Disallowed some semantically incorrect syntax to improve code consistency.

8 files changed, 121 insertions, 112 deletions

diff --git a/spec/inputs/upvalue_func.yue b/spec/inputs/upvalue_func.yue
index d4b3273..378bf60 100644
--- a/spec/inputs/upvalue_func.yue
+++ b/spec/inputs/upvalue_func.yue
@@ -208,20 +208,21 @@ GameEngine\schedule (deltaTime) -> -- closure 1
 -- test cases from issue
 do
         buff_strength = (char, item) ->
-                item.buffer.strength? char.stats.strength?::ref()
+                item.buffer.strength? char.stats.strength?::ref!
 
         local debug_env_before, debug_env_after
 
         exe_func = (func, env) ->
                 ok, ... = try
-                        debug_env_before(env)
-                        func(env)
-                        debug_env_after(env)
+                        debug_env_before env
+                        func env
+                        debug_env_after env
                 catch ex
                         -- accessing ex and error
                         error ex
-                        return ex
+                        -- implicit return
+                        ex
                 if ok
                         return ...
                 else
-                        os.exit(1)
+                        os.exit 1
diff --git a/spec/outputs/5.1/attrib.lua b/spec/outputs/5.1/attrib.lua
index c48c72c..dc1285c 100644
--- a/spec/outputs/5.1/attrib.lua
+++ b/spec/outputs/5.1/attrib.lua
@@ -44,18 +44,6 @@ do
         }
         a, b = _obj_0[1], _obj_0[2]
 end
-local _anon_func_0 = function(_close_1, error, f, _arg_0, ...)
-        do
-                local _ok_0 = _arg_0
-                _close_1(f)
-                if _ok_0 then
-                        return ...
-                else
-                        return error(...)
-                end
-        end
-end
-local _anon_func_1 = function() end
 do
         local v
         if flag then
@@ -82,28 +70,17 @@ do
                         f = _with_0
                 end
                 local _close_1 = assert(getmetatable(f).__close)
-                return _anon_func_0(_close_1, error, f, pcall(_anon_func_1))
+                return (function(_arg_0, ...)
+                        local _ok_0 = _arg_0
+                        _close_1(f)
+                        if _ok_0 then
+                                return ...
+                        else
+                                return error(...)
+                        end
+                end)(pcall(function() end))
         end))
 end
-local _anon_func_2 = function(_close_1, d, error, _arg_0, ...)
-        do
-                local _ok_0 = _arg_0
-                _close_1(d)
-                if _ok_0 then
-                        return ...
-                else
-                        return error(...)
-                end
-        end
-end
-local _anon_func_3 = function(a, b)
-        if a ~= nil then
-                return a
-        else
-                return b
-        end
-end
-local _anon_func_4 = function() end
 do
         local a
         if true then
@@ -133,37 +110,29 @@ do
                         end
                 end
                 local d
-                if _anon_func_3(a, b) then
+                if (function()
+                        if a ~= nil then
+                                return a
+                        else
+                                return b
+                        end
+                end)() then
                         d = {
                                 value = value
                         }
                 end
                 local _close_1 = assert(getmetatable(d).__close)
-                return _anon_func_2(_close_1, d, error, pcall(_anon_func_4))
+                return (function(_arg_0, ...)
+                        local _ok_0 = _arg_0
+                        _close_1(d)
+                        if _ok_0 then
+                                return ...
+                        else
+                                return error(...)
+                        end
+                end)(pcall(function() end))
         end))
 end
-local _anon_func_5 = function(_, _close_1, error, _arg_0, ...)
-        do
-                local _ok_0 = _arg_0
-                _close_1(_)
-                if _ok_0 then
-                        return ...
-                else
-                        return error(...)
-                end
-        end
-end
-local _anon_func_6 = function(_, _close_2, error, _arg_0, ...)
-        do
-                local _ok_0 = _arg_0
-                _close_2(_)
-                if _ok_0 then
-                        return ...
-                else
-                        return error(...)
-                end
-        end
-end
 do
         local _
         do
@@ -187,14 +156,30 @@ do
                         end
                 })
                 local _close_1 = assert(getmetatable(_).__close)
-                return _anon_func_5(_, _close_1, error, pcall(function()
+                return (function(_arg_0, ...)
+                        local _ok_0 = _arg_0
+                        _close_1(_)
+                        if _ok_0 then
+                                return ...
+                        else
+                                return error(...)
+                        end
+                end)(pcall(function()
                         local _ = setmetatable({ }, {
                                 __close = function()
