Add support for SHA256

Library/Homebrew/formula.rb

@@ -54,8 +54,12 @@ class Formula
     @version=Pathname.new(@url).version unless @version
     validate_variable :version if @version
     @homepage=self.class.homepage unless @homepage
-    @md5=self.class.md5 unless @md5
-    @sha1=self.class.sha1 unless @sha1
+    CHECKSUM_TYPES.each do |type|
+      if !instance_variable_defined?("@#{type}")
+        class_value = self.class.send(type)
+        instance_variable_set("@#{type}", class_value) if class_value
+      end
+    end
   end
 
   # if the dir is there, but it's empty we consider it not installed
@@ -206,12 +210,15 @@ private
     end
   end
 
+  CHECKSUM_TYPES=[:md5, :sha1, :sha256].freeze
+
   def verify_download_integrity fn
     require 'digest'
-    type='MD5'
-    type='SHA1' if @sha1
-    supplied=eval "@#{type.downcase}"
-    hash=eval("Digest::#{type}").hexdigest(fn.read)
+    type=CHECKSUM_TYPES.detect { |type| instance_variable_defined?("@#{type}") }
+    type ||= :md5
+    supplied=instance_variable_get("@#{type}")
+    type=type.to_s.upcase
+    hash=Digest.const_get(type).hexdigest(fn.read)
 
     if supplied and not supplied.empty?
       raise "#{type} mismatch: #{hash}" unless supplied.upcase == hash.upcase
@@ -271,7 +278,8 @@ private
   end
 
   class <<self
-    attr_reader :url, :version, :homepage, :md5, :sha1, :head
+    attr_reader :url, :version, :homepage, :head
+    attr_reader *CHECKSUM_TYPES
   end
 end
 

Library/Homebrew/unittest.rb

@@ -296,6 +296,26 @@ class BeerTasting <Test::Unit::TestCase
     end
   end
 
+  def test_sha256
+    valid_sha256 = Class.new(TestBall) do
+      @sha256='ccbf5f44743b74add648c7e35e414076632fa3b24463d68d1f6afc5be77024f8'
+    end
+
+    assert_nothing_raised do
+      nostdout { valid_sha256.new.brew {} }
+    end
+  end
+
+  def test_badsha256
+    invalid_sha256 = Class.new(TestBall) do
+      @sha256='dcbf5f44743b74add648c7e35e414076632fa3b24463d68d1f6afc5be77024f8'
+    end
+
+    assert_raises RuntimeError do
+      nostdout { invalid_sha256.new.brew {} }
+    end
+  end
+  
   FOOBAR='foo-bar'
   def test_formula_funcs
     classname=Formula.class(FOOBAR)