Implement Resources

Closes Homebrew/homebrew#20212.

1 files changed, 29 insertions, 0 deletions

diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index 15561b100..0ccf9292c 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -1,3 +1,4 @@
+require 'resource'
 require 'download_strategy'
 require 'dependency_collector'
 require 'formula_support'
@@ -56,6 +57,11 @@ class Formula
     end
 
     @pin = FormulaPin.new(self)
+
+    @resources = self.class.resources
+    @resources.each_value do |r|
+      r.set_owner name
+    end
   end
 
   def set_spec(name)
@@ -91,6 +97,16 @@ class Formula
   def version;  active_spec.version; end
   def mirrors;  active_spec.mirrors; end
 
+  def resource(name)
+    res = @resources[name]
+    raise ResourceMissingError.new(@name, name) if res.nil?
+    res
+  end
+
+  def resources
+    @resources.values
+  end
+
   # if the dir is there, but it's empty we consider it not installed
   def installed?
     (dir = installed_prefix).directory? && dir.children.length > 0
@@ -694,6 +710,19 @@ class Formula
       @stable.mirror(val)
     end
 
+    # Hold any resources defined by this formula
+    def resources
+      @resources ||= Hash.new
+    end
+
+    # Define a named resource using a SoftwareSpec style block
+    def resource res_name, &block
+      raise DuplicateResourceError.new(res_name) if resources.has_key?(res_name)
+      spec = SoftwareSpec.new
+      spec.instance_eval(&block)
+      resources[res_name] = Resource.new(res_name, spec)
+    end
+
     def dependencies
       @dependencies ||= DependencyCollector.new
     end