Add labels option for single file

cmd/tgcom/main.go

@@ -1,66 +1,87 @@
-package main
-
-import (
-	"flag"
-	"fmt"
-	"strings"
-
-	"github.com/dyne/tgcom/internal/comment"
-	"github.com/dyne/tgcom/internal/file"
-)
-
-func main() {
-	fileFlag := flag.String("file", "", "The file to process")
-	lineFlag := flag.String("line", "", "The line number or range to modify (e.g., 4 or 10-20)")
-	actionFlag := flag.String("action", "", "can be comment, uncomment or toggle")
-	dryRunFlag := flag.Bool("dry-run", false, "Perform a dry run without modifying the files")
-
-	flag.Parse()
-
-	filename := *fileFlag
-	lineStr := *lineFlag
-	action := *actionFlag
-	dryRun := *dryRunFlag
-	var modFunc func(string, string) string
-
-	switch action {
-	case "comment":
-		modFunc = comment.Comment
-	case "uncomment":
-		modFunc = comment.Uncomment
-	case "toggle":
-		modFunc = comment.ToggleComments
-	case "":
-		// If no action provided, assume toggle
-		modFunc = comment.ToggleComments
-	default:
-		fmt.Println("Invalid action. Please provide 'comment', 'uncomment', or 'toggle'.")
-		flag.PrintDefaults()
-		return
-	}
-
-	if filename == "" {
-		fmt.Println("Please provide a filename to process.")
-		flag.PrintDefaults()
-		return
-	}
-
-	if strings.Contains(filename, ",") {
-		if err := file.ProcessMultipleFiles(filename, dryRun); err != nil {
-			fmt.Println("Error processing files:", err)
-		}
-	} else {
-		if strings.Contains(filename, ":") {
-			parts := strings.Split(filename, ":")
-			if len(parts) != 2 {
-				fmt.Println("Invalid syntax format. Use '<filename>:<lines>'")
-				return
-			}
-			filename = parts[0]
-			lineStr = parts[1]
-		}
-		if err := file.ProcessSingleFile(filename, lineStr, modFunc, dryRun); err != nil {
-			fmt.Println("Error processing file:", err)
-		}
-	}
-}
+package main
+
+import (
+	"flag"
+	"fmt"
+	"strings"
+
+	"github.com/dyne/tgcom/internal/comment"
+	"github.com/dyne/tgcom/internal/file"
+)
+
+func main() {
+	fileFlag := flag.String("file", "", "The file to process")
+	lineFlag := flag.String("line", "", "The line number or range to modify (e.g., 4 or 10-20)")
+	startLabelFlag := flag.String("start-label", "", "The start label for a section")
+	endLabelFlag := flag.String("end-label", "", "The end label for a section")
+	actionFlag := flag.String("action", "", "can be comment, uncomment or toggle")
+	dryRunFlag := flag.Bool("dry-run", false, "Perform a dry run without modifying the files")
+
+	flag.Parse()
+
+	filename := *fileFlag
+	lineStr := *lineFlag
+	startLabel := *startLabelFlag
+	endLabel := *endLabelFlag
+	action := *actionFlag
+	dryRun := *dryRunFlag
+	var modFunc func(string, string) string
+
+	switch action {
+	case "comment":
+		modFunc = comment.Comment
+	case "uncomment":
+		modFunc = comment.Uncomment
+	case "toggle":
+		modFunc = comment.ToggleComments
+	case "":
+		// If no action provided, assume toggle
+		modFunc = comment.ToggleComments
+	default:
+		fmt.Println("Invalid action. Please provide 'comment', 'uncomment', or 'toggle'.")
+		flag.PrintDefaults()
+		return
+	}
+
+	if filename == "" {
+		fmt.Println("Please provide a filename to process.")
+		flag.PrintDefaults()
+		return
+	}
+
+	if startLabel == "" && endLabel != "" {
+		fmt.Println("Error: 'startLabel' is required when 'endLabel' is provided.")
+		return
+	} else if startLabel != "" && endLabel == "" {
+		fmt.Println("Error: 'endLabel' is required when 'startLabel' is provided.")
+		return
+	}
+
+	if startLabel != "" && lineStr != "" {
+		fmt.Println("Error: only  line OR label flags are allowed not both")
+	}
+
+	if startLabel != "" && lineStr != "" {
+		fmt.Println("Error: Specify either line number/range OR label, not both.")
+		return
+	}
+
+	if strings.Contains(filename, ",") {
+		if err := file.ProcessMultipleFiles(filename, dryRun); err != nil {
+			fmt.Println("Error processing files:", err)
+		}
+	} else {
+		if strings.Contains(filename, ":") {
+			parts := strings.Split(filename, ":")
+			if len(parts) != 2 {
+				fmt.Println("Invalid syntax format. Use '<filename>:<lines>'")
+				return
+			}
+			filename = parts[0]
+			lineStr = parts[1]
+		}
+		if err := file.ProcessSingleFile(filename, lineStr, startLabel, endLabel, modFunc, dryRun); err != nil {
+			fmt.Println("Error processing file:", err)
+		}
+	}
+}

