chore(all): use casers instead of strings.Title

- Add `golang.org/x/text` dependency
- Update code to use `cases.Title(language.English)`

internal/updater/providers/ipvanish/filename.go

@@ -6,11 +6,12 @@ import (
 	"strings"
 
 	"github.com/qdm12/gluetun/internal/constants"
+	"golang.org/x/text/cases"
 )
 
 var errCountryCodeUnknown = errors.New("country code is unknown")
 
-func parseFilename(fileName, hostname string) (
+func parseFilename(fileName, hostname string, titleCaser cases.Caser) (
 	country, city string, err error) {
 	const prefix = "ipvanish-"
 	s := strings.TrimPrefix(fileName, prefix)
@@ -28,11 +29,11 @@ func parseFilename(fileName, hostname string) (
 	if !ok {
 		return "", "", fmt.Errorf("%w: %s", errCountryCodeUnknown, countryCode)
 	}
-	country = strings.Title(country)
+	country = titleCaser.String(country)
 
 	if len(parts) > 1 {
 		city = strings.Join(parts[1:], " ")
-		city = strings.Title(city)
+		city = titleCaser.String(city)
 	}
 
 	return country, city, nil

internal/updater/providers/ipvanish/filename_test.go

@@ -6,6 +6,8 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
 )
 
 func Test_parseFilename(t *testing.T) {
@@ -39,7 +41,8 @@ func Test_parseFilename(t *testing.T) {
 		t.Run(name, func(t *testing.T) {
 			t.Parallel()
 
-			country, city, err := parseFilename(testCase.fileName, testCase.hostname)
+			titleCaser := cases.Title(language.English)
+			country, city, err := parseFilename(testCase.fileName, testCase.hostname, titleCaser)
 
 			if testCase.err != nil {
 				require.Error(t, err)

internal/updater/providers/ipvanish/servers.go

@@ -12,6 +12,8 @@ import (
 	"github.com/qdm12/gluetun/internal/updater/openvpn"
 	"github.com/qdm12/gluetun/internal/updater/resolver"
 	"github.com/qdm12/gluetun/internal/updater/unzip"
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
 )
 
 var ErrNotEnoughServers = errors.New("not enough servers found")
@@ -30,6 +32,7 @@ func GetServers(ctx context.Context, unzipper unzip.Unzipper,
 
 	hts := make(hostToServer)
 
+	titleCaser := cases.Title(language.English)
 	for fileName, content := range contents {
 		if !strings.HasSuffix(fileName, ".ovpn") {
 			continue // not an OpenVPN file
@@ -54,7 +57,7 @@ func GetServers(ctx context.Context, unzipper unzip.Unzipper,
 			continue
 		}
 
-		country, city, err := parseFilename(fileName, hostname)
+		country, city, err := parseFilename(fileName, hostname, titleCaser)
 		if err != nil {
 			// treat error as warning and go to next file
 			warning := err.Error() + " in " + fileName