diff options
Diffstat (limited to 'src/libexpr/parser/parser.cc')
| -rw-r--r-- | src/libexpr/parser/parser.cc | 868 |
1 files changed, 11 insertions, 857 deletions
diff --git a/src/libexpr/parser/parser.cc b/src/libexpr/parser/parser.cc index 17463056c..896a54981 100644 --- a/src/libexpr/parser/parser.cc +++ b/src/libexpr/parser/parser.cc @@ -14,857 +14,11 @@ #include <charconv> #include <memory> -// flip this define when doing parser development to enable some g checks. -#if 0 -#include <tao/pegtl/contrib/analyze.hpp> -#define ANALYZE_GRAMMAR \ - ([] { \ - const std::size_t issues = tao::pegtl::analyze<grammar::root>(); \ - assert(issues == 0); \ - })() -#else -#define ANALYZE_GRAMMAR ((void) 0) -#endif - -namespace p = tao::pegtl; - -namespace nix::parser { -namespace { - -template<typename> -inline constexpr const char * error_message = nullptr; - -#define error_message_for(...) \ - template<> inline constexpr auto error_message<__VA_ARGS__> - -error_message_for(p::one<'{'>) = "expecting '{'"; -error_message_for(p::one<'}'>) = "expecting '}'"; -error_message_for(p::one<'"'>) = "expecting '\"'"; -error_message_for(p::one<';'>) = "expecting ';'"; -error_message_for(p::one<')'>) = "expecting ')'"; -error_message_for(p::one<']'>) = "expecting ']'"; -error_message_for(p::one<':'>) = "expecting ':'"; -error_message_for(p::string<'\'', '\''>) = "expecting \"''\""; -error_message_for(p::any) = "expecting any character"; -error_message_for(grammar::eof) = "expecting end of file"; -error_message_for(grammar::seps) = "expecting separators"; -error_message_for(grammar::path::forbid_prefix_triple_slash) = "too many slashes in path"; -error_message_for(grammar::path::forbid_prefix_double_slash_no_interp) = "path has a trailing slash"; -error_message_for(grammar::expr) = "expecting expression"; -error_message_for(grammar::expr::unary) = "expecting expression"; -error_message_for(grammar::binding::equal) = "expecting '='"; -error_message_for(grammar::expr::lambda::arg) = "expecting identifier"; -error_message_for(grammar::formals) = "expecting formals"; -error_message_for(grammar::attrpath) = "expecting attribute path"; -error_message_for(grammar::expr::select) = "expecting selection expression"; -error_message_for(grammar::t::kw_then) = "expecting 'then'"; -error_message_for(grammar::t::kw_else) = "expecting 'else'"; -error_message_for(grammar::t::kw_in) = "expecting 'in'"; - -struct SyntaxErrors -{ - template<typename Rule> - static constexpr auto message = error_message<Rule>; - - template<typename Rule> - static constexpr bool raise_on_failure = false; -}; - -template<typename Rule> -struct Control : p::must_if<SyntaxErrors>::control<Rule> -{ - template<typename ParseInput, typename... States> - [[noreturn]] static void raise(const ParseInput & in, States &&... st) - { - if (in.empty()) { - std::string expected; - if constexpr (constexpr auto msg = error_message<Rule>) - expected = fmt(", %s", msg); - throw p::parse_error("unexpected end of file" + expected, in); - } - p::must_if<SyntaxErrors>::control<Rule>::raise(in, st...); - } -}; - -struct ExprState - : grammar:: - operator_semantics<ExprState, PosIdx, AttrPath, std::pair<PosIdx, std::unique_ptr<Expr>>> -{ - std::unique_ptr<Expr> popExprOnly() { - return std::move(popExpr().second); - } - - template<typename Op, typename... Args> - std::unique_ptr<Expr> applyUnary(Args &&... args) { - return std::make_unique<Op>(popExprOnly(), std::forward<Args>(args)...); - } - - template<typename Op> - std::unique_ptr<Expr> applyBinary(PosIdx pos) { - auto right = popExprOnly(), left = popExprOnly(); - return std::make_unique<Op>(pos, std::move(left), std::move(right)); - } - - std::unique_ptr<Expr> call(PosIdx pos, Symbol fn, bool flip = false) - { - std::vector<std::unique_ptr<Expr>> args(2); - args[flip ? 