[language] Use a constructor to force correct canonication

fontscan/fontmap_test.go

@@ -11,6 +11,7 @@ import (
 	"time"
 
 	"github.com/go-text/typesetting/font"
+	"github.com/go-text/typesetting/language"
 	fontapi "github.com/go-text/typesetting/opentype/api/font"
 	meta "github.com/go-text/typesetting/opentype/api/metadata"
 	"github.com/go-text/typesetting/opentype/loader"
@@ -63,7 +64,7 @@ func ExampleFontMap_AddFace() {
 var _ shaping.Fontmap = (*FontMap)(nil)
 
 func TestResolveFont(t *testing.T) {
-	en, _ := NewLangID("en")
+	en, _ := NewLangID(language.NewLanguage("en"))
 
 	var logOutput bytes.Buffer
 	logger := log.New(&logOutput, "", 0)
@@ -115,7 +116,7 @@ func TestResolveForLang(t *testing.T) {
 	fm.SetQuery(Query{Families: []string{"helvetica"}})
 
 	// all system fonts should have support for english
-	en, _ := NewLangID("en")
+	en, _ := NewLangID(language.NewLanguage("en"))
 	face := fm.ResolveFaceForLang(en)
 	tu.AssertC(t, face != nil, "expected EN to be supported by system fonts")
 }
@@ -141,7 +142,7 @@ func TestResolveFallbackManual(t *testing.T) {
 	face := fm.ResolveFace('c')
 	tu.Assert(t, fm.FontLocation(face.Font).File == "user:Amiri")
 
-	en, _ := NewLangID("en")
+	en, _ := NewLangID(language.NewLanguage("en"))
 	face = fm.ResolveFaceForLang(en)
 	tu.Assert(t, face != nil && fm.FontLocation(face.Font).File == "user:Amiri")
 }

fontscan/langset.go

@@ -18,15 +18,16 @@ type LangID uint16
 // Derived languages not exactly supported are mapped to their primary part : for instance,
 // 'fr-be' is mapped to 'fr'
 func NewLangID(l language.Language) (LangID, bool) {
+	la := l.String()
 	const N = len(languagesRunes)
 	// binary search
 	i, j := 0, N
 	for i < j {
 		h := i + (j-i)/2
 		entry := languagesRunes[h]
-		if l < entry.lang {
+		if la < entry.lang {
 			j = h
-		} else if entry.lang < l {
+		} else if entry.lang < la {
 			i = h + 1
 		} else {
 			// extact match
@@ -35,7 +36,7 @@ func NewLangID(l language.Language) (LangID, bool) {
 	}
 	// i is the index where l should be :
 	// try to match the primary part
-	root := l.Primary()
+	root := l.Primary().String()
 	for ; i >= 0; i-- {
 		entry := languagesRunes[i]
 		if entry.lang > root { // keep going
@@ -76,7 +77,7 @@ func (ls LangSet) String() string {
 		for bit := 0; bit < 64; bit++ {
 			if page&(1<<bit) != 0 {
 				id := pageN<<6 | bit
-				chunks = append(chunks, string(languagesRunes[id].lang))
+				chunks = append(chunks, languagesRunes[id].lang)
 			}
 		}
 	}

fontscan/langset_gen.go

@@ -1,7 +1,5 @@
 package fontscan
 
-import "github.com/go-text/typesetting/language"
-
 // Copyright © 2002 Keith Packard
 //
 // Permission to use, copy, modify, distribute, and sell this software and its
@@ -24,7 +22,7 @@ import "github.com/go-text/typesetting/language"
 
 // languagesRunes stores the runes commonly used to write a language
 var languagesRunes = [...]struct {
-	lang  language.Language
+	lang  string
 	runes RuneSet // sorted, inclusive ranges
 }{
 	{ /** index: 0 */