Add lasterror on statement to return errors when chain operations

* add lasterror on statement to return errors when chain operations

* add tests for last error

* refactor error

error.go

@@ -32,6 +32,8 @@ var (
 	ErrConditionType = errors.New("Unsupported condition type")
 	// ErrNeedMoreArguments need more arguments
 	ErrNeedMoreArguments = errors.New("Need more sql arguments")
+	// ErrUnSupportedSQLType parameter of SQL is not supported
+	ErrUnSupportedSQLType = errors.New("unsupported sql type")
 )
 
 // ErrFieldIsNotExist columns does not exist

session_delete.go

@@ -79,6 +79,10 @@ func (session *Session) Delete(bean interface{}) (int64, error) {
 		defer session.Close()
 	}
 
+	if session.statement.lastError != nil {
+		return 0, session.statement.lastError
+	}
+
 	if err := session.statement.setRefBean(bean); err != nil {
 		return 0, err
 	}

session_exist.go

@@ -19,6 +19,10 @@ func (session *Session) Exist(bean ...interface{}) (bool, error) {
 		defer session.Close()
 	}
 
+	if session.statement.lastError != nil {
+		return false, session.statement.lastError
+	}
+
 	var sqlStr string
 	var args []interface{}
 	var err error

session_find.go

@@ -84,6 +84,10 @@ func (session *Session) FindAndCount(rowsSlicePtr interface{}, condiBean ...inte
 }
 
 func (session *Session) find(rowsSlicePtr interface{}, condiBean ...interface{}) error {
+	if session.statement.lastError != nil {
+		return session.statement.lastError
+	}
+
 	sliceValue := reflect.Indirect(reflect.ValueOf(rowsSlicePtr))
 	if sliceValue.Kind() != reflect.Slice && sliceValue.Kind() != reflect.Map {
 		return errors.New("needs a pointer to a slice or a map")

session_get.go

@@ -24,6 +24,10 @@ func (session *Session) Get(bean interface{}) (bool, error) {
 }
 
 func (session *Session) get(bean interface{}) (bool, error) {
+	if session.statement.lastError != nil {
+		return false, session.statement.lastError
+	}
+
 	beanValue := reflect.ValueOf(bean)
 	if beanValue.Kind() != reflect.Ptr {
 		return false, errors.New("needs a pointer to a value")

session_iterate.go

@@ -23,6 +23,10 @@ func (session *Session) Iterate(bean interface{}, fun IterFunc) error {
 		defer session.Close()
 	}
 
+	if session.statement.lastError != nil {
+		return session.statement.lastError
+	}
+
 	if session.statement.bufferSize > 0 {
 		return session.bufferIterate(bean, fun)
 	}

session_update.go

@@ -147,6 +147,10 @@ func (session *Session) Update(bean interface{}, condiBean ...interface{}) (int6
 		defer session.Close()
 	}
 
+	if session.statement.lastError != nil {
+		return 0, session.statement.lastError
+	}
+
 	v := rValue(bean)
 	t := v.Type()
 

session_update_test.go

@@ -1331,3 +1331,21 @@ func TestUpdateCondiBean(t *testing.T) {
 	assert.NoError(t, err)
 	assert.True(t, has)
 }
+
+func TestWhereCondErrorWhenUpdate(t *testing.T) {
+	type AuthRequestError struct {
+		ChallengeToken string
+		RequestToken   string
+	}
+
+	assert.NoError(t, prepareEngine())
+	assertSync(t, new(AuthRequestError))
+
+	_, err := testEngine.Cols("challenge_token", "request_token", "challenge_agent", "status").
+		Where(&AuthRequestError{ChallengeToken: "1"}).
+		Update(&AuthRequestError{
+			ChallengeToken: "2",
+		})
+	assert.Error(t, err)
+	assert.EqualValues(t, ErrConditionType, err)
+}

statement.go

@@ -60,6 +60,7 @@ type Statement struct {
 	cond            builder.Cond
 	bufferSize      int
 	context         ContextCache
+	lastError       error
 }
 
 // Init reset all the statement's fields
@@ -101,6 +102,7 @@ func (statement *Statement) Init() {
 	statement.cond = builder.NewCond()
 	statement.bufferSize = 0
 	statement.context = nil
+	statement.lastError = nil
 }
 
 // NoAutoCondition if you do not want convert bean's field as query condition, then use this function
@@ -125,13 +127,13 @@ func (statement *Statement) SQL(query interface{}, args ...interface{}) *Stateme
 		var err error
 		statement.RawSQL, statement.RawParams, err = query.(*builder.Builder).ToSQL()
 		if err != nil {
-			statement.Engine.logger.Error(err)
+			statement.lastError = err
 		}
 	case string:
 		statement.RawSQL = query.(string)
 		statement.RawParams = args
 	default:
-		statement.Engine.logger.Error("unsupported sql type")
+		statement.lastError = ErrUnSupportedSQLType
 	}
 
 	return statement