diff options
Diffstat (limited to 'src/libexpr/eval.cc')
| -rw-r--r-- | src/libexpr/eval.cc | 584 |
1 files changed, 260 insertions, 324 deletions
diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc index 9bc20a502..1828b8c2e 100644 --- a/src/libexpr/eval.cc +++ b/src/libexpr/eval.cc @@ -11,7 +11,9 @@ #include <algorithm> #include <chrono> +#include <iostream> #include <cstring> +#include <optional> #include <unistd.h> #include <sys/time.h> #include <sys/resource.h> @@ -318,7 +320,7 @@ static Symbol getName(const AttrName & name, EvalState & state, Env & env) } else { Value nameValue; name.expr->eval(state, env, nameValue); - state.forceStringNoCtx(nameValue); + state.forceStringNoCtx(nameValue, noPos, "while evaluating an attribute name"); return state.symbols.create(nameValue.string.s); } } @@ -414,6 +416,44 @@ static Strings parseNixPath(const std::string & s) return res; } +ErrorBuilder & ErrorBuilder::atPos(PosIdx pos) +{ + info.errPos = state.positions[pos]; + return *this; +} + +ErrorBuilder & ErrorBuilder::withTrace(PosIdx pos, const std::string_view text) +{ + info.traces.push_front(Trace{ .pos = state.positions[pos], .hint = hintformat(std::string(text)), .frame = false }); + return *this; +} + +ErrorBuilder & ErrorBuilder::withFrameTrace(PosIdx pos, const std::string_view text) +{ + info.traces.push_front(Trace{ .pos = state.positions[pos], .hint = hintformat(std::string(text)), .frame = true }); + return *this; +} + +ErrorBuilder & ErrorBuilder::withSuggestions(Suggestions & s) +{ + info.suggestions = s; + return *this; +} + +ErrorBuilder & ErrorBuilder::withFrame(const Env & env, const Expr & expr) +{ + // NOTE: This is abusing side-effects. + // TODO: check compatibility with nested debugger calls. + state.debugTraces.push_front(DebugTrace { + .pos = nullptr, + .expr = expr, + .env = env, + .hint = hintformat("Fake frame for debugging purposes"), + .isError = true + }); + return *this; +} + EvalState::EvalState( const Strings & _searchPath, @@ -646,25 +686,7 @@ void EvalState::addConstant(const std::string & name, Value * v) Value * EvalState::addPrimOp(const std::string & name, size_t arity, PrimOpFun primOp) { - auto name2 = name.substr(0, 2) == "__" ? name.substr(2) : name; - auto sym = symbols.create(name2); - - /* Hack to make constants lazy: turn them into a application of - the primop to a dummy value. */ - if (arity == 0) { - auto vPrimOp = allocValue(); - vPrimOp->mkPrimOp(new PrimOp { .fun = primOp, .arity = 1, .name = name2 }); - Value v; - v.mkApp(vPrimOp, vPrimOp); - return addConstant(name, v); - } - - Value * v = allocValue(); - v->mkPrimOp(new PrimOp { .fun = primOp, .arity = arity, .name = name2 }); - staticBaseEnv->vars.emplace_back(symbols.create(name), baseEnvDispl); - baseEnv.values[baseEnvDispl++] = v; - baseEnv.values[0]->attrs->push_back(Attr(sym, v)); - return v; + return addPrimOp(PrimOp { .fun = primOp, .arity = arity, .name = name }); } @@ -842,176 +864,14 @@ void EvalState::runDebugRepl(const Error * error, const Env & env, const Expr & } } -/* Every "format" object (even temporary) takes up a few hundred bytes - of stack space, which is a real killer in the recursive - evaluator. So here are some helper functions for throwing - exceptions. */ -void EvalState::throwEvalError(const PosIdx pos, const char * s, Env & env, Expr & expr) -{ - debugThrow(EvalError({ - .msg = hintfmt(s), - .errPos = positions[pos] - }), env, expr); -} - -void EvalState::throwEvalError(const PosIdx pos, const char * s) -{ - debugThrowLastTrace(EvalError({ - .msg = hintfmt(s), - .errPos = positions[pos] - })); -} - -void EvalState::throwEvalError(const char * s, const std::string & s2) -{ - debugThrowLastTrace(EvalError(s, s2)); -} - -void EvalState::throwEvalError(const PosIdx pos, const Suggestions & suggestions, const char * s, - const std::string & s2, Env & env, Expr & expr) -{ - debugThrow(EvalError(ErrorInfo{ - .msg = hintfmt(s, s2), - .errPos = positions[pos], - .suggestions = suggestions, - }), env, expr); -} - -void EvalState::throwEvalError(const PosIdx pos, const char * s, const std::string & s2) -{ - debugThrowLastTrace(EvalError({ - .msg = hintfmt(s, s2), - .errPos = positions[pos] - })); -} - -void EvalState::throwEvalError(const PosIdx pos, const char * s, const