Fix Scopes (#38)

* fix scopes and add extra type error check

* add tests

* add one more test

* add another scope test

include/ast/passes/define.h → include/ast/passes/def_ref.h

@@ -5,13 +5,17 @@
 #include "ast/symbol/symbol.h"
 #include "ast/symbol/symbol_table.h"
 
-class Define : public Pass {
+class DefRef : public Pass {
    private:
     shared_ptr<SymbolTable> symbol_table;
+    bool is_builtin(std::string name);
 
    public:
-    explicit Define(shared_ptr<SymbolTable> symbol_table);
+    explicit DefRef(shared_ptr<SymbolTable> symbol_table);
+    void visit_block(shared_ptr<ast::Block>) override;
     void visit_declaration(shared_ptr<ast::Declaration>) override;
     void visit_parameter(shared_ptr<ast::Parameter>) override;
     void visit_function(shared_ptr<ast::Function>) override;
+    void visit_variable(shared_ptr<ast::Variable>) override;
+    void visit_call(shared_ptr<ast::Call>) override;
 };

src/CMakeLists.txt

@@ -19,8 +19,7 @@ set(
   "${CMAKE_CURRENT_SOURCE_DIR}/ast/symbol/function_symbol.cpp"
   "${CMAKE_CURRENT_SOURCE_DIR}/ast/ast.cpp"
   "${CMAKE_CURRENT_SOURCE_DIR}/ast/passes/pass.cpp"
-  "${CMAKE_CURRENT_SOURCE_DIR}/ast/passes/define.cpp"
-  "${CMAKE_CURRENT_SOURCE_DIR}/ast/passes/reference.cpp"
+  "${CMAKE_CURRENT_SOURCE_DIR}/ast/passes/def_ref.cpp"
   "${CMAKE_CURRENT_SOURCE_DIR}/ast/passes/type_check.cpp"
   "${CMAKE_CURRENT_SOURCE_DIR}/ast/passes/builtin.cpp"
   "${CMAKE_CURRENT_SOURCE_DIR}/shared/type.cpp"

src/ast/ast.cpp

@@ -260,13 +260,15 @@ void ast::Function::xml(int level) {
               << type->get_name() << "\" name=\"" << name << "\" ref_name=\""
               << ref_name << "\">\n";
 
-    std::cout << std::string((level + 1) * 4, ' ') << "<parameters>\n";
-    for (const auto& param : params) {
-        param->xml(level + 2);
+    if (params.size() > 0) {
+        std::cout << std::string((level + 1) * 4, ' ') << "<parameters>\n";
+        for (const auto& param : params) {
+            param->xml(level + 2);
+        }
+        std::cout << std::string((level + 1) * 4, ' ') << "</parameters>\n";
     }
-    std::cout << std::string((level + 1) * 4, ' ') << "</parameters>\n";
-    body->xml(level + 1);
 
+    body->xml(level + 1);
     std::cout << std::string(level * 4, ' ') << "</function>\n";
 }
 
@@ -294,16 +296,17 @@ std::string ast::Call::get_name() {
 }
 
 void ast::Call::xml(int level) {
-    std::cout << std::string(level * 4, ' ') << "<call name=\"" << this->name
-              << "\" ref_name=\"" << this->function->get_ref_name()
-              << "\" type=\"" << this->type->get_name() << "\">\n";
+    std::string ref = function ? function->get_ref_name() : "(unset)";
+    std::cout << std::string(level * 4, ' ') << "<call name=\"" << name
+              << "\" ref_name=\"" << ref << "\" type=\"" << type->get_name()
+              << "\">\n";
 
     if (arguments.size() > 0) {
-        std::cout << std::string((level + 1) * 4, ' ') << "<args>\n";
+        std::cout << std::string((level + 1) * 4, ' ') << "<arguments>\n";
         for (auto const& a : arguments) {
             a->xml(level + 2);
         }
-        std::cout << std::string((level + 1) * 4, ' ') << "</args>\n";
+        std::cout << std::string((level + 1) * 4, ' ') << "</arguments>\n";
     }
 
     std::cout << std::string(level * 4, ' ') << "</call>\n";

src/ast/builder.cpp

@@ -1,3 +1,4 @@
+#include <any>
 #include <stdexcept>
 #include <vector>
 
@@ -6,8 +7,10 @@
 #include "ast/builder.h"
 #include "shared/context.h"
 
+using std::any_cast;
+
 #define cast_node(a, b) \
-    (dynamic_pointer_cast<a>(std::any_cast<shared_ptr<ast::Node>>(b)))
+    (dynamic_pointer_cast<a>(any_cast<shared_ptr<ast::Node>>(b)))
 #define to_node(a) static_cast<shared_ptr<ast::Node>>(a)
 
 Builder::Builder(shared_ptr<SymbolTable> symbol_table) {
@@ -147,7 +150,7 @@ std::any Builder::visitIdentifier(FusionParser::IdentifierContext* ctx) {
 
 std::any Builder::visitBlock(FusionParser::BlockContext* ctx) {
     Token* token = ctx->L_CURLY()->getSymbol();
-    auto block = std::make_shared<ast::Block>(token);
+    auto block = make_shared<ast::Block>(token);
 
     for (auto const& s : ctx->statement()) {
         shared_ptr<ast::Node> node = cast_node(ast::Node, visit(s));
@@ -163,16 +166,16 @@ std::any Builder::visitVariable(FusionParser::VariableContext* ctx) {
     std::string name = ctx->ID()->getText();
 
     ast::Qualifier qualifier =
-        std::any_cast<ast::Qualifier>(visit(ctx->qualifier()));
-    TypePtr type = std::any_cast<TypePtr>(visit(ctx->type()));
+        any_cast<ast::Qualifier>(visit(ctx->qualifier()));
+    TypePtr type = any_cast<TypePtr>(visit(ctx->type()));
 