0 : 1] = popExprOnly(); - args[flip ? 1 : 0] = popExprOnly(); - return std::make_unique<ExprCall>(pos, std::make_unique<ExprVar>(fn), std::move(args)); - } - - std::unique_ptr<Expr> pipe(PosIdx pos, State & state, bool flip = false) - { - if (!state.featureSettings.isEnabled(Xp::PipeOperator)) - throw ParseError({ - .msg = HintFmt("Pipe operator is disabled"), - .pos = state.positions[pos] - }); - - // Reverse the order compared to normal function application: arg |> fn - std::unique_ptr<Expr> fn, arg; - if (flip) { - fn = popExprOnly(); - arg = popExprOnly(); - } else { - arg = popExprOnly(); - fn = popExprOnly(); - } - std::vector<std::unique_ptr<Expr>> args{1}; - args[0] = std::move(arg); - - return std::make_unique<ExprCall>(pos, std::move(fn), std::move(args)); - } - - std::unique_ptr<Expr> order(PosIdx pos, bool less, State & state) - { - return call(pos, state.s.lessThan, !less); - } - - std::unique_ptr<Expr> concatStrings(PosIdx pos) - { - std::vector<std::pair<PosIdx, std::unique_ptr<Expr>>> args(2); - args[1] = popExpr(); - args[0] = popExpr(); - return std::make_unique<ExprConcatStrings>(pos, false, std::move(args)); - } - - std::unique_ptr<Expr> negate(PosIdx pos, State & state) - { - std::vector<std::unique_ptr<Expr>> args(2); - args[0] = std::make_unique<ExprInt>(0); - args[1] = popExprOnly(); - return std::make_unique<ExprCall>(pos, std::make_unique<ExprVar>(state.s.sub), std::move(args)); - } - - std::pair<PosIdx, std::unique_ptr<Expr>> applyOp(PosIdx pos, auto & op, State & state) { - using Op = grammar::op; - - auto not_ = [] (auto e) { - return std::make_unique<ExprOpNot>(std::move(e)); - }; - - return { - pos, - (overloaded { - [&] (Op::implies) { return applyBinary<ExprOpImpl>(pos); }, - [&] (Op::or_) { return applyBinary<ExprOpOr>(pos); }, - [&] (Op::and_) { return applyBinary<ExprOpAnd>(pos); }, - [&] (Op::equals) { return applyBinary<ExprOpEq>(pos); }, - [&] (Op::not_equals) { return applyBinary<ExprOpNEq>(pos); }, - [&] (Op::less) { return order(pos, true, state); }, - [&] (Op::greater_eq) { return not_(order(pos, true, state)); }, - [&] (Op::greater) { return order(pos, false, state); }, - [&] (Op::less_eq) { return not_(order(pos, false, state)); }, - [&] (Op::update) { return applyBinary<ExprOpUpdate>(pos); }, - [&] (Op::not_) { return applyUnary<ExprOpNot>(); }, - [&] (Op::plus) { return concatStrings(pos); }, - [&] (Op::minus) { return call(pos, state.s.sub); }, - [&] (Op::mul) { return call(pos, state.s.mul); }, - [&] (Op::div) { return call(pos, state.s.div); }, - [&] (Op::concat) { return applyBinary<ExprOpConcatLists>(pos); }, - [&] (has_attr & a) { return applyUnary<ExprOpHasAttr>(std::move(a.path)); }, - [&] (Op::unary_minus) { return negate(pos, state); }, - [&] (Op::pipe_right) { return pipe(pos, state, true); }, - [&] (Op::pipe_left) { return pipe(pos, state); }, - })(op) - }; - } - - // always_inline is needed, otherwise pushOp slows down considerably - [[noreturn, gnu::always_inline]] - static void badOperator(PosIdx pos, State & state) - { - throw ParseError({ - .msg = HintFmt("syntax error, unexpected operator"), - .pos = state.positions[pos] - }); - } - - template<typename Expr, typename... Args> - Expr & pushExpr(PosIdx pos, Args && ... args) - { - auto p = std::make_unique<Expr>(std::forward<Args>(args)...); - auto & result = *p; - exprs.emplace_back(pos, std::move(p)); - return result; - } -}; - -struct SubexprState { -private: - ExprState * up; - -public: - explicit SubexprState(ExprState & up, auto &...) : up(&up) {} - operator ExprState &() { return *up; } - ExprState * operator->() { return up; } -}; - - - -template<typename Rule> -struct BuildAST : grammar::nothing<Rule> {}; - -struct LambdaState : SubexprState { - using SubexprState::SubexprState; - - Symbol arg; - std::unique_ptr<Formals> formals; -}; - -struct FormalsState : SubexprState { - using SubexprState::SubexprState; - - Formals formals{}; - Formal formal{}; -}; - -template<> struct BuildAST<grammar::formal::name> { - static void apply(const auto & in, FormalsState & s, State & ps) { - s.formal = { - .pos = ps.at(in), - .name = ps.symbols.create(in.string_view()), - }; - } -}; - -template<> struct BuildAST<grammar::formal> { - static void apply0(FormalsState & s, State &) { - s.formals.formals.emplace_back(std::move(s.formal)); - } -}; - -template<> struct BuildAST<grammar::formal::default_value> { - static void apply0(FormalsState & s, State & ps) { - s.formal.def = s->popExprOnly(); - } -}; - -template<> struct BuildAST<grammar::formals::ellipsis> { - static void apply0(FormalsState & s, State &) { - s.formals.ellipsis = true; - } -}; - -template<> struct BuildAST<grammar::formals> : change_head<FormalsState> { - static void success0(FormalsState & f, LambdaState & s, State &) { - s.formals = std::make_unique<Formals>(std::move(f.formals)); - } -}; - -struct AttrState : SubexprState { - using SubexprState::SubexprState; - - std::vector<AttrName> attrs; - - template <typename T> - void pushAttr(T && attr, PosIdx) { attrs.emplace_back(std::forward<T>(attr)); } -}; - -template<> struct BuildAST<grammar::attr::simple> { - static void apply(const auto & in, auto & s, State & ps) { - s.pushAttr(ps.symbols.create(in.string_view()), ps.at(in)); - } -}; - -template<> struct BuildAST<grammar::attr::string> { - static void apply(const auto & in, auto & s, State & ps) { - auto e = s->popExprOnly(); - if (auto str = dynamic_cast<ExprString *>(e.get())) - s.pushAttr(ps.symbols.create(str->s), ps.at(in)); - else - s.pushAttr(std::move(e), ps.at(in)); - } -}; - -template<> struct BuildAST<grammar::attr::expr> : BuildAST<grammar::attr::string> {}; - -struct BindingsState : SubexprState { - using SubexprState::SubexprState; - - ExprAttrs attrs; - AttrPath path; - std::unique_ptr<Expr> value; -}; - -struct InheritState : SubexprState { - using SubexprState::SubexprState; - - std::vector<std::pair<AttrName, PosIdx>> attrs; - std::unique_ptr<Expr> from; - PosIdx fromPos; - - template <typename T> - void pushAttr(T && attr, PosIdx pos) { attrs.emplace_back(std::forward<T>(attr), pos); } -}; - -template<> struct BuildAST<grammar::inherit::from> { - static void apply(const auto & in, InheritState & s, State & ps) { - s.from = s->popExprOnly(); - s.fromPos = ps.at(in); - } -}; - -template<> struct BuildAST<grammar::inherit> : change_head<InheritState> { - static void success0(InheritState & s, BindingsState & b, State & ps) { - auto & attrs = b.attrs.attrs; - // TODO this should not reuse generic attrpath rules. - for (auto & [i, iPos] : s.attrs) { - if (i.symbol) - continue; - if (auto str = dynamic_cast<ExprString *>(i.expr.get())) - i = AttrName(ps.symbols.create(str->s)); - else { - throw ParseError({ - .msg = HintFmt("dynamic attributes not allowed in inherit"), - .pos = ps.positions[iPos] - }); - } - } - if (s.from != nullptr) { - if (!b.attrs.inheritFromExprs) - b.attrs.inheritFromExprs = std::make_unique<std::vector<ref<Expr>>>(); - auto fromExpr = ref<Expr>(std::move(s.from)); - b.attrs.inheritFromExprs->push_back(fromExpr); - for (auto & [i, iPos] : s.attrs) { - if (attrs.find(i.symbol) != attrs.end()) - ps.dupAttr(i.symbol, iPos, attrs[i.symbol].pos); - auto inheritFrom = std::make_unique<ExprInheritFrom>( - s.fromPos, - b.attrs.inheritFromExprs->size() - 1, - fromExpr - ); - attrs.emplace( - i.symbol, - ExprAttrs::AttrDef( - std::make_unique<ExprSelect>(iPos, std::move(inheritFrom), i.symbol), - iPos, - ExprAttrs::AttrDef::Kind::InheritedFrom)); - } - } else { - for (auto & [i, iPos] : s.attrs) { - if (attrs.find(i.symbol) != attrs.end()) - ps.dupAttr(i.symbol, iPos, attrs[i.symbol].pos); - attrs.emplace( - i.symbol, - ExprAttrs::AttrDef( - std::make_unique<ExprVar>(iPos, i.symbol), - iPos, - ExprAttrs::AttrDef::Kind::Inherited)); - } - } - } -}; - -template<> struct BuildAST<grammar::binding::path> : change_head<AttrState> { - static void success0(AttrState & a, BindingsState & s, State & ps) { - s.path = std::move(a.attrs); - } -}; - -template<> struct BuildAST<grammar::binding::value> { - static void apply0(BindingsState & s, State & ps) { - s.value = s->popExprOnly(); - } -}; - -template<> struct BuildAST<grammar::binding> { - static void apply(const auto & in, BindingsState & s, State & ps) { - ps.addAttr(&s.attrs, std::move(s.path), std::move(s.value), ps.at(in)); - } -}; - -template<> struct BuildAST<grammar::expr::id> { - static void apply(const auto & in, ExprState & s, State & ps) { - if (in.string_view() == "__curPos") - s.pushExpr<ExprPos>(ps.at(in), ps.at(in)); - else - s.pushExpr<ExprVar>(ps.at(in), ps.at(in), ps.symbols.create(in.string_view())); - } -}; - -template<> struct BuildAST<grammar::expr::int_> { - static void apply(const auto & in, ExprState & s, State & ps) { - int64_t v; - if (std::from_chars(in.begin(), in.end(), v).ec != std::errc{}) { - throw ParseError({ - .msg = HintFmt("invalid integer '%1%'", in.string_view()), - .pos = ps.positions[ps.at(in)], - }); - } - s.pushExpr<ExprInt>(noPos, v); - } -}; - -template<> struct BuildAST<grammar::expr::float_> { - static void apply(const auto & in, ExprState & s, State & ps) { - // copy the input into a temporary string so we can call stod. - // can't use from_chars because libc++ (thus darwin) does not have it, - // and floats are not performance-sensitive anyway. if they were you'd - // be in much bigger trouble than this. - // - // we also get to do a locale-save dance because stod is locale-aware and - // something (a plugin?) may have called setlocale or uselocale. - static struct locale_hack { - locale_t posix; - locale_hack(): posix(newlocale(LC_ALL_MASK, "POSIX", 0)) - { - if (posix == 0) - throw SysError("could not get POSIX locale"); - } - } locale; - - auto tmp = in.string(); - double v = [&] { - auto oldLocale = uselocale(locale.posix); - Finally resetLocale([=] { uselocale(oldLocale); }); - try { - return std::stod(tmp); - } catch (...) { - throw ParseError({ - .msg = HintFmt("invalid float '%1%'", in.string_view()), - .pos = ps.positions[ps.at(in)], - }); - } - }(); - s.pushExpr<ExprFloat>(noPos, v); - } -}; - -struct StringState : SubexprState { - using SubexprState::SubexprState; - - std::string currentLiteral; - PosIdx currentPos; - std::vector<std::pair<nix::PosIdx, std::unique_ptr<Expr>>> parts; - - void append(PosIdx pos, std::string_view s) - { - if (currentLiteral.empty()) - currentPos = pos; - currentLiteral += s; - } - - // FIXME this truncates strings on NUL for compat with the old parser. ideally - // we should use the decomposition the g gives us instead of iterating over - // the entire string again. - static void unescapeStr(std::string & str) - { - char * s = str.data(); - char * t = s; - char