                                         return print("first")
                                 end
                         })
                         local _close_2 = assert(getmetatable(_).__close)
-                        return _anon_func_6(_, _close_2, error, pcall(function()
+                        return (function(_arg_0, ...)
+                                local _ok_0 = _arg_0
+                                _close_2(_)
+                                if _ok_0 then
+                                        return ...
+                                else
+                                        return error(...)
+                                end
+                        end)(pcall(function()
                                 return print("third")
                         end))
                 end))
@@ -211,29 +196,6 @@ def = function(item)
         _defers[#_defers + 1] = item
         return _defers
 end
-local _anon_func_7 = function(_, _close_1, error, _arg_0, ...)
-        do
-                local _ok_0 = _arg_0
-                _close_1(_)
-                if _ok_0 then
-                        return ...
-                else
-                        return error(...)
-                end
-        end
-end
-local _anon_func_8 = function(_, _close_2, error, _arg_0, ...)
-        do
-                local _ok_0 = _arg_0
-                _close_2(_)
-                if _ok_0 then
-                        return ...
-                else
-                        return error(...)
-                end
-        end
-end
-local _anon_func_9 = function() end
 do
         local _ = def(function()
                 return print(3)
@@ -252,12 +214,28 @@ do
                         return print(2)
                 end)
                 local _close_1 = assert(getmetatable(_).__close)
-                return _anon_func_7(_, _close_1, error, pcall(function()
+                return (function(_arg_0, ...)
+                        local _ok_0 = _arg_0
+                        _close_1(_)
+                        if _ok_0 then
+                                return ...
+                        else
+                                return error(...)
+                        end
+                end)(pcall(function()
                         local _ = def(function()
                                 return print(1)
                         end)
                         local _close_2 = assert(getmetatable(_).__close)
-                        return _anon_func_8(_, _close_2, error, pcall(_anon_func_9))
+                        return (function(_arg_0, ...)
+                                local _ok_0 = _arg_0
+                                _close_2(_)
+                                if _ok_0 then
+                                        return ...
+                                else
+                                        return error(...)
+                                end
+                        end)(pcall(function() end))
                 end))
         end))
 end
diff --git a/src/yuescript/ast.cpp b/src/yuescript/ast.cpp
index 2bdac81..99ab8f5 100644
--- a/src/yuescript/ast.cpp
+++ b/src/yuescript/ast.cpp
@@ -54,8 +54,8 @@ bool ast_node::visit_child(const std::function<bool(ast_node*)>&) {
 */
 void ast_container::construct(ast_stack& st) {
         for (ast_member_vector::reverse_iterator it = m_members.rbegin();
-                 it != m_members.rend();
-                 ++it) {
+                it != m_members.rend();
+                ++it) {
                 ast_member* member = *it;
                 member->construct(st);
         }
diff --git a/src/yuescript/parser.cpp b/src/yuescript/parser.cpp
index 5d0773c..f0ddd06 100644
--- a/src/yuescript/parser.cpp
+++ b/src/yuescript/parser.cpp
@@ -160,8 +160,8 @@ public:
         // execute all the parse procs
         void do_parse_procs(void* d) const {
                 for (_match_vector::const_iterator it = m_matches.begin();
-                         it != m_matches.end();
-                         ++it) {
+                        it != m_matches.end();
+                        ++it) {
                         const _match& m = *it;
                         parse_proc p = _private::get_parse_proc(*m.m_rule);
                         p(m.m_begin, m.m_end, d);
@@ -262,7 +262,7 @@ private:
         bool _parse(_context& con) const {
                 for (auto it = m_string.begin(),
                                   end = m_string.end();
-                         ;) {
+                        ;) {
                         if (it == end) return true;
                         if (con.end()) break;
                         if (con.symbol() != *it) break;
diff --git a/src/yuescript/parser.hpp b/src/yuescript/parser.hpp
index 5ab327f..c544785 100644
--- a/src/yuescript/parser.hpp
+++ b/src/yuescript/parser.hpp
@@ -433,8 +433,8 @@ bool start_with(input& i, rule& g, error_list& el, void* st, void* ud);
 template <class T>
 T& operator<<(T& stream, const input_range& ir) {
         for (input::const_iterator it = ir.m_begin.m_it;
-                 it != ir.m_end.m_it;
-                 ++it) {
+                it != ir.m_end.m_it;
+                ++it) {
                 stream << (typename T::char_type) * it;
         }
         return stream;
diff --git a/src/yuescript/yue_ast.h b/src/yuescript/yue_ast.h
index cffc92d..8063517 100644
--- a/src/yuescript/yue_ast.h
+++ b/src/yuescript/yue_ast.h
@@ -277,6 +277,7 @@ AST_END(ExpList)
 
