New patch implementation and DSL

This commit introduces a new patch implementation that supports
checksums and caching.

Patches are declared in blocks:

  patch do
    url ...
    sha1 ...
  end

A strip level of -p1 is assumed. It can be overridden using a symbol
argument:

  patch :p0 do
    url ...
    sha1 ...
  end

Patches can be declared in stable, devel, and head blocks. This form is
preferred over using conditionals.

  stable do
    # ...

    patch do
      url ...
      sha1 ...
    end
  end

Embedded (__END__) patches are declared like so:

  patch :DATA
  patch :p0, :DATA

Patches can also be embedded by passing a string. This makes it possible
to provide multiple embedded patches while making only some of them
conditional.

  patch :p0, "..."

2 files changed, 58 insertions, 0 deletions

diff --git a/Library/Homebrew/test/test_patch.rb b/Library/Homebrew/test/test_patch.rb
new file mode 100644
index 000000000..1cc1ac7af
--- /dev/null
+++ b/Library/Homebrew/test/test_patch.rb
@@ -0,0 +1,52 @@
+require 'testing_env'
+require 'patch'
+
+class PatchTests < Test::Unit::TestCase
+  def test_create_simple
+    patch = Patch.create(:p2)
+    assert_kind_of ExternalPatch, patch
+    assert patch.external?
+    assert_equal :p2, patch.strip
+  end
+
+  def test_create_io
+    patch = Patch.create(:p0, StringIO.new("foo"))
+    assert_kind_of IOPatch, patch
+    assert !patch.external?
+    assert_equal :p0, patch.strip
+  end
+
+  def test_create_io_without_strip
+    patch = Patch.create(StringIO.new("foo"))
+    assert_kind_of IOPatch, patch
+    assert_equal :p1, patch.strip
+  end
+
+  def test_create_string
+    patch = Patch.create(:p0, "foo")
+    assert_kind_of IOPatch, patch
+    assert_equal :p0, patch.strip
+  end
+
+  def test_create_string_without_strip
+    patch = Patch.create("foo")
+    assert_kind_of IOPatch, patch
+    assert_equal :p1, patch.strip
+  end
+
+  def test_create_DATA
+    patch = Patch.create(:p0, :DATA)
+    assert_kind_of IOPatch, patch
+    assert_equal :p0, patch.strip
+  end
+
+  def test_create_DATA_without_strip
+    patch = Patch.create(:DATA)
+    assert_kind_of IOPatch, patch
+    assert_equal :p1, patch.strip
+  end
+
+  def test_raises_for_unknown_values
+    assert_raises(ArgumentError) { Patch.create(Object.new) }
+  end
+end
diff --git a/Library/Homebrew/test/test_software_spec.rb b/Library/Homebrew/test/test_software_spec.rb
index c35294320..7c9fb8720 100644
--- a/Library/Homebrew/test/test_software_spec.rb
+++ b/Library/Homebrew/test/test_software_spec.rb
@@ -80,6 +80,12 @@ class SoftwareSpecTests < Test::Unit::TestCase
     @spec.depends_on('foo' => :optional)
     assert_equal 'blah', @spec.build.first.description
   end
+
+  def test_patch
+    @spec.patch :p1, :DATA
+    assert_equal 1, @spec.patches.length
+    assert_equal :p1, @spec.patches.first.strip
+  end
 end
 
 class HeadSoftwareSpecTests < Test::Unit::TestCase