Proper validation of Formula.name and version

Library/Homebrew/formula.rb

@@ -32,14 +32,14 @@ end
 # Derive and define at least @url, see Library/Formula for examples
 class Formula
   # Homebrew determines the name
-  def initialize name=nil
+  def initialize name='__UNKNOWN__'
     @url=self.class.url unless @url
     raise if @url.nil?
     @name=name
-    raise if @name =~ /\s/
+    validate_variable :name
     @version=self.class.version unless @version
     @version=Pathname.new(@url).version unless @version
-    raise if @version =~ /\s/
+    validate_variable :version if @version
     @homepage=self.class.homepage unless @homepage
     @md5=self.class.md5 unless @md5
     @sha1=self.class.sha1 unless @sha1
@@ -53,8 +53,8 @@ class Formula
   end
 
   def prefix
-    raise "Invalid @name" if @name.nil? or @name.empty?
-    raise "Invalid @version" if @version.nil? or @version.empty?
+    validate_variable :name
+    validate_variable :version
     HOMEBREW_CELLAR+@name+@version
   end
 
@@ -100,6 +100,9 @@ class Formula
 
   # yields self with current working directory set to the uncompressed tarball
   def brew
+    validate_variable :name
+    validate_variable :version
+    
     stage do
       begin
         patch
@@ -238,6 +241,11 @@ private
     end
   end
 
+  def validate_variable name
+    v=eval("@#{name}")
+    raise "Invalid @#{name}" if v.nil? or v.empty? or v =~ /\s/
+  end
+
   def method_added method
     raise 'You cannot override Formula.brew' if method == 'brew'
   end

Library/Homebrew/unittest.rb

@@ -281,10 +281,10 @@ class BeerTasting <Test::Unit::TestCase
   end
   
   def test_abstract_formula
-    f=MostlyAbstractFormula.new ''
-    assert_equal '', f.name
+    f=MostlyAbstractFormula.new
+    assert_equal '__UNKNOWN__', f.name
     assert_raises(RuntimeError) { f.prefix }
-    nostdout { assert_raises(ExecutionError) { f.brew } }
+    nostdout { assert_raises(RuntimeError) { f.brew } }
   end
 
   def test_zip