// 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 #include #include "tools/gn/location.h" #include "tools/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; // 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 ranges_; std::string message_; std::string help_text_; std::vector sub_errs_; }; #endif // TOOLS_GN_ERR_H_