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// Copyright (c) 2013 The Chromium 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 TOOLS_GN_ERR_H_
#define TOOLS_GN_ERR_H_
#include <string>
#include <vector>
#include "gn/location.h"
#include "gn/token.h"
class ParseNode;
class Value;
// Result of doing some operation. Check has_error() to see if an error
// occurred.
//
// An error has a location and a message. Below that, is some optional help
// text to go with the annotation of the location.
//
// An error can also have sub-errors which are additionally printed out
// below. They can provide additional context.
class Err {
public:
using RangeList = std::vector<LocationRange>;
// Indicates no error.
Err();
// Error at a single point.
Err(const Location& location,
const std::string& msg,
const std::string& help = std::string());
// Error at a given range.
Err(const LocationRange& range,
const std::string& msg,
const std::string& help = std::string());
// Error at a given token.
Err(const Token& token,
const std::string& msg,
const std::string& help_text = std::string());
// Error at a given node.
Err(const ParseNode* node,
const std::string& msg,
const std::string& help_text = std::string());
// Error at a given value.
Err(const Value& value,
const std::string msg,
const std::string& help_text = std::string());
Err(const Err& other);
~Err();
bool has_error() const { return has_error_; }
const Location& location() const { return location_; }
const std::string& message() const { return message_; }
const std::string& help_text() const { return help_text_; }
void AppendRange(const LocationRange& range) { ranges_.push_back(range); }
const RangeList& ranges() const { return ranges_; }
void AppendSubErr(const Err& err);
void PrintToStdout() const;
// Prints to standard out but uses a "WARNING" messaging instead of the
// normal "ERROR" messaging. This is a property of the printing system rather
// than of the Err class because there is no expectation that code calling a
// function that take an Err check that the error is nonfatal and continue.
// Generally all Err objects with has_error() set are fatal.
//
// In some very specific cases code will detect a condition and print a
// nonfatal error to the screen instead of returning it. In these cases, that
// code can decide at printing time whether it will continue (and use this
// method) or not (and use PrintToStdout()).
void PrintNonfatalToStdout() const;
private:
void InternalPrintToStdout(bool is_sub_err, bool is_fatal) const;
bool has_error_;
Location location_;
std::vector<LocationRange> ranges_;
std::string message_;
std::string help_text_;
std::vector<Err> sub_errs_;
};
#endif // TOOLS_GN_ERR_H_