tests: Unify TestCompactionHash and extend it to also Delete keys and Defrag

Signed-off-by: Marek Siarkowicz <siarkowicz@google.com>

server/storage/mvcc/testutil/hash.go

@@ -0,0 +1,105 @@
+// Copyright 2022 The etcd Authors
+//
+// 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 testutil
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+const (
+	// CompactionCycle is high prime used to test hash calculation between compactions.
+	CompactionCycle = 71
+)
+
+func TestCompactionHash(ctx context.Context, t *testing.T, h CompactionHashTestCase, compactionBatchLimit int) {
+	var totalRevisions int64 = 1210
+	assert.Less(t, int64(compactionBatchLimit), totalRevisions)
+	assert.Less(t, int64(CompactionCycle*10), totalRevisions)
+	var rev int64
+	for ; rev < totalRevisions; rev += CompactionCycle {
+		testCompactionHash(ctx, t, h, rev, rev+CompactionCycle)
+	}
+	testCompactionHash(ctx, t, h, rev, rev+totalRevisions)
+}
+
+type CompactionHashTestCase interface {
+	Put(ctx context.Context, key, value string) error
+	Delete(ctx context.Context, key string) error
+	HashByRev(ctx context.Context, rev int64) (KeyValueHash, error)
+	Defrag(ctx context.Context) error
+	Compact(ctx context.Context, rev int64) error
+}
+
+type KeyValueHash struct {
+	Hash            uint32
+	CompactRevision int64
+	Revision        int64
+}
+
+func testCompactionHash(ctx context.Context, t *testing.T, h CompactionHashTestCase, start, stop int64) {
+	for i := start; i <= stop; i++ {
+		if i%67 == 0 {
+			err := h.Delete(ctx, PickKey(i+83))
+			assert.NoError(t, err, "error on delete")
+		} else {
+			err := h.Put(ctx, PickKey(i), fmt.Sprint(i))
+			assert.NoError(t, err, "error on put")
+		}
+	}
+	hash1, err := h.HashByRev(ctx, stop)
+	assert.NoError(t, err, "error on hash (rev %v)", stop)
+
+	err = h.Compact(ctx, stop)
+	assert.NoError(t, err, "error on compact (rev %v)", stop)
+
+	err = h.Defrag(ctx)
+	assert.NoError(t, err, "error on defrag")
+
+	hash2, err := h.HashByRev(ctx, stop)
+	assert.NoError(t, err, "error on hash (rev %v)", stop)
+	assert.Equal(t, hash1, hash2, "hashes do not match on rev %v", stop)
+}
+
+func PickKey(i int64) string {
+	if i%(CompactionCycle*2) == 30 {
+		return "zenek"
+	}
+	if i%CompactionCycle == 30 {
+		return "xavery"
+	}
+	// Use low prime number to ensure repeats without alignment
+	switch i % 7 {
+	case 0:
+		return "alice"
+	case 1:
+		return "bob"
+	case 2:
+		return "celine"
+	case 3:
+		return "dominik"
+	case 4:
+		return "eve"
+	case 5:
+		return "frederica"
+	case 6:
+		return "gorge"
+	default:
+		panic("Can't count")
+	}
+}