std::string & s2, Env & env, Expr & expr) -{ - debugThrow(EvalError({ - .msg = hintfmt(s, s2), - .errPos = positions[pos] - }), env, expr); -} - -void EvalState::throwEvalError(const char * s, const std::string & s2, - const std::string & s3) -{ - debugThrowLastTrace(EvalError({ - .msg = hintfmt(s, s2, s3), - .errPos = positions[noPos] - })); -} - -void EvalState::throwEvalError(const PosIdx pos, const char * s, const std::string & s2, - const std::string & s3) -{ - debugThrowLastTrace(EvalError({ - .msg = hintfmt(s, s2, s3), - .errPos = positions[pos] - })); -} - -void EvalState::throwEvalError(const PosIdx pos, const char * s, const std::string & s2, - const std::string & s3, Env & env, Expr & expr) -{ - debugThrow(EvalError({ - .msg = hintfmt(s, s2, s3), - .errPos = positions[pos] - }), env, expr); -} - -void EvalState::throwEvalError(const PosIdx p1, const char * s, const Symbol sym, const PosIdx p2, Env & env, Expr & expr) -{ - // p1 is where the error occurred; p2 is a position mentioned in the message. - debugThrow(EvalError({ - .msg = hintfmt(s, symbols[sym], positions[p2]), - .errPos = positions[p1] - }), env, expr); -} - -void EvalState::throwTypeError(const PosIdx pos, const char * s, const Value & v) -{ - debugThrowLastTrace(TypeError({ - .msg = hintfmt(s, showType(v)), - .errPos = positions[pos] - })); -} - -void EvalState::throwTypeError(const PosIdx pos, const char * s, const Value & v, Env & env, Expr & expr) -{ - debugThrow(TypeError({ - .msg = hintfmt(s, showType(v)), - .errPos = positions[pos] - }), env, expr); -} - -void EvalState::throwTypeError(const PosIdx pos, const char * s) -{ - debugThrowLastTrace(TypeError({ - .msg = hintfmt(s), - .errPos = positions[pos] - })); -} - -void EvalState::throwTypeError(const PosIdx pos, const char * s, const ExprLambda & fun, - const Symbol s2, Env & env, Expr &expr) -{ - debugThrow(TypeError({ - .msg = hintfmt(s, fun.showNamePos(*this), symbols[s2]), - .errPos = positions[pos] - }), env, expr); -} - -void EvalState::throwTypeError(const PosIdx pos, const Suggestions & suggestions, const char * s, - const ExprLambda & fun, const Symbol s2, Env & env, Expr &expr) -{ - debugThrow(TypeError(ErrorInfo { - .msg = hintfmt(s, fun.showNamePos(*this), symbols[s2]), - .errPos = positions[pos], - .suggestions = suggestions, - }), env, expr); -} - -void EvalState::throwTypeError(const char * s, const Value & v, Env & env, Expr &expr) -{ - debugThrow(TypeError({ - .msg = hintfmt(s, showType(v)), - .errPos = positions[expr.getPos()], - }), env, expr); -} - -void EvalState::throwAssertionError(const PosIdx pos, const char * s, const std::string & s1, Env & env, Expr &expr) -{ - debugThrow(AssertionError({ - .msg = hintfmt(s, s1), - .errPos = positions[pos] - }), env, expr); -} - -void EvalState::throwUndefinedVarError(const PosIdx pos, const char * s, const std::string & s1, Env & env, Expr &expr) -{ - debugThrow(UndefinedVarError({ - .msg = hintfmt(s, s1), - .errPos = positions[pos] - }), env, expr); -} - -void EvalState::throwMissingArgumentError(const PosIdx pos, const char * s, const std::string & s1, Env & env, Expr &expr) -{ - debugThrow(MissingArgumentError({ - .msg = hintfmt(s, s1), - .errPos = positions[pos] - }), env, expr); -} - void EvalState::addErrorTrace(Error & e, const char * s, const std::string & s2) const { e.addTrace(nullptr, s, s2); } -void EvalState::addErrorTrace(Error & e, const PosIdx pos, const char * s, const std::string & s2) const +void EvalState::addErrorTrace(Error & e, const PosIdx pos, const char * s, const std::string & s2, bool frame) const { - e.addTrace(positions[pos], s, s2); + e.addTrace(positions[pos], hintfmt(s, s2), frame); } static std::unique_ptr<DebugTraceStacker> makeDebugTraceStacker( @@ -1088,7 +948,7 @@ inline Value * EvalState::lookupVar(Env * env, const ExprVar & var, bool noEval) if (env->type == Env::HasWithExpr) { if (noEval) return 0; Value * v = allocValue(); - evalAttrs(*env->up, (Expr *) env->values[0], *v); + evalAttrs(*env->up, (Expr *) env->values[0], *v, noPos, "<borked>"); env->values[0] = v; env->type = Env::HasWithAttrs; } @@ -1098,7 +958,7 @@ inline Value * EvalState::lookupVar(Env * env, const ExprVar & var, bool noEval) return j->value; } if (!env->prevWith) - throwUndefinedVarError(var.pos, "undefined variable '%1%'", symbols[var.name], *env, const_cast<ExprVar&>(var)); + error("undefined variable '%1%'", symbols[var.name]).atPos(var.pos).withFrame(*env, var).debugThrow<UndefinedVarError>(); for (size_t l = env->prevWith; l; --l, env = env->up) ; } } @@ -1248,7 +1108,7 @@ void EvalState::cacheFile( // computation. if (mustBeTrivial && !