internal/comment/comment.go

@@ -14,8 +14,8 @@ func Uncomment(line string, commentChars string) string {
 	trimmedLine := strings.TrimSpace(line)
 	if strings.HasPrefix(trimmedLine, commentChars) {
 		// Check for both `//` and `// ` prefixes.
-		if strings.HasPrefix(trimmedLine, commentChars + " ") {
-			return strings.Replace(line, commentChars + " ", "", 1)
+		if strings.HasPrefix(trimmedLine, commentChars+" ") {
+			return strings.Replace(line, commentChars+" ", "", 1)
 		}
 		return strings.Replace(line, commentChars, "", 1)
 	}

internal/file/file.go

@@ -15,7 +15,7 @@ import (
 )
 
 // ProcessFile processes a single file.
-func ProcessFile(filename string, lineNum [2]int, commentChars string, modFunc func(string, string) string, dryRun bool) error {
+func ProcessFile(filename string, lineNum [2]int, startLabel, endLabel string, commentChars string, modFunc func(string, string) string, dryRun bool) error {
 	inputFile, err := os.Open(filename)
 	if err != nil {
 		return err
@@ -24,7 +24,7 @@ func ProcessFile(filename string, lineNum [2]int, commentChars string, modFunc f
 
 	if dryRun {
 		// Perform a dry run: print the changes instead of writing them
-		return printChanges(inputFile, lineNum, commentChars, modFunc)
+		return printChanges(inputFile, lineNum, startLabel, endLabel, commentChars, modFunc)
 	}
 
 	// Create a backup of the original file
@@ -49,7 +49,7 @@ func ProcessFile(filename string, lineNum [2]int, commentChars string, modFunc f
 		return err
 	}
 
-	err = writeChanges(inputFile, tmpFile, lineNum, commentChars, modFunc)
+	err = writeChanges(inputFile, tmpFile, lineNum, startLabel, endLabel, commentChars, modFunc)
 	if err != nil {
 		restoreBackup(filename, backupFilename)
 		tmpFile.Close()
@@ -82,55 +82,88 @@ func ProcessFile(filename string, lineNum [2]int, commentChars string, modFunc f
 	return nil
 }
 
-func writeChanges(inputFile *os.File, outputFile *os.File, lineNum [2]int, commentChars string, modFunc func(string, string) string) error {
+func writeChanges(inputFile *os.File, outputFile *os.File, lineNum [2]int, startLabel, endLabel string, commentChars string, modFunc func(string, string) string) error {
 	scanner := bufio.NewScanner(inputFile)
 	writer := bufio.NewWriter(outputFile)
 	currentLine := 1
+	inSection := false
+	var err error
 
 	for scanner.Scan() {
 		lineContent := scanner.Text()
-		if lineNum[0] <= currentLine && currentLine <= lineNum[1] {
-			lineContent = modFunc(lineContent, commentChars)
+
+		// Determine if we are processing based on line numbers or labels
+		if startLabel != "" && endLabel != "" {
+			if strings.Contains(lineContent, startLabel) {
+				inSection = true
+			}
+			if inSection {
+				lineContent = modFunc(lineContent, commentChars)
+			}
+			if strings.Contains(lineContent, endLabel) {
+				inSection = false
+			}
+		} else {
+			if lineNum[0] <= currentLine && currentLine <= lineNum[1] {
+				lineContent = modFunc(lineContent, commentChars)
+			}
 		}
 
