diff options
Diffstat (limited to 'src/libexpr/primops.cc')
| -rw-r--r-- | src/libexpr/primops.cc | 1265 |
1 files changed, 697 insertions, 568 deletions
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc index 2ccc63328..7e4b944b1 100644 --- a/src/libexpr/primops.cc +++ b/src/libexpr/primops.cc @@ -5,14 +5,15 @@ #include "globals.hh" #include "json-to-value.hh" #include "names.hh" +#include "references.hh" #include "store-api.hh" #include "util.hh" -#include "json.hh" #include "value-to-json.hh" #include "value-to-xml.hh" #include "primops.hh" #include <boost/container/small_vector.hpp> +#include <nlohmann/json.hpp> #include <sys/types.h> #include <sys/stat.h> @@ -46,7 +47,7 @@ StringMap EvalState::realiseContext(const PathSet & context) auto [ctx, outputName] = decodeContext(*store, i); auto ctxS = store->printStorePath(ctx); if (!store->isValidPath(ctx)) - throw InvalidPathError(store->printStorePath(ctx)); + debugThrowLastTrace(InvalidPathError(store->printStorePath(ctx))); if (!outputName.empty() && ctx.isDerivation()) { drvs.push_back({ctx, {outputName}}); } else { @@ -57,9 +58,9 @@ StringMap EvalState::realiseContext(const PathSet & context) if (drvs.empty()) return {}; if (!evalSettings.enableImportFromDerivation) - throw Error( + debugThrowLastTrace(Error( "cannot build '%1%' during evaluation because the option 'allow-import-from-derivation' is disabled", - store->printStorePath(drvs.begin()->drvPath)); + store->printStorePath(drvs.begin()->drvPath))); /* Build/substitute the context. */ std::vector<DerivedPath> buildReqs; @@ -68,14 +69,15 @@ StringMap EvalState::realiseContext(const PathSet & context) /* Get all the output paths corresponding to the placeholders we had */ for (auto & [drvPath, outputs] : drvs) { - auto outputPaths = store->queryDerivationOutputMap(drvPath); + const auto outputPaths = store->queryDerivationOutputMap(drvPath); for (auto & outputName : outputs) { - if (outputPaths.count(outputName) == 0) - throw Error("derivation '%s' does not have an output named '%s'", - store->printStorePath(drvPath), outputName); + auto outputPath = get(outputPaths, outputName); + if (!outputPath) + debugThrowLastTrace(Error("derivation '%s' does not have an output named '%s'", + store->printStorePath(drvPath), outputName)); res.insert_or_assign( downstreamPlaceholder(*store, drvPath, outputName), - store->printStorePath(outputPaths.at(outputName)) + store->printStorePath(*outputPath) ); } } @@ -96,19 +98,11 @@ struct RealisePathFlags { bool checkForPureEval = true; }; -static Path realisePath(EvalState & state, const Pos & pos, Value & v, const RealisePathFlags flags = {}) +static Path realisePath(EvalState & state, const PosIdx pos, Value & v, const RealisePathFlags flags = {}) { PathSet context; - auto path = [&]() - { - try { - return state.coerceToPath(pos, v, context); - } catch (Error & e) { - e.addTrace(pos, "while realising the context of a path"); - throw; - } - }(); + auto path = state.coerceToPath(noPos, v, context, "while realising the context of a path"); try { StringMap rewrites = state.realiseContext(context); @@ -119,7 +113,7 @@ static Path realisePath(EvalState & state, const Pos & pos, Value & v, const Rea ? state.checkSourcePath(realPath) : realPath; } catch (Error & e) { - e.addTrace(pos, "while realising the context of path '%s'", path); + e.addTrace(state.positions[pos], "while realising the context of path '%s'", path); throw; } } @@ -157,7 +151,7 @@ static void mkOutputString( /* Load and evaluate an expression from path specified by the argument. */ -static void import(EvalState & state, const Pos & pos, Value & vPath, Value * vScope, Value & v) +static void import(EvalState & state, const PosIdx pos, Value & vPath, Value * vScope, Value & v) { auto path = realisePath(state, pos, vPath); @@ -195,9 +189,9 @@ static void import(EvalState & state, const Pos & pos, Value & vPath, Value * vS , "/"), **state.vImportedDrvToDerivation); } - state.forceFunction(**state.vImportedDrvToDerivation, pos); + state.forceFunction(**state.vImportedDrvToDerivation, pos, "while evaluating imported-drv-to-derivation.nix.gen.hh"); v.mkApp(*state.vImportedDrvToDerivation, w); - state.forceAttrs(v, pos); + state.forceAttrs(v, pos, "while calling imported-drv-to-derivation.nix.gen.hh"); } else if (path == corepkgsPrefix + "fetchurl.nix") { @@ -210,16 +204,16 @@ static void import(EvalState & state, const Pos & pos, Value & vPath, Value * vS if (!vScope) state.evalFile(path, v); else { - state.forceAttrs(*vScope, pos); + state.forceAttrs(*vScope, pos, "while evaluating the first argument passed to builtins.scopedImport"); Env * env = &state.allocEnv(vScope->attrs->size()); env->up = &state.baseEnv; - StaticEnv staticEnv(false, &state.staticBaseEnv, vScope->attrs->size()); + auto staticEnv = std::make_shared<StaticEnv>(false, state.staticBaseEnv.get(), vScope->attrs->size()); unsigned int displ = 0; for (auto & attr : *vScope->attrs) { - staticEnv.vars.emplace_back(attr.name, displ); + staticEnv->vars.emplace_back(attr.name, displ); env->values[displ++] = attr.value; } @@ -237,7 +231,7 @@ static void import(EvalState & state, const Pos & pos, Value & vPath, Value * vS static RegisterPrimOp primop_scopedImport(RegisterPrimOp::Info { .name = "scopedImport", .arity = 2, - .fun = [](EvalState & state, const Pos & pos, Value * * args, Value & v) + .fun = [](EvalState & state, const PosIdx pos, Value * * args, Value & v) { import(state, pos, *args[1], args[0], v); } @@ -299,7 +293,7 @@ static RegisterPrimOp primop_import({ (The function argument doesn’t have to be called `x` in `foo.nix`; any name would work.) )", - .fun = [](EvalState & state, const Pos & pos, Value * * args, Value & v) + .fun = [](EvalState & state, const PosIdx pos, Value * * args, Value & v) { import(state, pos, *args[0], nullptr, v); } @@ -310,25 +304,24 @@ static RegisterPrimOp primop_import({ extern "C" typedef void (*ValueInitializer)(EvalState & state, Value & v); /* Load a ValueInitializer from a DSO and return whatever it initializes */ -void prim_importNative(EvalState & state, const Pos & pos, Value * * args, Value & v) +void prim_importNative(EvalState & state, const PosIdx pos, Value * * args, Value & v) { auto path = realisePath(state, pos, *args[0]); - std::string sym(state.forceStringNoCtx(*args[1], pos)); + std::string sym(state.forceStringNoCtx(*args[1], pos, "while evaluating the second argument passed to builtins.importNative")); void *handle = dlopen(path.c_str(), RTLD_LAZY | RTLD_LOCAL); if (!handle) - throw EvalError("could not open '%1%': %2%", path, dlerror()); + state.debugThrowLastTrace(EvalError("could not open '%1%': %2%", path, dlerror())); dlerror(); ValueInitializer func = (ValueInitializer) dlsym(handle, sym.c_str()); if(!func) { char *message = dlerror(); if (message) - throw EvalError("could not load symbol '%1%' from '%2%': %3%", sym, path, message); + state.debugThrowLastTrace(EvalError("could not load symbol '%1%' from '%2%': %3%", sym, path, message)); else - throw EvalError("symbol '%1%' from '%2%' resolved to NULL when a function pointer was expected", - sym, path); + state.debugThrowLastTrace(EvalError("symbol '%1%' from '%2%' resolved to NULL when a function pointer was expected", sym, path)); } (func)(state, v); @@ -338,52 +331,52 @@ void prim_importNative(EvalState & state, const Pos & pos, Value * * args, Value /* Execute a program and parse its output */ -void prim_exec(EvalState & state, const Pos & pos, Value * * args, Value & v) +void prim_exec(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceList(*args[0], pos); + state.forceList(*args[0], pos, "while evaluating the first argument passed to builtins.exec"); auto elems = args[0]->listElems(); auto count = args[0]->listSize(); - if (count == 0) { - throw EvalError({ + if (count == 0) + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("at least one argument to 'exec' required"), - .errPos = pos - }); - } + .errPos = state.positions[pos] + })); PathSet context; - auto program = state.coerceToString(pos, *elems[0], context, false, false).toOwned(); + auto program = state.coerceToString(pos, *elems[0], context, false, false, + "while evaluating the first element of the argument passed to builtins.exec").toOwned(); Strings commandArgs; for (unsigned int i = 1; i < args[0]->listSize(); ++i) { - commandArgs.push_back(state.coerceToString(pos, *elems[i], context, false, false).toOwned()); + commandArgs.push_back(state.coerceToString(pos, *elems[i], context, false, false, + "while evaluating an element of the argument passed to builtins.exec").toOwned()); } try { auto _ = state.realiseContext(context); // FIXME: Handle CA derivations } catch (InvalidPathError & e) { - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("cannot execute '%1%', since path '%2%' is not valid", program, e.path), - .errPos = pos - }); + .errPos = state.positions[pos] + })); } auto output = runProgram(program, true, commandArgs); Expr * parsed; try { - parsed = state.parseExprFromString(std::move(output), pos.file); + parsed = state.parseExprFromString(std::move(output), "/"); } catch (Error & e) { - e.addTrace(pos, "While parsing the output from '%1%'", program); + e.addTrace(state.positions[pos], "while parsing the output from '%1%'", program); throw; } try { state.eval(parsed, v); } catch (Error & e) { - e.addTrace(pos, "While evaluating the output from '%1%'", program); + e.addTrace(state.positions[pos], "while evaluating the output from '%1%'", program); throw; } } - /* Return a string representing the type of the expression. */ -static void prim_typeOf(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_typeOf(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); std::string t; @@ -402,7 +395,7 @@ static void prim_typeOf(EvalState & state, const Pos & pos, Value * * args, Valu case nFloat: t = "float"; break; case nThunk: abort(); } - v.mkString(state.symbols.create(t)); + v.mkString(t); } static RegisterPrimOp primop_typeOf({ @@ -417,7 +410,7 @@ static RegisterPrimOp primop_typeOf({ }); /* Determine whether the argument is the null value. */ -static void prim_isNull(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_isNull(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); v.mkBool(args[0]->type() == nNull); @@ -437,7 +430,7 @@ static RegisterPrimOp primop_isNull({ }); /* Determine whether the argument is a function. */ -static void prim_isFunction(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_isFunction(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); v.mkBool(args[0]->type() == nFunction); @@ -453,7 +446,7 @@ static RegisterPrimOp primop_isFunction({ }); /* Determine whether the argument is an integer. */ -static void prim_isInt(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_isInt(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); v.mkBool(args[0]->type() == nInt); @@ -469,7 +462,7 @@ static RegisterPrimOp primop_isInt({ }); /* Determine whether the argument is a float. */ -static void prim_isFloat(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_isFloat(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); v.mkBool(args[0]->type() == nFloat); @@ -485,7 +478,7 @@ static RegisterPrimOp primop_isFloat({ }); /* Determine whether the argument is a string. */ -static void prim_isString(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_isString(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); v.mkBool(args[0]->type() == nString); @@ -501,7 +494,7 @@ static RegisterPrimOp primop_isString({ }); /* Determine whether the argument is a Boolean. */ -static void prim_isBool(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_isBool(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); v.mkBool(args[0]->type() == nBool); @@ -517,7 +510,7 @@ static RegisterPrimOp primop_isBool({ }); /* Determine whether the argument is a path. */ -static void prim_isPath(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_isPath(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); v.mkBool(args[0]->type() == nPath); @@ -532,49 +525,75 @@ static RegisterPrimOp primop_isPath({ .fun = prim_isPath, }); +template<typename Callable> + static inline void withExceptionContext(Trace trace, Callable&& func) +{ + try + { + func(); + } + catch(Error & e) + { + e.pushTrace(trace); + throw; + } +} + struct CompareValues { EvalState & state; + const PosIdx pos; + const std::string_view errorCtx; - CompareValues(EvalState & state) : state(state) { }; + CompareValues(EvalState & state, const PosIdx pos, const std::string_view && errorCtx) : state(state), pos(pos), errorCtx(errorCtx) { }; bool operator () (Value * v1, Value * v2) const { - if (v1->type() == nFloat && v2->type() == nInt) - return v1->fpoint < v2->integer; - if (v1->type() == nInt && v2->type() == nFloat) - return v1->integer < v2->fpoint; - if (v1->type() != v2->type()) - throw EvalError("cannot compare %1% with %2%", showType(*v1), showType(*v2)); - switch (v1->type()) { - case nInt: - return v1->integer < v2->integer; - case nFloat: - return v1->fpoint < v2->fpoint; - case nString: - return strcmp(v1->string.s, v2->string.s) < 0; - case nPath: - return strcmp(v1->path, v2->path) < 0; - case nList: - // Lexicographic comparison - for (size_t i = 0;; i++) { - if (i == v2->listSize()) { - return false; - } else if (i == v1->listSize()) { - return true; - } else if (!state.eqValues(*v1->listElems()[i], *v2->listElems()[i])) { - return (*this)(v1->listElems()[i], v2->listElems()[i]); + return (*this)(v1, v2, errorCtx); + } + + bool operator () (Value * v1, Value * v2, std::string_view errorCtx) const + { + try { + if (v1->type() == nFloat && v2->type() == nInt) + return v1->fpoint < v2->integer; + if (v1->type() == nInt && v2->type() == nFloat) + return v1->integer < v2->fpoint; + if (v1->type() != v2->type()) + state.error("cannot compare %s with %s", showType(*v1), showType(*v2)).debugThrow<EvalError>(); + switch (v1->type()) { + case nInt: + return v1->integer < v2->integer; + case nFloat: + return v1->fpoint < v2->fpoint; + case nString: + return strcmp(v1->string.s, v2->string.s) < 0; + case nPath: + return strcmp(v1->path, v2->path) < 0; + case nList: + // Lexicographic comparison + for (size_t i = 0;; i++) { + if (i == v2->listSize()) { + return false; + } else if (i == v1->listSize()) { + return true; + } else if (!state.eqValues(*v1->listElems()[i], *v2->listElems()[i], pos, errorCtx)) { + return (*this)(v1->listElems()[i], v2->listElems()[i], "while comparing two list elements"); + } } - } - default: - throw EvalError("cannot compare %1% with %2%", showType(*v1), showType(*v2)); + default: + 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); + throw; } } }; #if HAVE_BOEHMGC -typedef std::list<Value *, gc_allocator<Value *> > ValueList; +typedef std::list<Value *, gc_allocator<Value *>> ValueList; #else typedef std::list<Value *> ValueList; #endif @@ -582,105 +601,75 @@ typedef std::list<Value *> ValueList; static Bindings::iterator getAttr( EvalState & state, - std::string_view funcName, Symbol attrSym, Bindings * attrSet, - const Pos & pos) + std::string_view errorCtx) { Bindings::iterator value = attrSet->find(attrSym); if (value == attrSet->end()) { - hintformat errorMsg = hintfmt( - "attribute '%s' missing for call to '%s'", - attrSym, - funcName - ); - - Pos aPos = *attrSet->pos; - if (aPos == noPos) { - throw TypeError({ - .msg = errorMsg, - .errPos = pos, - }); - } else { - auto e = TypeError({ - .msg = errorMsg, - .errPos = aPos, - }); - - // Adding another trace for the function name to make it clear - // which call received wrong arguments. - e.addTrace(pos, hintfmt("while invoking '%s'", funcName)); - throw e; - } + 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); } - return value; } -static void prim_genericClosure(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_genericClosure(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceAttrs(*args[0], pos); + state.forceAttrs(*args[0], noPos, "while evaluating the first argument passed to builtins.genericClosure"); /* Get the start set. */ - Bindings::iterator startSet = getAttr( - state, - "genericClosure", - state.sStartSet, - args[0]->attrs, - pos - ); + Bindings::iterator startSet = getAttr(state, state.sStartSet, args[0]->attrs, "in the attrset passed as argument to builtins.genericClosure"); - state.forceList(*startSet->value, pos); + state.forceList(*startSet->value, noPos, "while evaluating the 'startSet' attribute passed as argument to builtins.genericClosure"); ValueList workSet; for (auto elem : startSet->value->listItems()) workSet.push_back(elem); - /* Get the operator. */ - Bindings::iterator op = getAttr( - state, - "genericClosure", - state.sOperator, - args[0]->attrs, - pos - ); + if (startSet->value->listSize() == 0) { + v = *startSet->value; + return; + } - state.forceValue(*op->value, pos); + /* Get the operator. */ + Bindings::iterator op = getAttr(state, state.sOperator, args[0]->attrs, "in the attrset passed as argument to builtins.genericClosure"); + state.forceFunction(*op->value, noPos, "while evaluating the 'operator' attribute passed as argument to builtins.genericClosure"); - /* Construct the closure by applying the operator to element of + /* Construct the closure by applying the operator to elements of `workSet', adding the result to `workSet', continuing until no new elements are found. */ ValueList res; // `doneKeys' doesn't need to be a GC root, because its values are // reachable from res. - auto cmp = CompareValues(state); + auto cmp = CompareValues(state, noPos, "while comparing the `key` attributes of two genericClosure elements"); std::set<Value *, decltype(cmp)> doneKeys(cmp); while (!workSet.empty()) { Value * e = *(workSet.begin()); workSet.pop_front(); - state.forceAttrs(*e, pos); + state.forceAttrs(*e, noPos, "while evaluating one of the elements generated by (or initially passed to) builtins.genericClosure"); - Bindings::iterator key = - e->attrs->find(state.sKey); - if (key == e->attrs->end()) - throw EvalError({ - .msg = hintfmt("attribute 'key' required"), - .errPos = pos - }); - state.forceValue(*key->value, pos); + Bindings::iterator key = getAttr(state, state.sKey, e->attrs, "in one of the attrsets generated by (or initially passed to) builtins.genericClosure"); + state.forceValue(*key->value, noPos); if (!doneKeys.insert(key->value).second) continue; res.push_back(e); /* Call the `operator' function with `e' as argument. */ - Value call; - call.mkApp(op->value, e); - state.forceList(call, pos); + Value newElements; + state.callFunction(*op->value, 1, &e, newElements, noPos); + state.forceList(newElements, noPos, "while evaluating the return value of the `operator` passed to builtins.genericClosure"); /* Add the values returned by the operator to the work set. */ - for (auto elem : call.listItems()) { - state.forceValue(*elem, pos); + for (auto elem : newElements.listItems()) { + state.forceValue(*elem, noPos); // "while evaluating one one of the elements returned by the `operator` passed to builtins.genericClosure"); workSet.push_back(elem); } } @@ -723,17 +712,53 @@ static RegisterPrimOp primop_genericClosure(RegisterPrimOp::Info { .fun = prim_genericClosure, }); + +static RegisterPrimOp primop_break({ + .name = "break", + .args = {"v"}, + .doc = R"( + In debug mode (enabled using `--debugger`), pause Nix expression evaluation and enter the REPL. + Otherwise, return the argument `v`. + )", + .fun = [](EvalState & state, const PosIdx pos, Value * * args, Value & v) + { + if (state.debugRepl && !state.debugTraces.empty()) { + auto error = Error(ErrorInfo { + .level = lvlInfo, + .msg = hintfmt("breakpoint reached"), + .errPos = state.positions[pos], + }); + + auto & dt = state.debugTraces.front(); + state.runDebugRepl(&error, dt.env, dt.expr); + + if (state.debugQuit) { + // If the user elects to quit the repl, throw an exception. + throw Error(ErrorInfo{ + .level = lvlInfo, + .msg = hintfmt("quit the debugger"), + .errPos = nullptr, + }); + } + } + + // Return the value we were passed. + v = *args[0]; + } +}); + static RegisterPrimOp primop_abort({ .name = "abort", .args = {"s"}, .doc = R"( Abort Nix expression evaluation and print the error message *s*. )", - .fun = [](EvalState & state, const Pos & pos, Value * * args, Value & v) + .fun = [](EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - auto s = state.coerceToString(pos, *args[0], context).toOwned(); - throw Abort("evaluation aborted with the following error message: '%1%'", s); + auto s = state.coerceToString(pos, *args[0], context, + "while evaluating the error message passed to builtins.abort").toOwned(); + state.debugThrowLastTrace(Abort("evaluation aborted with the following error message: '%1%'", s)); } }); @@ -747,22 +772,24 @@ static RegisterPrimOp primop_throw({ derivations, a derivation that throws an error is silently skipped (which is not the case for `abort`). )", - .fun = [](EvalState & state, const Pos & pos, Value * * args, Value & v) + .fun = [](EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - auto s = state.coerceToString(pos, *args[0], context).toOwned(); - throw ThrownError(s); + auto s = state.coerceToString(pos, *args[0], context, + "while evaluating the error message passed to builtin.throw").toOwned(); + state.debugThrowLastTrace(ThrownError(s)); } }); -static void prim_addErrorContext(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_addErrorContext(EvalState & state, const PosIdx pos, Value * * args, Value & v) { try { state.forceValue(*args[1], pos); v = *args[1]; } catch (Error & e) { PathSet context; - e.addTrace(std::nullopt, state.coerceToString(pos, *args[0], context).toOwned()); + e.addTrace(nullptr, state.coerceToString(pos, *args[0], context, + "while evaluating the error message passed to builtins.addErrorContext").toOwned()); throw; } } @@ -773,9 +800,10 @@ static RegisterPrimOp primop_addErrorContext(RegisterPrimOp::Info { .fun = prim_addErrorContext, }); -static void prim_ceil(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_ceil(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto value = state.forceFloat(*args[0], args[0]->determinePos(pos)); + auto value = state.forceFloat(*args[0], args[0]->determinePos(pos), + "while evaluating the first argument passed to builtins.ceil"); v.mkInt(ceil(value)); } @@ -792,9 +820,9 @@ static RegisterPrimOp primop_ceil({ .fun = prim_ceil, }); -static void prim_floor(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_floor(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto value = state.forceFloat(*args[0], args[0]->determinePos(pos)); + auto value = state.forceFloat(*args[0], args[0]->determinePos(pos), "while evaluating the first argument passed to builtins.floor"); v.mkInt(floor(value)); } @@ -813,9 +841,21 @@ static RegisterPrimOp primop_floor({ /* Try evaluating the argument. Success => {success=true; value=something;}, * else => {success=false; value=false;} */ -static void prim_tryEval(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_tryEval(EvalState & state, const PosIdx pos, Value * * args, Value & v) { auto attrs = state.buildBindings(2); + + /* increment state.trylevel, and decrement it when this function returns. */ + MaintainCount trylevel(state.trylevel); + + void (* savedDebugRepl)(ref<EvalState> es, const ValMap & extraEnv) = nullptr; + if (state.debugRepl && evalSettings.ignoreExceptionsDuringTry) + { + /* to prevent starting the repl from exceptions withing a tryEval, null it. */ + savedDebugRepl = state.debugRepl; + state.debugRepl = nullptr; + } + try { state.forceValue(*args[0], pos); attrs.insert(state.sValue, args[0]); @@ -824,6 +864,11 @@ static void prim_tryEval(EvalState & state, const Pos & pos, Value * * args, Val attrs.alloc(state.sValue).mkBool(false); attrs.alloc("success").mkBool(false); } + + // restore the debugRepl pointer if we saved it earlier. + if (savedDebugRepl) + state.debugRepl = savedDebugRepl; + v.mkAttrs(attrs); } @@ -849,9 +894,9 @@ static RegisterPrimOp primop_tryEval({ }); /* Return an environment variable. Use with care. */ -static void prim_getEnv(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_getEnv(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - std::string name(state.forceStringNoCtx(*args[0], pos)); + std::string name(state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.getEnv")); v.mkString(evalSettings.restrictEval || evalSettings.pureEval ? "" : getEnv(name).value_or("")); } @@ -873,7 +918,7 @@ static RegisterPrimOp primop_getEnv({ }); /* Evaluate the first argument, then return the second argument. */ -static void prim_seq(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_seq(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); state.forceValue(*args[1], pos); @@ -892,7 +937,7 @@ static RegisterPrimOp primop_seq({ /* Evaluate the first argument deeply (i.e. recursing into lists and attrsets), then return the second argument. */ -static void prim_deepSeq(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_deepSeq(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValueDeep(*args[0]); state.forceValue(*args[1], pos); @@ -912,13 +957,13 @@ static RegisterPrimOp primop_deepSeq({ /* Evaluate the first expression and print it on standard error. Then return the second expression. Useful for debugging. */ -static void prim_trace(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_trace(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); if (args[0]->type() == nString) printError("trace: %1%", args[0]->string.s); else - printError("trace: %1%", *args[0]); + printError("trace: %1%", printValue(state, *args[0])); state.forceValue(*args[1], pos); v = *args[1]; } @@ -935,6 +980,15 @@ static RegisterPrimOp primop_trace({ }); +/* Takes two arguments and evaluates to the second one. Used as the + * builtins.traceVerbose implementation when --trace-verbose is not enabled + */ +static void prim_second(EvalState & state, const PosIdx pos, Value * * args, Value & v) +{ + state.forceValue(*args[1], pos); + v = *args[1]; +} + /************************************************************* * Derivations *************************************************************/ @@ -947,40 +1001,34 @@ static RegisterPrimOp primop_trace({ derivation; `drvPath' containing the path of the Nix expression; and `type' set to `derivation' to indicate that this is a derivation. */ -static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_derivationStrict(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceAttrs(*args[0], pos); + using nlohmann::json; + state.forceAttrs(*args[0], pos, "while evaluating the argument passed to builtins.derivationStrict"); /* Figure out the name first (for stack backtraces). */ - Bindings::iterator attr = getAttr( - state, - "derivationStrict", - state.sName, - args[0]->attrs, - pos - ); + Bindings::iterator attr = getAttr(state, state.sName, args[0]->attrs, "in the attrset passed as argument to builtins.derivationStrict"); std::string drvName; - Pos & posDrvName(*attr->pos); + const auto posDrvName = attr->pos; try { - drvName = state.forceStringNoCtx(*attr->value, pos); + drvName = state.forceStringNoCtx(*attr->value, pos, "while evaluating the `name` attribute passed to builtins.derivationStrict"); } catch (Error & e) { - e.addTrace(posDrvName, "while evaluating the derivation attribute 'name'"); + e.addTrace(state.positions[posDrvName], "while evaluating the derivation attribute 'name'"); throw; } /* Check whether attributes should be passed as a JSON file. */ - std::ostringstream jsonBuf; - std::unique_ptr<JSONObject> jsonObject; + std::optional<json> jsonObject; attr = args[0]->attrs->find(state.sStructuredAttrs); - if (attr != args[0]->attrs->end() && state.forceBool(*attr->value, pos)) - jsonObject = std::make_unique<JSONObject>(jsonBuf); + if (attr != args[0]->attrs->end() && state.forceBool(*attr->value, pos, "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); + ignoreNulls = state.forceBool(*attr->value, pos, "while evaluating the `__ignoreNulls` attribute passed to builtins.derivationStrict"); /* Build the derivation expression by processing the attributes. */ Derivation drv; @@ -997,9 +1045,9 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * StringSet outputs; outputs.insert("out"); - for (auto & i : args[0]->attrs->lexicographicOrder()) { + for (auto & i : args[0]->attrs->lexicographicOrder(state.symbols)) { if (i->name == state.sIgnoreNulls) continue; - const std::string & key = i->name; + const std::string & key = state.symbols[i->name]; vomit("processing attribute '%1%'", key); auto handleHashMode = [&](const std::string_view s) { @@ -1007,37 +1055,37 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * else if (s == "flat") ingestionMethod = FileIngestionMethod::Flat; else if (s == "text") ingestionMethod = TextHashMethod {}; else - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("invalid value '%s' for 'outputHashMode' attribute", s), - .errPos = posDrvName - }); + .errPos = state.positions[posDrvName] + })); }; auto handleOutputs = [&](const Strings & ss) { outputs.clear(); for (auto & j : ss) { if (outputs.find(j) != outputs.end()) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("duplicate derivation output '%1%'", j), - .errPos = posDrvName - }); + .errPos = state.positions[posDrvName] + })); /* !!! Check whether j is a valid attribute name. */ /* Derivations cannot be named ‘drv’, because then we'd have an attribute ‘drvPath’ in the resulting set. */ if (j == "drv") - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("invalid derivation output name 'drv'" ), - .errPos = posDrvName - }); + .errPos = state.positions[posDrvName] + })); outputs.insert(j); } if (outputs.empty()) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("derivation cannot have an empty set of outputs"), - .errPos = posDrvName - }); + .errPos = state.positions[posDrvName] + })); }; try { @@ -1048,13 +1096,15 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * } if (i->name == state.sContentAddressed) { - contentAddressed = state.forceBool(*i->value, pos); + contentAddressed = state.forceBool(*i->value, pos, + "while evaluating the `__contentAddressed` attribute passed to builtins.derivationStrict"); if (contentAddressed) settings.requireExperimentalFeature(Xp::CaDerivations); } else if (i->name == state.sImpure) { - isImpure = state.forceBool(*i->value, pos); + isImpure = state.forceBool(*i->value, pos, + "while evaluating the 'impure' attribute passed to builtins.derivationStrict"); if (isImpure) settings.requireExperimentalFeature(Xp::ImpureDerivations); } @@ -1062,9 +1112,11 @@ static void prim_derivationStrict(EvalState & state, const Pos & 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); + state.forceList(*i->value, pos, + "while evaluating the `args` attribute passed to builtins.derivationStrict"); for (auto elem : i->value->listItems()) { - auto s = state.coerceToString(posDrvName, *elem, context, true).toOwned(); + auto s = state.coerceToString(posDrvName, *elem, context, true, + "while evaluating an element of the `args` argument passed to builtins.derivationStrict").toOwned(); drv.args.push_back(s); } } @@ -1077,30 +1129,29 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * if (i->name == state.sStructuredAttrs) continue; - auto placeholder(jsonObject->placeholder(key)); - printValueAsJSON(state, true, *i->value, pos, placeholder, context); + (*jsonObject)[key] = printValueAsJSON(state, true, *i->value, pos, context); if (i->name == state.sBuilder) - drv.builder = state.forceString(*i->value, context, posDrvName); + drv.builder = state.forceString(*i->value, context, posDrvName, "while evaluating the `builder` attribute passed to builtins.derivationStrict"); else if (i->name == state.sSystem) - drv.platform = state.forceStringNoCtx(*i->value, posDrvName); + drv.platform = state.forceStringNoCtx(*i->value, posDrvName, "while evaluating the `system` attribute passed to builtins.derivationStrict"); else if (i->name == state.sOutputHash) - outputHash = state.forceStringNoCtx(*i->value, posDrvName); + outputHash = state.forceStringNoCtx(*i->value, posDrvName, "while evaluating the `outputHash` attribute passed to builtins.derivationStrict"); else if (i->name == state.sOutputHashAlgo) - outputHashAlgo = state.forceStringNoCtx(*i->value, posDrvName); + outputHashAlgo = state.forceStringNoCtx(*i->value, posDrvName, "while evaluating the `outputHashAlgo` attribute passed to builtins.derivationStrict"); else if (i->name == state.sOutputHashMode) - handleHashMode(state.forceStringNoCtx(*i->value, posDrvName)); + handleHashMode(state.forceStringNoCtx(*i->value, posDrvName, "while evaluating the `outputHashMode` attribute passed to builtins.derivationStrict")); else if (i->name == state.sOutputs) { /* Require ‘outputs’ to be a list of strings. */ - state.forceList(*i->value, posDrvName); + state.forceList(*i->value, posDrvName, "while evaluating the `outputs` attribute passed to builtins.derivationStrict"); Strings ss; for (auto elem : i->value->listItems()) - ss.emplace_back(state.forceStringNoCtx(*elem, posDrvName)); + ss.emplace_back(state.forceStringNoCtx(*elem, posDrvName, "while evaluating an element of the `outputs` attribute passed to builtins.derivationStrict")); handleOutputs(ss); } } else { - auto s = state.coerceToString(*i->pos, *i->value, context, true).toOwned(); + auto s = state.coerceToString(i->pos, *i->value, context, true, "while evaluating an attribute passed to builtins.derivationStrict").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); @@ -1114,16 +1165,16 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * } } catch (Error & e) { - e.addTrace(posDrvName, - "while evaluating the attribute '%1%' of the derivation '%2%'", - key, drvName); + e.addTrace(nullptr, + hintfmt("while evaluating the attribute '%1%' of the derivation '%2%'", key, drvName), + true); throw; } } if (jsonObject) { + drv.env.emplace("__json", jsonObject->dump()); jsonObject.reset(); - drv.env.emplace("__json", jsonBuf.str()); } /* Everything in the context of the strings in the derivation @@ -1165,23 +1216,23 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * /* Do we have all required attributes? */ if (drv.builder == "") - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("required attribute 'builder' missing"), - .errPos = posDrvName - }); + .errPos = state.positions[posDrvName] + })); if (drv.platform == "") - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("required attribute 'system' missing"), - .errPos = posDrvName - }); + .errPos = state.positions[posDrvName] + })); /* Check whether the derivation name is valid. */ if (isDerivation(drvName) && ingestionMethod != ContentAddressMethod { TextHashMethod { } }) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("derivation names are allowed to end in '%s' only if they produce a single derivation file", drvExtension), - .errPos = posDrvName - }); + .errPos = state.positions[posDrvName] + })); if (outputHash) { /* Handle fixed-output derivations. @@ -1189,10 +1240,10 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * Ignore `__contentAddressed` because fixed output derivations are already content addressed. */ if (outputs.size() != 1 || *(outputs.begin()) != "out") - throw Error({ + state.debugThrowLastTrace(Error({ .msg = hintfmt("multiple outputs are not supported in fixed-output derivations"), - .errPos = posDrvName - }); + .errPos = state.positions[posDrvName] + })); auto h = newHashAllowEmpty(*outputHash, parseHashTypeOpt(outputHashAlgo)); @@ -1213,7 +1264,7 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * if (contentAddressed && isImpure) throw EvalError({ .msg = hintfmt("derivation cannot be both content-addressed and impure"), - .errPos = posDrvName + .errPos = state.positions[posDrvName] }); auto ht = parseHashTypeOpt(outputHashAlgo).value_or(htSHA256); @@ -1253,8 +1304,13 @@ static void prim_derivationStrict(EvalState & state, const Pos & pos, Value * * switch (hashModulo.kind) { case DrvHash::Kind::Regular: for (auto & i : outputs) { - auto h = hashModulo.hashes.at(i); - auto outPath = state.store->makeOutputPath(i, h, drvName); + auto h = get(hashModulo.hashes, i); + if (!h) + throw AssertionError({ + .msg = hintfmt("derivation produced no hash for output '%s'", i), + .errPos = state.positions[posDrvName], + }); + auto outPath = state.store->makeOutputPath(i, *h, drvName); drv.env[i] = state.store->printStorePath(outPath); drv.outputs.insert_or_assign( i, @@ -1305,9 +1361,9 @@ static RegisterPrimOp primop_derivationStrict(RegisterPrimOp::Info { time, any occurrence of this string in an derivation attribute will be replaced with the concrete path in the Nix store of the output ‘out’. */ -static void prim_placeholder(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_placeholder(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - v.mkString(hashPlaceholder(state.forceStringNoCtx(*args[0], pos))); + v.mkString(hashPlaceholder(state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.placeholder"))); } static RegisterPrimOp primop_placeholder({ @@ -1328,10 +1384,10 @@ static RegisterPrimOp primop_placeholder({ /* Convert the argument to a path. !!! obsolete? */ -static void prim_toPath(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_toPath(EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - Path path = state.coerceToPath(pos, *args[0], context); + Path path = state.coerceToPath(pos, *args[0], context, "while evaluating the first argument passed to builtins.toPath"); v.mkString(canonPath(path), context); } @@ -1353,25 +1409,25 @@ static RegisterPrimOp primop_toPath({ /nix/store/newhash-oldhash-oldname. In the past, `toPath' had special case behaviour for store paths, but that created weird corner cases. */ -static void prim_storePath(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_storePath(EvalState & state, const PosIdx pos, Value * * args, Value & v) { if (evalSettings.pureEval) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("'%s' is not allowed in pure evaluation mode", "builtins.storePath"), - .errPos = pos - }); + .errPos = state.positions[pos] + })); PathSet context; - Path path = state.checkSourcePath(state.coerceToPath(pos, *args[0], context)); + Path path = state.checkSourcePath(state.coerceToPath(pos, *args[0], context, "while evaluating the first argument passed to builtins.storePath")); /* Resolve symlinks in ‘path’, unless ‘path’ itself is a symlink directly in the store. The latter condition is necessary so e.g. nix-push does the right thing. */ if (!state.store->isStorePath(path)) path = canonPath(path, true); if (!state.store->isInStore(path)) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("path '%1%' is not in the Nix store", path), - .errPos = pos - }); + .errPos = state.positions[pos] + })); auto path2 = state.store->toStorePath(path).first; if (!settings.readOnlyMode) state.store->ensurePath(path2); @@ -1397,13 +1453,13 @@ static RegisterPrimOp primop_storePath({ .fun = prim_storePath, }); -static void prim_pathExists(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_pathExists(EvalState & state, const PosIdx pos, Value * * args, Value & v) { /* We don’t check the path right now, because we don’t want to - throw if the path isn’t allowed, but just return false (and we - can’t just catch the exception here because we still want to - throw if something in the evaluation of `*args[0]` tries to - access an unauthorized path). */ + throw if the path isn’t allowed, but just return false (and we + can’t just catch the exception here because we still want to + throw if something in the evaluation of `*args[0]` tries to + access an unauthorized path). */ auto path = realisePath(state, pos, *args[0], { .checkForPureEval = false }); try { @@ -1429,10 +1485,10 @@ static RegisterPrimOp primop_pathExists({ /* Return the base name of the given string, i.e., everything following the last slash. */ -static void prim_baseNameOf(EvalState & state, const Pos & pos, Value * * args, Value & v) +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)), context); + v.mkString(baseNameOf(*state.coerceToString(pos, *args[0], context, false, false, "while evaluating the first argument passed to builtins.baseNameOf")), context); } static RegisterPrimOp primop_baseNameOf({ @@ -1449,10 +1505,10 @@ static RegisterPrimOp primop_baseNameOf({ /* Return the directory of the given path, i.e., everything before the last slash. Return either a path or a string depending on the type of the argument. */ -static void prim_dirOf(EvalState & state, const Pos & pos, Value * * args, Value & v) +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); + auto path = state.coerceToString(pos, *args[0], context, false, false, "while evaluating the first argument passed to builtins.dirOf"); auto dir = dirOf(*path); if (args[0]->type() == nPath) v.mkPath(dir); else v.mkString(dir, context); } @@ -1469,18 +1525,22 @@ static RegisterPrimOp primop_dirOf({ }); /* Return the contents of a file as a string. */ -static void prim_readFile(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_readFile(EvalState & state, const PosIdx pos, Value * * args, Value & v) { auto path = realisePath(state, pos, *args[0]); auto s = readFile(path); if (s.find((char) 0) != std::string::npos) - throw Error("the contents of the file '%1%' cannot be represented as a Nix string", path); + state.debugThrowLastTrace(Error("the contents of the file '%1%' cannot be represented as a Nix string", path)); StorePathSet refs; if (state.store->isInStore(path)) { try { refs = state.store->queryPathInfo(state.store->toStorePath(path).first)->references; } catch (Error &) { // FIXME: should be InvalidPathError } + // Re-scan references to filter down to just the ones that actually occur in the file. + auto refsSink = PathRefScanSink::fromPaths(refs); + refsSink << s; + refs = refsSink.getResultPaths(); } auto context = state.store->printStorePathSet(refs); v.mkString(s, context); @@ -1497,46 +1557,40 @@ static RegisterPrimOp primop_readFile({ /* Find a file in the Nix search path. Used to implement <x> paths, which are desugared to 'findFile __nixPath "x"'. */ -static void prim_findFile(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_findFile(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceList(*args[0], pos); + state.forceList(*args[0], pos, "while evaluating the first argument passed to builtins.findFile"); SearchPath searchPath; for (auto v2 : args[0]->listItems()) { - state.forceAttrs(*v2, pos); + state.forceAttrs(*v2, pos, "while evaluating an element of the list passed to builtins.findFile"); std::string prefix; Bindings::iterator i = v2->attrs->find(state.sPrefix); if (i != v2->attrs->end()) - prefix = state.forceStringNoCtx(*i->value, pos); + prefix = state.forceStringNoCtx(*i->value, pos, "while evaluating the `prefix` attribute of an element of the list passed to builtins.findFile"); - i = getAttr( - state, - "findFile", - state.sPath, - v2->attrs, - pos - ); + 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).toOwned(); + 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(); try { auto rewrites = state.realiseContext(context); path = rewriteStrings(path, rewrites); } catch (InvalidPathError & e) { - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("cannot find '%1%', since path '%2%' is not valid", path, e.path), - .errPos = pos - }); + .errPos = state.positions[pos] + })); } - searchPath.emplace_back(prefix, path); } - auto path = state.forceStringNoCtx(*args[1], pos); + auto path = state.forceStringNoCtx(*args[1], pos, "while evaluating the second argument passed to builtins.findFile"); v.mkPath(state.checkSourcePath(state.findFile(searchPath, path, pos))); } @@ -1548,15 +1602,15 @@ static RegisterPrimOp primop_findFile(RegisterPrimOp::Info { }); /* Return the cryptographic hash of a file in base-16. */ -static void prim_hashFile(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_hashFile(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto type = state.forceStringNoCtx(*args[0], pos); + auto type = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.hashFile"); std::optional<HashType> ht = parseHashType(type); if (!ht) - throw Error({ + state.debugThrowLastTrace(Error({ .msg = hintfmt("unknown hash type '%1%'", type), - .errPos = pos - }); + .errPos = state.positions[pos] + })); auto path = realisePath(state, pos, *args[1]); @@ -1575,7 +1629,7 @@ static RegisterPrimOp primop_hashFile({ }); /* Read a directory (without . or ..) */ -static void prim_readDir(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_readDir(EvalState & state, const PosIdx pos, Value * * args, Value & v) { auto path = realisePath(state, pos, *args[0]); @@ -1624,7 +1678,7 @@ static RegisterPrimOp primop_readDir({ /* Convert the argument (which can be any Nix expression) to an XML representation returned in a string. Not all Nix expressions can be sensibly or completely represented (e.g., functions). */ -static void prim_toXML(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_toXML(EvalState & state, const PosIdx pos, Value * * args, Value & v) { std::ostringstream out; PathSet context; @@ -1732,7 +1786,7 @@ static RegisterPrimOp primop_toXML({ /* Convert the argument (which can be any Nix expression) to a JSON string. Not all Nix expressions can be sensibly or completely represented (e.g., functions). */ -static void prim_toJSON(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_toJSON(EvalState & state, const PosIdx pos, Value * * args, Value & v) { std::ostringstream out; PathSet context; @@ -1755,13 +1809,13 @@ static RegisterPrimOp primop_toJSON({ }); /* Parse a JSON string to a value. */ -static void prim_fromJSON(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_fromJSON(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto s = state.forceStringNoCtx(*args[0], pos); + auto s = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.fromJSON"); try { parseJSON(state, s, v); } catch (JSONParseError &e) { - e.addTrace(pos, "while decoding a JSON string"); + e.addTrace(state.positions[pos], "while decoding a JSON string"); throw; } } @@ -1783,35 +1837,36 @@ static RegisterPrimOp primop_fromJSON({ /* Store a string in the Nix store as a source file that can be used as an input by derivations. */ -static void prim_toFile(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_toFile(EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - std::string name(state.forceStringNoCtx(*args[0], pos)); - std::string contents(state.forceString(*args[1], context, pos)); + std::string name(state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.toFile")); + std::string contents(state.forceString(*args[1], context, pos, "while evaluating the second argument passed to builtins.toFile")); StorePathSet refs; for (auto path : context) { if (path.at(0) != '/') - throw EvalError( { + state.debugThrowLastTrace(EvalError({ .msg = hintfmt( "in 'toFile': the file named '%1%' must not contain a reference " "to a derivation but contains (%2%)", name, path), - .errPos = pos - }); + .errPos = state.positions[pos] + })); refs.insert(state.store->parseStorePath(path)); } - auto storePath = state.store->printStorePath(settings.readOnlyMode + auto storePath = settings.readOnlyMode ? state.store->computeStorePathForText(name, contents, refs) - : state.store->addTextToStore(name, contents, refs, state.repair)); + : state.store->addTextToStore(name, contents, refs, state.repair); /* Note: we don't need to add `context' to the context of the result, since `storePath' itself has references to the paths used in args[1]. */ - v.mkString(storePath, {storePath}); + /* Add the output of this to the allowed paths. */ + state.allowAndSetStorePathString(storePath, v); } static RegisterPrimOp primop_toFile({ @@ -1866,8 +1921,8 @@ static RegisterPrimOp primop_toFile({ "; ``` - Note that `${configFile}` is an - [antiquotation](language-values.md), so the result of the + Note that `${configFile}` is a + [string interpolation](language/values.md#type-string), so the result of the expression `configFile` (i.e., a path like `/nix/store/m7p7jfny445k...-foo.conf`) will be spliced into the resulting string. @@ -1894,7 +1949,7 @@ static RegisterPrimOp primop_toFile({ static void addPath( EvalState & state, - const Pos & pos, + const PosIdx pos, const std::string & name, Path path, Value * filterFun, @@ -1944,7 +1999,7 @@ static void addPath( Value res; state.callFunction(*filterFun, 2, args, res, pos); - return state.forceBool(res, pos); + return state.forceBool(res, pos, "while evaluating the return value of the path filter function"); }) : defaultPathFilter; std::optional<StorePath> expectedStorePath; @@ -1962,31 +2017,22 @@ static void addPath( ? state.store->computeStorePathForPath(name, path, method, htSHA256, filter).first : state.store->addToStore(name, path, method, htSHA256, filter, state.repair, refs); if (expectedHash && expectedStorePath != dstPath) - throw Error("store path mismatch in (possibly filtered) path added from '%s'", path); + state.debugThrowLastTrace(Error("store path mismatch in (possibly filtered) path added from '%s'", path)); state.allowAndSetStorePathString(dstPath, v); } else state.allowAndSetStorePathString(*expectedStorePath, v); } catch (Error & e) { - e.addTrace(pos, "while adding path '%s'", path); + e.addTrace(state.positions[pos], "while adding path '%s'", path); throw; } } -static void prim_filterSource(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_filterSource(EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - Path path = state.coerceToPath(pos, *args[1], context); - - state.forceValue(*args[0], pos); - if (args[0]->type() != nFunction) - throw TypeError({ - .msg = hintfmt( - "first argument in call to 'filterSource' is not a function but %1%", - showType(*args[0])), - .errPos = pos - }); - + Path path = state.coerceToPath(pos, *args[1], context, "while evaluating the second argument (the path to filter) passed to builtins.filterSource"); + state.forceFunction(*args[0], pos, "while evaluating the first argument passed to builtins.filterSource"); addPath(state, pos, std::string(baseNameOf(path)), path, args[0], FileIngestionMethod::Recursive, std::nullopt, v, context); } @@ -2045,9 +2091,9 @@ static RegisterPrimOp primop_filterSource({ .fun = prim_filterSource, }); -static void prim_path(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_path(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceAttrs(*args[0], pos); + state.forceAttrs(*args[0], pos, "while evaluating the argument passed to builtins.path"); Path path; std::string name; Value * filterFun = nullptr; @@ -2056,29 +2102,28 @@ static void prim_path(EvalState & state, const Pos & pos, Value * * args, Value PathSet context; for (auto & attr : *args[0]->attrs) { - auto & n(attr.name); + auto n = state.symbols[attr.name]; if (n == "path") - path = state.coerceToPath(*attr.pos, *attr.value, context); + path = state.coerceToPath(attr.pos, *attr.value, context, "while evaluating the `path` attribute passed to builtins.path"); else if (attr.name == state.sName) - name = state.forceStringNoCtx(*attr.value, *attr.pos); - else if (n == "filter") { - state.forceValue(*attr.value, pos); - filterFun = attr.value; - } else if (n == "recursive") - method = FileIngestionMethod { state.forceBool(*attr.value, *attr.pos) }; + name = state.forceStringNoCtx(*attr.value, attr.pos, "while evaluating the `name` attribute passed to builtins.path"); + else if (n == "filter") + state.forceFunction(*(filterFun = attr.value), attr.pos, "while evaluating the `filter` parameter passed to builtins.path"); + else if (n == "recursive") + method = FileIngestionMethod { state.forceBool(*attr.value, attr.pos, "while evaluating the `recursive` attribute passed to builtins.path") }; else if (n == "sha256") - expectedHash = newHashAllowEmpty(state.forceStringNoCtx(*attr.value, *attr.pos), htSHA256); + expectedHash = newHashAllowEmpty(state.forceStringNoCtx(*attr.value, attr.pos, "while evaluating the `sha256` attribute passed to builtins.path"), htSHA256); else - throw EvalError({ - .msg = hintfmt("unsupported argument '%1%' to 'addPath'", attr.name), - .errPos = *attr.pos - }); + state.debugThrowLastTrace(EvalError({ + .msg = hintfmt("unsupported argument '%1%' to 'addPath'", state.symbols[attr.name]), + .errPos = state.positions[attr.pos] + })); } if (path.empty()) - throw EvalError({ - .msg = hintfmt("'path' required"), - .errPos = pos - }); + state.debugThrowLastTrace(EvalError({ + .msg = hintfmt("missing required 'path' attribute in the first argument to builtins.path"), + .errPos = state.positions[pos] + })); if (name.empty()) name = baseNameOf(path); @@ -2128,15 +2173,15 @@ static RegisterPrimOp primop_path({ /* Return the names of the attributes in a set as a sorted list of strings. */ -static void prim_attrNames(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_attrNames(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceAttrs(*args[0], pos); + state.forceAttrs(*args[0], pos, "while evaluating the argument passed to builtins.attrNames"); state.mkList(v, args[0]->attrs->size()); size_t n = 0; for (auto & i : *args[0]->attrs) - (v.listElems()[n++] = state.allocValue())->mkString(i.name); + (v.listElems()[n++] = state.allocValue())->mkString(state.symbols[i.name]); std::sort(v.listElems(), v.listElems() + n, [](Value * v1, Value * v2) { return strcmp(v1->string.s, v2->string.s) < 0; }); @@ -2155,9 +2200,9 @@ static RegisterPrimOp primop_attrNames({ /* Return the values of the attributes in a set as a list, in the same order as attrNames. */ -static void prim_attrValues(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_attrValues(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceAttrs(*args[0], pos); + state.forceAttrs(*args[0], pos, "while evaluating the argument passed to builtins.attrValues"); state.mkList(v, args[0]->attrs->size()); @@ -2166,8 +2211,9 @@ static void prim_attrValues(EvalState & state, const Pos & pos, Value * * args, v.listElems()[n++] = (Value *) &i; std::sort(v.listElems(), v.listElems() + n, - [](Value * v1, Value * v2) { - std::string_view s1 = ((Attr *) v1)->name, s2 = ((Attr *) v2)->name; + [&](Value * v1, Value * v2) { + std::string_view s1 = state.symbols[((Attr *) v1)->name], + s2 = state.symbols[((Attr *) v2)->name]; return s1 < s2; }); @@ -2186,19 +2232,18 @@ static RegisterPrimOp primop_attrValues({ }); /* Dynamic version of the `.' operator. */ -void prim_getAttr(EvalState & state, const Pos & pos, Value * * args, Value & v) +void prim_getAttr(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto attr = state.forceStringNoCtx(*args[0], pos); - state.forceAttrs(*args[1], pos); + auto attr = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.getAttr"); + state.forceAttrs(*args[1], pos, "while evaluating the second argument passed to builtins.getAttr"); Bindings::iterator i = getAttr( state, - "getAttr", state.symbols.create(attr), args[1]->attrs, - pos + "in the attribute set under consideration" ); // !!! add to stack trace? - if (state.countCalls && *i->pos != noPos) state.attrSelects[*i->pos]++; + if (state.countCalls && i->pos) state.attrSelects[i->pos]++; state.forceValue(*i->value, pos); v = *i->value; } @@ -2216,10 +2261,10 @@ static RegisterPrimOp primop_getAttr({ }); /* Return position information of the specified attribute. */ -static void prim_unsafeGetAttrPos(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_unsafeGetAttrPos(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto attr = state.forceStringNoCtx(*args[0], pos); - state.forceAttrs(*args[1], pos); + auto attr = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.unsafeGetAttrPos"); + state.forceAttrs(*args[1], pos, "while evaluating the second argument passed to builtins.unsafeGetAttrPos"); Bindings::iterator i = args[1]->attrs->find(state.symbols.create(attr)); if (i == args[1]->attrs->end()) v.mkNull(); @@ -2234,10 +2279,10 @@ static RegisterPrimOp primop_unsafeGetAttrPos(RegisterPrimOp::Info { }); /* Dynamic version of the `?' operator. */ -static void prim_hasAttr(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_hasAttr(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto attr = state.forceStringNoCtx(*args[0], pos); - state.forceAttrs(*args[1], pos); + auto attr = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.hasAttr"); + state.forceAttrs(*args[1], pos, "while evaluating the second argument passed to builtins.hasAttr"); v.mkBool(args[1]->attrs->find(state.symbols.create(attr)) != args[1]->attrs->end()); } @@ -2253,7 +2298,7 @@ static RegisterPrimOp primop_hasAttr({ }); /* Determine whether the argument is a set. */ -static void prim_isAttrs(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_isAttrs(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); v.mkBool(args[0]->type() == nAttrs); @@ -2268,10 +2313,10 @@ static RegisterPrimOp primop_isAttrs({ .fun = prim_isAttrs, }); -static void prim_removeAttrs(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_removeAttrs(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceAttrs(*args[0], pos); - state.forceList(*args[1], pos); + state.forceAttrs(*args[0], pos, "while evaluating the first argument passed to builtins.removeAttrs"); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.removeAttrs"); /* Get the attribute names to be removed. We keep them as Attrs instead of Symbols so std::set_difference @@ -2279,7 +2324,7 @@ static void prim_removeAttrs(EvalState & state, const Pos & pos, Value * * args, boost::container::small_vector<Attr, 64> names; names.reserve(args[1]->listSize()); for (auto elem : args[1]->listItems()) { - state.forceStringNoCtx(*elem, pos); + state.forceStringNoCtx(*elem, pos, "while evaluating the values of the second argument passed to builtins.removeAttrs"); names.emplace_back(state.symbols.create(elem->string.s), nullptr); } std::sort(names.begin(), names.end()); @@ -2316,36 +2361,24 @@ static RegisterPrimOp primop_removeAttrs({ "nameN"; value = valueN;}] is transformed to {name1 = value1; ... nameN = valueN;}. In case of duplicate occurrences of the same name, the first takes precedence. */ -static void prim_listToAttrs(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_listToAttrs(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceList(*args[0], pos); + state.forceList(*args[0], pos, "while evaluating the argument passed to builtins.listToAttrs"); auto attrs = state.buildBindings(args[0]->listSize()); std::set<Symbol> seen; for (auto v2 : args[0]->listItems()) { - state.forceAttrs(*v2, pos); + state.forceAttrs(*v2, pos, "while evaluating an element of the list passed to builtins.listToAttrs"); - Bindings::iterator j = getAttr( - state, - "listToAttrs", - state.sName, - v2->attrs, - pos - ); + Bindings::iterator j = getAttr(state, state.sName, v2->attrs, "in a {name=...; value=...;} pair"); - auto name = state.forceStringNoCtx(*j->value, *j->pos); + auto name = state.forceStringNoCtx(*j->value, j->pos, "while evaluating the `name` attribute of an element of the list passed to builtins.listToAttrs"); - Symbol sym = state.symbols.create(name); + auto sym = state.symbols.create(name); if (seen.insert(sym).second) { - Bindings::iterator j2 = getAttr( - state, - "listToAttrs", - state.sValue, - v2->attrs, - pos - ); + Bindings::iterator j2 = getAttr(state, state.sValue, v2->attrs, "in a {name=...; value=...;} pair"); attrs.insert(sym, j2->value, j2->pos); } } @@ -2360,12 +2393,18 @@ static RegisterPrimOp primop_listToAttrs({ Construct a set from a list specifying the names and values of each attribute. Each element of the list should be a set consisting of a string-valued attribute `name` specifying the name of the attribute, - and an attribute `value` specifying its value. Example: + and an attribute `value` specifying its value. + + In case of duplicate occurrences of the same name, the first + takes precedence. + + Example: ```nix builtins.listToAttrs [ { name = "foo"; value = 123; } { name = "bar"; value = 456; } + { name = "bar"; value = 420; } ] ``` @@ -2378,17 +2417,67 @@ static RegisterPrimOp primop_listToAttrs({ .fun = prim_listToAttrs, }); -static void prim_intersectAttrs(EvalState & state, const Pos & pos, Value * * args, Value & v) -{ - state.forceAttrs(*args[0], pos); - state.forceAttrs(*args[1], pos); - - auto attrs = state.buildBindings(std::min(args[0]->attrs->size(), args[1]->attrs->size())); - - for (auto & i : *args[0]->attrs) { - Bindings::iterator j = args[1]->attrs->find(i.name); - if (j != args[1]->attrs->end()) - attrs.insert(*j); +static void prim_intersectAttrs(EvalState & state, const PosIdx pos, Value * * args, Value & v) +{ + state.forceAttrs(*args[0], pos, "while evaluating the first argument passed to builtins.intersectAttrs"); + state.forceAttrs(*args[1], pos, "while evaluating the second argument passed to builtins.intersectAttrs"); + + Bindings &left = *args[0]->attrs; + Bindings &right = *args[1]->attrs; + + auto attrs = state.buildBindings(std::min(left.size(), right.size())); + + // The current implementation has good asymptotic complexity and is reasonably + // simple. Further optimization may be possible, but does not seem productive, + // considering the state of eval performance in 2022. + // + // I have looked for reusable and/or standard solutions and these are my + // findings: + // + // STL + // === + // std::set_intersection is not suitable, as it only performs a simultaneous + // linear scan; not taking advantage of random access. This is O(n + m), so + // linear in the largest set, which is not acceptable for callPackage in Nixpkgs. + // + // Simultaneous scan, with alternating simple binary search + // === + // One alternative algorithm scans the attrsets simultaneously, jumping + // forward using `lower_bound` in case of inequality. This should perform + // well on very similar sets, having a local and predictable access pattern. + // On dissimilar sets, it seems to need more comparisons than the current + // algorithm, as few consecutive attrs match. `lower_bound` could take + // advantage of the decreasing remaining search space, but this causes + // the medians to move, which can mean that they don't stay in the cache + // like they would with the current naive `find`. + // + // Double binary search + // === + // The optimal algorithm may be "Double binary search", which doesn't + // scan at all, but rather divides both sets simultaneously. + // See "Fast Intersection Algorithms for Sorted Sequences" by Baeza-Yates et al. + // https://cs.uwaterloo.ca/~ajsaling/papers/intersection_alg_app10.pdf + // The only downsides I can think of are not having a linear access pattern + // for similar sets, and having to maintain