(dynamic_cast<ExprAttrs *>(e))) - throw EvalError("file '%s' must be an attribute set", path); + error("file '%s' must be an attribute set", path).debugThrow<EvalError>(); eval(e, v); } catch (Error & e) { addErrorTrace(e, "while evaluating the file '%1%':", resolvedPath); @@ -1266,31 +1126,31 @@ void EvalState::eval(Expr * e, Value & v) } -inline bool EvalState::evalBool(Env & env, Expr * e) +inline bool EvalState::evalBool(Env & env, Expr * e, const PosIdx pos, std::string_view errorCtx) { - Value v; - e->eval(*this, env, v); - if (v.type() != nBool) - throwTypeError(noPos, "value is %1% while a Boolean was expected", v, env, *e); - return v.boolean; -} - - -inline bool EvalState::evalBool(Env & env, Expr * e, const PosIdx pos) -{ - Value v; - e->eval(*this, env, v); - if (v.type() != nBool) - throwTypeError(pos, "value is %1% while a Boolean was expected", v, env, *e); - return v.boolean; + try { + Value v; + e->eval(*this, env, v); + if (v.type() != nBool) + error("value is %1% while a Boolean was expected", showType(v)).withFrame(env, *e).debugThrow<TypeError>(); + return v.boolean; + } catch (Error & e) { + e.addTrace(positions[pos], errorCtx); + throw; + } } -inline void EvalState::evalAttrs(Env & env, Expr * e, Value & v) +inline void EvalState::evalAttrs(Env & env, Expr * e, Value & v, const PosIdx pos, std::string_view errorCtx) { - e->eval(*this, env, v); - if (v.type() != nAttrs) - throwTypeError(noPos, "value is %1% while a set was expected", v, env, *e); + try { + e->eval(*this, env, v); + if (v.type() != nAttrs) + error("value is %1% while a set was expected", showType(v)).withFrame(env, *e).debugThrow<TypeError>(); + } catch (Error & e) { + e.addTrace(positions[pos], errorCtx); + throw; + } } @@ -1363,7 +1223,7 @@ void ExprAttrs::eval(EvalState & state, Env & env, Value & v) Hence we need __overrides.) */ if (hasOverrides) { Value * vOverrides = (*v.attrs)[overrides->second.displ].value; - state.forceAttrs(*vOverrides, [&]() { return vOverrides->determinePos(noPos); }); + state.forceAttrs(*vOverrides, [&]() { return vOverrides->determinePos(noPos); }, "while evaluating the `__overrides` attribute"); Bindings * newBnds = state.allocBindings(v.attrs->capacity() + vOverrides->attrs->size()); for (auto & i : *v.attrs) newBnds->push_back(i); @@ -1391,11 +1251,11 @@ void ExprAttrs::eval(EvalState & state, Env & env, Value & v) state.forceValue(nameVal, i.pos); if (nameVal.type() == nNull) continue; - state.forceStringNoCtx(nameVal); + state.forceStringNoCtx(nameVal, i.pos, "while evaluating the name of a dynamic attribute"); auto nameSym = state.symbols.create(nameVal.string.s); Bindings::iterator j = v.attrs->find(nameSym); if (j != v.attrs->end()) - state.throwEvalError(i.pos, "dynamic attribute '%1%' already defined at %2%", nameSym, j->pos, env, *this); + state.error("dynamic attribute '%1%' already defined at %2%", state.symbols[nameSym], state.positions[j->pos]).atPos(i.pos).withFrame(env, *this).debugThrow<EvalError>(); i.valueExpr->setName(nameSym); /* Keep sorted order so find can catch duplicates */ @@ -1492,15 +1352,14 @@ void ExprSelect::eval(EvalState & state, Env & env, Value & v) return; } } else { - state.forceAttrs(*vAttrs, pos); + state.forceAttrs(*vAttrs, pos, "while selecting an attribute"); if ((j = vAttrs->attrs->find(name)) == vAttrs->attrs->end()) { std::set<std::string> allAttrNames; for (auto & attr : *vAttrs->attrs) allAttrNames.insert(state.symbols[attr.name]); - state.throwEvalError( - pos, - Suggestions::bestMatches(allAttrNames, state.symbols[name]), - "attribute '%1%' missing", state.symbols[name], env, *this); + auto suggestions = Suggestions::bestMatches(allAttrNames, state.symbols[name]); + state.error("attribute '%1%' missing", state.symbols[name]) + .atPos(pos).withSuggestions(suggestions).withFrame(env, *this).debugThrow<EvalError>(); } } vAttrs = j->value; @@ -1595,7 +1454,12 