diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index 3d3c23ec37..a150800ba5 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -15,9 +15,9 @@ class Formula
   attr_reader :name, :path, :homepage, :downloader
   attr_reader :stable, :bottle, :devel, :head, :active_spec
 
-  # The build folder, usually in /tmp.
-  # Will only be non-nil during the stage method.
-  attr_reader :buildpath
+  # The current working directory during builds and tests.
+  # Will only be non-nil inside #stage and #test.
+  attr_reader :buildpath, :testpath
 
   # Homebrew determines the name
   def initialize name='__UNKNOWN__', path=nil
@@ -586,6 +586,16 @@ public
     @active_spec.verify_download_integrity(fn)
   end
 
+  def test
+    ret = nil
+    mktemp do
+      @testpath = Pathname.pwd
+      ret = instance_eval(&self.class.test)
+      @testpath = nil
+    end
+    ret
+  end
+
 private
 
   def stage
@@ -777,6 +787,11 @@ private
         CompilerFailure.new(compiler)
       end
     end
+
+    def test &block
+      return @test unless block_given?
+      @test = block
+    end
   end
 end