c; - while ((c = *s++)) { - if (c == '\\') { - c = *s++; - if (c == 'n') *t = '\n'; - else if (c == 'r') *t = '\r'; - else if (c == 't') *t = '\t'; - else *t = c; - } - else if (c == '\r') { - /* Normalise CR and CR/LF into LF. */ - *t = '\n'; - if (*s == '\n') s++; /* cr/lf */ - } - else *t = c; - t++; - } - str.resize(t - str.data()); - } - - void endLiteral() - { - if (!currentLiteral.empty()) { - unescapeStr(currentLiteral); - parts.emplace_back(currentPos, std::make_unique<ExprString>(std::move(currentLiteral))); - } - } - - std::unique_ptr<Expr> finish() - { - if (parts.empty()) { - unescapeStr(currentLiteral); - return std::make_unique<ExprString>(std::move(currentLiteral)); - } else { - endLiteral(); - auto pos = parts[0].first; - return std::make_unique<ExprConcatStrings>(pos, true, std::move(parts)); - } - } -}; - -template<typename... Content> struct BuildAST<grammar::string::literal<Content...>> { - static void apply(const auto & in, StringState & s, State & ps) { - s.append(ps.at(in), in.string_view()); - } -}; - -template<> struct BuildAST<grammar::string::cr_lf> { - static void apply(const auto & in, StringState & s, State & ps) { - s.append(ps.at(in), in.string_view()); // FIXME compat with old parser - } -}; - -template<> struct BuildAST<grammar::string::interpolation> { - static void apply(const auto & in, StringState & s, State & ps) { - s.endLiteral(); - s.parts.emplace_back(ps.at(in), s->popExprOnly()); - } -}; - -template<> struct BuildAST<grammar::string::escape> { - static void apply(const auto & in, StringState & s, State & ps) { - s.append(ps.at(in), "\\"); // FIXME compat with old parser - s.append(ps.at(in), in.string_view()); - } -}; - -template<> struct BuildAST<grammar::string> : change_head<StringState> { - static void success0(StringState & s, ExprState & e, State &) { - e.exprs.emplace_back(noPos, s.finish()); - } -}; - -struct IndStringState : SubexprState { - using SubexprState::SubexprState; - - std::vector<std::pair<PosIdx, std::variant<std::unique_ptr<Expr>, StringToken>>> parts; -}; - -template<bool Indented, typename... Content> -struct BuildAST<grammar::ind_string::literal<Indented, Content...>> { - static void apply(const auto & in, IndStringState & s, State & ps) { - s.parts.emplace_back(ps.at(in), StringToken{in.string_view(), Indented}); - } -}; - -template<> struct BuildAST<grammar::ind_string::interpolation> { - static void apply(const auto & in, IndStringState & s, State & ps) { - s.parts.emplace_back(ps.at(in), s->popExprOnly()); - } -}; - -template<> struct BuildAST<grammar::ind_string::escape> { - static void apply(const auto & in, IndStringState & s, State & ps) { - switch (*in.begin()) { - case 'n': s.parts.emplace_back(ps.at(in), StringToken{"\n"}); break; - case 'r': s.parts.emplace_back(ps.at(in), StringToken{"\r"}); break; - case 't': s.parts.emplace_back(ps.at(in), StringToken{"\t"}); break; - default: s.parts.emplace_back(ps.at(in), StringToken{in.string_view()}); break; - } - } -}; - -template<> struct BuildAST<grammar::ind_string> : change_head<IndStringState> { - static void success(const auto & in, IndStringState & s, ExprState & e, State & ps) { - e.exprs.emplace_back(noPos, ps.stripIndentation(ps.at(in), std::move(s.parts))); - } -}; - -template<typename... Content> struct BuildAST<grammar::path::literal<Content...