diff options
Diffstat (limited to 'src/libexpr/primops.cc')
-rw-r--r-- | src/libexpr/primops.cc | 228 |
1 files changed, 127 insertions, 101 deletions
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc index 9cff4b365..2b340fe52 100644 --- a/src/libexpr/primops.cc +++ b/src/libexpr/primops.cc @@ -350,26 +350,22 @@ void prim_exec(EvalState & state, const PosIdx pos, Value * * args, Value & v) auto elems = args[0]->listElems(); auto count = args[0]->listSize(); if (count == 0) - state.debugThrowLastTrace(EvalError({ - .msg = hintfmt("at least one argument to 'exec' required"), - .errPos = state.positions[pos] - })); + state.error("at least one argument to 'exec' required").atPos(pos).debugThrow<EvalError>(); PathSet context; - auto program = state.coerceToString(pos, *elems[0], context, false, false, - "while evaluating the first element of the argument passed to builtins.exec").toOwned(); + auto program = state.coerceToString(pos, *elems[0], context, + "while evaluating the first element of the argument passed to builtins.exec", + false, false).toOwned(); Strings commandArgs; for (unsigned int i = 1; i < args[0]->listSize(); ++i) { - commandArgs.push_back(state.coerceToString(pos, *elems[i], context, false, false, - "while evaluating an element of the argument passed to builtins.exec").toOwned()); + commandArgs.push_back( + state.coerceToString(pos, *elems[i], context, + "while evaluating an element of the argument passed to builtins.exec", + false, false).toOwned()); } try { auto _ = state.realiseContext(context); // FIXME: Handle CA derivations } catch (InvalidPathError & e) { - state.debugThrowLastTrace(EvalError({ - .msg = hintfmt("cannot execute '%1%', since path '%2%' is not valid", - program, e.path), - .errPos = state.positions[pos] - })); + state.error("cannot execute '%1%', since path '%2%' is not valid", program, e.path).atPos(pos).debugThrow<EvalError>(); } auto output = runProgram(program, true, commandArgs); @@ -598,7 +594,8 @@ struct CompareValues state.error("cannot compare %s with %s; values of that type are incomparable", showType(*v1), showType(*v2)).debugThrow<EvalError>(); } } catch (Error & e) { - e.addTrace(nullptr, errorCtx); + if (!errorCtx.empty()) + e.addTrace(nullptr, errorCtx); throw; } } @@ -620,15 +617,7 @@ static Bindings::iterator getAttr( { Bindings::iterator value = attrSet->find(attrSym); if (value == attrSet->end()) { - throw TypeError({ - .msg = hintfmt("attribute '%s' missing %s", state.symbols[attrSym], normaltxt(errorCtx)), - .errPos = state.positions[attrSet->pos], - }); - // TODO XXX - // Adding another trace for the function name to make it clear - // which call received wrong arguments. - //e.addTrace(state.positions[pos], hintfmt("while invoking '%s'", funcName)); - //state.debugThrowLastTrace(e); + state.error("attribute '%s' missing", state.symbols[attrSym]).withTrace(noPos, errorCtx).debugThrow<TypeError>(); } return value; } @@ -801,8 +790,10 @@ static void prim_addErrorContext(EvalState & state, const PosIdx pos, Value * * v = *args[1]; } catch (Error & e) { PathSet context; - e.addTrace(nullptr, state.coerceToString(pos, *args[0], context, - "while evaluating the error message passed to builtins.addErrorContext").toOwned()); + auto message = state.coerceToString(pos, *args[0], context, + "while evaluating the error message passed to builtins.addErrorContext", + false, false).toOwned(); + e.addTrace(nullptr, message); throw; } } @@ -1006,6 +997,7 @@ static void prim_second(EvalState & state, const PosIdx pos, Value * * args, Val * Derivations *************************************************************/ +static void derivationStrictInternal(EvalState & state, const std::string & name, Bindings * attrs, Value & v); /* Construct (as a unobservable side effect) a Nix derivation