a more intricate algorithm. + // + // Adaptive + // === + // Finally one could run try a simultaneous scan, count misses and fall back + // to double binary search when the counter hit some threshold and/or ratio. + + if (left.size() < right.size()) { + for (auto & l : left) { + Bindings::iterator r = right.find(l.name); + if (r != right.end()) + attrs.insert(*r); + } + } + else { + for (auto & r : right) { + Bindings::iterator l = left.find(r.name); + if (l != left.end()) + attrs.insert(r); + } } v.mkAttrs(attrs.alreadySorted()); @@ -2398,22 +2487,24 @@ static RegisterPrimOp primop_intersectAttrs({ .name = "__intersectAttrs", .args = {"e1", "e2"}, .doc = R"( - Return a set consisting of the attributes in the set *e2* that also - exist in the set *e1*. + Return a set consisting of the attributes in the set *e2* which have the + same name as some attribute in *e1*. + + Performs in O(*n* log *m*) where *n* is the size of the smaller set and *m* the larger set's size. )", .fun = prim_intersectAttrs, }); -static void prim_catAttrs(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_catAttrs(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - Symbol attrName = state.symbols.create(state.forceStringNoCtx(*args[0], pos)); - state.forceList(*args[1], pos); + auto attrName = state.symbols.create(state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.catAttrs")); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.catAttrs"); Value * res[args[1]->listSize()]; unsigned int found = 0; for (auto v2 : args[1]->listItems()) { - state.forceAttrs(*v2, pos); + state.forceAttrs(*v2, pos, "while evaluating an element in the list passed as second argument to builtins.catAttrs"); Bindings::iterator i = v2->attrs->find(attrName); if (i != v2->attrs->end()) res[found++] = i->value; @@ -2441,7 +2532,7 @@ static RegisterPrimOp primop_catAttrs({ .fun = prim_catAttrs, }); -static void prim_functionArgs(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_functionArgs(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); if (args[0]->isPrimOpApp() || args[0]->isPrimOp()) { @@ -2449,10 +2540,10 @@ static void prim_functionArgs(EvalState & state, const Pos & pos, Value * * args return; } if (!args[0]->isLambda()) - throw TypeError({ + state.debugThrowLastTrace(TypeError({ .msg = hintfmt("'functionArgs' requires a function"), - .errPos = pos - }); + .errPos = state.positions[pos] + })); if (!args[0]->lambda.fun->hasFormals()) { v.mkAttrs(&state.emptyBindings); @@ -2462,7 +2553,7 @@ static void prim_functionArgs(EvalState & state, const Pos & pos, Value * * args auto attrs = state.buildBindings(args[0]->lambda.fun->formals->formals.size()); for (auto & i : args[0]->lambda.fun->formals->formals) // !!! should optimise booleans (allocate only once) - attrs.alloc(i.name, ptr(&i.pos)).mkBool(i.def); + attrs.alloc(i.name, i.pos).mkBool(i.def); v.mkAttrs(attrs); } @@ -2484,16 +2575,16 @@ static RegisterPrimOp primop_functionArgs({ }); /* */ -static void prim_mapAttrs(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_mapAttrs(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceAttrs(*args[1], pos); + state.forceAttrs(*args[1], pos, "while evaluating the second argument passed to builtins.mapAttrs"); auto attrs = state.buildBindings(args[1]->attrs->size()); for (auto & i : *args[1]->attrs) { Value * vName = state.allocValue(); Value * vFun2 = state.allocValue(); - vName->mkString(i.name); + vName->mkString(state.symbols[i.name]); vFun2->mkApp(args[0], vName); attrs.alloc(i.name).mkApp(vFun2, i.value); } @@ -2516,7 +2607,7 @@ static RegisterPrimOp primop_mapAttrs({ .fun = prim_mapAttrs, }); -static void prim_zipAttrsWith(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_zipAttrsWith(EvalState & state, const PosIdx pos, Value * * args, Value & v) { // we will first count how many values are present for each given key. // we then allocate a single attrset and pre-populate it with lists of @@ -2527,20 +2618,20 @@ static void prim_zipAttrsWith(EvalState & state, const Pos & pos, Value * * args std::map<Symbol, std::pair<size_t, Value * *>> attrsSeen; - state.forceFunction(*args[0], pos); - state.forceList(*args[1], pos); + state.forceFunction(*args[0], pos, "while evaluating the first argument passed to builtins.zipAttrsWith"); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.zipAttrsWith"); const auto listSize = args[1]->listSize(); const auto listElems = args[1]->listElems(); for (unsigned int n = 0; n < listSize; ++n) { Value * vElem = listElems[n]; try { - state.forceAttrs(*vElem, noPos); + 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(pos, hintfmt("while invoking '%s'", "zipAttrsWith")); - throw; + e.addTrace(state.positions[pos], hintfmt("while invoking '%s'", "zipAttrsWith")); + state.debugThrowLastTrace(e); } } @@ -2560,7 +2651,7 @@ static void prim_zipAttrsWith(EvalState & state, const Pos & pos, Value * * args for (auto & attr : *v.attrs) { auto name = state.allocValue(); - name->mkString(attr.name); + name->mkString(state.symbols[attr.name]); auto call1 = state.allocValue(); call1->mkApp(args[0], name); auto call2 = state.allocValue(); @@ -2608,7 +2699,7 @@ static RegisterPrimOp primop_zipAttrsWith({ /* Determine whether the argument is a list. */ -static void prim_isList(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_isList(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); v.mkBool(args[0]->type() == nList); @@ -2623,22 +2714,22 @@ static RegisterPrimOp primop_isList({ .fun = prim_isList, }); -static void elemAt(EvalState & state, const Pos & pos, Value & list, int n, Value & v) +static void elemAt(EvalState & state, const PosIdx pos, Value & list, int n, Value & v) { - state.forceList(list, pos); + state.forceList(list, pos, "while evaluating the first argument passed to builtins.elemAt"); if (n < 0 || (unsigned int) n >= list.listSize()) - throw Error({ + state.debugThrowLastTrace(Error({ .msg = hintfmt("list index %1% is out of bounds", n), - .errPos = pos - }); + .errPos = state.positions[pos] + })); state.forceValue(*list.listElems()[n], pos); v = *list.listElems()[n]; } /* Return the n-1'th element of a list. */ -static void prim_elemAt(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_elemAt(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - elemAt(state, pos, *args[0], state.forceInt(*args[1], pos), v); + elemAt(state, pos, *args[0], state.forceInt(*args[1], pos, "while evaluating the second argument passed to builtins.elemAt"), v); } static RegisterPrimOp primop_elemAt({ @@ -2652,7 +2743,7 @@ static RegisterPrimOp primop_elemAt({ }); /* Return the first element of a list. */ -static void prim_head(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_head(EvalState & state, const PosIdx pos, Value * * args, Value & v) { elemAt(state, pos, *args[0], 0, v); } @@ -2671,14 +2762,14 @@ static RegisterPrimOp primop_head({ /* Return a list consisting of everything but the first element of a list. Warning: this function takes O(n) time, so you probably don't want to use it! */ -static void prim_tail(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_tail(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceList(*args[0], pos); + state.forceList(*args[0], pos, "while evaluating the first argument passed to builtins.tail"); if (args[0]->listSize() == 0) - throw Error({ + state.debugThrowLastTrace(Error({ .msg = hintfmt("'tail' called on an empty list"), - .errPos = pos - }); + .errPos = state.positions[pos] + })); state.mkList(v, args[0]->listSize() - 1); for (unsigned int n = 0; n < v.listSize(); ++n) @@ -2702,12 +2793,18 @@ static RegisterPrimOp primop_tail({ }); /* Apply a function to every element of a list. */ -static void prim_map(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_map(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceList(*args[1], pos); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.map"); - state.mkList(v, args[1]->listSize()); + if (args[1]->listSize() == 0) { + v = *args[1]; + return; + } + + state.forceFunction(*args[0], pos, "while evaluating the first argument passed to builtins.map"); + state.mkList(v, args[1]->listSize()); for (unsigned int n = 0; n < v.listSize(); ++n) (v.listElems()[n] = state.allocValue())->mkApp( args[0], args[1]->listElems()[n]); @@ -2721,7 +2818,7 @@ static RegisterPrimOp primop_map({ example, ```nix - map (x: "foo" + x) [ "bar" "bla" "abc" ] + map (x"foo" + x) [ "bar" "bla" "abc" ] ``` evaluates to `[ "foobar" "foobla" "fooabc" ]`. @@ -2732,10 +2829,16 @@ static RegisterPrimOp primop_map({ /* Filter a list using a predicate; that is, return a list containing every element from the list for which the predicate function returns true. */ -static void prim_filter(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_filter(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceFunction(*args[0], pos); - state.forceList(*args[1], pos); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.filter"); + + if (args[1]->listSize() == 0) { + v = *args[1]; + return; + } + + state.forceFunction(*args[0], pos, "while evaluating the first argument passed to builtins.filter"); // FIXME: putting this on the stack is risky. Value * vs[args[1]->listSize()]; @@ -2745,7 +2848,7 @@ static void prim_filter(EvalState & state, const Pos & pos, Value * * args, Valu for (unsigned int n = 0; n < args[1]->listSize(); ++n) { Value res; state.callFunction(*args[0], *args[1]->listElems()[n], res, noPos); - if (state.forceBool(res, pos)) + if (state.forceBool(res, pos, "while evaluating the return value of the filtering function passed to builtins.filter")) vs[k++] = args[1]->listElems()[n]; else same = false; @@ -2770,12 +2873,12 @@ static RegisterPrimOp primop_filter({ }); /* Return true if a list contains a given element. */ -static void prim_elem(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_elem(EvalState & state, const PosIdx pos, Value * * args, Value & v) { bool res = false; - state.forceList(*args[1], pos); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.elem"); for (auto elem : args[1]->listItems()) - if (state.eqValues(*args[0], *elem)) { + if (state.eqValues(*args[0], *elem, pos, "while searching for the presence of the given element in the list")) { res = true; break; } @@ -2793,10 +2896,10 @@ static RegisterPrimOp primop_elem({ }); /* Concatenate a list of lists. */ -static void prim_concatLists(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_concatLists(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceList(*args[0], pos); - state.concatLists(v, args[0]->listSize(), args[0]->listElems(), pos); + state.forceList(*args[0], pos, "while evaluating the first argument passed to builtins.concatLists"); + state.concatLists(v, args[0]->listSize(), args[0]->listElems(), pos, "while evaluating a value of the list passed to builtins.concatLists"); } static RegisterPrimOp primop_concatLists({ @@ -2809,9 +2912,9 @@ static RegisterPrimOp primop_concatLists({ }); /* Return the length of a list. This is an O(1) time operation. */ -static void prim_length(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_length(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceList(*args[0], pos); + state.forceList(*args[0], pos, "while evaluating the first argument passed to builtins.length"); v.mkInt(args[0]->listSize()); } @@ -2826,10 +2929,10 @@ static RegisterPrimOp primop_length({ /* Reduce a list by applying a binary operator, from left to right. The operator is applied strictly. */ -static void prim_foldlStrict(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_foldlStrict(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceFunction(*args[0], pos); - state.forceList(*args[2], pos); + state.forceFunction(*args[0], pos, "while evaluating the first argument passed to builtins.foldlStrict"); + state.forceList(*args[2], pos, "while evaluating the third argument passed to builtins.foldlStrict"); if (args[2]->listSize()) { Value * vCur = args[1]; @@ -2859,15 +2962,15 @@ static RegisterPrimOp primop_foldlStrict({ .fun = prim_foldlStrict, }); -static void anyOrAll(bool any, EvalState & state, const Pos & pos, Value * * args, Value & v) +static void anyOrAll(bool any, EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceFunction(*args[0], pos); - state.forceList(*args[1], pos); + state.forceFunction(*args[0], pos, std::string("while evaluating the first argument passed to builtins.") + (any ? "any" : "all")); + state.forceList(*args[1], pos, std::string("while evaluating the second argument passed to builtins.") + (any ? "any" : "all")); Value