Merge pull request EricR#4 from musicglue/graphics_magick

add support for graphics magick with some DCI (guyboertje)

lib/gm_support.rb

@@ -0,0 +1,15 @@
+module GmSupport
+  def prefix command
+    "gm #{command}"
+  end
+end
+
+class Sorcery
+  class << self
+    def gm file
+      instance = new(file)
+      instance.extend GmSupport
+      instance
+    end
+  end
+end

lib/image_sorcery.rb

@@ -1,4 +1,5 @@
 require 'subexec'
+require 'gm_support'
 
 class Sorcery
   def initialize(file)
@@ -53,6 +54,7 @@ def dimensions
   private
 
   def convert_to_command(tokens)
+    tokens[0] = prefix(tokens[0]) if respond_to? :prefix
     tokens.flatten.join("")
   end
 

spec/image_sorcery_gm_spec.rb

@@ -0,0 +1,32 @@
+require 'fileutils'
+require 'image_sorcery'
+
+describe "Image Sorcery" do
+  before :each do
+    FileUtils.copy "./spec/fixtures/dog.jpeg", "./spec/fixtures/dog-2.jpeg"
+    @image = Sorcery.gm("./spec/fixtures/dog-2.jpeg") # Who doesn't love dogs?
+  end
+  describe "getting the dimensions of an image" do
+    it "returns a hash of dimensions" do
+      @image.dimensions.should == {:x => "160", :y => "120"}
+    end
+  end
+  describe "manipulating an image" do
+    it "resizes an image" do
+      original_dimensions = @image.dimensions
+      @image.manipulate!(:resize => "50%")
+      @image.dimensions.map {|k,v| v.to_i}.should == original_dimensions.map {|k,v| v.to_i/2}
+    end
+  end
+  describe "converting an image" do
+    it "writes the new image out to a file" do
+      @image.convert("new_image.png")
+      File.exists?("new_image.png").should be_true
+    end
+  end
+  describe "identifying an image" do
+    it "returns a list of layers" do
+      @image.identify.should include "JPEG 160x120"
+    end
+  end
+end