Get rid of buggy code (that coincidently was useless too) [#METR-2944].

dbms/include/DB/Parsers/ASTFunction.h

@@ -10,7 +10,7 @@
 namespace DB
 {
 
-/** Применение функции или оператора
+/** AST for function application or operator.
   */
 class ASTFunction : public ASTWithAlias
 {
@@ -25,41 +25,26 @@ public:
 		ARRAY_JOIN,
 	};
 
-	/// имя функции
 	String name;
-	/// аргументы
 	ASTPtr arguments;
-	/// параметры - для параметрических агрегатных функций. Пример: quantile(0.9)(x) - то, что в первых скобках - параметры.
+	/// parameters - for parametric aggregate function. Example: quantile(0.9)(x) - what in first parens are 'parameters'.
 	ASTPtr parameters;
 
 	FunctionKind kind{UNKNOWN};
 
-	enum class Genus
-	{
-		ORDINARY = 0,
-		CASE_WITH_EXPR,
-		CASE_WITHOUT_EXPR,
-		CASE_ARRAY
-	};
-
-	Genus genus{Genus::ORDINARY};
-
 public:
 	ASTFunction() = default;
 	ASTFunction(const StringRange range_) : ASTWithAlias(range_) {}
 
 	String getColumnName() const override;
 
-	/** Получить текст, который идентифицирует этот элемент. */
+	/** Get text identifying the AST node. */
 	String getID() const override;
 
 	ASTPtr clone() const override;
 
 protected:
 	void formatImplWithoutAlias(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const override;
-
-private:
-	void formatCase(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const;
 };
 
 

dbms/src/Interpreters/ExpressionAnalyzer.cpp

@@ -129,37 +129,6 @@ bool functionIsInOrGlobalInOperator(const String & name)
 	return name == "in" || name == "notIn" || name == "globalIn" || name == "globalNotIn";
 }
 
-/// Create a function uniquely identified by the first two parameters. If this
-/// function actually is a CASE expression, record this information.
-FunctionPtr getFunctionFromFactory(const String & name, const ASTFunction::Genus genus, const Context & context)
-{
-	FunctionPtr function = FunctionFactory::instance().get(name, context);
-
-	if (genus == ASTFunction::Genus::CASE_WITH_EXPR)
-	{
-		FunctionTransform * fun_transform = typeid_cast<FunctionTransform *>(&*function);
-		if (fun_transform == nullptr)
-			throw Exception{"Internal error", ErrorCodes::LOGICAL_ERROR};
-		fun_transform->setCaseMode();
-	}
-	else if (genus == ASTFunction::Genus::CASE_WITHOUT_EXPR)
-	{
-		FunctionMultiIf * fun_multi_if = typeid_cast<FunctionMultiIf *>(&*function);
-		if (fun_multi_if == nullptr)
-			throw Exception{"Internal error", ErrorCodes::LOGICAL_ERROR};
-		fun_multi_if->setCaseMode();
-	}
-	else if (genus == ASTFunction::Genus::CASE_ARRAY)
-	{
-		FunctionArray * fun_array = typeid_cast<FunctionArray *>(&*function);
-		if (fun_array == nullptr)
-			throw Exception{"Internal error", ErrorCodes::LOGICAL_ERROR};
-		fun_array->setCaseMode();
-	}
-
-	return function;
-}
-
 void removeDuplicateColumns(NamesAndTypesList & columns)
 {
 	std::set<String> names;
@@ -1753,7 +1722,7 @@ void ExpressionAnalyzer::getActionsImpl(ASTPtr ast, bool no_subqueries, bool onl
 				return;
 			}
 
-			const FunctionPtr & function = getFunctionFromFactory(node->name, node->genus, context);
+			const FunctionPtr & function = FunctionFactory::instance().get(node->name, context);
 
 			Names argument_names;
 			DataTypes argument_types;

dbms/src/Parsers/ASTFunction.cpp

@@ -66,13 +66,7 @@ void ASTFunction::formatImplWithoutAlias(const FormatSettings & settings, Format
 	nested_need_parens.need_parens = true;
 	nested_dont_need_parens.need_parens = false;
 
-	if ((genus == Genus::CASE_WITH_EXPR) || (genus == Genus::CASE_WITHOUT_EXPR))
-	{
-		formatCase(settings, state, frame);
-		return;
-	}
-
-	/// Стоит ли записать эту функцию в виде оператора?
+	/// Should this function to be written as operator?
 	bool written = false;
 	if (arguments && !parameters)
 	{
@@ -264,84 +258,4 @@ void ASTFunction::formatImplWithoutAlias(const FormatSettings & settings, Format
 	}
 }
 