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value & if (!lambda.hasFormals()) env2.values[displ++] = args[0]; else { - forceAttrs(*args[0], pos); + try { + forceAttrs(*args[0], lambda.pos, "while evaluating the value passed for the lambda argument"); + } catch (Error & e) { + if (pos) e.addTrace(positions[pos], "from call site"); + throw; + } if (lambda.arg) env2.values[displ++] = args[0]; @@ -1607,8 +1471,15 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value & for (auto & i : lambda.formals->formals) { auto j = args[0]->attrs->get(i.name); if (!j) { - if (!i.def) throwTypeError(pos, "%1% called without required argument '%2%'", - lambda, i.name, *fun.lambda.env, lambda); + if (!i.def) { + error("function '%1%' called without required argument '%2%'", + (lambda.name ? std::string(symbols[lambda.name]) : "anonymous lambda"), + symbols[i.name]) + .atPos(lambda.pos) + .withTrace(pos, "from call site") + .withFrame(*fun.lambda.env, lambda) + .debugThrow<TypeError>(); + } env2.values[displ++] = i.def->maybeThunk(*this, env2); } else { attrsUsed++; @@ -1626,11 +1497,15 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value & std::set<std::string> formalNames; for (auto & formal : lambda.formals->formals) formalNames.insert(symbols[formal.name]); - throwTypeError( - pos, - Suggestions::bestMatches(formalNames, symbols[i.name]), - "%1% called with unexpected argument '%2%'", - lambda, i.name, *fun.lambda.env, lambda); + auto suggestions = Suggestions::bestMatches(formalNames, symbols[i.name]); + error("function '%1%' called with unexpected argument '%2%'", + (lambda.name ? std::string(symbols[lambda.name]) : "anonymous lambda"), + symbols[i.name]) + .atPos(lambda.pos) + .withTrace(pos, "from call site") + .withSuggestions(suggestions) + .withFrame(*fun.lambda.env, lambda) + .debugThrow<TypeError>(); } abort(); // can't happen } @@ -1653,11 +1528,15 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value & lambda.body->eval(*this, env2, vCur); } catch (Error & e) { if (loggerSettings.showTrace.get()) { - addErrorTrace(e, lambda.pos, "while calling %s", - (lambda.name - ? concatStrings("'", symbols[lambda.name], "'") - : "anonymous lambda")); - addErrorTrace(e, pos, "while evaluating call site%s", ""); + addErrorTrace( + e, + lambda.pos, + "while calling %s", + lambda.name + ? concatStrings("'", symbols[lambda.name], "'") + : "anonymous lambda", + true); + if (pos) addErrorTrace(e, pos, "from call site%s", "", true); } throw; } @@ -1676,9 +1555,17 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value & return; } else { /* We have all the arguments, so call the primop. */ + auto name = vCur.primOp->name; + nrPrimOpCalls++; - if (countCalls) primOpCalls[vCur.primOp->name]++; - vCur.primOp->fun(*this, pos, args, vCur); + if (countCalls) primOpCalls[name]++; + + try { + vCur.primOp->fun(*this, noPos, args, vCur); + } catch (Error & e) { + addErrorTrace(e, pos, "while calling the '%1%' builtin", name); + throw; + } nrArgs -= argsLeft; args += argsLeft; @@ -1713,9 +1600,20 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value & for (size_t i = 0; i < argsLeft; ++i) vArgs[argsDone + i] = args[i]; + auto name = primOp->primOp->name; nrPrimOpCalls++; - if (countCalls) primOpCalls[primOp->primOp->name]++; - primOp->primOp->fun(*this, pos, vArgs, vCur); + if (countCalls) primOpCalls[name]++; + + try { + // TODO: + // 1. Unify this and above code. Heavily redundant. + // 2. Create a fake env (arg1, arg2, etc.) and a fake expr (arg1: arg2: etc: builtins.name arg1 arg2 etc) + // so the debugger allows to inspect the wrong parameters passed to the builtin. + primOp->primOp->fun(*this, noPos, vArgs, vCur); + } catch (Error & e) { + addErrorTrace(e, pos, "while calling the '%1%' builtin", name); + throw; + } nrArgs -= argsLeft; args += argsLeft; @@ -1728,14 +1626,18 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value & heap-allocate a copy and use that instead. */ Value * args2[] = {allocValue(), args[0]}; *args2[0] = vCur; - /* !!! Should we use the attr pos here? */ - callFunction(*functor->value, 2, args2, vCur, pos); + try { + callFunction(*functor->value, 2, args2, vCur, functor->pos); + } catch (Error & e) { + e.addTrace(positions[pos], "while calling a functor (an attribute set with