-		if _, err := writer.WriteString(lineContent + "\n"); err != nil {
+		if _, err = writer.WriteString(lineContent + "\n"); err != nil {
 			return err
 		}
 
 		currentLine++
 	}
 
-	if lineNum[1] > currentLine {
+	if lineNum[1] > currentLine && startLabel == "" && endLabel == "" {
 		return errors.New("line number is out of range")
 	}
 
-	if err := scanner.Err(); err != nil {
+	if err = scanner.Err(); err != nil {
 		return err
 	}
 
 	return writer.Flush()
 }
 
-func printChanges(inputFile *os.File, lineNum [2]int, commentChars string, modFunc func(string, string) string) error {
+func printChanges(inputFile *os.File, lineNum [2]int, startLabel, endLabel, commentChars string, modFunc func(string, string) string) error {
 	scanner := bufio.NewScanner(inputFile)
 	currentLine := 1
+	inSection := false
 
 	for scanner.Scan() {
 		lineContent := scanner.Text()
-		if lineNum[0] <= currentLine && currentLine <= lineNum[1] {
-			modified := modFunc(lineContent, commentChars)
-			fmt.Printf("%d: %s -> %s\n", currentLine, lineContent, modified)
+
+		// Determine if we are processing based on line numbers or labels
+		if startLabel != "" && endLabel != "" {
+			if strings.Contains(lineContent, startLabel) {
+				inSection = true
+			}
+			if inSection {
+				modified := modFunc(lineContent, commentChars)
+				fmt.Printf("%d: %s -> %s\n", currentLine, lineContent, modified)
+			}
+			if strings.Contains(lineContent, endLabel) {
+				inSection = false
+			}
+		} else {
+			if lineNum[0] <= currentLine && currentLine <= lineNum[1] {
+				modified := modFunc(lineContent, commentChars)
+				fmt.Printf("%d: %s -> %s\n", currentLine, lineContent, modified)
+			}
 		}
 
 		currentLine++
 	}
 
-	if lineNum[1] > currentLine {
+	if lineNum[1] > currentLine && startLabel == "" && endLabel == "" {
 		return errors.New("line number is out of range")
 	}
 
 	return scanner.Err()
 }
+
 func createBackup(filename, backupFilename string) error {
 	inputFile, err := os.Open(filename)
 	if err != nil {
@@ -160,19 +193,22 @@ func restoreBackup(filename, backupFilename string) {
 }
 
 // ProcessSingleFile processes a single file specified by filename.
-func ProcessSingleFile(filename string, lineStr string, modFunc func(string, string) string, dryRun bool) error {
-	startLine, endLine, err := extractLines(lineStr)
+func ProcessSingleFile(filename string, lineStr, startLabel, endLabel string, modFunc func(string, string) string, dryRun bool) error {
+	commentChars, err := selectCommentChars(filename)
 	if err != nil {
 		return err
 	}
-	lineNum := [2]int{startLine, endLine}
 
-	commentChars, err := selectCommentChars(filename)
-	if err != nil {
-		return err
+	var lineNum [2]int
+	if startLabel == "" && endLabel == "" {
+		startLine, endLine, err := extractLines(lineStr)
+		if err != nil {
+			return err
+		}
+		lineNum = [2]int{startLine, endLine}
 	}
 
-	return ProcessFile(filename, lineNum, commentChars, modFunc, dryRun)
+	return ProcessFile(filename, lineNum, startLabel, endLabel, commentChars, modFunc, dryRun)
 }
 
 // ProcessMultipleFiles processes multiple files specified by comma-separated filenames.
@@ -208,7 +244,7 @@ func processFileWithLines(fileInfo string, dryRun bool) error {
 		return err
 	}
 
-	return ProcessFile(file, lineNum, commentChars, comment.ToggleComments, dryRun)
+	return ProcessFile(file, lineNum, "", "", commentChars, comment.ToggleComments, dryRun)
 }
 
 func extractLines(lineStr string) (startLine, endLine int, err error) {