nix-super/src/libexpr/eval-error.hh
Eelco Dolstra 2c88930ef2 AttrCursor: Remove forceErrors
Instead, force evaluation of the original value only if we need to
show the exception to the user.
2024-05-24 16:34:57 +02:00

103 lines
2.6 KiB
C++

#pragma once
#include <algorithm>
#include "error.hh"
#include "pos-idx.hh"
namespace nix {
struct Env;
struct Expr;
struct Value;
class EvalState;
template<class T>
class EvalErrorBuilder;
class EvalError : public Error
{
template<class T>
friend class EvalErrorBuilder;
public:
EvalState & state;
EvalError(EvalState & state, ErrorInfo && errorInfo)
: Error(errorInfo)
, state(state)
{
}
template<typename... Args>
explicit EvalError(EvalState & state, const std::string & formatString, const Args &... formatArgs)
: Error(formatString, formatArgs...)
, state(state)
{
}
};
MakeError(ParseError, Error);
MakeError(AssertionError, EvalError);
MakeError(ThrownError, AssertionError);
MakeError(Abort, EvalError);
MakeError(TypeError, EvalError);
MakeError(UndefinedVarError, EvalError);
MakeError(MissingArgumentError, EvalError);
MakeError(InfiniteRecursionError, EvalError);
struct InvalidPathError : public EvalError
{
public:
Path path;
InvalidPathError(EvalState & state, const Path & path)
: EvalError(state, "path '%s' is not valid", path)
{
}
};
/**
* `EvalErrorBuilder`s may only be constructed by `EvalState`. The `debugThrow`
* method must be the final method in any such `EvalErrorBuilder` usage, and it
* handles deleting the object.
*/
template<class T>
class EvalErrorBuilder final
{
friend class EvalState;
template<typename... Args>
explicit EvalErrorBuilder(EvalState & state, const Args &... args)
: error(T(state, args...))
{
}
public:
T error;
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> & withExitStatus(unsigned int exitStatus);
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> & atPos(PosIdx pos);
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> & atPos(Value & value, PosIdx fallback = noPos);
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> & withTrace(PosIdx pos, const std::string_view text);
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> & withFrameTrace(PosIdx pos, const std::string_view text);
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> & withSuggestions(Suggestions & s);
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> & withFrame(const Env & e, const Expr & ex);
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> & addTrace(PosIdx pos, HintFmt hint);
template<typename... Args>
[[nodiscard, gnu::noinline]] EvalErrorBuilder<T> &
addTrace(PosIdx pos, std::string_view formatString, const Args &... formatArgs);
/**
* Delete the `EvalErrorBuilder` and throw the underlying exception.
*/
[[gnu::noinline, gnu::noreturn]] void debugThrow();
};
}