feat(04-02): select CLDR and Laravel plural forms with PHP parameters

- Use go-i18n only to pick a category label, then substitute :name/:Name/:NAME
- Treat YAML maps as plurals when all keys are locale CLDR categories
- Parse pipe strings with {n} and [a,b]/[a,*] conditions at catalog load

Co-authored-by: Cursor <cursoragent@cursor.com>

phrasebook/translator_test.go

@@ -96,3 +96,96 @@ func (p *langPlugin) Requires() []string           { return nil }
 func (p *langPlugin) Register(*backpack.App) error { return nil }
 func (p *langPlugin) Boot(*backpack.App) error     { return nil }
 func (p *langPlugin) LangFS() fs.FS                { return p.fsys }
+
+func TestPluralSmoke(t *testing.T) {
+	t.Parallel()
+
+	fsys := fstest.MapFS{
+		"lang/en/lang.yaml": {Data: []byte("" +
+			"albums:\n  one: \":count album\"\n  other: \":count albums\"\n" +
+			"items: \"{0} No items|{1} One item|[2,*] :count items\"\n" +
+			"helloName: \"hi :name :Name :NAME\"\n" +
+			"raw:\n  other: \"{{.Count}} bottles\"\n")},
+		"lang/pl/lang.yaml": {Data: []byte("" +
+			"albums:\n  one: \":count album\"\n  few: \":count albumy\"\n  many: \":count albumów\"\n  other: \":count albumu\"\n" +
+			"posts: \":count wpis|:count wpisy|:count wpisów|:count wpisu\"\n")},
+	}
+	cat := NewCatalog()
+	if err := cat.Load("golem15.hello", fsys); err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	tr := NewTranslator(cat, Options{})
+
+	pl := map[any]string{1: "1 album", 2: "2 albumy", 5: "5 albumów", 22: "22 albumy", 0: "0 albumów", 1.5: "1.5 albumu"}
+	for n, want := range pl {
+		if got := tr.ChoiceIn("pl", "golem15.hello::lang.albums", n, nil); got != want {
+			t.Fatalf("pl albums %v = %q, want %q", n, got, want)
+		}
+	}
+	en := map[any]string{1: "1 album", 2: "2 albums", 0: "0 albums", 1.5: "1.5 albums"}
+	for n, want := range en {
+		if got := tr.ChoiceIn("en", "golem15.hello::lang.albums", n, nil); got != want {
+			t.Fatalf("en albums %v = %q, want %q", n, got, want)
+		}
+	}
+	if got := tr.ChoiceIn("pl", "golem15.hello::lang.posts", 1, nil); got != "1 wpis" {
+		t.Fatalf("pl posts 1 = %q", got)
+	}
+	if got := tr.ChoiceIn("pl", "golem15.hello::lang.posts", 2, nil); got != "2 wpisy" {
+		t.Fatalf("pl posts 2 = %q", got)
+	}
+	if got := tr.ChoiceIn("pl", "golem15.hello::lang.posts", 5, nil); got != "5 wpisów" {
+		t.Fatalf("pl posts 5 = %q", got)
+	}
+	if got := tr.ChoiceIn("pl", "golem15.hello::lang.posts", 22, nil); got != "22 wpisy" {
+		t.Fatalf("pl posts 22 = %q", got)
+	}
+	if got := tr.ChoiceIn("en", "golem15.hello::lang.items", 0, nil); got != "No items" {
+		t.Fatalf("items 0 = %q", got)
+	}
+	if got := tr.ChoiceIn("en", "golem15.hello::lang.items", 1, nil); got != "One item" {
+		t.Fatalf("items 1 = %q", got)
+	}
+	if got := tr.ChoiceIn("en", "golem15.hello::lang.items", 5, nil); got != "5 items" {
+		t.Fatalf("items 5 = %q", got)
+	}
+	if got := tr.ChoiceIn("en", "golem15.hello::lang.helloName", 1, map[string]string{"name": "alice"}); got != "hi alice Alice ALICE" {
+		t.Fatalf("params = %q", got)
+	}
+	if got := tr.ChoiceIn("en", "golem15.hello::lang.raw", 2, nil); got != "{{.Count}} bottles" {
+		t.Fatalf("go-i18n must not evaluate YAML as a template, got %q", got)
+	}
+
+	t.Run("invalid category for locale", func(t *testing.T) {
+		err := NewCatalog().Load("golem15.hello", fstest.MapFS{
+			"lang/en/lang.yaml": {Data: []byte("albums:\n  few: x\n  other: y\n")},
+		})
+		if err == nil || !strings.Contains(err.Error(), "invalid plural category") {
+			t.Fatalf("want invalid category, got %v", err)
+		}
+	})
+	t.Run("missing other", func(t *testing.T) {
+		err := NewCatalog().Load("golem15.hello", fstest.MapFS{
+			"lang/en/lang.yaml": {Data: []byte("albums:\n  one: x\n")},
+		})
+		if err == nil || !strings.Contains(err.Error(), "requires other") {
+			t.Fatalf("want missing other, got %v", err)
+		}
+	})
+	t.Run("malformed pipe", func(t *testing.T) {
+		err := NewCatalog().Load("golem15.hello", fstest.MapFS{
+			"lang/en/lang.yaml": {Data: []byte("items: \"{x} nope|{1} one\"\n")},
+		})
+		if err == nil || !strings.Contains(err.Error(), "malformed pipe") {
+			t.Fatalf("want malformed pipe, got %v", err)
+		}
+	})
+	t.Run("incomplete pipe", func(t *testing.T) {
+		err := NewCatalog().Load("golem15.hello", fstest.MapFS{
+			"lang/en/lang.yaml": {Data: []byte("items: \":count post|:count posts|:count extra\"\n")},
+		})
+		if err == nil || !strings.Contains(err.Error(), "incomplete pipe") {
+			t.Fatalf("want incomplete pipe, got %v", err)
+		}
+	})
+}