vTmp; for (auto elem : args[1]->listItems()) { state.callFunction(*args[0], *elem, vTmp, pos); - bool res = state.forceBool(vTmp, pos); + bool res = state.forceBool(vTmp, pos, std::string("while evaluating the return value of the function passed to builtins.") + (any ? "any" : "all")); if (res == any) { v.mkBool(any); return; @@ -2878,7 +2981,7 @@ static void anyOrAll(bool any, EvalState & state, const Pos & pos, Value * * arg } -static void prim_any(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_any(EvalState & state, const PosIdx pos, Value * * args, Value & v) { anyOrAll(true, state, pos, args, v); } @@ -2893,7 +2996,7 @@ static RegisterPrimOp primop_any({ .fun = prim_any, }); -static void prim_all(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_all(EvalState & state, const PosIdx pos, Value * * args, Value & v) { anyOrAll(false, state, pos, args, v); } @@ -2908,15 +3011,15 @@ static RegisterPrimOp primop_all({ .fun = prim_all, }); -static void prim_genList(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_genList(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto len = state.forceInt(*args[1], pos); + auto len = state.forceInt(*args[1], pos, "while evaluating the second argument passed to builtins.genList"); if (len < 0) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("cannot create list of size %1%", len), - .errPos = pos - }); + .errPos = state.positions[pos] + })); state.mkList(v, len); @@ -2943,15 +3046,21 @@ static RegisterPrimOp primop_genList({ .fun = prim_genList, }); -static void prim_lessThan(EvalState & state, const Pos & pos, Value * * args, Value & v); +static void prim_lessThan(EvalState & state, const PosIdx pos, Value * * args, Value & v); -static void prim_sort(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_sort(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceFunction(*args[0], pos); - state.forceList(*args[1], pos); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.sort"); auto len = args[1]->listSize(); + if (len == 0) { + v = *args[1]; + return; + } + + state.forceFunction(*args[0], pos, "while evaluating the first argument passed to builtins.sort"); + state.mkList(v, len); for (unsigned int n = 0; n < len; ++n) { state.forceValue(*args[1]->listElems()[n], pos); @@ -2962,12 +3071,12 @@ static void prim_sort(EvalState & state, const Pos & pos, Value * * args, Value /* Optimization: if the comparator is lessThan, bypass callFunction. */ if (args[0]->isPrimOp() && args[0]->primOp->fun == prim_lessThan) - return CompareValues(state)(a, b); + return CompareValues(state, noPos, "while evaluating the ordering function passed to builtins.sort")(a, b); Value * vs[] = {a, b}; Value vBool; - state.callFunction(*args[0], 2, vs, vBool, pos); - return state.forceBool(vBool, pos); + state.callFunction(*args[0], 2, vs, vBool, noPos); + return state.forceBool(vBool, pos, "while evaluating the return value of the sorting function passed to builtins.sort"); }; /* FIXME: std::sort can segfault if the comparator is not a strict @@ -2997,10 +3106,10 @@ static RegisterPrimOp primop_sort({ .fun = prim_sort, }); -static void prim_partition(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_partition(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceFunction(*args[0], pos); - state.forceList(*args[1], pos); + state.forceFunction(*args[0], pos, "while evaluating the first argument passed to builtins.partition"); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.partition"); auto len = args[1]->listSize(); @@ -3011,7 +3120,7 @@ static void prim_partition(EvalState & state, const Pos & pos, Value * * args, V state.forceValue(*vElem, pos); Value res; state.callFunction(*args[0], *vElem, res, pos); - if (state.forceBool(res, pos)) + if (state.forceBool(res, pos, "while evaluating the return value of the partition function passed to builtins.partition")) right.push_back(vElem); else wrong.push_back(vElem); @@ -3057,18 +3166,18 @@ static RegisterPrimOp primop_partition({ .fun = prim_partition, }); -static void prim_groupBy(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_groupBy(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceFunction(*args[0], pos); - state.forceList(*args[1], pos); + state.forceFunction(*args[0], pos, "while evaluating the first argument passed to builtins.groupBy"); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.groupBy"); ValueVectorMap attrs; for (auto vElem : args[1]->listItems()) { Value res; state.callFunction(*args[0], *vElem, res, pos); - auto name = state.forceStringNoCtx(res, pos); - Symbol sym = state.symbols.create(name); + auto name = state.forceStringNoCtx(res, pos, "while evaluating the return value of the grouping function passed to builtins.groupBy"); + auto sym = state.symbols.create(name); auto vector = attrs.try_emplace(sym, ValueVector()).first; vector->second.push_back(vElem); } @@ -3109,10 +3218,10 @@ static RegisterPrimOp primop_groupBy({ .fun = prim_groupBy, }); -static void prim_concatMap(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_concatMap(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceFunction(*args[0], pos); - state.forceList(*args[1], pos); + state.forceFunction(*args[0], pos, "while evaluating the first argument passed to builtins.concatMap"); + state.forceList(*args[1], pos, "while evaluating the second argument passed to builtins.concatMap"); auto nrLists = args[1]->listSize(); Value lists[nrLists]; @@ -3122,10 +3231,10 @@ static void prim_concatMap(EvalState & state, const Pos & pos, Value * * args, V 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))); + 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(pos, hintfmt("while invoking '%s'", "concatMap")); - throw; + e.addTrace(state.positions[pos], hintfmt("while invoking '%s'", "concatMap")); + state.debugThrowLastTrace(e); } len += lists[n].listSize(); } @@ -3156,14 +3265,16 @@ static RegisterPrimOp primop_concatMap({ *************************************************************/ -static void prim_add(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_add(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); state.forceValue(*args[1], pos); if (args[0]->type() == nFloat || args[1]->type() == nFloat) - v.mkFloat(state.forceFloat(*args[0], pos) + state.forceFloat(*args[1], pos)); + v.mkFloat(state.forceFloat(*args[0], pos, "while evaluating the first argument of the addition") + + state.forceFloat(*args[1], pos, "while evaluating the second argument of the addition")); else - v.mkInt(state.forceInt(*args[0], pos) + state.forceInt(*args[1], pos)); + v.mkInt( state.forceInt(*args[0], pos, "while evaluating the first argument of the addition") + + state.forceInt(*args[1], pos, "while evaluating the second argument of the addition")); } static RegisterPrimOp primop_add({ @@ -3175,14 +3286,16 @@ static RegisterPrimOp primop_add({ .fun = prim_add, }); -static void prim_sub(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_sub(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); state.forceValue(*args[1], pos); if (args[0]->type() == nFloat || args[1]->type() == nFloat) - v.mkFloat(state.forceFloat(*args[0], pos) - state.forceFloat(*args[1], pos)); + v.mkFloat(state.forceFloat(*args[0], pos, "while evaluating the first argument of the subtraction") + - state.forceFloat(*args[1], pos, "while evaluating the second argument of the subtraction")); else - v.mkInt(state.forceInt(*args[0], pos) - state.forceInt(*args[1], pos)); + v.mkInt( state.forceInt(*args[0], pos, "while evaluating the first argument of the subtraction") + - state.forceInt(*args[1], pos, "while evaluating the second argument of the subtraction")); } static RegisterPrimOp primop_sub({ @@ -3194,14 +3307,16 @@ static RegisterPrimOp primop_sub({ .fun = prim_sub, }); -static void prim_mul(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_mul(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); state.forceValue(*args[1], pos); if (args[0]->type() == nFloat || args[1]->type() == nFloat) - v.mkFloat(state.forceFloat(*args[0], pos) * state.forceFloat(*args[1], pos)); + v.mkFloat(state.forceFloat(*args[0], pos, "while evaluating the first of the multiplication") + * state.forceFloat(*args[1], pos, "while evaluating the second argument of the multiplication")); else - v.mkInt(state.forceInt(*args[0], pos) * state.forceInt(*args[1], pos)); + v.mkInt( state.forceInt(*args[0], pos, "while evaluating the first argument of the multiplication") + * state.forceInt(*args[1], pos, "while evaluating the second argument of the multiplication")); } static RegisterPrimOp primop_mul({ @@ -3213,29 +3328,29 @@ static RegisterPrimOp primop_mul({ .fun = prim_mul, }); -static void prim_div(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_div(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); state.forceValue(*args[1], pos); - NixFloat f2 = state.forceFloat(*args[1], pos); + NixFloat f2 = state.forceFloat(*args[1], pos, "while evaluating the second operand of the division"); if (f2 == 0) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("division by zero"), - .errPos = pos - }); + .errPos = state.positions[pos] + })); if (args[0]->type() == nFloat || args[1]->type() == nFloat) { - v.mkFloat(state.forceFloat(*args[0], pos) / state.forceFloat(*args[1], pos)); + v.mkFloat(state.forceFloat(*args[0], pos, "while evaluating the first operand of the division") / f2); } else { - NixInt i1 = state.forceInt(*args[0], pos); - NixInt i2 = state.forceInt(*args[1], pos); + NixInt i1 = state.forceInt(*args[0], pos, "while evaluating the first operand of the division"); + NixInt i2 = state.forceInt(*args[1], pos, "while evaluating the second operand of the division"); /* Avoid division overflow as it might raise SIGFPE. */ if (i1 == std::numeric_limits<NixInt>::min() && i2 == -1) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("overflow in integer division"), - .errPos = pos - }); + .errPos = state.positions[pos] + })); v.mkInt(i1 / i2); } @@ -3250,9 +3365,10 @@ static RegisterPrimOp primop_div({ .fun = prim_div, }); -static void prim_bitAnd(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_bitAnd(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - v.mkInt(state.forceInt(*args[0], pos) & state.forceInt(*args[1], pos)); + v.mkInt(state.forceInt(*args[0], pos, "while evaluating the first argument passed to builtins.bitAnd") + & state.forceInt(*args[1], pos, "while evaluating the second argument passed to builtins.bitAnd")); } static RegisterPrimOp primop_bitAnd({ @@ -3264,9 +3380,10 @@ static RegisterPrimOp primop_bitAnd({ .fun = prim_bitAnd, }); -static void prim_bitOr(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_bitOr(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - v.mkInt(state.forceInt(*args[0], pos) | state.forceInt(*args[1], pos)); + v.mkInt(state.forceInt(*args[0], pos, "while evaluating the first argument passed to builtins.bitOr") + | state.forceInt(*args[1], pos, "while evaluating the second argument passed to builtins.bitOr")); } static RegisterPrimOp primop_bitOr({ @@ -3278,9 +3395,10 @@ static RegisterPrimOp primop_bitOr({ .fun = prim_bitOr, }); -static void prim_bitXor(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_bitXor(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - v.mkInt(state.forceInt(*args[0], pos) ^ state.forceInt(*args[1], pos)); + v.mkInt(state.forceInt(*args[0], pos, "while evaluating the first argument passed to builtins.bitXor") + ^ state.forceInt(*args[1], pos, "while evaluating the second argument passed to builtins.bitXor")); } static RegisterPrimOp primop_bitXor({ @@ -3292,11 +3410,12 @@ static RegisterPrimOp primop_bitXor({ .fun = prim_bitXor, }); -static void prim_lessThan(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_lessThan(EvalState & state, const PosIdx pos, Value * * args, Value & v) { state.forceValue(*args[0], pos); state.forceValue(*args[1], pos); - CompareValues comp{state}; + // pos is exact here, no need for a message. + CompareValues comp(state, pos, ""); v.mkBool(comp(args[0], args[1])); } @@ -3320,10 +3439,10 @@ static RegisterPrimOp primop_lessThan({ /* Convert the argument to a string. Paths are *not* copied to the store, so `toString /foo/bar' yields `"/foo/bar"', not `"/nix/store/whatever..."'