vendor tsgo

tools/tsgo/internal/transformers/modifiervisitor.go

@@ -0,0 +1,28 @@
+package transformers
+
+import (
+	"github.com/microsoft/typescript-go/internal/ast"
+	"github.com/microsoft/typescript-go/internal/printer"
+)
+
+type modifierVisitor struct {
+	Transformer
+	AllowedModifiers ast.ModifierFlags
+}
+
+func (v *modifierVisitor) visit(node *ast.Node) *ast.Node {
+	flags := ast.ModifierToFlag(node.Kind)
+	if flags != ast.ModifierFlagsNone && flags&v.AllowedModifiers == 0 {
+		return nil
+	}
+	return node
+}
+
+func ExtractModifiers(emitContext *printer.EmitContext, modifiers *ast.ModifierList, allowed ast.ModifierFlags) *ast.ModifierList {
+	if modifiers == nil {
+		return nil
+	}
+	tx := modifierVisitor{AllowedModifiers: allowed}
+	tx.NewTransformer(tx.visit, emitContext)
+	return tx.visitor.VisitModifiers(modifiers)
+}