leveldb/testutil/iter.go
// Copyright © 2014, Suryandaru Triandana <syndtr@gmail.com>
// Copyright © 2021, Jeffrey H. Johnson <trnsz@pobox.com>
//
// All rights reserved.
//
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
package testutil
import (
"fmt"
"math/rand"
. "github.com/onsi/gomega"
"github.com/johnsonjh/jleveldb/leveldb/iterator"
)
type IterAct int
func (a IterAct) String() string {
switch a {
case IterNone:
return "none"
case IterFirst:
return "first"
case IterLast:
return "last"
case IterPrev:
return "prev"
case IterNext:
return "next"
case IterSeek:
return "seek"
case IterSOI:
return "soi"
case IterEOI:
return "eoi"
}
return "unknown"
}
const (
IterNone IterAct = iota
IterFirst
IterLast
IterPrev
IterNext
IterSeek
IterSOI
IterEOI
)
type IteratorTesting struct {
KeyValue
Iter iterator.Iterator
Rand *rand.Rand
PostFn func(t *IteratorTesting)
Pos int
Act, LastAct IterAct
once bool
}
func (t *IteratorTesting) init() {
if !t.once {
t.Pos = -1
t.once = true
}
}
func (t *IteratorTesting) post() {
if t.PostFn != nil {
t.PostFn(t)
}
}
func (t *IteratorTesting) setAct(act IterAct) {
t.LastAct, t.Act = t.Act, act
}
func (t *IteratorTesting) text() string {
return fmt.Sprintf("at pos %d and last action was <%v> -> <%v>", t.Pos, t.LastAct, t.Act)
}
func (t *IteratorTesting) Text() string {
return "IteratorTesting is " + t.text()
}
func (t *IteratorTesting) IsFirst() bool {
t.init()
return t.Len() > 0 && t.Pos == 0
}
func (t *IteratorTesting) IsLast() bool {
t.init()
return t.Len() > 0 && t.Pos == t.Len()-1
}
func (t *IteratorTesting) TestKV() {
t.init()
key, value := t.Index(t.Pos)
Expect(t.Iter.Key()).NotTo(BeNil())
Expect(t.Iter.Key()).Should(Equal(key), "Key is invalid, %s", t.text())
Expect(t.Iter.Value()).Should(Equal(value), "Value for key %q, %s", key, t.text())
}
func (t *IteratorTesting) First() {
t.init()
t.setAct(IterFirst)
ok := t.Iter.First()
Expect(t.Iter.Error()).ShouldNot(HaveOccurred())
if t.Len() > 0 {
t.Pos = 0
Expect(ok).Should(BeTrue(), t.Text())
t.TestKV()
} else {
t.Pos = -1
Expect(ok).ShouldNot(BeTrue(), t.Text())
}
t.post()
}
func (t *IteratorTesting) Last() {
t.init()
t.setAct(IterLast)
ok := t.Iter.Last()
Expect(t.Iter.Error()).ShouldNot(HaveOccurred())
if t.Len() > 0 {
t.Pos = t.Len() - 1
Expect(ok).Should(BeTrue(), t.Text())
t.TestKV()
} else {
t.Pos = 0
Expect(ok).ShouldNot(BeTrue(), t.Text())
}
t.post()
}
func (t *IteratorTesting) Next() {
t.init()
t.setAct(IterNext)
ok := t.Iter.Next()
Expect(t.Iter.Error()).ShouldNot(HaveOccurred())
if t.Pos < t.Len()-1 {
t.Pos++
Expect(ok).Should(BeTrue(), t.Text())
t.TestKV()
} else {
t.Pos = t.Len()
Expect(ok).ShouldNot(BeTrue(), t.Text())
}
t.post()
}
func (t *IteratorTesting) Prev() {
t.init()
t.setAct(IterPrev)
ok := t.Iter.Prev()
Expect(t.Iter.Error()).ShouldNot(HaveOccurred())
if t.Pos > 0 {
t.Pos--
Expect(ok).Should(BeTrue(), t.Text())
t.TestKV()
} else {
t.Pos = -1