     auto var = make_shared<ast::Variable>(qualifier, type, name, token);
     return to_node(var);
 }
 
 std::any Builder::visitFunction(FusionParser::FunctionContext* ctx) {
     Token* token = ctx->FUNCTION()->getSymbol();
-    TypePtr type = std::any_cast<TypePtr>(visit(ctx->type()));
+    TypePtr type = any_cast<TypePtr>(visit(ctx->type()));
     std::string name = ctx->ID()->getText();
     auto block = cast_node(ast::Block, visit(ctx->block()));
 

src/ast/passes/def_ref.cpp

@@ -0,0 +1,116 @@
+#include "ast/passes/def_ref.h"
+#include "ast/ast.h"
+#include "ast/symbol/function_symbol.h"
+#include "errors.h"
+
+DefRef::DefRef(shared_ptr<SymbolTable> symbol_table) : Pass("DefRef") {
+    this->symbol_table = symbol_table;
+}
+
+void DefRef::visit_block(shared_ptr<ast::Block> node) {
+    symbol_table->push();
+    for (const auto& node : node->nodes) {
+        visit(node);
+    }
+    symbol_table->pop();
+}
+
+void DefRef::visit_declaration(shared_ptr<ast::Declaration> node) {
+    if (symbol_table->resolve_local(node->var->get_name()).has_value()) {
+        throw SymbolError(
+            node->token->getLine(),
+            "variable " + node->var->get_name() + " already defined");
+    }
+
+    shared_ptr<ast::Variable> var = node->var;
+    shared_ptr<VariableSymbol> sym = make_shared<VariableSymbol>(var);
+
+    symbol_table->define(sym);
+
+    visit(node->expr);
+}
+
+void DefRef::visit_parameter(shared_ptr<ast::Parameter> node) {
+    shared_ptr<ast::Variable> var = node->var;
+    if (symbol_table->resolve_local(var->get_name()).has_value()) {
+        throw SymbolError(
+            node->token->getLine(),
+            "parameter " + node->var->get_name() + " already defined");
+    }
+
+    shared_ptr<VariableSymbol> sym = make_shared<VariableSymbol>(var);
+    symbol_table->define(sym);
+}
+
+void DefRef::visit_function(shared_ptr<ast::Function> node) {
+    if (symbol_table->resolve_bottom(name).has_value()) {
+        throw SymbolError(node->token->getLine(),
+                          "function " + node->get_name() + " already defined");
+    }
+
+    shared_ptr<FunctionSymbol> sym =
+        std::make_shared<FunctionSymbol>(node, symbol_table->current_scope);
+    symbol_table->define(sym);
+
+    symbol_table->push();
+    for (const auto& param : node->params) {
+        visit(param);
+    }
+
+    symbol_table->push();
+    visit(node->body);
+    symbol_table->pop();
+    symbol_table->pop();
+}
+
+void DefRef::visit_variable(shared_ptr<ast::Variable> node) {
+    std::optional<SymbolPtr> var = symbol_table->resolve(node->get_name());
+    size_t line = node->token->getLine();
+    if (!var.has_value()) {
+        throw SymbolError(line,
+                          "use of undefined variable: " + node->get_name());
+    }
+
+    shared_ptr<VariableSymbol> vs =
+        dynamic_pointer_cast<VariableSymbol>(var.value());
+    if (vs == nullptr) {
+        throw SymbolError(line, node->get_name() + " is not a variable");
+    }
+
+    node->set_type(vs->variable->get_type());
+    node->set_qualifier(vs->variable->get_qualifier());
+    node->set_ref_name(vs->variable->get_ref_name());
+}
+
+void DefRef::visit_call(shared_ptr<ast::Call> node) {
+    for (const auto& arg : node->arguments) {
+        visit(arg);
+    }
+
+    std::string name = node->get_name();
+    if (is_builtin(name) && node->arguments.size() > 0) {
+        name += "_" + node->arguments[0]->get_type()->get_name();
+    }
+
+    std::optional<SymbolPtr> var = symbol_table->resolve(name);
+    size_t line = node->token->getLine();
+    if (!var.has_value()) {
+        throw SymbolError(line, "called undefined function: " + name);
+    }
+
+    shared_ptr<FunctionSymbol> vs =
+        dynamic_pointer_cast<FunctionSymbol>(var.value());
+    if (vs == nullptr) {
+        throw SymbolError(line, node->get_name() + " is not a function");
+    }
+
+    node->set_function(vs->function);
+}
+
+bool DefRef::is_builtin(std::string name) {
+    if (name == "print" || name == "println") {
+        return true;
+    }
+
+    return false;
+}

src/ast/passes/pass.cpp

@@ -1,8 +1,7 @@
 #include "ast/passes/pass.h"
 #include "ast/ast.h"
 #include "ast/passes/builtin.h"
-#include "ast/passes/define.h"
-#include "ast/passes/reference.h"
+#include "ast/passes/def_ref.h"
 #include "ast/passes/type_check.h"
 
 constexpr bool debug = false;
@@ -14,8 +13,7 @@ constexpr bool debug = false;
 void Pass::run_passes(std::shared_ptr<ast::Block> ast,
                       shared_ptr<SymbolTable> symtab) {
     std::vector<std::shared_ptr<Pass>> passes = {
-        std::make_shared<Define>(symtab),
-        std::make_shared<Reference>(symtab),
+        std::make_shared<DefRef>(symtab),
         std::make_shared<TypeCheck>(),
         std::make_shared<Builtin>(symtab),
     };