create a package-scoped instance

refactoring

cmd/pathctl/main.go

@@ -7,8 +7,8 @@ import (
 	"os"
 	"strings"
 
+	"al.essio.dev/pkg/tools/dirlist"
 	"al.essio.dev/pkg/tools/internal/version"
-	"al.essio.dev/pkg/tools/pathlist"
 )
 
 const (
@@ -27,7 +27,7 @@ var (
 	envVar string
 )
 
-var cmdHandlers map[string]func(d pathlist.List)
+var cmdHandlers map[string]func(d dirlist.List)
 
 func init() {
 	flag.BoolVar(&helpMode, "help", false, "display this help and exit.")
@@ -39,22 +39,22 @@ func init() {
 	flag.Usage = usage
 	flag.CommandLine.SetOutput(os.Stderr)
 
-	cmdHandlers = func() map[string]func(pathlist.List) {
-		hAppend := func(d pathlist.List) {
+	cmdHandlers = func() map[string]func(dirlist.List) {
+		hAppend := func(d dirlist.List) {
 			if dropMode {
 				d.Drop(flag.Arg(1))
 			}
 			d.Append(flag.Arg(1))
 		}
-		hDrop := func(d pathlist.List) { d.Drop(flag.Arg(1)) }
-		hPrepend := func(d pathlist.List) {
+		hDrop := func(d dirlist.List) { d.Drop(flag.Arg(1)) }
+		hPrepend := func(d dirlist.List) {
 			if dropMode {
 				d.Drop(flag.Arg(1))
 			}
 			d.Prepend(flag.Arg(1))
 		}
 
-		return map[string]func(pathlist.List){
+		return map[string]func(dirlist.List){
 			"append":  hAppend,
 			"drop":    hDrop,
 			"prepend": hPrepend,
@@ -75,7 +75,7 @@ func main() {
 
 	handleHelpAndVersionModes()
 
-	dirs := pathlist.New()
+	dirs := dirlist.New()
 	dirs.LoadEnv(envVar)
 
 	if flag.NArg() < 1 {
@@ -91,7 +91,7 @@ func main() {
 	}
 }
 
-func printPathList(d pathlist.List) {
+func printPathList(d dirlist.List) {
 	var sb = strings.Builder{}
 	sb.Reset()
 

dirlist/dirlist.go

@@ -0,0 +1,43 @@
+package dirlist
+
+var (
+	dList List
+)
+
+func init() {
+	dList = New()
+}
+
+func Reset() { dList.Reset() }
+
+func Contains(p string) bool {
+	return dList.Contains(quoteAndClean(p))
+}
+
+func Load(s string) {
+	dList.Load(s)
+}
+
+func LoadEnv(s string) {
+	dList.LoadEnv(s)
+}
+
+func Prepend(p string) {
+	dList.Prepend(p)
+}
+
+func Append(p string) {
+	dList.Append(p)
+}
+
+func Drop(p string) {
+	dList.Drop(p)
+}
+
+func Slice() []string {
+	return dList.Slice()
+}
+
+func String() string {
+	return dList.String()
+}

dirlist/dirlist_test.go

@@ -0,0 +1,97 @@
+package dirlist
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestAppend(t *testing.T) {
+	Reset()
+	require.Equal(t, "", String())
+	for _, p := range []string{"/var", "/var", "/bin", "/bin/", "/bin///"} {
+		Append(p)
+	}
+
+	require.Equal(t, "/var:/bin", String())
+	Prepend("/bin///")
+	require.Equal(t, "/var:/bin", String())
+}
+
+func TestContains(t *testing.T) {
+	Reset()
+	Load("/opt/local/bin:/usr/local/bin:/sbin:/bin:/var:/bin")
+	require.False(t, Contains("/ur/local/sbin"))
+	require.False(t, Contains("/ur/local////sbin/"))
+	require.True(t, Contains("/sbin"))
+	require.True(t, Contains("///sbin//"))
+
+}
+
+func TestDrop(t *testing.T) {
+	Reset()
+	Load("/opt/local/bin:/usr/local/bin:/sbin:/bin:/var:/bin")
+	require.Equal(t, Slice(), []string{"/opt/local/bin", "/usr/local/bin", "/sbin", "/bin", "/var"})
+	Drop("/opt/local/bin")
+	Drop("/opt/local/bin")
+	Drop("/opt/local/bin")
+	Drop("/usr/local/bin")
+	Drop("/var")
+	require.NotEqual(t, "", String())
+	Drop("/sbin")
+	Drop("/bin")
+	require.False(t, Contains("/bin"))
+	require.Equal(t, "", String())
+
+	Reset()
+	require.NotPanics(t, func() { Drop("") })
+}
+
+func TestLoadEnv(t *testing.T) {
+	tests := []struct {
+		name string
+		val  string
+		want string
+	}{
+		{"empty", "", ""},
+	}
+	for i, tt := range tests {
+		tt2 := tt
+		t.Run(tt2.name, func(t *testing.T) {
+			envvar := fmt.Sprintf("%s_%d_VAR", t.Name(), i)
+			Reset()
+			t.Setenv(envvar, tt.val)
+			LoadEnv(envvar)
+			require.Equal(t, tt2.want, String())
+		})
+	}
+}
+
+func TestPrepend(t *testing.T) {
+	Reset()
+	require.Equal(t, "", String())
+	for _, p := range []string{"/var", "/var", "/bin", "/bin/", "/bin///"} {
+		Append(p)
+	}
+
+	require.Equal(t, "/var:/bin", String())
+	Prepend("/bin///")
+	require.Equal(t, "/var:/bin", String())
+}
+
+func TestSlice(t *testing.T) {
+	Reset()
+	require.Equal(t, 0, len(Slice()))
+	Prepend("/usr/bin")
+	Append("/bin")
+	require.Equal(t, []string{"/usr/bin", "/bin"}, Slice())
+}
+
+func TestString(t *testing.T) {
+	Reset()
+	require.Equal(t, "", String())
+	Prepend("/usr/bin")
+	Append("/bin")
+	require.Equal(t, "/usr/bin:/bin", String())
+}

