Files
tidb/testkit/testfork/fork.go
2022-09-08 11:44:56 +08:00

139 lines
3.0 KiB
Go

// Copyright 2022 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 testfork
import (
"fmt"
"os"
"strings"
"testing"
"github.com/pingcap/errors"
"github.com/stretchr/testify/require"
)
type pickStack struct {
stack [][]any
pos int
valid bool
}
func newPickStack() *pickStack {
return &pickStack{
valid: true,
}
}
func (s *pickStack) NextStack() {
for len(s.stack) > 0 {
lastIndex := len(s.stack) - 1
s.stack[lastIndex] = s.stack[lastIndex][1:]
if len(s.stack[lastIndex]) > 0 {
break
}
s.stack = s.stack[:lastIndex]
}
s.pos = 0
s.valid = len(s.stack) > 0
}
func (s *pickStack) PickValue(values []any) (any, error) {
if len(values) == 0 {
return nil, errors.New("values should not be empty")
}
stackLen := len(s.stack)
if s.pos > stackLen {
return nil, errors.Errorf("illegal state %d > %d", s.pos, stackLen)
}
defer func() {
s.pos++
}()
if s.pos == stackLen {
s.stack = append(s.stack, values)
}
return s.stack[s.pos][0], nil
}
func (s *pickStack) Values() []any {
values := make([]any, 0)
for _, v := range s.stack {
values = append(values, v[0])
}
return values
}
func (s *pickStack) ValuesText() string {
values := s.Values()
strValues := make([]string, len(values))
for i, value := range values {
switch v := value.(type) {
case string:
strValues[i] = fmt.Sprintf(`"%s"`, v)
default:
strValues[i] = fmt.Sprintf("%v", v)
}
}
return "[" + strings.Join(strValues, " ") + "]"
}
func (s *pickStack) Valid() bool {
return s.valid
}
// T is used by for test
type T struct {
*testing.T
stack *pickStack
}
// RunTest runs the test function `f` multiple times util all the values in `Pick` are tested.
func RunTest(t *testing.T, f func(t *T)) {
idx := 0
runFunc := func(stack *pickStack, f func(t *T)) func(t *testing.T) {
return func(t *testing.T) {
f(&T{T: t, stack: stack})
}
}
for stack := newPickStack(); stack.Valid(); stack.NextStack() {
success := t.Run("", runFunc(stack, f))
if !success {
_, err := fmt.Fprintf(os.Stderr, "SubTest #%v failed, failed values: %s\n", idx, stack.ValuesText())
require.NoError(t, err)
}
idx++
}
}
// Pick returns a value from the values list
func Pick[E any](t *T, values []E) E {
slice := make([]any, len(values))
for i, item := range values {
slice[i] = item
}
value, err := t.stack.PickValue(slice)
require.NoError(t, err)
return value.(E)
}
// PickEnum returns a value from the value enums
func PickEnum[E any](t *T, item E, other ...E) E {
return Pick(t, append([]E{item}, other...))
}