llgen: support go.mod

internal/llgen/llgen.go

@@ -25,6 +25,7 @@ import (
 
 	"github.com/goplus/gogen/packages"
 	"github.com/goplus/llgo/cl"
+	"github.com/goplus/llgo/internal/mod"
 	"golang.org/x/tools/go/ssa"
 	"golang.org/x/tools/go/ssa/ssautil"
 
@@ -37,20 +38,29 @@ func Init() {
 	cl.SetDebug(cl.DbgFlagAll)
 }
 
-func Do(inFile, outFile string) {
-	ret := Gen(inFile, nil)
+func PkgPath(dir string) string {
+	_, pkgPath, err := mod.Load(dir)
+	check(err)
+	return pkgPath
+}
+
+func Do(pkgPath, inFile, outFile string) {
+	ret := Gen(pkgPath, inFile, nil)
 	err := os.WriteFile(outFile, []byte(ret), 0644)
 	check(err)
 }
 
-func Gen(inFile string, src any) string {
+func Gen(pkgPath, inFile string, src any) string {
 	fset := token.NewFileSet()
 	f, err := parser.ParseFile(fset, inFile, src, parser.ParseComments)
 	check(err)
 
 	files := []*ast.File{f}
 	name := f.Name.Name
-	pkg := types.NewPackage(name, name)
+	if pkgPath == "" {
+		pkgPath = name
+	}
+	pkg := types.NewPackage(pkgPath, name)
 	imp := packages.NewImporter(fset)
 	ssaPkg, _, err := ssautil.BuildPackage(
 		&types.Config{Importer: imp}, fset, pkg, files, ssa.SanityCheckFunctions)