feat: add error colors and refactor size utilities

Author: vukan322

cmd/root.go

@@ -1,6 +1,9 @@
 package cmd
 
 import (
+	"fmt"
+	"os"
+
 	"github.com/fatih/color"
 	"github.com/spf13/cobra"
 )
@@ -40,4 +43,10 @@ func init() {
 	rootCmd.PersistentFlags().IntVar(&days, "days", 14, "Only process node_modules not modified in N days")
 	rootCmd.PersistentFlags().BoolVar(&includeHidden, "include-hidden", false, "Include hidden directories (starting with .)")
 	rootCmd.PersistentFlags().BoolVarP(&quiet, "quiet", "q", false, "Minimal output (summary only)")
+
+	rootCmd.SetFlagErrorFunc(func(cmd *cobra.Command, err error) error {
+		fmt.Fprintf(os.Stderr, "%s %s\n", red("Error:"), err)
+		_ = cmd.Usage()
+		return nil
+	})
 }

internal/scanner/scanner.go

@@ -8,9 +8,15 @@ import (
 	"strings"
 	"time"
 
+	"github.com/fatih/color"
 	"github.com/vukan322/nuke-node_modules/internal/util"
 )
 
+var (
+	yellow = color.New(color.FgYellow).SprintFunc()
+	red    = color.New(color.FgRed).SprintFunc()
+)
+
 type Scanner struct {
 	rootPath      string
 	days          int
@@ -45,7 +51,7 @@ func (s *Scanner) Scan() (*ScanResult, error) {
 	err = filepath.WalkDir(s.rootPath, func(path string, d fs.DirEntry, err error) error {
 		if err != nil {
 			if s.verbose {
-				fmt.Fprintf(os.Stderr, "Warning: cannot access %s: %v\n", path, err)
+				fmt.Fprintf(os.Stderr, "%s %s: %v\n", yellow("Warning:"), path, err)
 			}
 			return nil
 		}
@@ -56,7 +62,7 @@ func (s *Scanner) Scan() (*ScanResult, error) {
 
 		if d.Type()&os.ModeSymlink != 0 {
 			if s.verbose {
-				fmt.Fprintf(os.Stderr, "Skipping symlink: %s\n", path)
+				fmt.Fprintf(os.Stderr, "%s %s\n", yellow("Skipping symlink:"), path)
 			}
 			return fs.SkipDir
 		}
@@ -71,21 +77,21 @@ func (s *Scanner) Scan() (*ScanResult, error) {
 		info, err := d.Info()
 		if err != nil {
 			if s.verbose {
-				fmt.Fprintf(os.Stderr, "Warning: cannot get info for %s: %v\n", path, err)
+				fmt.Fprintf(os.Stderr, "%s cannot get info for %s: %v\n", yellow("Warning:"), path, err)
 			}
 			return nil
 		}
 
 		if getDevice(info) != s.rootDev {
 			if s.verbose {
-				fmt.Fprintf(os.Stderr, "Skipping different filesystem: %s\n", path)
+				fmt.Fprintf(os.Stderr, "%s %s\n", yellow("Skipping different filesystem:"), path)
 			}
 			return fs.SkipDir
 		}
 
 		if d.Name() == "node_modules" {
 			if info.ModTime().Before(s.cutoffTime) {
-				size := calculateSize(path)
+				size := util.CalculateSize(path)
 				folder := FolderInfo{
 					Path:         path,
 					Size:         size,
@@ -133,7 +139,7 @@ func (s *Scanner) Delete(result *ScanResult) (*ScanResult, error) {
 		if err != nil {
 			failures = append(failures, fmt.Sprintf("%s: %v", folder.Path, err))
 			if s.verbose {
-				fmt.Fprintf(os.Stderr, "Failed to delete %s: %v\n", folder.Path, err)
+				fmt.Fprintf(os.Stderr, "%s %s: %v\n", red("Failed to delete"), folder.Path, err)
 			}
 			continue
 		}
@@ -153,20 +159,3 @@ func (s *Scanner) Delete(result *ScanResult) (*ScanResult, error) {
 
 	return deleted, nil
 }
-
-func calculateSize(path string) int64 {
-	var size int64
-	_ = filepath.WalkDir(path, func(_ string, d fs.DirEntry, err error) error {
-		if err != nil {
-			return nil
-		}
-		if !d.IsDir() {
-			info, err := d.Info()
-			if err == nil {
-				size += info.Size()
-			}
-		}
-		return nil
-	})
-	return size
-}

internal/scanner/scanner_test.go

@@ -161,18 +161,30 @@ func TestScan_MultipleNodeModules(t *testing.T) {
 	project1 := filepath.Join(tmpDir, "project1")
 	project2 := filepath.Join(tmpDir, "project2")
 
