Add missing multiplier option for number fields. (#642)

lib/administrate/field/number.rb

@@ -7,7 +7,7 @@ def to_s
         if data.nil?
           "-"
         else
-          format_string % data
+          format_string % value
         end
       end
 
@@ -24,6 +24,10 @@ def prefix
       def decimals
         options.fetch(:decimals, 0)
       end
+
+      def value
+        data * options.fetch(:multiplier, 1)
+      end
     end
   end
 end

spec/lib/fields/number_spec.rb

@@ -53,6 +53,16 @@
       end
     end
 
+    context "with `multiplier` option" do
+      it "multiples the number by the given multiplier" do
+        hundredth = number_with_options(100, multiplier: 0.01)
+        ten = number_with_options(100, multiplier: 10)
+
+        expect(hundredth.to_s).to eq("1")
+        expect(ten.to_s).to eq("1000")
+      end
+    end
+
     context "when data is nil" do
       it "returns a dash" do
         number = Administrate::Field::Number.new(:number, nil, :page)