 AST_NODE(Return)
         bool allowBlockMacroReturn = false;
+        bool explicitReturn = true;
         ast_sel<false, TableBlock_t, ExpListLow_t> valueList;
         AST_MEMBER(Return, &valueList)
 AST_END(Return)
@@ -766,6 +767,7 @@ AST_NODE(FunLit)
         ast_ptr<true, FnArrow_t> arrow;
         ast_ptr<false, Body_t> body;
         bool noRecursion = false;
+        bool isAnon = false;
         AST_MEMBER(FunLit, &argsDef, &defaultReturn, &arrow, &body)
 AST_END(FunLit)
 
diff --git a/src/yuescript/yue_compiler.cpp b/src/yuescript/yue_compiler.cpp
index b44b697..ef8e59e 100644
--- a/src/yuescript/yue_compiler.cpp
+++ b/src/yuescript/yue_compiler.cpp
@@ -75,7 +75,7 @@ static std::unordered_set<std::string> Metamethods = {
         "close"s // Lua 5.4
 };
 
-const std::string_view version = "0.25.3"sv;
+const std::string_view version = "0.25.4"sv;
 const std::string_view extension = "yue"sv;
 
 class CompileError : public std::logic_error {
@@ -3777,6 +3777,7 @@ private:
                                 }
                                 case ExpUsage::Return: {
                                         auto ret = x->new_ptr<Return_t>();
+                                        ret->explicitReturn = false;
                                         auto expListLow = x->new_ptr<ExpListLow_t>();
                                         expListLow->exprs.push_back(arg);
                                         ret->valueList.set(expListLow);
@@ -4007,6 +4008,7 @@ private:
                                                 auto expListLow = exp->new_ptr<ExpListLow_t>();
                                                 expListLow->exprs.push_back(e);
                                                 auto returnNode = exp->new_ptr<Return_t>();
+                                                returnNode->explicitReturn = false;
                                                 returnNode->valueList.set(expListLow);
                                                 transformReturn(returnNode, out);
                                                 break;
@@ -4039,7 +4041,7 @@ private:
                 }) != traversal::Stop;
         }
 
-        std::optional<std::pair<std::string, str_list>> getUpValueFuncFromBlock(Block_t* block, str_list* ensureArgListInTheEnd, bool noGlobalVarPassing) {
+        std::optional<std::pair<std::string, str_list>> getUpValueFuncFromBlock(Block_t* block, str_list* ensureArgListInTheEnd, bool noGlobalVarPassing, bool blockRewrite) {
                 if (_funcLevel <= 1) return std::nullopt;
                 auto result = block->traverse([&](ast_node* node) {
                         switch (node->get_id()) {
@@ -4138,6 +4140,7 @@ private:
                                         }
                                 }
                                 auto funLit = toAst<FunLit_t>("("s + join(args, ","sv) + ")-> nil"s, x);
+                                funLit->isAnon = blockRewrite ? false : true;
                                 funLit->body->content.set(newBlock);
                                 funLit->noRecursion = true;
                                 auto simpleValue = x->new_ptr<SimpleValue_t>();
@@ -4159,16 +4162,17 @@ private:
                 return std::nullopt;
         }
 
