Convert save_sheet and save_pdf to args classes

spec/args/sheet_spec.rb

@@ -13,4 +13,46 @@ describe Squib::Args::Sheet do
 
   end
 
+  context 'rows and colums' do
+    subject(:sheet) { Squib::Args::Sheet.new({}, {}, 4) }
+
+    it 'does nothing on a perfect fit' do
+      opts = { columns: 2, rows: 2 }
+      sheet.load! opts
+      expect(sheet).to have_attributes(columns: 2, rows: 2)
+    end
+
+    it 'keeps both if specified' do
+      opts = { columns: 1, rows: 1 }
+      sheet.load! opts
+      expect(sheet).to have_attributes(columns: 1, rows: 1)
+    end
+
+    it 'computes properly on non-integer' do
+      opts = {columns: 1, rows: :infinite}
+      sheet.load! opts
+      expect(sheet).to have_attributes( columns: 1, rows: 4 )
+    end
+
+    it 'computes properly on unspecified rows' do
+      opts = {columns: 1}
+      sheet.load! opts
+      expect(sheet).to have_attributes( columns: 1, rows: 4 )
+    end
+
+    it 'computes properly on unspecified, too-big column' do
+      opts = {}
+      sheet.load! opts
+      expect(sheet).to have_attributes( columns: 5, rows: 1 )
+    end
+
+    it 'fails on a non-integer column' do
+      opts = {columns: :infinite}
+      expect { sheet.load!(opts) }.to raise_error('columns must be an integer')
+    end
+
+
+
+  end
+
 end