anchor.diff:              applyNumberFormat = numberFormat && 1 || void 0,
               borderId = borderId,
               fillId =  fillId,
  -            fontId = locals.fontRefs[style.font],
  +            fontId = fontId,
               numFmtId = numberFormat,
               xfId=0
             )
  
positive.code:       xf(borderId="0" fillId="0" fontId="0" numFmtId="0")/
      cellXfs(count=cellStyles.length)
        each style, t in cellStyles
          - var fillId = ('fill' in style && style.fill) || 0
          - var borderId = ('border' in style && style.border) || 0
          - var numberFormat = ('numberFormat' in style && (style.numberFormat + 200)) || 0
          if Object.keys(style).length === 1
            xf/
          else
            xf(
  
negative.code:             gradientFill&attributes()
      borders(count=borders.length)
        each border, r in borders
          if !border || Object.keys(border).length === 1
            border/
          else
            border
  