         diff = @choroplethMap.calculateDifference(@oldSnippetModel)
         expect(diff[3].properties[2]).to.eql
           label: 'quantize steps'
+          key: 'quantizeSteps'
           difference:
             type: 'change'
             previous: 3

        diff = @choroplethMap.calculateDifference(@oldSnippetModel)
        expect(diff[3].properties[0]).to.eql
          label: 'value property'
          difference: undefined
          info: '(value)'


        diff = @choroplethMap.calculateDifference(@oldSnippetModel)
        expect(diff[0].properties[1]).to.eql(
          label: 'projection'
          key: 'projection'
          difference:
            type: 'change'
            previous: 'mercator'
