tidb iter 代码
文件路径：/util/mock/iter.go
/ Copyright 2021 PingCAP, Inc.
/
/ Licensed under the Apache License, Version 2.0 (the "License");
/ you may not use this file except in compliance with the License.
/ You may obtain a copy of the License at
/
/ http://www.apache.org/licenses/LICENSE-2.0
/
/ Unless required by applicable law or agreed to in writing, software
/ distributed under the License is distributed on an "AS IS" BASIS,
/ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/ See the License for the specific language governing permissions and
/ limitations under the License.
package mock
import (
"testing"
"github.com/pingcap/errors"
"github.com/pingcap/tidb/kv"
"github.com/stretchr/testify/assert"
)
/ SliceIter is used to iterate slice
type SliceIter struct {
data []*kv.Entry
cur int
}
/ NewSliceIter creates a new SliceIter
func NewSliceIter(data []*kv.Entry) *SliceIter {
return &SliceIter{
data,
0,
}
}
/ GetSlice returns the inner slice
func (i *SliceIter) GetSlice() []*kv.Entry {
return i.data
}
/ Valid returns true if the current iterator is valid.
func (i *SliceIter) Valid() bool {
return i.cur >= 0 && i.cur < len(i.data)
}
/ Key returns the current key.
func (i *SliceIter) Key() kv.Key {
if !i.Valid() {
return nil
}
return i.data[i.cur].Key
}
/ Value returns the current value.
func (i *SliceIter) Value() []byte {
if !i.Valid() {
return nil
}
return i.data[i.cur].Value
}
/ Next goes the next position. Always return error for this iterator
func (i *SliceIter) Next() error {
if !i.Valid() {
return errors.New("iterator is invalid")
}
i.cur++
return nil
}
/ Close closes the iterator.
func (i *SliceIter) Close() {
i.cur = -1
}
/ MockedIter is a mocked iter for test
type MockedIter struct {
kv.Iterator
t *testing.T
nextErr error
closed bool
failOnMultiClose bool
}
/ NewMockIterFromRecords creates a new MockedIter
func NewMockIterFromRecords(t *testing.T, records []*kv.Entry, failOnMultiClose bool) *MockedIter {
return &MockedIter{
t: t,
Iterator: NewSliceIter(records),
failOnMultiClose: failOnMultiClose,
}
}
/ InjectNextError injects error to its Next
func (i *MockedIter) InjectNextError(err error) {
i.nextErr = err
}
/ GetInjectedNextError get the injected error
func (i *MockedIter) GetInjectedNextError() error {
return i.nextErr
}
/ FailOnMultiClose set if should fail when Close is invoked more than once
func (i *MockedIter) FailOnMultiClose(fail bool) {
i.failOnMultiClose = fail
}
/ Next implements kv.Iterator.Next
func (i *MockedIter) Next() error {
if i.nextErr != nil {
return i.nextErr
}
return i.Iterator.Next()
}
/ Close implements kv.Iterator.Close
func (i *MockedIter) Close() {
if i.closed && i.failOnMultiClose {
assert.FailNow(i.t, "Multi close iter")
}
i.closed = true
i.Iterator.Close()
}
/ Closed returns if the iter is closed
func (i *MockedIter) Closed() bool {
return i.closed
}