-        std::optional<std::pair<std::string, str_list>> upValueFuncFrom(Block_t* block, str_list* ensureArgListInTheEnd = nullptr, bool noGlobalVarPassing = false) {
+        std::optional<std::pair<std::string, str_list>> upValueFuncFromBlock(Block_t* block, str_list* ensureArgListInTheEnd, bool noGlobalVarPassing, bool blockRewrite) {
                 if (checkUpValueFuncAvailable(block)) {
-                        return getUpValueFuncFromBlock(block, ensureArgListInTheEnd, noGlobalVarPassing);
+                        return getUpValueFuncFromBlock(block, ensureArgListInTheEnd, noGlobalVarPassing, blockRewrite);
                 }
                 return std::nullopt;
         }
 
-        std::optional<std::pair<std::string, str_list>> upValueFuncFrom(Exp_t* exp, str_list* ensureArgListInTheEnd = nullptr) {
+        std::optional<std::pair<std::string, str_list>> upValueFuncFromExp(Exp_t* exp, str_list* ensureArgListInTheEnd, bool blockRewrite) {
                 if (checkUpValueFuncAvailable(exp)) {
                         auto returnNode = exp->new_ptr<Return_t>();
+                        returnNode->explicitReturn = false;
                         auto returnList = exp->new_ptr<ExpListLow_t>();
                         returnList->exprs.push_back(exp);
                         returnNode->valueList.set(returnList);
@@ -4176,13 +4180,13 @@ private:
                         auto stmt = exp->new_ptr<Statement_t>();
                         stmt->content.set(returnNode);
                         block->statements.push_back(stmt);
-                        return getUpValueFuncFromBlock(block, ensureArgListInTheEnd, false);
+                        return getUpValueFuncFromBlock(block, ensureArgListInTheEnd, false, blockRewrite);
                 }
                 return std::nullopt;
         }
 
         bool transformAsUpValueFunc(Exp_t* exp, str_list& out) {
-                auto result = upValueFuncFrom(exp);
+                auto result = upValueFuncFromExp(exp, nullptr, false);
                 if (result) {
                         auto [funcName, args] = std::move(*result);
                         auto newChainValue = toAst<ChainValue_t>(funcName + '(' + join(args, ","sv) + ')', exp);
@@ -4258,6 +4262,7 @@ private:
                                 _buf << indent() << "else"s << nll(x);
                                 temp.push_back(clearBuf());
                                 auto ret = x->new_ptr<Return_t>();
+                                ret->explicitReturn = false;
                                 auto retList = x->new_ptr<ExpListLow_t>();
                                 retList->exprs.push_back(exp->nilCoalesed);
                                 ret->valueList.set(retList);
@@ -4385,7 +4390,11 @@ private:
         }
 
