messages.h

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// Copyright 2006-2008 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_EXECUTION_MESSAGES_H_
#define V8_EXECUTION_MESSAGES_H_
 
// The infrastructure used for (localized) message reporting in V8.
//
// Note: there's a big unresolved issue about ownership of the data
// structures used by this framework.
 
#include <memory>
 
#include "include/v8-local-handle.h"
#include "src/base/vector.h"
#include "src/common/message-template.h"
#include "src/handles/handles.h"
#include "src/handles/maybe-handles.h"
 
namespace v8 {
class Value;
 
namespace internal {
 
// Forward declarations.
class AbstractCode;
class JSMessageObject;
class LookupIterator;
class PrimitiveHeapObject;
class SharedFunctionInfo;
class SourceInfo;
class StackTraceInfo;
class WasmInstanceObject;
 
class V8_EXPORT_PRIVATE MessageLocation {
 public:
  // Constructors for when source positions are already known.
  // TODO(delphick): Collapse to a single constructor with a default parameter
  // when we stop using the GCC that requires this separation.
  MessageLocation(Handle<Script> script, int start_pos, int end_pos);
  MessageLocation(Handle<Script> script, int start_pos, int end_pos,
                  Handle<SharedFunctionInfo> shared);
  // Constructor for when source positions were not collected but which can be
  // reconstructed from the SharedFunctionInfo and bytecode offset.
  MessageLocation(Handle<Script> script, Handle<SharedFunctionInfo> shared,
                  int bytecode_offset);
  MessageLocation();
 
  Handle<Script> script() const { return script_; }
  int start_pos() const { return start_pos_; }
  int end_pos() const { return end_pos_; }
  int bytecode_offset() const { return bytecode_offset_; }
  Handle<SharedFunctionInfo> shared() const { return shared_; }
 
 private:
  Handle<Script> script_;
  int start_pos_;
  int end_pos_;
  int bytecode_offset_;
  Handle<SharedFunctionInfo> shared_;
};
 
// Determines how stack trace collection skips frames.
enum FrameSkipMode {
  // Unconditionally skips the first frame. Used e.g. when the Error constructor
  // is called, in which case the first frame is always a BUILTIN_EXIT frame.
  SKIP_FIRST,
  // Skip all frames until a specified caller function is seen.
  SKIP_UNTIL_SEEN,
  SKIP_NONE,
};
 
class ErrorUtils : public AllStatic {
 public:
  // |kDisabled| is useful when you don't need the stack information at all, for
  // example when creating a deserialized error.
  enum class StackTraceCollection { kEnabled, kDisabled };
  static MaybeDirectHandle<JSObject> Construct(Isolate* isolate,
                                               DirectHandle<JSFunction> target,
                                               DirectHandle<Object> new_target,
                                               DirectHandle<Object> message,
                                               DirectHandle<Object> options);
  static MaybeHandle<JSObject> Construct(
      Isolate* isolate, DirectHandle<JSFunction> target,
      DirectHandle<Object> new_target, DirectHandle<Object> message,
      DirectHandle<Object> options, FrameSkipMode mode,
      DirectHandle<Object> caller, StackTraceCollection stack_trace_collection);
 
  enum class ToStringMessageSource {
    kPreferOriginalMessage,
    kCurrentMessageProperty
  };
  V8_EXPORT_PRIVATE static MaybeHandle<String> ToString(
      Isolate* isolate, DirectHandle<Object> recv,
      ToStringMessageSource message_source =
          ToStringMessageSource::kCurrentMessageProperty);
 
  static Handle<JSObject> MakeGenericError(
      Isolate* isolate, DirectHandle<JSFunction> constructor,
      MessageTemplate index, base::Vector<const DirectHandle<Object>> args,
      FrameSkipMode mode);
 
  static DirectHandle<JSObject> ShadowRealmConstructTypeErrorCopy(
      Isolate* isolate, DirectHandle<Object> original, MessageTemplate index,
      base::Vector<const DirectHandle<Object>> args);
 