Expect(ok).ShouldNot(BeTrue(), t.Text())
}
t.post()
}
func (t *IteratorTesting) Seek(i int) {
t.init()
t.setAct(IterSeek)
key, _ := t.Index(i)
oldKey, _ := t.IndexOrNil(t.Pos)
ok := t.Iter.Seek(key)
Expect(t.Iter.Error()).ShouldNot(HaveOccurred())
Expect(ok).Should(BeTrue(), fmt.Sprintf("Seek from key %q to %q, to pos %d, %s", oldKey, key, i, t.text()))
t.Pos = i
t.TestKV()
t.post()
}
func (t *IteratorTesting) SeekInexact(i int) {
t.init()
t.setAct(IterSeek)
var key0 []byte
key1, _ := t.Index(i)
if i > 0 {
key0, _ = t.Index(i - 1)
}
key := BytesSeparator(key0, key1)
oldKey, _ := t.IndexOrNil(t.Pos)
ok := t.Iter.Seek(key)
Expect(t.Iter.Error()).ShouldNot(HaveOccurred())
Expect(ok).Should(BeTrue(), fmt.Sprintf("Seek from key %q to %q (%q), to pos %d, %s", oldKey, key, key1, i, t.text()))
t.Pos = i
t.TestKV()
t.post()
}
func (t *IteratorTesting) SeekKey(key []byte) {
t.init()
t.setAct(IterSeek)
oldKey, _ := t.IndexOrNil(t.Pos)
i := t.Search(key)
ok := t.Iter.Seek(key)
Expect(t.Iter.Error()).ShouldNot(HaveOccurred())
if i < t.Len() {
key_, _ := t.Index(i)
Expect(ok).Should(BeTrue(), fmt.Sprintf("Seek from key %q to %q (%q), to pos %d, %s", oldKey, key, key_, i, t.text()))
t.Pos = i
t.TestKV()
} else {
Expect(ok).ShouldNot(BeTrue(), fmt.Sprintf("Seek from key %q to %q, %s", oldKey, key, t.text()))
}
t.Pos = i
t.post()
}
func (t *IteratorTesting) SOI() {
t.init()
t.setAct(IterSOI)
Expect(t.Pos).Should(BeNumerically("<=", 0), t.Text())
for i := 0; i < 3; i++ {
t.Prev()
}
t.post()
}
func (t *IteratorTesting) EOI() {
t.init()
t.setAct(IterEOI)
Expect(t.Pos).Should(BeNumerically(">=", t.Len()-1), t.Text())
for i := 0; i < 3; i++ {
t.Next()
}
t.post()
}
func (t *IteratorTesting) WalkPrev(fn func(t *IteratorTesting)) {
t.init()
for old := t.Pos; t.Pos > 0; old = t.Pos {
fn(t)
Expect(t.Pos).Should(BeNumerically("<", old), t.Text())
}
}
func (t *IteratorTesting) WalkNext(fn func(t *IteratorTesting)) {
t.init()
for old := t.Pos; t.Pos < t.Len()-1; old = t.Pos {
fn(t)
Expect(t.Pos).Should(BeNumerically(">", old), t.Text())
}
}
func (t *IteratorTesting) PrevAll() {
t.WalkPrev(func(t *IteratorTesting) {
t.Prev()
})
}
func (t *IteratorTesting) NextAll() {
t.WalkNext(func(t *IteratorTesting) {
t.Next()
})
}
func DoIteratorTesting(t *IteratorTesting) {
if t.Rand == nil {
t.Rand = NewRand()
}
t.SOI()
t.NextAll()
t.First()
t.SOI()
t.NextAll()
t.EOI()
t.PrevAll()
t.Last()
t.EOI()
t.PrevAll()
t.SOI()
t.NextAll()
t.PrevAll()
t.NextAll()
t.Last()
t.PrevAll()
t.First()
t.NextAll()
t.EOI()
ShuffledIndex(t.Rand, t.Len(), 1, func(i int) {
t.Seek(i)
})
ShuffledIndex(t.Rand, t.Len(), 1, func(i int) {
t.SeekInexact(i)
})
ShuffledIndex(t.Rand, t.Len(), 1, func(i int) {
t.Seek(i)
if i%2 != 0 {
t.PrevAll()
t.SOI()
} else {
t.NextAll()
t.EOI()
}
})
for _, key := range []string{"", "foo", "bar", "\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff"} {
t.SeekKey([]byte(key))
}
}