a '__functor' attribute)"); + throw; + } nrArgs--; args++; } else - throwTypeError(pos, "attempt to call something which is not a function but %1%", vCur); + error("attempt to call something which is not a function but %1%", showType(vCur)).atPos(pos).debugThrow<TypeError>(); } vRes = vCur; @@ -1799,13 +1701,12 @@ void EvalState::autoCallFunction(Bindings & args, Value & fun, Value & res) if (j != args.end()) { attrs.insert(*j); } else if (!i.def) { - throwMissingArgumentError(i.pos, R"(cannot evaluate a function that has an argument without a value ('%1%') - + error(R"(cannot evaluate a function that has an argument without a value ('%1%') Nix attempted to evaluate a function as a top level expression; in this case it must have its arguments supplied either by default values, or passed explicitly with '--arg' or '--argstr'. See -https://nixos.org/manual/nix/stable/language/constructs.html#functions.)", symbols[i.name], - *fun.lambda.env, *fun.lambda.fun); +https://nixos.org/manual/nix/stable/language/constructs.html#functions.)", symbols[i.name]) + .atPos(i.pos).withFrame(*fun.lambda.env, *fun.lambda.fun).debugThrow<MissingArgumentError>(); } } } @@ -1828,16 +1729,17 @@ void ExprWith::eval(EvalState & state, Env & env, Value & v) void ExprIf::eval(EvalState & state, Env & env, Value & v) { - (state.evalBool(env, cond, pos) ? then : else_)->eval(state, env, v); + // We cheat in the parser, and pass the position of the condition as the position of the if itself. + (state.evalBool(env, cond, pos, "while evaluating a branch condition") ? then : else_)->eval(state, env, v); } void ExprAssert::eval(EvalState & state, Env & env, Value & v) { - if (!state.evalBool(env, cond, pos)) { + if (!state.evalBool(env, cond, pos, "in the condition of the assert statement")) { std::ostringstream out; cond->show(state.symbols, out); - state.throwAssertionError(pos, "assertion '%1%' failed", out.str(), env, *this); + state.error("assertion '%1%' failed", out.str()).atPos(pos).withFrame(env, *this).debugThrow<AssertionError>(); } body->eval(state, env, v); } @@ -1845,7 +1747,7 @@ void ExprAssert::eval(EvalState & state, Env & env, Value & v) void ExprOpNot::eval(EvalState & state, Env & env, Value & v) { - v.mkBool(!state.evalBool(env, e)); + v.mkBool(!state.evalBool(env, e, noPos, "in the argument of the not operator")); // XXX: FIXME: ! } @@ -1853,7 +1755,7 @@ void ExprOpEq::eval(EvalState & state, Env & env, Value & v) { Value v1; e1->eval(state, env, v1); Value v2; e2->eval(state, env, v2); - v.mkBool(state.eqValues(v1, v2)); + v.mkBool(state.eqValues(v1, v2, pos, "while testing two values for equality")); } @@ -1861,33 +1763,33 @@ void ExprOpNEq::eval(EvalState & state, Env & env, Value & v) { Value v1; e1->eval(state, env, v1); Value v2; e2->eval(state, env, v2); - v.mkBool(!state.eqValues(v1, v2)); + v.mkBool(!state.eqValues(v1, v2, pos, "while testing two values for inequality")); } void ExprOpAnd::eval(EvalState & state, Env & env, Value & v) { - v.mkBool(state.evalBool(env, e1, pos) && state.evalBool(env, e2, pos)); + v.mkBool(state.evalBool(env, e1, pos, "in the left operand of the AND (&&) operator") && state.evalBool(env, e2, pos, "in the right operand of the AND (&&) operator")); } void ExprOpOr::eval(EvalState & state, Env & env, Value & v) { - v.mkBool(state.evalBool(env, e1, pos) || state.evalBool(env, e2, pos)); + v.mkBool(state.evalBool(env, e1, pos, "in the left operand of the OR (||) operator") || state.evalBool(env, e2, pos, "in the right operand of the OR (||) operator")); } void ExprOpImpl::eval(EvalState & state, Env & env, Value & v) { - v.mkBool(!state.evalBool(env, e1, pos) || state.evalBool(env, e2, pos)); + v.mkBool(!state.evalBool(env, e1, pos, "in the left operand of the IMPL (->) operator") || state.evalBool(env, e2, pos, "in the right operand of the IMPL (->) operator")); } void ExprOpUpdate::eval(EvalState & state, Env & env, Value & v) { Value v1, v2; - state.evalAttrs(env, e1, v1); - state.evalAttrs(env, e2, v2); + state.evalAttrs(env, e1, v1, pos, "in the left operand of the update (//) operator"); + state.evalAttrs(env, e2, v2, pos, "in the right operand of the update (//) operator"); state.nrOpUpdates++; @@ -1926,18 +1828,18 @@ void ExprOpConcatLists::eval(EvalState & state, Env & env, Value & v) Value v1; e1->eval(state, env, v1); Value v2; e2->eval(state, env, v2); Value * lists[2] = { &v1, &v2 }; - state.concatLists(v, 2, lists, pos); + state.concatLists(v, 2, lists, pos, "while evaluating one of the elements to concatenate"); } -void EvalState::concatLists(Value & v, size_t nrLists, Value * * lists, const PosIdx pos) +void EvalState::concatLists(Value & v, size_t nrLists, Value * * lists, const PosIdx pos, std::string_view errorCtx) { nrListConcats++; Value * nonEmpty = 0; size_t len = 0; for (size_t n = 0; n < nrLists; ++n) { - forceList(*lists[n], pos); + forceList(*lists[n], pos, errorCtx); auto l = lists[n]->listSize(); len += l; if (l) nonEmpty = lists[n]; @@ -2014,20 +1916,22 @@ void ExprConcatStrings::eval(EvalState & state, Env & env, Value & v) nf = n; nf += vTmp.fpoint; } else - state.throwEvalError(i_pos, "cannot add %1% to an integer", showType(vTmp), env, *this); + state.error("cannot add %1% to an integer", showType(vTmp)).atPos(i_pos).withFrame(env, *this).debugThrow<EvalError>(); } else if (firstType == nFloat) { if (vTmp.type() == nInt) { nf += vTmp.integer; } else if (vTmp.type() == nFloat) { nf += vTmp.fpoint; } else - state.throwEvalError(i_pos, "cannot add %1% to a float", showType(vTmp), env, *this); + state.error("cannot add %1% to a float", showType(vTmp)).atPos(i_pos).withFrame(env, *this).debugThrow<EvalError>(); } else { if (s.empty()) s.reserve(es->size()); /* skip canonization of first path, which would only be not canonized in the first place if it's coming from a ./${foo} type path */ - auto part = state.coerceToString(i_pos, vTmp, context, false, firstType == nString, !first); + auto part = state.coerceToString(i_pos, vTmp, context, + "while evaluating a path segment", + false, firstType == nString, !first); sSize += part->size(); s.emplace_back(std::move(part)); } @@ -2041,7 +1945,7 @@ void ExprConcatStrings::eval(EvalState & state, Env & env, Value & v) v.mkFloat(nf); else if (firstType == nPath) { if (!context.empty()) - state.throwEvalError(pos, "a string that refers to a store path cannot be appended to a path", env, *this); + state.error("a string that refers to a store path cannot be appended to a path").atPos(pos).withFrame(env, *this).debugThrow<EvalError>(); v.mkPath(canonPath(str())); } else v.mkStringMove(c_str(), context); @@ -2091,33 +1995,47 @@ void EvalState::forceValueDeep(Value & v) } -NixInt EvalState::forceInt(Value & v, const PosIdx pos) +NixInt EvalState::forceInt(Value & v, const PosIdx pos, std::string_view errorCtx) { - forceValue(v, pos); - if (v.type() != nInt) - throwTypeError(pos, "value is %1% while an integer was expected", v); - - return v.integer; + try { + forceValue(v, pos); + if (v.type() != nInt) + error("value is %1% while an integer was expected", showType(v)).debugThrow<TypeError>(); + return v.integer; + } catch (Error & e) { + e.addTrace(positions[pos], errorCtx); + throw; + } } -NixFloat EvalState::forceFloat(Value & v, const PosIdx pos) +NixFloat EvalState::forceFloat(Value & v, const PosIdx pos, std::string_view errorCtx) { - forceValue(v, pos); - if (v.type() == nInt) - return v.integer; - else if (v.type() != nFloat) - throwTypeError(pos, "value is %1% while a float was expected", v); - return v.fpoint; + try { + forceValue(v, pos); + if (v.type() == nInt) + return v.integer; + else if (v.type() != nFloat) + error("value is %1% while a float was expected", showType(v)).debugThrow<TypeError>(); + return v.fpoint; + } catch (Error & e) { + e.addTrace(positions[pos], errorCtx); + throw; + } } -bool EvalState::forceBool(Value & v, const PosIdx pos) +bool EvalState::forceBool(Value & v, const PosIdx pos, std::string_view errorCtx) { - forceValue(v, pos); - if (v.type() != nBool) - throwTypeError(pos, "value is %1% while a Boolean was expected", v); - return v.boolean; + try { + forceValue(v, pos); + if (v.type() != nBool) + error("value is %1% while a Boolean was expected", showType(v)).debugThrow<TypeError>(); + return v.boolean; + } catch (Error & e) { + e.addTrace(positions[pos], errorCtx); + throw; + } } @@ -2127,21 +2045,30 @@ bool EvalState::isFunctor(Value & fun) } -void EvalState::forceFunction(Value & v, const PosIdx pos) +void EvalState::forceFunction(Value & v, const PosIdx