-void ASTFunction::formatCase(const FormatSettings & settings, FormatState & state, FormatStateStacked frame) const
-{
-	static constexpr auto s_case = "CASE";
-	static constexpr auto s_when = "WHEN";
-	static constexpr auto s_then = "THEN";
-	static constexpr auto s_else = "ELSE";
-	static constexpr auto s_end = "END";
-	static constexpr auto s_ws = " ";
-
-	const ASTExpressionList * expr_list = static_cast<const ASTExpressionList *>(&*arguments);
-	const ASTs & args = expr_list->children;
-
-	frame.need_parens = false;
-
-	std::string indent_str = settings.one_line ? "" : std::string(4 * frame.indent, ' ');
-	std::string indent_str2 = settings.one_line ? "" : std::string(4 * (frame.indent + 1), ' ');
-
-	settings.ostr << (settings.hilite ? hilite_keyword : "") << s_case << s_ws
-		<< (settings.hilite ? hilite_none : "");
-
-	if (genus == Genus::CASE_WITH_EXPR)
-	{
-		args[0]->formatImpl(settings, state, frame);
-		settings.ostr << settings.nl_or_ws;
-
-		const ASTFunction * src_array_function = static_cast<const ASTFunction *>(&*args[1]);
-		const ASTExpressionList * src_expr_list = static_cast<const ASTExpressionList *>(&*src_array_function->arguments);
-
-		const ASTFunction * dst_array_function = static_cast<const ASTFunction *>(&*args[2]);
-		const ASTExpressionList * dst_expr_list = static_cast<const ASTExpressionList *>(&*dst_array_function->arguments);
-
-		size_t size = src_expr_list->children.size();
-
-		for (size_t i = 0; i < size; ++i)
-		{
-			settings.ostr << (settings.hilite ? hilite_keyword : "")
-				<< indent_str2 << s_when << s_ws;
-			src_expr_list->children[i]->formatImpl(settings, state, frame);
-			settings.ostr << s_ws;
-
-			settings.ostr << (settings.hilite ? hilite_keyword : "") << s_then << s_ws;
-			settings.ostr << hilite_none;
-			dst_expr_list->children[i]->formatImpl(settings, state, frame);
-			settings.ostr << settings.nl_or_ws;
-		}
-	}
-	else if (genus == Genus::CASE_WITHOUT_EXPR)
-	{
-		settings.ostr << settings.nl_or_ws;
-
-		for (size_t i = 0; i < (args.size() - 1); ++i)
-		{
-			if ((i % 2) == 0)
-			{
-				settings.ostr << (settings.hilite ? hilite_keyword : "")
-					<< indent_str2 << s_when << s_ws;
-				args[i]->formatImpl(settings, state, frame);
-				settings.ostr << " ";
-			}
-			else
-			{
-				settings.ostr << (settings.hilite ? hilite_keyword : "") << s_then << s_ws;
-				settings.ostr << hilite_none;
-				args[i]->formatImpl(settings, state, frame);
-				settings.ostr << settings.nl_or_ws;
-			}
-		}
-	}
-	else
-		throw Exception{"Invalid function genus", ErrorCodes::INVALID_FUNCTION_GENUS};
-
-	settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str2
-		<< s_else << s_ws;
-	settings.ostr << hilite_none;
-	args.back()->formatImpl(settings, state, frame);
-	settings.ostr << settings.nl_or_ws;
-
-	settings.ostr << (settings.hilite ? hilite_keyword : "") << indent_str << s_end;
-}
-
 }

dbms/src/Parsers/ParserCase.cpp

@@ -113,13 +113,11 @@ bool ParserCase::parseImpl(Pos & pos, Pos end, ASTPtr & node, Pos & max_parsed_p
 
 		auto src_array_function = std::make_shared<ASTFunction>(StringRange{begin, pos});
 		src_array_function->name = "array";
-		src_array_function->genus = ASTFunction::Genus::CASE_ARRAY;
 		src_array_function->arguments = src_expr_list;
 		src_array_function->children.push_back(src_array_function->arguments);
 
 		auto dst_array_function = std::make_shared<ASTFunction>(StringRange{begin, pos});
 		dst_array_function->name = "array";
-		dst_array_function->genus = ASTFunction::Genus::CASE_ARRAY;
 		dst_array_function->arguments = dst_expr_list;
 		dst_array_function->children.push_back(dst_array_function->arguments);
 
@@ -131,7 +129,6 @@ bool ParserCase::parseImpl(Pos & pos, Pos end, ASTPtr & node, Pos & max_parsed_p
 
 		auto function = std::make_shared<ASTFunction>(StringRange{begin, pos});
 		function->name = "transform";
-		function->genus = ASTFunction::Genus::CASE_WITH_EXPR;
 		function->arguments = function_args;
 		function->children.push_back(function->arguments);
 
@@ -148,7 +145,6 @@ bool ParserCase::parseImpl(Pos & pos, Pos end, ASTPtr & node, Pos & max_parsed_p
 
 		auto function = std::make_shared<ASTFunction>(StringRange{begin, pos});
 		function->name = "multiIf";
-		function->genus = ASTFunction::Genus::CASE_WITHOUT_EXPR;
 		function->arguments = function_args;
 		function->children.push_back(function->arguments);