pathlist/list.go → dirlist/list.go

@@ -1,8 +1,9 @@
-// Package pathlist implements functions to manipulate PATH-like
+// Package dirlist implements functions to manipulate PATH-like
 // environment variables.
-package pathlist
+package dirlist
 
 import (
+	"fmt"
 	"os"
 	"path/filepath"
 	"slices"
@@ -22,7 +23,7 @@ type List interface {
 	Contains(string) bool
 
 	// Nil returns true if the list is emppty.
-	Nil() bool
+	//	Nil() bool
 
 	// Load reads the list of directories from a string.
 	Load(string)
@@ -62,16 +63,16 @@ func New() List {
 }
 
 func (d *dirList) Contains(p string) bool {
-	return slices.Contains(d.lst, p)
+	return slices.Contains(d.lst, quoteAndClean(p))
 }
 
 func (d *dirList) Reset() {
 	d.init()
 }
 
-func (d *dirList) Nil() bool {
-	return d.lst == nil || len(d.lst) == 0
-}
+// func (d *dirList) Nil() bool {
+// 	return d.l == nil || len(d.l) == 0
+// }
 
 func (d *dirList) Load(s string) {
 	d.src = s
@@ -82,26 +83,25 @@ func (d *dirList) LoadEnv(s string) {
 	d.Load(os.Getenv(s))
 }
 
-func (d *dirList) Slice() []string {
-	if d.Nil() {
-		return []string{}
+func (d *dirList) Slice() (dst []string) {
+	if len(d.lst) == 0 {
+		return
 	}
 
-	dst := make([]string, len(d.lst))
-	n := copy(dst, d.lst)
-	if n != len(d.lst) {
-		panic("couldn't copy the list")
+	dst = make([]string, len(d.lst))
+	if n := copy(dst, d.lst); n == len(d.lst) {
+		return dst
 	}
 
-	return dst
+	panic("couldn't copy the list")
 }
 
 func (d *dirList) String() string {
-	if !d.Nil() {
-		return strings.Join(d.lst, string(filepath.ListSeparator))
+	if len(d.lst) == 0 {
+		return ""
 	}
 
-	return ""
+	return strings.Join(d.lst, string(filepath.ListSeparator))
 }
 
 func (d *dirList) load() {
@@ -110,7 +110,7 @@ func (d *dirList) load() {
 
 func (d *dirList) Append(path string) {
 	p := quoteAndClean(path)
-	if d.Nil() {
+	if len(d.lst) == 0 {
 		d.lst = []string{p}
 		return
 	}
@@ -121,9 +121,10 @@ func (d *dirList) Append(path string) {
 }
 
 func (d *dirList) Drop(path string) {
-	if d.Nil() {
+	if len(d.lst) == 0 {
 		return
 	}
+
 	p := quoteAndClean(path)
 
 	if idx := slices.Index(d.lst, p); idx != -1 {
@@ -133,7 +134,7 @@ func (d *dirList) Drop(path string) {
 
 func (d *dirList) Prepend(path string) {
 	p := quoteAndClean(path)
-	if d.Nil() {
+	if len(d.lst) == 0 {
 		d.lst = []string{p}
 		return
 	}
@@ -149,12 +150,16 @@ func (d *dirList) init() {
 }
 
 func (d *dirList) cleanPathVar() []string {
-	if d.src == "" {
+	return cleanPathVar(d.src)
+}
+
+func cleanPathVar(src string) []string {
+	if src == "" {
 		return nil
 	}
 
-	pthSlice := filepath.SplitList(d.src)
-	if pthSlice == nil {
+	pthSlice := filepath.SplitList(src)
+	if len(pthSlice) == 0 {
 		return nil
 	}
 
@@ -163,8 +168,13 @@ func (d *dirList) cleanPathVar() []string {
 
 func (d *dirList) clone(o *dirList) *dirList {
 	o.src = d.src
-	o.lst = make([]string, len(d.lst))
-	copy(o.lst, d.lst)
+
+	n := len(d.lst)
+	o.lst = make([]string, n)
+
+	if m := copy(o.lst, d.lst); n != m {
+		panic(fmt.Sprintf("copy: expected %d items, got %d", n, m))
+	}
 
 	return o
 }
@@ -190,12 +200,19 @@ func removeDups(col []string, applyFn func(string) (string, bool)) []string {
 }
 
 var filterEmptyStrings = func(s string) (string, bool) {
-	clean := filepath.Clean(s)
-	if clean != "" {
-		return clean, true
+	if strings.TrimSpace(s) == "" {
+		return s, false
 	}
 
-	return clean, false
+	// I removed the following because filepath.Clean()
+	// never returns "".
+	//
+	// clean := filepath.Clean(s)
+	// if clean == "" {
+	// 	return clean, false
+	// }
+
+	return filepath.Clean(s), true
 }
 
 func quoteAndClean(s string) string {