1 files changed, 33 insertions, 0 deletions
diff --git a/Library/Homebrew/requirements/ruby_requirement.rb b/Library/Homebrew/requirements/ruby_requirement.rb
new file mode 100644
index 000000000..cb723df9b
--- /dev/null
+++ b/Library/Homebrew/requirements/ruby_requirement.rb
@@ -0,0 +1,33 @@
+class RubyRequirement < Requirement
+  fatal true
+  #default_formula "ruby"
+
+  def initialize(tags)
+    @version = tags.shift if /(\d\.)+\d/ === tags.first
+    raise "RubyRequirement requires a version!" unless @version
+    super
+  end
+
+  satisfy :build_env => false do
+    next unless which "ruby"
+    version = /\d\.\d/.match `ruby --version 2>&1`
+    next unless version
+    Version.new(version.to_s) >= Version.new(@version)
+  end
+
+  env do
+    ENV.prepend_path "PATH", which("ruby").dirname
+  end
+
+  def message
+    version_string = " #{@version}" if @version
+
+    s = "Ruby#{version_string} is required to install this formula."
+    s += super
+    s
+  end
+
+  def inspect
+    "#<#{self.class.name}: #{name.inspect} #{tags.inspect} version=#{@version.inspect}>"
+  end
+end