  // Formats a textual stack trace from the given structured stack trace.
  // Note that this can call arbitrary JS code through Error.prepareStackTrace.
  static MaybeDirectHandle<Object> FormatStackTrace(
      Isolate* isolate, DirectHandle<JSObject> error,
      DirectHandle<Object> stack_trace);
 
  static DirectHandle<JSObject> NewIteratorError(Isolate* isolate,
                                                 DirectHandle<Object> source);
  static DirectHandle<JSObject> NewCalledNonCallableError(
      Isolate* isolate, DirectHandle<Object> source);
  static DirectHandle<JSObject> NewConstructedNonConstructable(
      Isolate* isolate, DirectHandle<Object> source);
  // Returns the Exception sentinel.
  static Tagged<Object> ThrowSpreadArgError(Isolate* isolate,
                                            MessageTemplate id,
                                            DirectHandle<Object> object);
  // Returns the Exception sentinel.
  static Tagged<Object> ThrowLoadFromNullOrUndefined(
      Isolate* isolate, DirectHandle<Object> object,
      MaybeDirectHandle<Object> key);
 
  // Returns true if given object has own |error_stack_symbol| property.
  static bool HasErrorStackSymbolOwnProperty(Isolate* isolate,
                                             DirectHandle<JSObject> object);
 
  struct StackPropertyLookupResult {
    // The holder of the |error_stack_symbol| or empty handle.
    MaybeDirectHandle<JSObject> error_stack_symbol_holder;
    // The value of the |error_stack_symbol| property or |undefined_value|.
    Handle<Object> error_stack;
  };
  // Gets |error_stack_symbol| property value by looking up the prototype chain.
  static StackPropertyLookupResult GetErrorStackProperty(
      Isolate* isolate, DirectHandle<JSReceiver> maybe_error_object);
 
  static MaybeDirectHandle<Object> GetFormattedStack(
      Isolate* isolate, DirectHandle<JSObject> maybe_error_object);
  static void SetFormattedStack(Isolate* isolate,
                                DirectHandle<JSObject> maybe_error_object,
                                DirectHandle<Object> formatted_stack);
 
  // Collects the stack trace and installs the stack property accessors.
  static MaybeHandle<Object> CaptureStackTrace(Isolate* isolate,
                                               DirectHandle<JSObject> object,
                                               FrameSkipMode mode,
                                               Handle<Object> caller);
};
 
class MessageFormatter {
 public:
  V8_EXPORT_PRIVATE static const char* TemplateString(MessageTemplate index);
 
  V8_EXPORT_PRIVATE static MaybeHandle<String> TryFormat(
      Isolate* isolate, MessageTemplate index,
      base::Vector<const DirectHandle<String>> args);
 
  static DirectHandle<String> Format(
      Isolate* isolate, MessageTemplate index,
      base::Vector<const DirectHandle<Object>> args);
};
 
// A message handler is a convenience interface for accessing the list
// of message listeners registered in an environment
class MessageHandler {
 public:
  // Returns a message object for the API to use.
  V8_EXPORT_PRIVATE static Handle<JSMessageObject> MakeMessageObject(
      Isolate* isolate, MessageTemplate type, const MessageLocation* location,
      DirectHandle<Object> argument,
      DirectHandle<StackTraceInfo> stack_trace =
          DirectHandle<StackTraceInfo>::null());
 
  // Report a formatted message (needs JS allocation).
  V8_EXPORT_PRIVATE static void ReportMessage(
      Isolate* isolate, const MessageLocation* loc,
      DirectHandle<JSMessageObject> message);
 
  static void DefaultMessageReport(Isolate* isolate, const MessageLocation* loc,
                                   DirectHandle<Object> message_obj);
  static DirectHandle<String> GetMessage(Isolate* isolate,
                                         DirectHandle<Object> data);
  static std::unique_ptr<char[]> GetLocalizedMessage(Isolate* isolate,
                                                     DirectHandle<Object> data);
 
 private:
  static void ReportMessageNoExceptions(Isolate* isolate,
                                        const MessageLocation* loc,
                                        DirectHandle<Object> message_obj,
                                        Local<Value> api_exception_obj);
};
 
}  // namespace internal
}  // namespace v8
 
#endif  // V8_EXECUTION_MESSAGES_H_