Fix #2393 (#2395)

Reviewed-on: https://gitea.com/xorm/xorm/pulls/2395

session_iterate.go

@@ -27,6 +27,12 @@ func (session *Session) Iterate(bean interface{}, fun IterFunc) error {
 		defer session.Close()
 	}
 
+	session.autoResetStatement = false
+	defer func() {
+		session.autoResetStatement = true
+		session.resetStatement()
+	}()
+
 	if session.statement.LastError != nil {
 		return session.statement.LastError
 	}
@@ -64,15 +70,15 @@ func (session *Session) BufferSize(size int) *Session {
 }
 
 func (session *Session) bufferIterate(bean interface{}, fun IterFunc) error {
-	var bufferSize = session.statement.BufferSize
+	bufferSize := session.statement.BufferSize
-	var pLimitN = session.statement.LimitN
+	pLimitN := session.statement.LimitN
 	if pLimitN != nil && bufferSize > *pLimitN {
 		bufferSize = *pLimitN
 	}
-	var start = session.statement.Start
+	start := session.statement.Start
 	v := utils.ReflectValue(bean)
 	sliceType := reflect.SliceOf(v.Type())
-	var idx = 0
+	idx := 0
 	session.autoResetStatement = false
 	defer func() {
 		session.autoResetStatement = true

tests/session_iterate_test.go

@@ -111,4 +111,25 @@ func TestBufferIterate(t *testing.T) {
 	})
 	assert.NoError(t, err)
 	assert.EqualValues(t, 10, cnt)
+
+	// test reset statement
+	cnt = 0
+	sess := testEngine.NewSession()
+	defer sess.Close()
+	// generate: SELECT `id`, `is_man` FROM `user_buffer_iterate` WHERE (`id` <= 10) LIMIT 2 OFFSET 10 []
+	err = sess.Where("`id` <= 10").BufferSize(2).Iterate(new(UserBufferIterate), func(i int, bean interface{}) error {
+		user := bean.(*UserBufferIterate)
+		assert.EqualValues(t, cnt+1, user.Id)
+		assert.EqualValues(t, true, user.IsMan)
+		cnt++
+		return nil
+	})
+	assert.NoError(t, err)
+	assert.EqualValues(t, 10, cnt)
+
+	beans := make([]*UserBufferIterate, 0, 10)
+	// generate: SELECT `id`, `is_man` FROM `user_buffer_iterate` WHERE (`id` <= 10) AND (`id` >= 10) LIMIT 2 OFFSET 10 []
+	err = sess.Where("`id` >= 10").Limit(2).Find(&beans)
+	assert.NoError(t, err)
+	assert.Len(t, beans, 2)
 }