>> { - static void apply(const auto & in, StringState & s, State & ps) { - s.append(ps.at(in), in.string_view()); - s.endLiteral(); - } -}; - -template<> struct BuildAST<grammar::path::interpolation> : BuildAST<grammar::string::interpolation> {}; - -template<> struct BuildAST<grammar::path::anchor> { - static void apply(const auto & in, StringState & s, State & ps) { - Path path(absPath(in.string(), ps.basePath.path.abs())); - /* add back in the trailing '/' to the first segment */ - if (in.string_view().ends_with('/') && in.size() > 1) - path += "/"; - s.parts.emplace_back(ps.at(in), new ExprPath(std::move(path))); - } -}; - -template<> struct BuildAST<grammar::path::home_anchor> { - static void apply(const auto & in, StringState & s, State & ps) { - if (evalSettings.pureEval) - throw Error("the path '%s' can not be resolved in pure mode", in.string_view()); - Path path(getHome() + in.string_view().substr(1)); - s.parts.emplace_back(ps.at(in), new ExprPath(std::move(path))); - } -}; - -template<> struct BuildAST<grammar::path::searched_path> { - static void apply(const auto & in, StringState & s, State & ps) { - std::vector<std::unique_ptr<Expr>> args{2}; - args[0] = std::make_unique<ExprVar>(ps.s.nixPath); - args[1] = std::make_unique<ExprString>(in.string()); - s.parts.emplace_back( - ps.at(in), - std::make_unique<ExprCall>( - ps.at(in), - std::make_unique<ExprVar>(ps.s.findFile), - std::move(args))); - } -}; - -template<> struct BuildAST<grammar::path> : change_head<StringState> { - template<typename E> - static void check_slash(PosIdx end, StringState & s, State & ps) { - auto e = dynamic_cast<E *>(s.parts.back().second.get()); - if (!e || !e->s.ends_with('/')) - return; - if (s.parts.size() > 1 || e->s != "/") - throw ParseError({ - .msg = HintFmt("path has a trailing slash"), - .pos = ps.positions[end], - }); - } - - static void success(const auto & in, StringState & s, ExprState & e, State & ps) { - s.endLiteral(); - check_slash<ExprPath>(ps.atEnd(in), s, ps); - check_slash<ExprString>(ps.atEnd(in), s, ps); - if (s.parts.size() == 1) { - e.exprs.emplace_back(noPos, std::move(s.parts.back().second)); - } else { - e.pushExpr<ExprConcatStrings>(ps.at(in), ps.at(in), false, std::move(s.parts)); - } - } -}; - -// strings and paths sare handled fully by the grammar-level rule for now -template<> struct BuildAST<grammar::expr::string> : p::maybe_nothing {}; -template<> struct BuildAST<grammar::expr::ind_string> : p::maybe_nothing {}; -template<> struct BuildAST<grammar::expr::path> : p::maybe_nothing {}; - -template<> struct BuildAST<grammar::expr::uri> { - static void apply(const auto & in, ExprState & s, State & ps) { - bool URLLiterals = ps.featureSettings.isEnabled(Dep::UrlLiterals); - if (!URLLiterals) - throw ParseError({ - .msg = HintFmt("URL literals are deprecated, allow using them with --extra-deprecated-features=url-literals"), - .pos = ps.positions[ps.at(in)] - }); - s.pushExpr<ExprString>(ps.at(in), in.string()); - } -}; - -template<> struct BuildAST<grammar::expr::ancient_let> : change_head<BindingsState> { - static void success(const auto & in, BindingsState & b, ExprState & s, State & ps) { - // Added 2024-09-18. Turn into an error at some point in the future. - // See the documentation on deprecated features for more details. - if (!ps.featureSettings.isEnabled(Dep::AncientLet)) - warn( - "%s found at %s. This feature is deprecated and will be removed in the future. Use %s to silence this warning.", - "let {", - ps.positions[ps.at(in)], - "--extra-deprecated-features ancient-let" - ); - - b.attrs.pos = ps.at(in); - b.attrs.recursive = true; - s.pushExpr<ExprSelect>(b.attrs.pos, b.attrs.pos, std::make_unique<ExprAttrs>(std::move(b.attrs)), ps.s.body); - } -}; - -template<> struct BuildAST<grammar::expr::rec_set> : change_head<BindingsState> { - static void success(const auto & in, BindingsState & b, ExprState & s, State & ps) { - // Before inserting new attrs, check for __override and throw an error - // (the error will initially be a warning to ease migration) - if (!featureSettings.isEnabled(Dep::RecSetOverrides) && b.attrs.attrs.contains(ps.s.overrides)) { - ps.overridesFound(ps.at(in)); - } - - b.attrs.pos = ps.at(in); - b.attrs.recursive = true; - s.pushExpr<ExprAttrs>(b.attrs.pos, std::move(b.attrs)); - } -}; - -template<> struct BuildAST<grammar::expr::set> : change_head<BindingsState> { - static void success(const auto & in, BindingsState & b, ExprState & s, State & ps) { - b.attrs.pos = ps.at(in); - s.pushExpr<ExprAttrs>(b.attrs.pos, std::move(b.attrs)); - } -}; - -using ListState = std::vector<std::unique_ptr<Expr>>; - -template<> struct BuildAST<grammar::expr::list> : change_head<ListState> { - static void success(const auto & in, ListState & ls, ExprState & s, State & ps) { - auto e = std::make_unique<ExprList>(); - e->elems = std::move(ls); - s.exprs.emplace_back(ps.at(in), std::move(e)); - } -}; - -template<> struct BuildAST<grammar::expr::list::entry> : change_head<ExprState> { - static void success0(ExprState & e, ListState & s, State & ps) { - s.emplace_back(e.finish(ps).second); - } -}; - -struct SelectState : SubexprState { - using SubexprState::SubexprState; - - PosIdx pos; - ExprSelect * e = nullptr; -}; - -template<> struct BuildAST<grammar::expr::select::head> { - static void apply(const auto & in, SelectState & s, State & ps) { - s.pos = ps.at(in); - } -}; - -template<> struct BuildAST<grammar::expr::select::attr> : change_head<AttrState> { - static void success0(AttrState & a, SelectState & s, State &) { - s.e = &s->pushExpr<ExprSelect>(s.pos, s.pos, s->popExprOnly(), std::move(a.attrs), nullptr); - } -}; - -template<> struct BuildAST<grammar::expr::select::attr_or> { - static void apply0(SelectState & s, State &) { - s.e->def = s->popExprOnly(); - } -}; - -template<> struct BuildAST<grammar::expr::select::as_app_or> { - static void apply(const auto & in, SelectState & s, State & ps) { - std::vector<std::unique_ptr<Expr>> args(1); - args[0] = std::make_unique<ExprVar>(ps.at(in), ps.s.or_); - s->pushExpr<ExprCall>(s.pos, s.pos, s->popExprOnly(), std::move(args)); - } -}; - -template<> struct BuildAST<grammar::expr::select> : change_head<SelectState> { - static void success0(const auto &...) {} -}; - -struct AppState : SubexprState { - using SubexprState::SubexprState; - - PosIdx pos; - ExprCall * e = nullptr; -}; - -template<> struct BuildAST<grammar::expr::app::select_or_fn> { - static void apply(const auto & in, AppState & s, State & ps) { - s.pos = ps.at(in); - } -}; - -template<> struct BuildAST<grammar::expr::app::first_arg> { - static void apply(auto & in, AppState & s, State & ps) { - auto arg = s->popExprOnly(), fn = s->popExprOnly(); - if ((s.e = dynamic_cast<ExprCall *>(fn.get()))) { - // TODO remove. - // AST compat with old parser, semantics are the same. - // this can happen on occasions such as `<p> <p>` or `a or b or`, - // neither of which are super worth optimizing. - s.e->args.push_back(std::move(arg)); - s->exprs.emplace_back(noPos, std::move(fn)); - } else { - std::vector<std::unique_ptr<Expr>> args{1}; - args[0] = std::move(arg); - s.e = &s->pushExpr<ExprCall>(s.pos, s.pos, std::move(fn), std::move(args)); - } - } -}; - -template<> struct BuildAST<grammar::expr::app::another_arg> { - static void apply0(AppState & s, State & ps) { - s.e->args.push_back(s->popExprOnly()); - } -}; - -template<> struct BuildAST<grammar::expr::app> : change_head<AppState> { - static void success0(const auto &...) {} -}; - -template<typename Op> struct