Add missing tests for ASTNodeBuiltinFunctionExpressionBuilder

Also remove the treatment of tuple of function arguments, since this kind of argument cannot be defined in the language (by now?).

src/language/ast/ASTNodeBuiltinFunctionExpressionBuilder.cpp

@@ -231,9 +231,6 @@ ASTNodeBuiltinFunctionExpressionBuilder::_getArgumentConverter(const ASTNodeData
       }
       case ASTNodeDataType::double_t: {
         return std::make_unique<FunctionTupleArgumentConverter<ParameterContentT, double>>(argument_number);
-      }
-      case ASTNodeDataType::function_t: {
-        return std::make_unique<FunctionTupleArgumentConverter<ParameterContentT, FunctionSymbolId>>(argument_number);
       }
         // LCOV_EXCL_START
       default: {
@@ -513,11 +510,13 @@ ASTNodeBuiltinFunctionExpressionBuilder::_buildArgumentProcessors(
   const size_t parameters_number = parameter_type_list.size();
 
   if (arguments_number != parameters_number) {
+    // LCOV_EXCL_START
     std::ostringstream error_message;
     error_message << "bad number of arguments: expecting " << rang::fgB::yellow << parameters_number
                   << rang::style::reset << rang::style::bold << ", provided " << rang::fgB::yellow << arguments_number
                   << rang::style::reset;
-    throw ParseError(error_message.str(), argument_nodes.begin());
+    throw UnexpectedError(error_message.str());
+    // LCOV_EXCL_STOP
   }
 
   for (size_t i = 0; i < arguments_number; ++i) {