New feature: File.DuplicateRowTo() duplicate row to specified row position.

DuplicateRowTo() is similar to DuplicateRow() but copies specified row not just after specified source row
but to any other specified position below or above source row.

Also I made minor modifications of tests: using filepath.Join() instead of direct unix-way paths strings
to avoid possible tests fails on other OS.

datavalidation_test.go

@@ -10,13 +10,14 @@
 package excelize
 
 import (
+	"path/filepath"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 )
 
 func TestDataValidation(t *testing.T) {
-	const resultFile = "./test/TestDataValidation.xlsx"
+	resultFile := filepath.Join("test", "TestDataValidation.xlsx")
 
 	xlsx := NewFile()
 
@@ -50,7 +51,7 @@ func TestDataValidation(t *testing.T) {
 }
 
 func TestDataValidationError(t *testing.T) {
-	const resultFile = "./test/TestDataValidationError.xlsx"
+	resultFile := filepath.Join("test", "TestDataValidationError.xlsx")
 
 	xlsx := NewFile()
 	xlsx.SetCellStr("Sheet1", "E1", "E1")

excelize.go

@@ -238,18 +238,16 @@ func (f *File) adjustRowDimensions(xlsx *xlsxWorksheet, rowIndex, offset int) {
 	}
 	for i, r := range xlsx.SheetData.Row {
 		if r.R >= rowIndex {
-			f.ajustSingleRowDimensions(&xlsx.SheetData.Row[i], offset)
+			f.ajustSingleRowDimensions(&xlsx.SheetData.Row[i], r.R+offset)
 		}
 	}
 }
 
-// ajustSingleRowDimensions provides a function to ajust single row
-// dimensions.
-func (f *File) ajustSingleRowDimensions(r *xlsxRow, offset int) {
-	r.R += offset
+// ajustSingleRowDimensions provides a function to ajust single row dimensions.
+func (f *File) ajustSingleRowDimensions(r *xlsxRow, row int) {
+	r.R = row
 	for i, col := range r.C {
-		row, _ := strconv.Atoi(strings.Map(intOnlyMapF, col.R))
-		r.C[i].R = string(strings.Map(letterOnlyMapF, col.R)) + strconv.Itoa(row+offset)
+		r.C[i].R = string(strings.Map(letterOnlyMapF, col.R)) + strconv.Itoa(r.R)
 	}
 }
 

go.mod

@@ -3,6 +3,5 @@ module github.com/360EntSecGroup-Skylar/excelize
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826
-	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/stretchr/testify v1.2.3-0.20181224173747-660f15d67dbb
+	github.com/stretchr/testify v1.3.0
 )

go.sum

+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826 h1:RWengNIwukTxcDr9M+97sNutRR1RKhG96O6jWumTTnw=
 github.com/mohae/deepcopy v0.0.0-20170929034955-c48cc78d4826/go.mod h1:TaXosZuwdSHYgviHp1DAtfrULt5eUgsSMsZf+YrPgl8=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
-github.com/stretchr/testify v1.2.3-0.20181224173747-660f15d67dbb h1:cRItZejS4Ok67vfCdrbGIaqk86wmtQNOjVD7jSyS2aw=
-github.com/stretchr/testify v1.2.3-0.20181224173747-660f15d67dbb/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=

rows.go

@@ -376,38 +376,55 @@ func (f *File) InsertRow(sheet string, row int) {
 //    xlsx.DuplicateRow("Sheet1", 2)
 //
 func (f *File) DuplicateRow(sheet string, row int) {
-	if row < 0 {
+	f.DuplicateRowTo(sheet, row, row+1)
+}
+
+// DuplicateRowTo inserts a copy of specified row at specified row position
+// movig down exists rows aftet target position
+//
+//    xlsx.DuplicateRowTo("Sheet1", 2, 7)
+//
+func (f *File) DuplicateRowTo(sheet string, row, row2 int) {
+	if row <= 0 || row2 <= 0 || row == row2 {
 		return
 	}
-	row2 := row + 1
-	f.adjustHelper(sheet, -1, row2, 1)
 
-	xlsx := f.workSheetReader(sheet)
-	idx := -1
-	idx2 := -1
+	ws := f.workSheetReader(sheet)
 
-	for i, r := range xlsx.SheetData.Row {
+	var ok bool
+	var rowCopy xlsxRow
+
+	for i, r := range ws.SheetData.Row {
 		if r.R == row {
-			idx = i
-		} else if r.R == row2 {
-			idx2 = i
-		}
-		if idx != -1 && idx2 != -1 {
+			rowCopy = ws.SheetData.Row[i]
+			ok = true
 			break
 		}
 	}
+	if !ok {
+		return
+	}
 
-	if idx == -1 || (idx2 == -1 && len(xlsx.SheetData.Row) >= row2) {
+	f.adjustHelper(sheet, -1, row2, 1)
+
+	idx2 := -1
+	for i, r := range ws.SheetData.Row {
+		if r.R == row2 {
+			idx2 = i
+			break
+		}
+	}
+	if idx2 == -1 && len(ws.SheetData.Row) >= row2 {
 		return
 	}
-	rowData := xlsx.SheetData.Row[idx]
-	cols := make([]xlsxC, 0, len(rowData.C))
-	rowData.C = append(cols, rowData.C...)
-	f.ajustSingleRowDimensions(&rowData, 1)
+
+	rowCopy.C = append(make([]xlsxC, 0, len(rowCopy.C)), rowCopy.C...)
+	f.ajustSingleRowDimensions(&rowCopy, row2)
+
 	if idx2 != -1 {
-		xlsx.SheetData.Row[idx2] = rowData
+		ws.SheetData.Row[idx2] = rowCopy
 	} else {
-		xlsx.SheetData.Row = append(xlsx.SheetData.Row, rowData)
+		ws.SheetData.Row = append(ws.SheetData.Row, rowCopy)
 	}
 }
 
@@ -446,7 +463,7 @@ func checkRow(xlsx *xlsxWorksheet) {
 			if lenCol < endCol {
 				oldRow := xlsx.SheetData.Row[k].C
 				xlsx.SheetData.Row[k].C = xlsx.SheetData.Row[k].C[:0]
-				tmp := []xlsxC{}
+				var tmp []xlsxC
 				for i := 0; i < endCol; i++ {
 					buffer.WriteString(ToAlphaString(i))
 					buffer.WriteString(strconv.Itoa(endRow))