Expand Gotlin language and tooling

internal/lang/index_test.go

@@ -0,0 +1,26 @@
+package lang
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestGenerateGoIndexedDataClassSelector(t *testing.T) {
+	prog, err := Parse(`
+package demo
+
+data class User(var id: String)
+
+fun first(users: List<User>): String { return users[0].id }
+`)
+	if err != nil {
+		t.Fatalf("parse failed: %v", err)
+	}
+	out, err := GenerateGo(prog)
+	if err != nil {
+		t.Fatalf("generation failed: %v", err)
+	}
+	if !strings.Contains(string(out), "return users[0].Id") {
+		t.Fatalf("generated Go missing indexed selector:\n%s", out)
+	}
+}