add del command

add tests for all commands

wrap entry point with fang

add --version flag
target to Taskfile

cmd/del.go

@@ -0,0 +1,86 @@
+package cmd
+
+import (
+	"fmt"
+	"io"
+	"slices"
+
+	"github.com/spf13/cobra"
+)
+
+// delCmd represents the del command
+var delCmd = &cobra.Command{
+	Use:   "del",
+	Short: "Delete a pattern from the exclude file",
+	Long: `The del command removes a specified pattern from the .git/info/exclude file.
+This is useful for un-excluding files or directories that were previously excluded.`,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		ctx, ok := ContextObjectFromContext(cmd.Context())
+		if !ok {
+			return fmt.Errorf("no exclude file found in context")
+		}
+		if len(args) == 0 {
+			return fmt.Errorf("no pattern provided to delete")
+		}
+		pattern := args[0]
+		return runDelCommand(ctx.Out, ctx.File, pattern)
+	},
+}
+
+func init() {
+	RootCmd.AddCommand(delCmd)
+}
+
+// runDelCommand deletes the specified pattern from the exclude file and writes the updated content back
+// It handles both file and in-memory buffer cases for testing
+func runDelCommand(out io.Writer, f any, pattern string) error {
+	r, ok := f.(io.Reader)
+	if !ok {
+		return fmt.Errorf("provided file does not support Reader")
+	}
+	existingPatterns, err := readExistingPatterns(r)
+	if err != nil {
+		return fmt.Errorf("error reading existing patterns: %v", err)
+	}
+
+	if !slices.Contains(existingPatterns, pattern) {
+		fmt.Fprintf(out, "Pattern '%s' not found in the exclude file. Nothing to delete.\n", pattern)
+		return nil
+	}
+
+	var updatedPatterns []string
+	for _, p := range existingPatterns {
+		if p != pattern {
+			updatedPatterns = append(updatedPatterns, p)
+		}
+	}
+
+	var w io.Writer
+	if t, ok := f.(truncater); ok {
+		if err := t.Truncate(0); err != nil {
+			return fmt.Errorf("error truncating exclude file: %w", err)
+		}
+		if s, ok := f.(io.Seeker); ok {
+			if _, err := s.Seek(0, 0); err != nil {
+				return fmt.Errorf("error seeking to the beginning of exclude file: %w", err)
+			}
+		}
+		w, _ = f.(io.Writer)
+	} else if buf, ok := f.(interface{ Reset() }); ok {
+		buf.Reset()
+		w, _ = f.(io.Writer)
+	} else {
+		return fmt.Errorf("provided file does not support writing")
+	}
+
+	if err := writeDefaultExcludeContent(w); err != nil {
+		return fmt.Errorf("error writing default exclude content: %w", err)
+	}
+	for _, p := range updatedPatterns {
+		if _, err := fmt.Fprintln(w, p); err != nil {
+			return fmt.Errorf("error writing updated patterns to exclude file: %v", err)
+		}
+	}
+	fmt.Fprintf(out, "Deleted pattern '%s' from the exclude file.\n", pattern)
+	return nil
+}