to_definition(lockfile, unlock)
       @sources << @rubygems_source unless @sources.include?(@rubygems_source)
-      Definition.new(lockfile, @dependencies, @sources, unlock)
+      Definition.new(lockfile, @dependencies, @sources, unlock, @ruby_version)
     end
 
     def group(*args, &blk)
@@ -169,6 +170,16 @@ def env(name)
       @env = old
     end
 
+    def ruby_version(ruby_version, options = {})
+      raise GemfileError, "Please define :engine_version" if options[:engine] && options[:engine_version].nil?
+      raise GemfileError, "Please define :engine" if options[:engine_version] && options[:engine].nil?
+
+      engine         = options[:engine] || "ruby"
+      raise GemfileError, "ruby_version must match the :engine_version for MRI" if options[:engine] == "ruby" && options[:engine_version] && ruby_version != options[:engine_version]
+      engine_version = engine == "ruby" ? ruby_version : options[:engine_version]
+      @ruby_version  = "ruby #{ruby_version} (#{engine} #{engine_version})"
+    end
+
     def method_missing(name, *args)
       location = caller[0].split(':')[0..1].join(':')
       raise GemfileError, "Undefined local variable or method `#{name}' for Gemfile\n" \

spec/other/ruby_spec.rb

@@ -0,0 +1,94 @@
+require "spec_helper"
+
+describe "bundle ruby", :focused => true do
+  it "returns ruby version when explicit" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      ruby_version "1.9.3", :engine => 'ruby', :engine_version => '1.9.3'
+
+      gem "foo"
+    G
+
+    bundle "ruby"
+
+    out.should eq("ruby 1.9.3 (ruby 1.9.3)")
+  end
+
+  it "engine defaults to MRI" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      ruby_version "1.9.3"
+
+      gem "foo"
+    G
+
+    bundle "ruby"
+
+    out.should eq("ruby 1.9.3 (ruby 1.9.3)")
+  end
+
+  it "handles jruby" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      ruby_version "1.8.7", :engine => 'jruby', :engine_version => '1.6.5'
+
+      gem "foo"
+    G
+
+    bundle "ruby"
+
+    out.should eq("ruby 1.8.7 (jruby 1.6.5)")
+  end
+
+  it "handles rbx" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      ruby_version "1.8.7", :engine => 'rbx', :engine_version => '1.2.4'
+
+      gem "foo"
+    G
+
+    bundle "ruby"
+
+    out.should eq("ruby 1.8.7 (rbx 1.2.4)")
+  end
+
+  it "raises an error if engine is used but engine version is not" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      ruby_version "1.8.7", :engine => 'rbx'
+
+      gem "foo"
+    G
+
+    bundle "ruby", :exitstatus => true
+
+    exitstatus.should_not == 0
+  end
+
+  it "raises an error if engine_version is used but engine is not" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      ruby_version "1.8.7", :engine_version => '1.2.4'
+
+      gem "foo"
+    G
+
+    bundle "ruby", :exitstatus => true
+
+    exitstatus.should_not == 0
+  end
+
+  it "raises an error if engine version doesn't match ruby version for mri" do
+    gemfile <<-G
+      source "file://#{gem_repo1}"
+      ruby_version "1.8.7", :engine => 'ruby', :engine_version => '1.2.4'
+
+      gem "foo"
+    G
+
+    bundle "ruby", :exitstatus => true
+
+    exitstatus.should_not == 0
+  end
+end