expression that performs the derivation described by the argument @@ -1016,32 +1008,68 @@ static void prim_second(EvalState & state, const PosIdx pos, Value * * args, Val derivation. */ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - using nlohmann::json; state.forceAttrs(*args[0], pos, "while evaluating the argument passed to builtins.derivationStrict"); + Bindings * attrs = args[0]->attrs; + /* Figure out the name first (for stack backtraces). */ - Bindings::iterator attr = getAttr(state, state.sName, args[0]->attrs, "in the attrset passed as argument to builtins.derivationStrict"); + Bindings::iterator nameAttr = getAttr(state, state.sName, attrs, "in the attrset passed as argument to builtins.derivationStrict"); std::string drvName; - const auto posDrvName = attr->pos; try { - drvName = state.forceStringNoCtx(*attr->value, pos, "while evaluating the `name` attribute passed to builtins.derivationStrict"); + drvName = state.forceStringNoCtx(*nameAttr->value, pos, "while evaluating the `name` attribute passed to builtins.derivationStrict"); + } catch (Error & e) { + e.addTrace(state.positions[nameAttr->pos], "while evaluating the derivation attribute 'name'"); + throw; + } + + try { + derivationStrictInternal(state, drvName, attrs, v); } catch (Error & e) { - e.addTrace(state.positions[posDrvName], "while evaluating the derivation attribute 'name'"); + Pos pos = state.positions[nameAttr->pos]; + /* + * Here we make two abuses of the error system + * + * 1. We print the location as a string to avoid a code snippet being + * printed. While the location of the name attribute is a good hint, the + * exact code there is irrelevant. + * + * 2. We mark this trace as a frame trace, meaning that we stop printing + * less important traces from now on. In particular, this prevents the + * display of the automatic "while calling builtins.derivationStrict" + * trace, which is of little use for the public we target here. + * + * Please keep in mind that error reporting is done on a best-effort + * basis in nix. There is no accurate location for a derivation, as it + * often results from the composition of several functions + * (derivationStrict, derivation, mkDerivation, mkPythonModule, etc.) + */ + e.addTrace(nullptr, hintfmt( + "while evaluating derivation '%s'\n" + " whose name attribute is located at %s", + drvName, pos), true); throw; } +} +static void derivationStrictInternal(EvalState & state, const std::string & +drvName, Bindings * attrs, Value & v) +{ /* Check whether attributes should be passed as a JSON file. */ + using nlohmann::json; std::optional<json> jsonObject; - attr = args[0]->attrs->find(state.sStructuredAttrs); - if (attr != args[0]->attrs->end() && state.forceBool(*attr->value, pos, "while evaluating the `__structuredAttrs` attribute passed to builtins.derivationStrict")) + auto attr = attrs->find(state.sStructuredAttrs); + if (attr != attrs->end() && + state.forceBool(*attr->value, noPos, + "while evaluating the `__structuredAttrs` " + "attribute passed to builtins.derivationStrict")) jsonObject = json::object(); /* Check whether null attributes should be ignored. */ bool ignoreNulls = false; - attr = args[0]->attrs->find(state.sIgnoreNulls); - if (attr != args[0]->attrs->end()) - ignoreNulls = state.forceBool(*attr->value, pos, "while evaluating the `__ignoreNulls` attribute passed to builtins.derivationStrict"); + attr = attrs->find(state.sIgnoreNulls); + if (attr != attrs->end()) + ignoreNulls = state.forceBool(*attr->value, noPos, "while evaluating the `__ignoreNulls` attribute " "passed to builtins.derivationStrict"); /* Build the derivation expression by processing the attributes. */ Derivation drv; @@ -1058,7 +1086,7 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * StringSet outputs; outputs.insert("out"); - for (auto & i : args[0]->attrs->lexicographicOrder(state.symbols)) { + for (auto & i : attrs->lexicographicOrder(state.symbols)) { if (i->name == state.sIgnoreNulls) continue; const std::string & key = state.symbols[i->name]; vomit("processing attribute '%1%'", key); @@ -1069,7 +1097,7 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * else state.debugThrowLastTrace(EvalError({ .msg = hintfmt("invalid value '%s' for 'outputHashMode' attribute", s), - .errPos = state.positions[posDrvName] + .errPos = state.positions[noPos] })); }; @@ -1079,7 +1107,7 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * if (outputs.find(j) != outputs.end()) state.debugThrowLastTrace(EvalError({ .msg = hintfmt("duplicate derivation output '%1%'", j), - .errPos = state.positions[posDrvName] + .errPos = state.positions[noPos] })); /* !!! Check whether j is a valid attribute name. */ @@ -1089,34 +1117,35 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * if (j == "drv") state.debugThrowLastTrace(EvalError({ .msg = hintfmt("invalid derivation output name 'drv'" ), - .errPos = state.positions[posDrvName] + .errPos = state.positions[noPos] })); outputs.insert(j); } if (outputs.empty()) state.debugThrowLastTrace(EvalError({ .msg = hintfmt("derivation cannot have an empty set of outputs"), - .errPos = state.positions[posDrvName] + .errPos = state.positions[noPos] })); }; try { + // This try-catch block adds context for most errors. + // Use this empty error context to signify that we defer to it. + const std::string_view context_below(""); if (ignoreNulls) { - state.forceValue(*i->value, pos); + state.forceValue(*i->value, noPos); if (i->value->type() == nNull) continue; } if (i->name == state.sContentAddressed) { - contentAddressed = state.forceBool(*i->value, pos, - "while evaluating the `__contentAddressed` attribute passed to builtins.derivationStrict"); + contentAddressed = state.forceBool(*i->value, noPos, context_below); if (contentAddressed) settings.requireExperimentalFeature(Xp::CaDerivations); } else if (i->name == state.sImpure) { - isImpure = state.forceBool(*i->value, pos, - "while evaluating the 'impure' attribute passed to builtins.derivationStrict"); + isImpure = state.forceBool(*i->value, noPos, context_below); if (isImpure) settings.requireExperimentalFeature(Xp::ImpureDerivations); } @@ -1124,11 +1153,11 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * /* The `args' attribute is special: it supplies the command-line arguments to the builder. */ else if (i->name == state.sArgs) { - state.forceList(*i->value, pos, - "while evaluating the `args` attribute passed to builtins.derivationStrict"); + state.forceList(*i->value, noPos, context_below); for (auto elem : i->value->listItems()) { - auto s = state.coerceToString(posDrvName, *elem, context, true, - "while evaluating an element of the `args` argument passed to builtins.derivationStrict").toOwned(); + auto s = state.coerceToString(noPos, *elem, context, + "while evaluating an element of the argument list", + true).toOwned(); drv.args.push_back(s); } } @@ -1141,29 +1170,29 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * if (i->name == state.sStructuredAttrs) continue; - (*jsonObject)[key] = printValueAsJSON(state, true, *i->value, pos, context); + (*jsonObject)[key] = printValueAsJSON(state, true, *i->value, noPos, context); if (i->name == state.sBuilder) - drv.builder = state.forceString(*i->value, context, posDrvName, "while evaluating the `builder` attribute passed to builtins.derivationStrict"); + drv.builder = state.forceString(*i->value, context, noPos, context_below); else if (i->name == state.sSystem) - drv.platform = state.forceStringNoCtx(*i->value, posDrvName, "while evaluating the `system` attribute passed to builtins.derivationStrict"); + drv.platform = state.forceStringNoCtx(*i->value, noPos, context_below); else if (i->name == state.sOutputHash) - outputHash = state.forceStringNoCtx(*i->value, posDrvName, "while evaluating the `outputHash` attribute passed to builtins.derivationStrict"); + outputHash = state.forceStringNoCtx(*i->value, noPos, context_below); else if (i->name == state.sOutputHashAlgo) - outputHashAlgo = state.forceStringNoCtx(*i->value, posDrvName, "while evaluating the `outputHashAlgo` attribute passed to builtins.derivationStrict"); + outputHashAlgo = state.forceStringNoCtx(*i->value, noPos, context_below); else if (i->name == state.sOutputHashMode) - handleHashMode(state.forceStringNoCtx(*i->value, posDrvName, "while evaluating the `outputHashMode` attribute passed to builtins.derivationStrict")); + handleHashMode(state.forceStringNoCtx(*i->value, noPos, context_below)); else if (i->name == state.sOutputs) { /* Require ‘outputs’ to be a list of strings. */ - state.forceList(*i->value, posDrvName, "while evaluating the `outputs` attribute passed to builtins.derivationStrict"); + state.forceList(*i->value, noPos, context_below); Strings ss; for (auto elem : i->value->listItems()) - ss.emplace_back(state.forceStringNoCtx(*elem, posDrvName, "while evaluating an element of the `outputs` attribute passed to builtins.derivationStrict")); + ss.emplace_back(state.forceStringNoCtx(*elem, noPos, context_below)); handleOutputs(ss); } } else { - auto s = state.coerceToString(i->pos, *i->value, context, true, "while evaluating an attribute passed to builtins.derivationStrict").toOwned(); + auto s = state.coerceToString(noPos, *i->value, context, context_below, true).toOwned(); drv.env.emplace(key, s); if (i->name == state.sBuilder) drv.builder = std::move(s); else if (i->name == state.sSystem) drv.platform = std::move(s); @@ -1177,8 +1206,8 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * } } catch (Error & e) { - e.addTrace(nullptr, - hintfmt("while evaluating the attribute '%1%' of the derivation '%2%'", key, drvName), + e.addTrace(state.positions[i->pos], + hintfmt("while evaluating attribute '%1%' of derivation '%2%'", key, drvName), true); throw; } @@ -1223,20 +1252,20 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * if (drv.builder == "") state.debugThrowLastTrace(EvalError({ .msg = hintfmt("required attribute 'builder' missing"), - .errPos = state.positions[posDrvName] + .errPos = state.positions[noPos] })); if (drv.platform == "") state.debugThrowLastTrace(EvalError({ .msg = hintfmt("required attribute 'system' missing"), - .errPos = state.positions[posDrvName] + .errPos = state.positions[noPos] })); /* Check whether the derivation name is valid. */ if (isDerivation(drvName)) state.debugThrowLastTrace(EvalError({ .msg = hintfmt("derivation names are not allowed to end in '%s'", drvExtension), - .errPos = state.positions[posDrvName] + .errPos = state.positions[noPos] })); if (outputHash) { @@ -1247,7 +1276,7 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * if (outputs.size() != 1 || *(outputs.begin()) != "out") state.debugThrowLastTrace(Error({ .msg = hintfmt("multiple outputs are not supported in fixed-output derivations"), - .errPos = state.positions[posDrvName] + .errPos = state.positions[noPos] })); auto h = newHashAllowEmpty(*outputHash, parseHashTypeOpt(outputHashAlgo)); @@ -1268,7 +1297,7 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * if (contentAddressed && isImpure) throw EvalError({ .msg = hintfmt("derivation cannot be both content-addressed and impure"), - .errPos = state.positions[posDrvName] + .errPos = state.positions[noPos] }); auto ht = parseHashTypeOpt(outputHashAlgo).value_or(htSHA256); @@ -1312,7 +1341,7 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * if (!h) throw AssertionError({ .msg = hintfmt("derivation