-	os.Mkdir(project1, 0755)
-	os.Mkdir(project2, 0755)
+	if err := os.Mkdir(project1, 0755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Mkdir(project2, 0755); err != nil {
+		t.Fatal(err)
+	}
 
 	nm1 := filepath.Join(project1, "node_modules")
 	nm2 := filepath.Join(project2, "node_modules")
 
-	os.Mkdir(nm1, 0755)
-	os.Mkdir(nm2, 0755)
+	if err := os.Mkdir(nm1, 0755); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Mkdir(nm2, 0755); err != nil {
+		t.Fatal(err)
+	}
 
 	oldTime := time.Now().AddDate(0, 0, -30)
-	os.Chtimes(nm1, oldTime, oldTime)
-	os.Chtimes(nm2, oldTime, oldTime)
+	if err := os.Chtimes(nm1, oldTime, oldTime); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Chtimes(nm2, oldTime, oldTime); err != nil {
+		t.Fatal(err)
+	}
 
 	s := New(tmpDir, 14, false, false)
 	result, err := s.Scan()
@@ -200,7 +212,9 @@ func TestDelete_RemovesNodeModules(t *testing.T) {
 	}
 
 	oldTime := time.Now().AddDate(0, 0, -30)
-	os.Chtimes(nmPath, oldTime, oldTime)
+	if err := os.Chtimes(nmPath, oldTime, oldTime); err != nil {
+		t.Fatal(err)
+	}
 
 	s := New(tmpDir, 0, false, false)
 	scanResult, _ := s.Scan()

internal/ui/output.go

@@ -10,7 +10,6 @@ import (
 
 var (
 	green  = color.New(color.FgGreen).SprintFunc()
-	red    = color.New(color.FgRed).SprintFunc()
 	yellow = color.New(color.FgYellow).SprintFunc()
 	cyan   = color.New(color.FgCyan).SprintFunc()
 )

internal/util/format.go

@@ -0,0 +1,37 @@
+package util
+
+import (
+	"fmt"
+	"io/fs"
+	"path/filepath"
+)
+
+func FormatSize(bytes int64) string {
+	const unit = 1024
+	if bytes < unit {
+		return fmt.Sprintf("%d B", bytes)
+	}
+	div, exp := int64(unit), 0
+	for n := bytes / unit; n >= unit; n /= unit {
+		div *= unit
+		exp++
+	}
+	return fmt.Sprintf("%.1f %cB", float64(bytes)/float64(div), "KMGTPE"[exp])
+}
+
+func CalculateSize(path string) int64 {
+	var size int64
+	_ = filepath.WalkDir(path, func(_ string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return nil
+		}
+		if !d.IsDir() {
+			info, err := d.Info()
+			if err == nil {
+				size += info.Size()
+			}
+		}
+		return nil
+	})
+	return size
+}

internal/util/format_test.go

@@ -0,0 +1,49 @@
+package util
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestFormatSize(t *testing.T) {
+	tests := []struct {
+		bytes    int64
+		expected string
+	}{
+		{0, "0 B"},
+		{1023, "1023 B"},
+		{1024, "1.0 KB"},
+		{1536, "1.5 KB"},
+		{1048576, "1.0 MB"},
+		{1073741824, "1.0 GB"},
+	}
+
+	for _, tt := range tests {
+		result := FormatSize(tt.bytes)
+		if result != tt.expected {
+			t.Errorf("FormatSize(%d) = %s, want %s", tt.bytes, result, tt.expected)
+		}
+	}
+}
+
+func TestCalculateSize(t *testing.T) {
+	tmpDir := t.TempDir()
+
+	file1 := filepath.Join(tmpDir, "file1.txt")
+	if err := os.WriteFile(file1, make([]byte, 1024), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	file2 := filepath.Join(tmpDir, "file2.txt")
+	if err := os.WriteFile(file2, make([]byte, 512), 0644); err != nil {
+		t.Fatal(err)
+	}
+
+	size := CalculateSize(tmpDir)
+	expected := int64(1024 + 512)
+
+	if size != expected {
+		t.Errorf("CalculateSize() = %d, want %d", size, expected)
+	}
+}