. */ -static void prim_toString(EvalState & state, const Pos & pos, Value * * args, Value & v) +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); + auto s = state.coerceToString(pos, *args[0], context, true, false, "while evaluating the first argument passed to builtins.toString"); v.mkString(*s, context); } @@ -3355,18 +3474,18 @@ static RegisterPrimOp primop_toString({ at character position `min(start, stringLength str)' inclusive and ending at `min(start + len, stringLength str)'. `start' must be non-negative. */ -static void prim_substring(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_substring(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - int start = state.forceInt(*args[0], pos); - int len = state.forceInt(*args[1], pos); + int start = state.forceInt(*args[0], pos, "while evaluating the first argument (the start offset) passed to builtins.substring"); + int len = state.forceInt(*args[1], pos, "while evaluating the second argument (the substring length) passed to builtins.substring"); PathSet context; - auto s = state.coerceToString(pos, *args[2], context); + auto s = state.coerceToString(pos, *args[2], context, "while evaluating the third argument (the string) passed to builtins.substring"); if (start < 0) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("negative start position in 'substring'"), - .errPos = pos - }); + .errPos = state.positions[pos] + })); v.mkString((unsigned int) start >= s->size() ? "" : s->substr(start, len), context); } @@ -3391,10 +3510,10 @@ static RegisterPrimOp primop_substring({ .fun = prim_substring, }); -static void prim_stringLength(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_stringLength(EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - auto s = state.coerceToString(pos, *args[0], context); + auto s = state.coerceToString(pos, *args[0], context, "while evaluating the argument passed to builtins.stringLength"); v.mkInt(s->size()); } @@ -3409,18 +3528,18 @@ static RegisterPrimOp primop_stringLength({ }); /* Return the cryptographic hash of a string in base-16. */ -static void prim_hashString(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_hashString(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto type = state.forceStringNoCtx(*args[0], pos); + auto type = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.hashString"); std::optional<HashType> ht = parseHashType(type); if (!ht) - throw Error({ + state.debugThrowLastTrace(Error({ .msg = hintfmt("unknown hash type '%1%'", type), - .errPos = pos - }); + .errPos = state.positions[pos] + })); PathSet context; // discarded - auto s = state.forceString(*args[1], context, pos); + auto s = state.forceString(*args[1], context, pos, "while evaluating the second argument passed to builtins.hashString"); v.mkString(hashString(*ht, s).to_string(Base16, false)); } @@ -3457,16 +3576,16 @@ std::shared_ptr<RegexCache> makeRegexCache() return std::make_shared<RegexCache>(); } -void prim_match(EvalState & state, const Pos & pos, Value * * args, Value & v) +void prim_match(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto re = state.forceStringNoCtx(*args[0], pos); + auto re = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.match"); try { auto regex = state.regexCache->get(re); PathSet context; - const auto str = state.forceString(*args[1], context, pos); + const auto str = state.forceString(*args[1], context, pos, "while evaluating the second argument passed to builtins.match"); std::cmatch match; if (!std::regex_match(str.begin(), str.end(), match, regex)) { @@ -3484,19 +3603,18 @@ void prim_match(EvalState & state, const Pos & pos, Value * * args, Value & v) (v.listElems()[i] = state.allocValue())->mkString(match[i + 1].str()); } - } catch (std::regex_error &e) { + } catch (std::regex_error & e) { if (e.code() == std::regex_constants::error_space) { // limit is _GLIBCXX_REGEX_STATE_LIMIT for libstdc++ - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("memory limit exceeded by regular expression '%s'", re), - .errPos = pos - }); - } else { - throw EvalError({ + .errPos = state.positions[pos] + })); + } else + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("invalid regular expression '%s'", re), - .errPos = pos - }); - } + .errPos = state.positions[pos] + })); } } @@ -3531,23 +3649,23 @@ static RegisterPrimOp primop_match({ builtins.match "[[:space:]]+([[:upper:]]+)[[:space:]]+" " FOO " ``` - Evaluates to `[ "foo" ]`. + Evaluates to `[ "FOO" ]`. )s", .fun = prim_match, }); /* Split a string with a regular expression, and return a list of the non-matching parts interleaved by the lists of the matching groups. */ -void prim_split(EvalState & state, const Pos & pos, Value * * args, Value & v) +void prim_split(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto re = state.forceStringNoCtx(*args[0], pos); + auto re = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.split"); try { auto regex = state.regexCache->get(re); PathSet context; - const auto str = state.forceString(*args[1], context, pos); + const auto str = state.forceString(*args[1], context, pos, "while evaluating the second argument passed to builtins.split"); auto begin = std::cregex_iterator(str.begin(), str.end(), regex); auto end = std::cregex_iterator(); @@ -3589,19 +3707,18 @@ void prim_split(EvalState & state, const Pos & pos, Value * * args, Value & v) assert(idx == 2 * len + 1); - } catch (std::regex_error &e) { + } catch (std::regex_error & e) { if (e.code() == std::regex_constants::error_space) { // limit is _GLIBCXX_REGEX_STATE_LIMIT for libstdc++ - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("memory limit exceeded by regular expression '%s'", re), - .errPos = pos - }); - } else { - throw EvalError({ + .errPos = state.positions[pos] + })); + } else + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("invalid regular expression '%s'", re), - .errPos = pos - }); - } + .errPos = state.positions[pos] + })); } } @@ -3634,7 +3751,7 @@ static RegisterPrimOp primop_split({ Evaluates to `[ "" [ "a" null ] "b" [ null "c" ] "" ]`. ```nix - builtins.split "([[:upper:]]+)" " FOO " + builtins.split "([[:upper:]]+)" " FOO " ``` Evaluates to `[ " " [ "FOO" ] " " ]`. @@ -3642,12 +3759,12 @@ static RegisterPrimOp primop_split({ .fun = prim_split, }); -static void prim_concatStringsSep(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_concatStringsSep(EvalState & state, const PosIdx pos, Value * * args, Value & v) { PathSet context; - auto sep = state.forceString(*args[0], context, pos); - state.forceList(*args[1], pos); + auto sep = state.forceString(*args[0], context, pos, "while evaluating the first argument (the separator string) passed to builtins.concatStringsSep"); + state.forceList(*args[1], pos, "while evaluating the second argument (the list of strings to concat) passed to builtins.concatStringsSep"); std::string res; res.reserve((args[1]->listSize() + 32) * sep.size()); @@ -3655,7 +3772,7 @@ static void prim_concatStringsSep(EvalState & state, const Pos & pos, Value * * for (auto elem : args[1]->listItems()) { if (first) first = false; else res += sep; - res += *state.coerceToString(pos, *elem, context); + res += *state.coerceToString(pos, *elem, context, "while evaluating one element of the list of strings to concat passed to builtins.concatStringsSep"); } v.mkString(res, context); @@ -3672,31 +3789,31 @@ static RegisterPrimOp primop_concatStringsSep({ .fun = prim_concatStringsSep, }); -static void prim_replaceStrings(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_replaceStrings(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - state.forceList(*args[0], pos); - state.forceList(*args[1], pos); + 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()) - throw EvalError({ + state.debugThrowLastTrace(EvalError({ .msg = hintfmt("'from' and 'to' arguments to 'replaceStrings' have different lengths"), - .errPos = pos - }); + .errPos = state.positions[pos] + })); std::vector<std::string> from; from.reserve(args[0]->listSize()); for (auto elem : args[0]->listItems()) - from.emplace_back(state.forceString(*elem, pos)); + from.emplace_back(state.forceString(*elem, pos, "while evaluating one of the strings to replace in 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); + auto s = state.forceString(*elem, ctx, pos, "while evaluating one of the replacement strings of builtins.replaceStrings"); to.emplace_back(s, std::move(ctx)); } PathSet context; - auto s = state.forceString(*args[2], context, pos); + auto s = state.forceString(*args[2], context, pos, "while evaluating the third argument passed to builtins.replaceStrings"); std::string res; // Loops one past last character to handle the case where 'from' contains an empty string. @@ -3752,9 +3869,9 @@ static RegisterPrimOp primop_replaceStrings({ *************************************************************/ -static void prim_parseDrvName(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_parseDrvName(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto name = state.forceStringNoCtx(*args[0], pos); + auto name = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.parseDrvName"); DrvName parsed(name); auto attrs = state.buildBindings(2); attrs.alloc(state.sName).mkString(parsed.name); @@ -3767,8 +3884,8 @@ static RegisterPrimOp primop_parseDrvName({ .args = {"s"}, .doc = R"( Split the string *s* into a package name and version. The package - name is everything up to but not including the first dash followed - by a digit, and the version is everything following that dash. The + name is everything up to but not including the first dash not followed + by a letter, and the version is everything following that dash. The result is returned in a set `{ name, version }`. Thus, `builtins.parseDrvName "nix-0.12pre12876"` returns `{ name = "nix"; version = "0.12pre12876"; }`. @@ -3776,10 +3893,10 @@ static RegisterPrimOp primop_parseDrvName({ .fun = prim_parseDrvName, }); -static void prim_compareVersions(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_compareVersions(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto version1 = state.forceStringNoCtx(*args[0], pos); - auto version2 = state.forceStringNoCtx(*args[1], pos); + auto version1 = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.compareVersions"); + auto version2 = state.forceStringNoCtx(*args[1], pos, "while evaluating the second argument passed to builtins.compareVersions"); v.mkInt(compareVersions(version1, version2)); } @@ -3796,9 +3913,9 @@ static RegisterPrimOp primop_compareVersions({ .fun = prim_compareVersions, }); -static void prim_splitVersion(EvalState & state, const Pos & pos, Value * * args, Value & v) +static void prim_splitVersion(EvalState & state, const PosIdx pos, Value * * args, Value & v) { - auto version = state.forceStringNoCtx(*args[0], pos); + auto version = state.forceStringNoCtx(*args[0], pos, "while evaluating the first argument passed to builtins.splitVersion"); auto iter = version.cbegin(); Strings components; while (iter != version.cend()) { @@ -3898,6 +4015,18 @@ void EvalState::createBaseEnv() addPrimOp("__exec", 1, prim_exec); } + addPrimOp({ + .fun = evalSettings.traceVerbose ? prim_trace : prim_second, + .arity = 2, + .name = "__traceVerbose", + .args = { "e1", "e2" }, + .doc = R"( + Evaluate *e1* and print its abstract syntax representation on standard + error if `--trace-verbose` is enabled. Then return *e2*. This function + is useful for debugging. + )", + }); + /* Add a value containing the current Nix expression search path. */ mkList(v, searchPath.size()); int n = 0; @@ -3917,7 +4046,7 @@ void EvalState::createBaseEnv() addPrimOp({ .fun = primOp.fun, .arity = std::max(primOp.args.size(), primOp.arity), - .name = symbols.create(primOp.name), + .name = primOp.name, .args = primOp.args, .doc = primOp.doc, }); @@ -3925,7 +4054,7 @@ void EvalState::createBaseEnv() /* Add a wrapper around the derivation primop that computes the `drvPath' and `outPath' attributes lazily. */ - sDerivationNix = symbols.create("//builtin/derivation.nix"); + sDerivationNix = symbols.create(derivationNixPath); auto vDerivation = allocValue(); addConstant("derivation", vDerivation); @@ -3933,7 +4062,7 @@ void EvalState::createBaseEnv() because attribute lookups expect it to be sorted. */ baseEnv.values[0]->attrs->sort(); - staticBaseEnv.sort(); + staticBaseEnv->sort(); /* Note: we have to initialize the 'derivation' constant *after* building baseEnv/staticBaseEnv because it uses 'builtins'. */ @@ -3942,7 +4071,7 @@ void EvalState::createBaseEnv() // the parser needs two NUL bytes as terminators; one of them // is implied by being a C string. "\0"; - eval(parse(code, sizeof(code), foFile, sDerivationNix, "/", staticBaseEnv), *vDerivation); + eval(parse(code, sizeof(code), derivationNixPath, "/", staticBaseEnv), *vDerivation); } |