         void transformFunLit(FunLit_t* funLit, str_list& out) {
-                pushUserFunctionScope();
+                if (funLit->isAnon) {
+                        pushAnonFunctionScope();
+                } else {
+                        pushUserFunctionScope();
+                }
                 _varArgs.push({false, false});
                 bool isFatArrow = _parser.toString(funLit->arrow) == "=>"sv;
                 pushScope();
@@ -4419,6 +4428,7 @@ private:
                         }
                         if (funLit->defaultReturn.is<ExpListLow_t>()) {
                                 auto returnNode = newBlock->new_ptr<Return_t>();
+                                returnNode->explicitReturn = false;
                                 returnNode->valueList.set(funLit->defaultReturn);
                                 auto stmt = newBlock->new_ptr<Statement_t>();
                                 stmt->content.set(returnNode);
@@ -4594,7 +4604,7 @@ private:
                                 transformBlock(newBlock, out, usage, assignList, isRoot);
                                 return;
                         } else if (auto expListAssign = stmt->content.as<ExpListAssign_t>();
-                                           expListAssign && expListAssign->action && expListAssign->action.is<Assign_t>()) {
+                                expListAssign && expListAssign->action && expListAssign->action.is<Assign_t>()) {
                                 BLOCK_START
                                 auto unary = singleUnaryExpFrom(expListAssign->expList->exprs.back());
                                 BREAK_IF(!unary);
@@ -4693,7 +4703,7 @@ private:
                                         doNode->body.set(newBody);
                                         auto simpleValue = x->new_ptr<SimpleValue_t>();
                                         simpleValue->value.set(doNode);
-                                        if (auto result = upValueFuncFrom(newExp(simpleValue, x), &argNames)) {
+                                        if (auto result = upValueFuncFromExp(newExp(simpleValue, x), &argNames, true)) {
                                                 auto [funcName, args] = std::move(*result);
                                                 str_list finalArgs;
                                                 for (const auto& arg : args) {
@@ -4903,6 +4913,7 @@ private:
                                 auto expListLow = x->new_ptr<ExpListLow_t>();
                                 expListLow->exprs.dup(expList->exprs);
                                 auto returnNode = x->new_ptr<Return_t>();
+                                returnNode->explicitReturn = false;
                                 returnNode->valueList.set(expListLow);
                                 returnNode->allowBlockMacroReturn = true;
                                 last->content.set(returnNode);
@@ -5258,6 +5269,11 @@ private:
                         if (!target) target = returnNode;
                         throw CompileError("can not mix use of return and export statements in module scope"sv, target);
                 }
+                if (returnNode->explicitReturn && _funcStates.top().isAnon) {
+                        ast_node* target = returnNode->valueList.get();
+                        if (!target) target = returnNode;
+                        throw CompileError("explicit return statement is not allowed in this context"sv, target);
+                }
                 if (auto valueList = returnNode->valueList.as<ExpListLow_t>()) {
                         if (valueList->exprs.size() == 1) {
                                 auto exp = static_cast<Exp_t*>(valueList->exprs.back());
@@ -5712,6 +5728,7 @@ private:
                                 case ExpUsage::Closure: {
                                         auto exp = newExp(partTwo, x);
                                         auto ret = x->new_ptr<Return_t>();
+                                        ret->explicitReturn = false;
                                         auto expListLow = x->new_ptr<ExpListLow_t>();
                                         expListLow->exprs.push_back(exp);
                                         ret->valueList.set(expListLow);
@@ -5810,6 +5827,7 @@ private:
                                 case ExpUsage::Closure:
                                 case ExpUsage::Return: {
                                         auto returnNode = x->new_ptr<Return_t>();
+                                        returnNode->explicitReturn = false;
                                         auto expListLow = x->new_ptr<ExpListLow_t>();
                                         expListLow->exprs.push_back(funLit);
                                         returnNode->valueList.set(expListLow);
@@ -5944,6 +5962,7 @@ private:
                                                 switch (usage) {
                                                         case ExpUsage::Closure: {
                                                                 auto returnNode = x->new_ptr<Return_t>();
+                                                                returnNode->explicitReturn = false;
                                                                 auto values = x->new_ptr<ExpListLow_t>();
                                                                 values->exprs.push_back(newChainExp);
                                                                 returnNode->valueList.set(values);
@@ -5957,6 +5976,7 @@ private:
                                                         }
                                                         case ExpUsage::Return: {
                                                                 auto returnNode = x->new_ptr<Return_t>();
