Finished porting of save_png over to args classes

spec/args/save_batch_spec.rb

@@ -5,17 +5,47 @@ describe Squib::Args::SaveBatch do
   subject(:save_batch) {Squib::Args::SaveBatch.new}
 
   context 'dir' do
-
     it 'is created if not exists (and warns)' do
       opts = {dir: 'tocreate'}
       Dir.chdir(output_dir) do
         FileUtils.rm_rf('tocreate', secure: true)
         expect(Squib.logger).to receive(:warn).with("Dir 'tocreate' does not exist, creating it.").once
         save_batch.load! opts
-        expect(save_batch).to have_attributes({dir: 'tocreate'})
+        expect(save_batch).to have_attributes({dir: ['tocreate']})
         expect(Dir.exists? 'tocreate').to be true
       end
     end
-
   end
+
+  context 'rotate' do
+    it 'does nothing by default' do
+      opts = {}
+      save_batch.load! opts
+      expect(save_batch[0]).to have_attributes({rotate: false, angle: 0})
+    end
+
+    it 'rotates by pi/2 with true' do
+      opts = {rotate: true}
+      save_batch.load! opts
+      expect(save_batch[0]).to have_attributes({rotate: true, angle: Math::PI / 2})
+    end
+
+    it 'rotates by pi/2' do
+      opts = {rotate: :clockwise}
+      save_batch.load! opts
+      expect(save_batch[0]).to have_attributes({rotate: true, angle: Math::PI / 2})
+    end
+
+    it 'rotates by pi/2 with counterclockwise' do
+      opts = {rotate: :counterclockwise}
+      save_batch.load! opts
+      expect(save_batch[0]).to have_attributes({rotate: true, angle: 3 * Math::PI / 2})
+    end
+
+    it 'raises error on a number' do
+      opts = {rotate: 5.0}
+      expect { save_batch.load!(opts) }.to raise_error('invalid option to rotate: only [true, false, :clockwise, :counterclockwise]')
+    end
+  end
+
 end