BuildAST<grammar::expr::operator_<Op>> { - static void apply(const auto & in, ExprState & s, State & ps) { - s.pushOp(ps.at(in), Op{}, ps); - } -}; -template<> struct BuildAST<grammar::expr::operator_<grammar::op::has_attr>> : change_head<AttrState> { - static void success(const auto & in, AttrState & a, ExprState & s, State & ps) { - s.pushOp(ps.at(in), ExprState::has_attr{{}, std::move(a.attrs)}, ps); - } -}; - -template<> struct BuildAST<grammar::expr::lambda::arg> { - static void apply(const auto & in, LambdaState & s, State & ps) { - s.arg = ps.symbols.create(in.string_view()); - } -}; - -template<> struct BuildAST<grammar::expr::lambda> : change_head<LambdaState> { - static void success(const auto & in, LambdaState & l, ExprState & s, State & ps) { - if (l.formals) - l.formals = ps.validateFormals(std::move(l.formals), ps.at(in), l.arg); - s.pushExpr<ExprLambda>(ps.at(in), ps.at(in), l.arg, std::move(l.formals), l->popExprOnly()); - } -}; - -template<> struct BuildAST<grammar::expr::assert_> { - static void apply(const auto & in, ExprState & s, State & ps) { - auto body = s.popExprOnly(), cond = s.popExprOnly(); - s.pushExpr<ExprAssert>(ps.at(in), ps.at(in), std::move(cond), std::move(body)); - } -}; - -template<> struct BuildAST<grammar::expr::with> { - static void apply(const auto & in, ExprState & s, State & ps) { - auto body = s.popExprOnly(), scope = s.popExprOnly(); - s.pushExpr<ExprWith>(ps.at(in), ps.at(in), std::move(scope), std::move(body)); - } -}; - -template<> struct BuildAST<grammar::expr::let> : change_head<BindingsState> { - static void success(const auto & in, BindingsState & b, ExprState & s, State & ps) { - if (!b.attrs.dynamicAttrs.empty()) - throw ParseError({ - .msg = HintFmt("dynamic attributes not allowed in let"), - .pos = ps.positions[ps.at(in)] - }); - - s.pushExpr<ExprLet>(ps.at(in), std::make_unique<ExprAttrs>(std::move(b.attrs)), b->popExprOnly()); - } -}; - -template<> struct BuildAST<grammar::expr::if_> { - static void apply(const auto & in, ExprState & s, State & ps) { - auto else_ = s.popExprOnly(), then = s.popExprOnly(), cond = s.popExprOnly(); - s.pushExpr<ExprIf>(ps.at(in), ps.at(in), std::move(cond), std::move(then), std::move(else_)); - } -}; - -template<> struct BuildAST<grammar::expr> : change_head<ExprState> { - static void success0(ExprState & inner, ExprState & outer, State & ps) { - outer.exprs.push_back(inner.finish(ps)); - } -}; - -} -} +// Linter complains that this is a "suspicious include of file with '.cc' extension". +// While that is correct and generally not great, it is one of the less bad options to pick +// in terms of diff noise. +// NOLINTNEXTLINE(bugprone-suspicious-include) +#include "parser-impl1.inc.cc" namespace nix { @@ -884,7 +38,6 @@ Expr * EvalState::parse( exprSymbols, featureSettings, }; - parser::ExprState x; assert(length >= 2); assert(text[length - 1] == 0); @@ -893,7 +46,12 @@ Expr * EvalState::parse( p::string_input<p::tracking_mode::lazy> inp{std::string_view{text, length}, "input"}; try { - p::parse<parser::grammar::root, parser::BuildAST, parser::Control>(inp, x, s); + parser::v1::ExprState x; + p::parse<parser::grammar::v1::root, parser::v1::BuildAST, parser::v1::Control>(inp, x, s); + + auto [_pos, result] = x.finish(s); + result->bindVars(*this, staticEnv); + return result.release(); } catch (p::parse_error & e) { auto pos = e.positions().back(); throw ParseError({ @@ -901,10 +59,6 @@ Expr * EvalState::parse( .pos = positions[s.positions.add(s.origin, pos.byte)] }); } - - auto [_pos, result] = x.finish(s); - result->bindVars(*this, staticEnv); - return result.release(); } } |