+                                                                returnNode->explicitReturn = false;
                                                                 auto values = x->new_ptr<ExpListLow_t>();
                                                                 values->exprs.push_back(newChainExp);
                                                                 returnNode->valueList.set(values);
@@ -6629,6 +6649,7 @@ private:
                                                 auto expListLow = x->new_ptr<ExpListLow_t>();
                                                 expListLow->exprs.push_back(node);
                                                 auto returnNode = x->new_ptr<Return_t>();
+                                                returnNode->explicitReturn = false;
                                                 returnNode->valueList.set(expListLow);
                                                 transformReturn(returnNode, out);
                                                 break;
@@ -7612,6 +7633,7 @@ private:
                                         simpleValue->value.set(tableLit);
                                         auto exp = newExp(simpleValue, x);
                                         auto returnNode = x->new_ptr<Return_t>();
+                                        returnNode->explicitReturn = false;
                                         auto expList = x->new_ptr<ExpListLow_t>();
                                         expList->exprs.push_back(exp);
                                         returnNode->valueList.set(expList);
@@ -8296,6 +8318,7 @@ private:
                 } else {
                         auto accum = transformForInner(forNode, temp);
                         auto returnNode = x->new_ptr<Return_t>();
+                        returnNode->explicitReturn = false;
                         auto expListLow = toAst<ExpListLow_t>(accum, x);
                         returnNode->valueList.set(expListLow);
                         transformReturn(returnNode, temp);
@@ -8395,6 +8418,7 @@ private:
                 } else {
                         auto accum = transformForEachInner(forEach, temp);
                         auto returnNode = x->new_ptr<Return_t>();
+                        returnNode->explicitReturn = false;
                         auto expListLow = toAst<ExpListLow_t>(accum, x);
                         returnNode->valueList.set(expListLow);
                         transformReturn(returnNode, temp);
@@ -9618,11 +9642,13 @@ private:
                 auto x = tryNode;
                 ast_ptr<true, Exp_t> errHandler;
                 if (tryNode->catchBlock) {
-                        auto errHandleStr = "("s + variableToString(tryNode->catchBlock->err) + ")->"s;
-                        errHandler.set(toAst<Exp_t>(errHandleStr, x->func));
+                        auto catchBlock = tryNode->catchBlock.get();
+                        auto errHandleStr = "("s + variableToString(catchBlock->err) + ")->"s;
+                        errHandler.set(toAst<Exp_t>(errHandleStr, catchBlock));
                         auto funLit = simpleSingleValueFrom(errHandler)->value.to<FunLit_t>();
-                        auto body = x->new_ptr<Body_t>();
-                        body->content.set(tryNode->catchBlock->block);
+                        funLit->isAnon = true;
+                        auto body = catchBlock->block->new_ptr<Body_t>();
+                        body->content.set(catchBlock->block);
                         funLit->body.set(body);
                 }
                 ast_sel<false, Block_t, Exp_t> tryFunc;
@@ -9700,7 +9726,7 @@ private:
                 }
                 if (auto tryBlock = tryFunc.as<Block_t>()) {
                         if (getLuaTarget(tryBlock) >= 502 || !errHandler) {
-                                if (auto result = upValueFuncFrom(tryBlock, nullptr, true)) {
+                                if (auto result = upValueFuncFromBlock(tryBlock, nullptr, true, false)) {
                                         auto [funcName, args] = std::move(*result);
                                         if (errHandler) {
                                                 auto xpcall = toAst<ChainValue_t>("xpcall()", x);
@@ -9729,6 +9755,7 @@ private:
                         }
                         auto tryExp = toAst<Exp_t>("->"sv, x);
                         auto funLit = simpleSingleValueFrom(tryExp)->value.to<FunLit_t>();
+                        funLit->isAnon = true;
                         auto body = x->new_ptr<Body_t>();
                         body->content.set(tryBlock);
                         funLit->body.set(body);
@@ -9762,6 +9789,7 @@ private:
                         if (errHandler && getLuaTarget(x) < 502) {
                                 auto tryExp = toAst<Exp_t>("->"sv, x);
                                 auto funLit = simpleSingleValueFrom(tryExp)->value.to<FunLit_t>();
+                                funLit->isAnon = true;
                                 auto expList = x->new_ptr<ExpList_t>();
                                 expList->exprs.push_back(tryFunc);
                                 auto expListAssign = x->new_ptr<ExpListAssign_t>();
diff --git a/src/yuescript/yue_parser.cpp b/src/yuescript/yue_parser.cpp
index 93787cd..d7af780 100644
--- a/src/yuescript/yue_parser.cpp
+++ b/src/yuescript/yue_parser.cpp
@@ -1167,7 +1167,7 @@ std::string ParseInfo::errorMessage(std::string_view msg, int errLine, int errCo
         }
         auto line = Converter{}.to_bytes(std::wstring(begin, end));
         while (col < static_cast<int>(line.size())
-                && (line[col] == ' ' || line[col] == '\t')) {
+                   && (line[col] == ' ' || line[col] == '\t')) {
                 col++;
         }
         Utils::replace(line, "\t"sv, " "sv);