Merge pull request #435 from rentiansheng/fix_col_empty

fix cols emtpy bug

file_test.go

@@ -840,8 +840,7 @@ func (l *FileSuite) TestMarshalFile(c *C) {
 	// For now we only allow simple string data in the
 	// spreadsheet.  Style support will follow.
 	expectedStyles := `<?xml version="1.0" encoding="UTF-8"?>
-<styleSheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"><fonts count="1"><font><sz val="12"/><name val="Verdana"/><family val="0"/><charset val="0"/></font></fonts><fills count="2"><fill><patternFill patternType="none"><fgColor rgb="FFFFFFFF"/><bgColor rgb="00000000"/></patternFill></fill><fill><patternFill patternType="lightGray"/></fill></fills><borders count="1"><border><left style="none"></left><right style="none"></right><top style="none"></top><bottom style="none"></bottom></border></borders><cellXfs count="2"><xf applyAlignment="0" applyBorder="0" applyFont="0" applyFill="0" applyNumberFormat="0" applyProtection="0" borderId="0" fillId="0" fontId="0" numFmtId="0"><alignment horizontal="general" indent="0" shrinkToFit="0" textRotation="0" vertical="bottom" wrapText="0"/></xf><xf applyAlignment="0" applyBorder="0" applyFont="0" applyFill="0" applyNumberFormat="0" applyProtection="0" borderId="0" fillId="0" fontId="0" numFmtId="0"><alignment horizontal="general" indent="0" shrinkToFit="0" textRotation="0" vertical="bottom" wrapText="0"/></xf></cellXfs></styleSheet>`
-
+<styleSheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"><fonts count="1"><font><sz val="12"/><name val="Verdana"/><family val="0"/><charset val="0"/></font></fonts><fills count="2"><fill><patternFill patternType="none"/></fill><fill><patternFill patternType="lightGray"/></fill></fills><borders count="1"><border><left style="none"></left><right style="none"></right><top style="none"></top><bottom style="none"></bottom></border></borders><cellXfs count="2"><xf applyAlignment="0" applyBorder="0" applyFont="0" applyFill="0" applyNumberFormat="0" applyProtection="0" borderId="0" fillId="0" fontId="0" numFmtId="0"><alignment horizontal="general" indent="0" shrinkToFit="0" textRotation="0" vertical="bottom" wrapText="0"/></xf><xf applyAlignment="0" applyBorder="0" applyFont="0" applyFill="0" applyNumberFormat="0" applyProtection="0" borderId="0" fillId="0" fontId="0" numFmtId="0"><alignment horizontal="general" indent="0" shrinkToFit="0" textRotation="0" vertical="bottom" wrapText="0"/></xf></cellXfs></styleSheet>`
 	c.Assert(parts["xl/styles.xml"], Equals, expectedStyles)
 }
 

style.go

@@ -164,7 +164,7 @@ func DefaultFont() *Font {
 }
 
 func DefaultFill() *Fill {
-	return NewFill("none", "FFFFFFFF", "00000000")
+	return NewFill("none", "", "")
 
 }