fix: fix uncaught insufficient permission error

Switching over errors does not work with wrapped errors. Prefer the more
verbose errors.Is instead.

Author: Tshaka Eric Lekholoane

internal/cli/cli.go

@@ -158,17 +158,17 @@ func (a *app) capacity() { a.show(power.Capacity) }
 
 func (a *app) persist() {
 	if err := a.systemder.Write(); err != nil {
-		switch err {
-		case systemd.ErrBashNotFound:
+		switch {
+		case errors.Is(err, systemd.ErrBashNotFound):
 			a.errorln(msgBashNotFound)
 			return
-		case systemd.ErrIncompatSystemd:
+		case errors.Is(err, systemd.ErrIncompatSystemd):
 			a.errorln(msgIncompatibleSystemd)
 			return
-		case power.ErrNotFound:
+		case errors.Is(err, power.ErrNotFound):
 			a.errorln(msgIncompatible)
 			return
-		case syscall.EACCES:
+		case errors.Is(err, syscall.EACCES):
 			a.errorln(msgPermissionDenied)
 			return
 		default:
@@ -269,11 +269,11 @@ func (a *app) threshold(args []string) {
 		}
 
 		if err := a.set(power.Threshold, strings.TrimSpace(val)); err != nil {
-			switch err {
-			case power.ErrNotFound:
+			switch {
+			case errors.Is(err, power.ErrNotFound):
 				a.errorln(msgIncompatible)
 				return
-			case syscall.EACCES:
+			case errors.Is(err, syscall.EACCES):
 				a.errorln(msgPermissionDenied)
 				return
 			default:
@@ -294,9 +294,10 @@ func Run() {
 			out:  os.Stdout,
 			quit: os.Exit,
 		},
-		pager: "less",
-		get:   power.Get,
-		set:   power.Set,
+		pager:     "less",
+		get:       power.Get,
+		set:       power.Set,
+		systemder: systemd.New(),
 	}
 
 	if len(os.Args) == 1 {

internal/cli/cli_test.go

@@ -3,6 +3,7 @@ package cli
 import (
 	"bytes"
 	"fmt"
+	"io/fs"
 	"os/exec"
 	"syscall"
 	"testing"
@@ -217,7 +218,7 @@ func TestPersist(t *testing.T) {
 		{systemd.ErrBashNotFound, msgBashNotFound, failure},
 		{systemd.ErrIncompatSystemd, msgIncompatibleSystemd, failure},
 		{power.ErrNotFound, msgIncompatible, failure},
-		{syscall.EACCES, msgPermissionDenied, failure},
+		{&fs.PathError{Err: syscall.EACCES}, msgPermissionDenied, failure},
 	}
 
 	for _, test := range tests {
@@ -261,7 +262,7 @@ func TestReset(t *testing.T) {
 		code int
 	}{
 		{nil, msgPersistenceReset, success},
-		{syscall.EACCES, msgPermissionDenied, failure},
+		{&fs.PathError{Err: syscall.EACCES}, msgPermissionDenied, failure},
 	}
 
 	for _, test := range tests {
@@ -310,7 +311,7 @@ func TestThreshold(t *testing.T) {
 		{[]string{"bat", "threshold", "80.0"}, failure, nil, msgArgNotInt},
 		{[]string{"bat", "threshold", "101"}, failure, nil, msgOutOfRangeThresholdVal},
 		{[]string{"bat", "threshold", "80"}, failure, power.ErrNotFound, msgIncompatible},
-		{[]string{"bat", "threshold", "80"}, failure, syscall.EACCES, msgPermissionDenied},
+		{[]string{"bat", "threshold", "80"}, failure, &fs.PathError{Err: syscall.EACCES}, msgPermissionDenied},
 	}
 
 	for _, test := range tests {