Change to allow cncat to merge 3 or more CSV files

README.md

@@ -238,18 +238,17 @@ Check the column names and concat them into the same column.
 ### Usage
 
 ```
-csvt concat -1 INPUT1 -2 INPUT2 -o OUTPUT
+csvt concat -i INPUT1 -i INPUT2 [-i INPUT3 ...] -o OUTPUT
 ```
 
 ```
 Usage:
   csvt concat [flags]
 
 Flags:
-  -1, --first string    First CSV file path.
-  -2, --second string   Second CSV file path.
-  -o, --output string   Output CSV file path.
-  -h, --help            help for concat
+  -i, --input stringArray   Input CSV files path.
+  -o, --output string       Output CSV file path.
+  -h, --help                help for concat
 ```
 
 ### Example
@@ -273,7 +272,7 @@ name4,4
 Concat `input1.csv` and `input2.csv`.
 
 ```
-$ csvt concat -1 input1.csv -2 input2.csv -o output.csv
+$ csvt concat -i input1.csv -i input2.csv -o output.csv
 ```
 
 The contents of the created `output.csv`.

cmd/common_test.go

@@ -1,7 +1,6 @@
 package cmd
 
 import (
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -60,7 +59,7 @@ func joinRows(rows ...string) string {
 
 func readDir(t *testing.T, dir string) map[string][]byte {
 
-	files, err := ioutil.ReadDir(dir)
+	files, err := os.ReadDir(dir)
 	if err != nil {
 		t.Fatal("read dir failed\n", err)
 	}

cmd/concat.go

@@ -21,91 +21,68 @@ func newConcatCmd() *cobra.Command {
 				return err
 			}
 
-			firstPath, _ := cmd.Flags().GetString("first")
-			secondPath, _ := cmd.Flags().GetString("second")
+			inputPaths, _ := cmd.Flags().GetStringArray("input")
 			outputPath, _ := cmd.Flags().GetString("output")
 
 			// 引数の解析に成功した時点で、エラーが起きてもUsageは表示しない
 			cmd.SilenceUsage = true
 
-			return runConcat(format, firstPath, secondPath, outputPath)
+			return runConcat(format, inputPaths, outputPath)
 		},
 	}
 
-	concatCmd.Flags().StringP("first", "1", "", "First CSV file path.")
-	concatCmd.MarkFlagRequired("first")
-	concatCmd.Flags().StringP("second", "2", "", "Second CSV file path.")
-	concatCmd.MarkFlagRequired("second")
+	concatCmd.Flags().StringArrayP("input", "i", []string{}, "Input CSV files path.")
+	concatCmd.MarkFlagRequired("input")
 	concatCmd.Flags().StringP("output", "o", "", "Output CSV file path.")
 	concatCmd.MarkFlagRequired("output")
 
 	return concatCmd
 }
 
-func runConcat(format csv.Format, firstPath string, secondPath string, outputPath string) error {
+func runConcat(format csv.Format, inputPaths []string, outputPath string) error {
 
-	firstReader, firstClose, err := setupInput(firstPath, format)
-	if err != nil {
-		return err
-	}
-	defer firstClose()
+	readers := []csv.CsvReader{}
 
-	secondReader, secondClose, err := setupInput(secondPath, format)
-	if err != nil {
-		return err
+	for _, inputPath := range inputPaths {
+		reader, inputClose, err := setupInput(inputPath, format)
+		if err != nil {
+			return err
+		}
+		defer inputClose()
+
+		readers = append(readers, reader)
 	}
-	defer secondClose()
 
 	writer, outputClose, err := setupOutput(outputPath, format)
 	if err != nil {
 		return err
 	}
 	defer outputClose()
 
-	err = concat(firstReader, secondReader, writer)
+	err = concat(readers, writer)
 	if err != nil {
 		return err
 	}
 
 	return writer.Flush()
 }
 
-func concat(first csv.CsvReader, second csv.CsvReader, writer csv.CsvWriter) error {
+func concat(readers []csv.CsvReader, writer csv.CsvWriter) error {
 
-	firstColumnNames, err := first.Read()
+	firstReader := readers[0]
+	firstColumnNames, err := firstReader.Read()
 	if err != nil {
 		return errors.Wrap(err, "failed to read the first CSV file")
 	}
 
-	secondColumnNames, err := second.Read()
-	if err != nil {
-		return errors.Wrap(err, "failed to read the second CSV file")
-	}
-
-	if len(firstColumnNames) != len(secondColumnNames) {
-		return fmt.Errorf("number of columns does not match")
-	}
-
-	// 1つ目のCSVのカラム名と2つ目のCSVのカラム名のマッピングを作成
-	secondColumnIndexes := []int{}
-	for _, firstColumnName := range firstColumnNames {
-
-		secondColumnIndex, err := getTargetColumnIndex(secondColumnNames, firstColumnName)
-		if err != nil {
-			return errors.Wrap(err, "no column corresponding to the second CSV file")
-		}
-
-		secondColumnIndexes = append(secondColumnIndexes, secondColumnIndex)
-	}
-
 	// 1つ目の書き込み
 	err = writer.Write(firstColumnNames)
 	if err != nil {
 		return err
 	}
 
 	for {
-		row, err := first.Read()
+		row, err := firstReader.Read()
 		if err == io.EOF {
 			break
 		}
@@ -119,25 +96,51 @@ func concat(first csv.CsvReader, second csv.CsvReader, writer csv.CsvWriter) err
 		}
 	}
 
-	// 2つ目の書き込み
-	for {
-		row, err := second.Read()
-		if err == io.EOF {
-			break
-		}
+	// 2つ目以降
+	count := 1
+	for _, reader := range readers[1:] {
+		count++
+
+		columnNames, err := reader.Read()
 		if err != nil {
-			return errors.Wrap(err, "failed to read the second CSV file")
+			return errors.Wrapf(err, "failed to read CSV file (%d)", count)
 		}
 
