Handle unicode correctly in CallPrinter

src/ast/prettyprinter.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_AST_PRETTYPRINTER_H_
 #define V8_AST_PRETTYPRINTER_H_
 
 #include "src/allocation.h"
 #include "src/ast/ast.h"
 #include "src/base/compiler-specific.h"
+#include "src/string-builder.h"
 
 namespace v8 {
 namespace internal {
 
 class CallPrinter final : public AstVisitor<CallPrinter> {
  public:
   explicit CallPrinter(Isolate* isolate, bool is_builtin);
-  ~CallPrinter();
 
   // The following routine prints the node with position |position| into a
-  // string. The result string is alive as long as the CallPrinter is alive.
-  const char* Print(FunctionLiteral* program, int position);
-
-  void PRINTF_FORMAT(2, 3) Print(const char* format, ...);
-
-  void Find(AstNode* node, bool print = false);
+  // string.
+  Handle<String> Print(FunctionLiteral* program, int position);
 
 // Individual nodes
 #define DECLARE_VISIT(type) void Visit##type(type* node);
   AST_NODE_LIST(DECLARE_VISIT)
 #undef DECLARE_VISIT
 
  private:
-  void Init();
+  // void PRINTF_FORMAT(2, 3) Print(const char* format, ...);
+  void Print(const char* str);
+  void Print(Handle<String> str);
+
+  void Find(AstNode* node, bool print = false);
+
   Isolate* isolate_;
-  char* output_;  // output string buffer
-  int size_;      // output_ size
-  int pos_;       // current printing position
+  int num_prints_;
+  IncrementalStringBuilder builder_;
   int position_;  // position of ast node to print
   bool found_;
   bool done_;
   bool is_builtin_;
 
   DEFINE_AST_VISITOR_SUBCLASS_MEMBERS();
 
  protected:
   void PrintLiteral(Object* value, bool quote);
   void PrintLiteral(const AstRawString* value, bool quote);
@@ skipping 59 matching lines @@
   int pos_;       // current printing position
   int indent_;
 };
 
 #endif  // DEBUG
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_AST_PRETTYPRINTER_H_