pos, std::string_view errorCtx) { - forceValue(v, pos); - if (v.type() != nFunction && !isFunctor(v)) - throwTypeError(pos, "value is %1% while a function was expected", v); + try { + forceValue(v, pos); + if (v.type() != nFunction && !isFunctor(v)) + error("value is %1% while a function was expected", showType(v)).debugThrow<TypeError>(); + } catch (Error & e) { + e.addTrace(positions[pos], errorCtx); + throw; + } } -std::string_view EvalState::forceString(Value & v, const PosIdx pos) +std::string_view EvalState::forceString(Value & v, const PosIdx pos, std::string_view errorCtx) { - forceValue(v, pos); - if (v.type() != nString) { - throwTypeError(pos, "value is %1% while a string was expected", v); + try { + forceValue(v, pos); + if (v.type() != nString) + error("value is %1% while a string was expected", showType(v)).debugThrow<TypeError>(); + return v.string.s; + } catch (Error & e) { + e.addTrace(positions[pos], errorCtx); + throw; } - return v.string.s; } @@ -2164,24 +2091,19 @@ NixStringContext Value::getContext(const Store & store) } -std::string_view EvalState::forceString(Value & v, PathSet & context, const PosIdx pos) +std::string_view EvalState::forceString(Value & v, PathSet & context, const PosIdx pos, std::string_view errorCtx) { - auto s = forceString(v, pos); + auto s = forceString(v, pos, errorCtx); copyContext(v, context); return s; } -std::string_view EvalState::forceStringNoCtx(Value & v, const PosIdx pos) +std::string_view EvalState::forceStringNoCtx(Value & v, const PosIdx pos, std::string_view errorCtx) { - auto s = forceString(v, pos); + auto s = forceString(v, pos, errorCtx); if (v.string.context) { - if (pos) - throwEvalError(pos, "the string '%1%' is not allowed to refer to a store path (such as '%2%')", - v.string.s, v.string.context[0]); - else - throwEvalError("the string '%1%' is not allowed to refer to a store path (such as '%2%')", - v.string.s, v.string.context[0]); + error("the string '%1%' is not allowed to refer to a store path (such as '%2%')", v.string.s, v.string.context[0]).withTrace(pos, errorCtx).debugThrow<EvalError>(); } return s; } @@ -2205,14 +2127,16 @@ std::optional<std::string> EvalState::tryAttrsToString(const PosIdx pos, Value & if (i != v.attrs->end()) { Value v1; callFunction(*i->value, v, v1, pos); - return coerceToString(pos, v1, context, coerceMore, copyToStore).toOwned(); + return coerceToString(pos, v1, context, + "while evaluating the result of the `__toString` attribute", + coerceMore, copyToStore).toOwned(); } return {}; } -BackedStringView EvalState::coerceToString(const PosIdx pos, Value & v, PathSet & context, - bool coerceMore, bool copyToStore, bool canonicalizePath) +BackedStringView EvalState::coerceToString(const PosIdx pos, Value &v, PathSet &context, + std::string_view errorCtx, bool coerceMore, bool copyToStore, bool canonicalizePath) { forceValue(v, pos); @@ -2235,13 +2159,23 @@ BackedStringView EvalState::coerceToString(const PosIdx pos, Value & v, PathSet if (maybeString) return std::move(*maybeString); auto i = v.attrs->find(sOutPath); - if (i == v.attrs->end()) - throwTypeError(pos, "cannot coerce a set to a string"); - return coerceToString(pos, *i->value, context, coerceMore, copyToStore); + if (i == v.attrs->end()) { + error("cannot coerce %1% to a string", showType(v)) + .withTrace(pos, errorCtx) + .debugThrow<TypeError>(); + } + return coerceToString(pos, *i->value, context, errorCtx, + coerceMore, copyToStore, canonicalizePath); } - if (v.type() == nExternal) - return v.external->coerceToString(positions[pos], context, coerceMore, copyToStore); + if (v.type() == nExternal) { + try { + return v.external->coerceToString(positions[pos], context, coerceMore, copyToStore); + } catch (Error & e) { + e.addTrace(nullptr, errorCtx); + throw; + } + } if (coerceMore) { /* Note that `false' is represented as an empty string for @@ -2255,7 +2189,14 @@ BackedStringView EvalState::coerceToString(const PosIdx pos, Value & v, PathSet if (v.isList()) { std::string result; for (auto [n, v2] : enumerate(v.listItems())) { - result += *coerceToString(pos, *v2, context, coerceMore, copyToStore); + try { + result += *coerceToString(noPos, *v2, context, + "while evaluating one element of the list", + coerceMore, copyToStore, canonicalizePath); + } catch (Error & e) { + e.addTrace(positions[pos], errorCtx); + throw; + } if (n < v.listSize() - 1 /* !!! not quite correct */ && (!v2->isList() || v2->listSize() != 0)) @@ -2265,14 +2206,16 @@ BackedStringView EvalState::coerceToString(const PosIdx pos, Value & v, PathSet } } - throwTypeError(pos, "cannot coerce %1% to a string", v); + error("cannot coerce %1% to a string", showType(v)) + .withTrace(pos, errorCtx) + .debugThrow<TypeError>(); } StorePath EvalState::copyPathToStore(PathSet & context, const Path & path) { if (nix::isDerivation(path)) - throwEvalError("file names are not allowed to end in '%1%'", drvExtension); + error("file names are not allowed to end in '%1%'", drvExtension).debugThrow<EvalError>(); auto dstPath = [&]() -> StorePath { @@ -2293,28 +2236,25 @@ StorePath EvalState::copyPathToStore(PathSet & context, const Path & path) } -Path EvalState::coerceToPath(const PosIdx pos, Value & v, PathSet & context) +Path EvalState::coerceToPath(const PosIdx pos, Value & v, PathSet & context, std::string_view errorCtx) { - auto path = coerceToString(pos, v, context, false, false).toOwned(); + auto path = coerceToString(pos, v, context, errorCtx, false, false, true).toOwned(); if (path == "" || path[0] != '/') - throwEvalError(pos, "string '%1%' doesn't represent an absolute path", path); + error("string '%1%' doesn't represent an absolute path", path).withTrace(pos, errorCtx).debugThrow<EvalError>(); return path; } -StorePath EvalState::coerceToStorePath(const PosIdx pos, Value & v, PathSet & context) +StorePath EvalState::coerceToStorePath(const PosIdx pos, Value & v, PathSet & context, std::string_view errorCtx) { - auto path = coerceToString(pos, v, context, false, false).toOwned(); + auto path = coerceToString(pos, v, context, errorCtx, false, false, true).toOwned(); if (auto storePath = store->maybeParseStorePath(path)) return *storePath; - throw EvalError({ - .msg = hintfmt("path '%1%' is not in the Nix store", path), - .errPos = positions[pos] - }); + error("path '%1%' is not in the Nix store", path).withTrace(pos, errorCtx).debugThrow<EvalError>(); } -bool EvalState::eqValues(Value & v1, Value & v2) +bool EvalState::eqValues(Value & v1, Value & v2, const PosIdx pos, std::string_view errorCtx) { forceValue(v1, noPos); forceValue(v2, noPos); @@ -2334,7 +2274,6 @@ bool EvalState::eqValues(Value & v1, Value & v2) if (v1.type() != v2.type()) return false; switch (v1.type()) { - case nInt: return v1.integer == v2.integer; @@ -2353,7 +2292,7 @@ bool EvalState::eqValues(Value & v1, Value & v2) case nList: if (v1.listSize() != v2.listSize()) return false; for (size_t n = 0; n < v1.listSize(); ++n) - if (!eqValues(*v1.listElems()[n], *v2.listElems()[n])) return false; + if (!eqValues(*v1.listElems()[n], *v2.listElems()[n], pos, errorCtx)) return false; return true; case nAttrs: { @@ -2363,7 +2302,7 @@ bool EvalState::eqValues(Value & v1, Value & v2) Bindings::iterator i = v1.attrs->find(sOutPath); Bindings::iterator j = v2.attrs->find(sOutPath); if (i != v1.attrs->end() && j != v2.attrs->end()) - return eqValues(*i->value, *j->value); + return eqValues(*i->value, *j->value, pos, errorCtx); } if (v1.attrs->size() != v2.attrs->size()) return false; @@ -2371,7 +2310,7 @@ bool EvalState::eqValues(Value & v1, Value & v2) /* Otherwise, compare the attributes one by one. */ Bindings::iterator i, j; for (i = v1.attrs->begin(), j = v2.attrs->begin(); i != v1.attrs->end(); ++i, ++j) - if (i->name != j->name || !eqValues(*i->value, *j->value)) + if (i->name != j->name || !eqValues(*i->value, *j->value, pos, errorCtx)) return false; return true; @@ -2388,9 +2327,7 @@ bool EvalState::eqValues(Value & v1, Value & v2) return v1.fpoint == v2.fpoint; default: - throwEvalError("cannot compare %1% with %2%", - showType(v1), - showType(v2)); + error("cannot compare %1% with %2%", showType(v1), showType(v2)).withTrace(pos, errorCtx).debugThrow<EvalError>(); } } @@ -2517,8 +2454,7 @@ void EvalState::printStats() std::string ExternalValueBase::coerceToString(const Pos & pos, PathSet & context, bool copyMore, bool copyToStore) const { throw TypeError({ - .msg = hintfmt("cannot coerce %1% to a string", showType()), - .errPos = pos + .msg = hintfmt("cannot coerce %1% to a string", showType()) }); } |