-		// 1つ目のCSVに合わせてカラム入れ替え
-		swapedRow := []string{}
-		for _, secondColumnIndex := range secondColumnIndexes {
-			swapedRow = append(swapedRow, row[secondColumnIndex])
+		if len(firstColumnNames) != len(columnNames) {
+			return fmt.Errorf("number of columns does not match (%d)", count)
 		}
 
-		err = writer.Write(swapedRow)
-		if err != nil {
-			return err
+		// 1つ目のCSVのカラム名とのカラム名のマッピングを作成
+		columnIndexes := []int{}
+		for _, firstColumnName := range firstColumnNames {
+
+			columnIndex, err := getTargetColumnIndex(columnNames, firstColumnName)
+			if err != nil {
+				return errors.Wrapf(err, "no column corresponding in CSV file (%d)", count)
+			}
+
+			columnIndexes = append(columnIndexes, columnIndex)
+		}
+
+		for {
+			row, err := reader.Read()
+			if err == io.EOF {
+				break
+			}
+			if err != nil {
+				return errors.Wrapf(err, "failed to read CSV file (%d)", count)
+			}
+
+			// 1つ目のCSVに合わせてカラム入れ替え
+			swapedRow := []string{}
+			for _, columnIndex := range columnIndexes {
+				swapedRow = append(swapedRow, row[columnIndex])
+			}
+
+			err = writer.Write(swapedRow)
+			if err != nil {
+				return err
+			}
 		}
 	}
 

cmd/concat_test.go

@@ -28,8 +28,8 @@ func TestConcatCmd(t *testing.T) {
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2,
+		"-i", fi1,
+		"-i", fi2,
 		"-o", fo,
 	})
 
@@ -70,14 +70,23 @@ b2,b3,4
 	fi2 := createTempFile(t, s2)
 	defer os.Remove(fi2)
 
+	s3 := `col3,col1,col2
+-3,5,-2
++3,6,+2
+`
+
+	fi3 := createTempFile(t, s3)
+	defer os.Remove(fi3)
+
 	fo := createTempFile(t, "")
 	defer os.Remove(fo)
 
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2,
+		"-i", fi1,
+		"-i", fi2,
+		"-i", fi3,
 		"-o", fo,
 	})
 
@@ -94,6 +103,8 @@ b2,b3,4
 		"2,y2,y3",
 		"3,a2,a3",
 		"4,b2,b3",
+		"5,-2,-3",
+		"6,+2,+3",
 	)
 
 	if result != expect {
@@ -121,8 +132,8 @@ a	b
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2,
+		"-i", fi1,
+		"-i", fi2,
 		"-o", fo,
 		"--delim", `\t`,
 	})
@@ -159,8 +170,8 @@ func TestConcatCmd_invalidFormat(t *testing.T) {
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2,
+		"-i", fi1,
+		"-i", fi2,
 		"-o", fo,
 		"--delim", `\t\t`,
 	})
@@ -191,13 +202,13 @@ func TestConcatCmd_columnCountUnmatch(t *testing.T) {
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2,
+		"-i", fi1,
+		"-i", fi2,
 		"-o", fo,
 	})
 
 	err := rootCmd.Execute()
-	if err == nil || err.Error() != "number of columns does not match" {
+	if err == nil || err.Error() != "number of columns does not match (2)" {
 		t.Fatal("failed test\n", err)
 	}
 }
@@ -222,13 +233,13 @@ func TestConcatCmd_columnNotFound(t *testing.T) {
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2,
+		"-i", fi1,
+		"-i", fi2,
 		"-o", fo,
 	})
 
 	err := rootCmd.Execute()
-	if err == nil || err.Error() != "no column corresponding to the second CSV file: missing col2 in the CSV file" {
+	if err == nil || err.Error() != "no column corresponding in CSV file (2): missing col2 in the CSV file" {
 		t.Fatal("failed test\n", err)
 	}
 }
@@ -250,8 +261,8 @@ func TestConcatCmd_firstEmpty(t *testing.T) {
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2,
+		"-i", fi1,
+		"-i", fi2,
 		"-o", fo,
 	})
 
@@ -279,13 +290,13 @@ func TestConcatCmd_secondEmpty(t *testing.T) {
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2,
+		"-i", fi1,
+		"-i", fi2,
 		"-o", fo,
 	})
 
 	err := rootCmd.Execute()
-	if err == nil || err.Error() != "failed to read the second CSV file: EOF" {
+	if err == nil || err.Error() != "failed to read CSV file (2): EOF" {
 		t.Fatal("failed test\n", err)
 	}
 }
@@ -304,8 +315,8 @@ func TestConcatCmd_firstFileNotFound(t *testing.T) {
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1 + "____", // 存在しないファイル
-		"-2", fi2,
+		"-i", fi1 + "____", // 存在しないファイル
+		"-i", fi2,
 		"-o", fo,
 	})
 
@@ -334,8 +345,8 @@ func TestConcatCmd_secondFileNotFound(t *testing.T) {
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2 + "____", // 存在しないファイル
+		"-i", fi1,
+		"-i", fi2 + "____", // 存在しないファイル
 		"-o", fo,
 	})
 
@@ -364,8 +375,8 @@ func TestConcatCmd_outputFileNotFound(t *testing.T) {
 	rootCmd := newRootCmd()
 	rootCmd.SetArgs([]string{
 		"concat",
-		"-1", fi1,
-		"-2", fi2,
+		"-i", fi1,
+		"-i", fi2,
 		"-o", fo + "/aa", // 存在しないフォルダ
 	})