undo the initvalue and setvalue changes

Author: jennifersp

sql/base_session.go

@@ -167,7 +167,7 @@ func (s *BaseSession) InitSessionVariableDefault(ctx *Context, sysVarName string
 	}
 
 	sysVar.SetDefault(value)
-	svv, err := sysVar.InitValue(ctx, sysVar.GetDefault(), value, false)
+	svv, err := sysVar.InitValue(ctx, value, false)
 	if err != nil {
 		return err
 	}
@@ -180,25 +180,21 @@ func (s *BaseSession) InitSessionVariableDefault(ctx *Context, sysVarName string
 	return nil
 }
 
-func (s *BaseSession) setSessVar(ctx *Context, sysVar SystemVariable, newVal interface{}, init bool) error {
+func (s *BaseSession) setSessVar(ctx *Context, sysVar SystemVariable, val interface{}, init bool) error {
 	var svv SystemVarValue
 	var err error
-	sysVarName := strings.ToLower(sysVar.GetName())
-	var currVal = sysVar.GetDefault()
-	if ov, ok := s.systemVars[sysVarName]; ok {
-		currVal = ov.Val
-	}
 	if init {
-		svv, err = sysVar.InitValue(ctx, currVal, newVal, false)
+		svv, err = sysVar.InitValue(ctx, val, false)
 		if err != nil {
 			return err
 		}
 	} else {
-		svv, err = sysVar.SetValue(ctx, currVal, newVal, false)
+		svv, err = sysVar.SetValue(ctx, val, false)
 		if err != nil {
 			return err
 		}
 	}
+	sysVarName := strings.ToLower(sysVar.GetName())
 	s.systemVars[sysVarName] = svv
 	if sysVarName == characterSetResultsSysVarName {
 		s.charset = CharacterSet_Unspecified

sql/core.go

@@ -547,12 +547,12 @@ type SystemVariable interface {
 	// InitValue sets value without validation.
 	// This is used for setting the initial values internally
 	// using pre-defined variables or for test-purposes.
-	InitValue(ctx *Context, currVal, newVal any, global bool) (SystemVarValue, error)
+	InitValue(ctx *Context, val any, global bool) (SystemVarValue, error)
 	// SetValue sets the value of the sv of given scope, global or session
 	// It validates setting value of correct scope,
 	// converts the given value to appropriate value depending on the sv
 	// and it returns the SystemVarValue with the updated value.
-	SetValue(ctx *Context, currVal, newVal any, global bool) (SystemVarValue, error)
+	SetValue(ctx *Context, val any, global bool) (SystemVarValue, error)
 	// IsReadOnly checks whether the variable is read only.
 	// It returns false if variable can be set to a value.
 	IsReadOnly() bool
@@ -626,8 +626,8 @@ func (m *MysqlSystemVariable) GetDefault() any {
 }
 
 // InitValue implements SystemVariable.
-func (m *MysqlSystemVariable) InitValue(ctx *Context, currVal, newVal any, global bool) (SystemVarValue, error) {
-	convertedVal, _, err := m.Type.Convert(ctx, newVal)
+func (m *MysqlSystemVariable) InitValue(ctx *Context, val any, global bool) (SystemVarValue, error) {
+	convertedVal, _, err := m.Type.Convert(ctx, val)
 	if err != nil {
 		return SystemVarValue{}, err
 	}
@@ -649,7 +649,7 @@ func (m *MysqlSystemVariable) InitValue(ctx *Context, currVal, newVal any, globa
 }
 
 // SetValue implements SystemVariable.
-func (m *MysqlSystemVariable) SetValue(ctx *Context, currVal, newVal any, global bool) (SystemVarValue, error) {
+func (m *MysqlSystemVariable) SetValue(ctx *Context, val any, global bool) (SystemVarValue, error) {
 	if global && m.Scope.Type == SystemVariableScope_Session {
 		return SystemVarValue{}, ErrSystemVariableSessionOnly.New(m.Name)
 	}
@@ -659,7 +659,7 @@ func (m *MysqlSystemVariable) SetValue(ctx *Context, currVal, newVal any, global
 	if !m.Dynamic || m.ValueFunction != nil {
 		return SystemVarValue{}, ErrSystemVariableReadOnly.New(m.Name)
 	}
-	return m.InitValue(ctx, currVal, newVal, global)
+	return m.InitValue(ctx, val, global)
 }
 
 // IsReadOnly implements SystemVariable.

sql/variables/system_variables.go

@@ -78,7 +78,7 @@ func (sv *globalSystemVariables) AssignValues(vals map[string]interface{}) error
 		if !ok {
 			return sql.ErrUnknownSystemVariable.New(varName)
 		}
-		svv, err := sysVar.InitValue(ctx, sysVar.GetDefault(), val, true)
+		svv, err := sysVar.InitValue(ctx, val, true)
 		if err != nil {
 			return err
 		}
@@ -137,19 +137,15 @@ func (sv *globalSystemVariables) GetGlobal(name string) (sql.SystemVariable, int
 // Only global dynamic variables may be set through this function, as it is intended for use through the SET GLOBAL
 // statement. To set session system variables, use the appropriate function on the session context. To set values
 // directly (such as when loading persisted values), use AssignValues. Case-insensitive.
-func (sv *globalSystemVariables) SetGlobal(ctx *sql.Context, name string, newVal interface{}) error {
+func (sv *globalSystemVariables) SetGlobal(ctx *sql.Context, name string, val interface{}) error {
 	sv.mutex.Lock()
 	defer sv.mutex.Unlock()
 	name = strings.ToLower(name)
 	sysVar, ok := systemVars[name]
 	if !ok {
 		return sql.ErrUnknownSystemVariable.New(name)
 	}
-	var currVal = sysVar.GetDefault()
-	if sysVarVal, exists := sv.sysVarVals[name]; exists {
-		currVal = sysVarVal.Val
-	}
-	svv, err := sysVar.SetValue(ctx, currVal, newVal, true)
+	svv, err := sysVar.SetValue(ctx, val, true)
 	if err != nil {
 		return err
 	}