produced no hash for output '%s'", i), - .errPos = state.positions[posDrvName], + .errPos = state.positions[noPos], }); auto outPath = state.store->makeOutputPath(i, *h, drvName); drv.env[i] = state.store->printStorePath(outPath); @@ -1345,11 +1374,12 @@ static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * drvHashes.lock()->insert_or_assign(drvPath, h); } - auto attrs = state.buildBindings(1 + drv.outputs.size()); - attrs.alloc(state.sDrvPath).mkString(drvPathS, {"=" + drvPathS}); + auto result = state.buildBindings(1 + drv.outputs.size()); + result.alloc(state.sDrvPath).mkString(drvPathS, {"=" + drvPathS}); for (auto & i : drv.outputs) - mkOutputString(state, attrs, drvPath, drv, i); - v.mkAttrs(attrs); + mkOutputString(state, result, drvPath, drv, i); + + v.mkAttrs(result); } static RegisterPrimOp primop_derivationStrict(RegisterPrimOp::Info { @@ -1492,7 +1522,9 @@ static RegisterPrimOp primop_pathExists({ static void prim_baseNameOf(EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - v.mkString(baseNameOf(*state.coerceToString(pos, *args[0], context, false, false, "while evaluating the first argument passed to builtins.baseNameOf")), context); + v.mkString(baseNameOf(*state.coerceToString(pos, *args[0], context, + "while evaluating the first argument passed to builtins.baseNameOf", + false, false)), context); } static RegisterPrimOp primop_baseNameOf({ @@ -1512,7 +1544,9 @@ static RegisterPrimOp primop_baseNameOf({ static void prim_dirOf(EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - auto path = state.coerceToString(pos, *args[0], context, false, false, "while evaluating the first argument passed to builtins.dirOf"); + auto path = state.coerceToString(pos, *args[0], context, + "while evaluating the first argument passed to builtins.dirOf", + false, false); auto dir = dirOf(*path); if (args[0]->type() == nPath) v.mkPath(dir); else v.mkString(dir, context); } @@ -1578,8 +1612,9 @@ static void prim_findFile(EvalState & state, const PosIdx pos, Value * * args, V i = getAttr(state, state.sPath, v2->attrs, "in an element of the __nixPath"); PathSet context; - auto path = state.coerceToString(pos, *i->value, context, false, false, - "while evaluating the `path` attribute of an element of the list passed to builtins.findFile").toOwned(); + auto path = state.coerceToString(pos, *i->value, context, + "while evaluating the `path` attribute of an element of the list passed to builtins.findFile", + false, false).toOwned(); try { auto rewrites = state.realiseContext(context); @@ -2622,14 +2657,9 @@ static void prim_zipAttrsWith(EvalState & state, const PosIdx pos, Value * * arg for (unsigned int n = 0; n < listSize; ++n) { Value * vElem = listElems[n]; - try { - state.forceAttrs(*vElem, noPos, "while evaluating a value of the list passed as second argument to builtins.zipAttrsWith"); - for (auto & attr : *vElem->attrs) - attrsSeen[attr.name].first++; - } catch (TypeError & e) { - e.addTrace(state.positions[pos], hintfmt("while invoking '%s'", "zipAttrsWith")); - state.debugThrowLastTrace(e); - } + state.forceAttrs(*vElem, noPos, "while evaluating a value of the list passed as second argument to builtins.zipAttrsWith"); + for (auto & attr : *vElem->attrs) + attrsSeen[attr.name].first++; } auto attrs = state.buildBindings(attrsSeen.size()); @@ -3013,13 +3043,13 @@ static void prim_genList(EvalState & state, const PosIdx pos, Value * * args, Va auto len = state.forceInt(*args[1], pos, "while evaluating the second argument passed to builtins.genList"); if (len < 0) - state.debugThrowLastTrace(EvalError({ - .msg = hintfmt("cannot create list of size %1%", len), - .errPos = state.positions[pos] - })); + state.error("cannot create list of size %1%", len).debugThrow<EvalError>(); - state.mkList(v, len); + // More strict than striclty (!) necessary, but acceptable + // as evaluating map without accessing any values makes little sense. + state.forceFunction(*args[0], noPos, "while evaluating the first argument passed to builtins.genList"); + state.mkList(v, len); for (unsigned int n = 0; n < (unsigned int) len; ++n) { auto arg = state.allocValue(); arg->mkInt(n); @@ -3067,6 +3097,8 @@ static void prim_sort(EvalState & state, const PosIdx pos, Value * * args, Value auto comparator = [&](Value * a, Value * b) { /* Optimization: if the comparator is lessThan, bypass callFunction. */ + /* TODO: (layus) this is absurd. An optimisation like this + should be outside the lambda creation */ if (args[0]->isPrimOp() && args[0]->primOp->fun == prim_lessThan) return CompareValues(state, noPos, "while evaluating the ordering function passed to builtins.sort")(a, b); @@ -3227,12 +3259,7 @@ static void prim_concatMap(EvalState & state, const PosIdx pos, Value * * args, for (unsigned int n = 0; n < nrLists; ++n) { Value * vElem = args[1]->listElems()[n]; state.callFunction(*args[0], *vElem, lists[n], pos); - try { - state.forceList(lists[n], lists[n].determinePos(args[0]->determinePos(pos)), "while evaluating the return value of the function passed to buitlins.concatMap"); - } catch (TypeError &e) { - e.addTrace(state.positions[pos], hintfmt("while invoking '%s'", "concatMap")); - state.debugThrowLastTrace(e); - } + state.forceList(lists[n], lists[n].determinePos(args[0]->determinePos(pos)), "while evaluating the return value of the function passed to buitlins.concatMap"); len += lists[n].listSize(); } @@ -3412,7 +3439,7 @@ static void prim_lessThan(EvalState & state, const PosIdx pos, Value * * args, V state.forceValue(*args[0], pos); state.forceValue(*args[1], pos); // pos is exact here, no need for a message. - CompareValues comp(state, pos, ""); + CompareValues comp(state, noPos, ""); v.mkBool(comp(args[0], args[1])); } @@ -3439,7 +3466,9 @@ static RegisterPrimOp primop_lessThan({ static void prim_toString(EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - auto s = state.coerceToString(pos, *args[0], context, true, false, "while evaluating the first argument passed to builtins.toString"); + auto s = state.coerceToString(pos, *args[0], context, + "while evaluating the first argument passed to builtins.toString", + true, false); v.mkString(*s, context); } @@ -3791,21 +3820,18 @@ static void prim_replaceStrings(EvalState & state, const PosIdx pos, Value * * a state.forceList(*args[0], pos, "while evaluating the first argument passed to builtins.replaceStrings"); state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.replaceStrings"); if (args[0]->listSize() != args[1]->listSize()) - state.debugThrowLastTrace(EvalError({ - .msg = hintfmt("'from' and 'to' arguments to 'replaceStrings' have different lengths"), - .errPos = state.positions[pos] - })); + state.error("'from' and 'to' arguments passed to builtins.replaceStrings have different lengths").atPos(pos).debugThrow<EvalError>(); std::vector<std::string> from; from.reserve(args[0]->listSize()); for (auto elem : args[0]->listItems()) - from.emplace_back(state.forceString(*elem, pos, "while evaluating one of the strings to replace in builtins.replaceStrings")); + from.emplace_back(state.forceString(*elem, pos, "while evaluating one of the strings to replace passed to builtins.replaceStrings")); std::vector<std::pair<std::string, PathSet>> to; to.reserve(args[1]->listSize()); for (auto elem : args[1]->listItems()) { PathSet ctx; - auto s = state.forceString(*elem, ctx, pos, "while evaluating one of the replacement strings of builtins.replaceStrings"); + auto s = state.forceString(*elem, ctx, pos, "while evaluating one of the replacement strings passed to builtins.replaceStrings"); to.emplace_back(s, std::move(ctx)); } |