From 1a28c4b89c3235d4cdf4e060c23f88b19dd99e6b Mon Sep 17 00:00:00 2001
From: Ethan Buchman <ethan@coinculture.info>
Date: Tue, 12 Dec 2017 02:36:50 -0500
Subject: [PATCH] store: add some tests, fix deadlocks (#297)

---
 store/iavlstore.go      |  44 ++++++++----------
 store/iavlstore_test.go | 100 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 120 insertions(+), 24 deletions(-)
 create mode 100644 store/iavlstore_test.go

diff --git a/store/iavlstore.go b/store/iavlstore.go
index a90941462670..bd1cc22fd980 100644
--- a/store/iavlstore.go
+++ b/store/iavlstore.go
@@ -7,6 +7,13 @@ import (
 	dbm "github.com/tendermint/tmlibs/db"
 )
 
+// iavlStoreLoader contains info on what store we want to load from
+type iavlStoreLoader struct {
+	db         dbm.DB
+	cacheSize  int
+	numHistory int64
+}
+
 // NewIAVLStoreLoader returns a CommitStoreLoader that returns an iavlStore
 func NewIAVLStoreLoader(db dbm.DB, cacheSize int, numHistory int64) CommitStoreLoader {
 	l := iavlStoreLoader{
@@ -17,6 +24,19 @@ func NewIAVLStoreLoader(db dbm.DB, cacheSize int, numHistory int64) CommitStoreL
 	return l.Load
 }
 
+// Load implements CommitLoader.
+func (isl iavlStoreLoader) Load(id CommitID) (CommitStore, error) {
+	tree := iavl.NewVersionedTree(isl.db, isl.cacheSize)
+	err := tree.Load()
+	if err != nil {
+		return nil, err
+	}
+	store := newIAVLStore(tree, isl.numHistory)
+	return store, nil
+}
+
+//----------------------------------------
+
 var _ IterKVStore = (*iavlStore)(nil)
 var _ CommitStore = (*iavlStore)(nil)
 
@@ -243,8 +263,6 @@ func (iter *iavlIterator) Release() {
 //----------------------------------------
 
 func (iter *iavlIterator) setNext(key, value []byte) {
-	iter.mtx.Lock()
-	defer iter.mtx.Unlock()
 	iter.assertIsValid()
 
 	iter.key = key
@@ -252,8 +270,6 @@ func (iter *iavlIterator) setNext(key, value []byte) {
 }
 
 func (iter *iavlIterator) setInvalid() {
-	iter.mtx.Lock()
-	defer iter.mtx.Unlock()
 	iter.assertIsValid()
 
 	iter.invalid = true
@@ -280,26 +296,6 @@ func (iter *iavlIterator) assertIsValid() {
 
 //----------------------------------------
 
-// iavlStoreLoader contains info on what store we want to load from
-type iavlStoreLoader struct {
-	db         dbm.DB
-	cacheSize  int
-	numHistory int64
-}
-
-// Load implements CommitLoader.
-func (isl iavlStoreLoader) Load(id CommitID) (CommitStore, error) {
-	tree := iavl.NewVersionedTree(isl.db, isl.cacheSize)
-	err := tree.Load()
-	if err != nil {
-		return nil, err
-	}
-	store := newIAVLStore(tree, isl.numHistory)
-	return store, nil
-}
-
-//----------------------------------------
-
 func cp(bz []byte) (ret []byte) {
 	ret = make([]byte, len(bz))
 	copy(ret, bz)
diff --git a/store/iavlstore_test.go b/store/iavlstore_test.go
new file mode 100644
index 000000000000..5ed1a1a29f06
--- /dev/null
+++ b/store/iavlstore_test.go
@@ -0,0 +1,100 @@
+package store
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+
+	cmn "github.com/tendermint/tmlibs/common"
+	dbm "github.com/tendermint/tmlibs/db"
+
+	"github.com/tendermint/iavl"
+)
+
+var (
+	cacheSize        = 100
+	numHistory int64 = 5
+)
+
+var (
+	treeData = map[string]string{
+		"hello": "goodbye",
+		"aloha": "shalom",
+	}
+	nMoreData = 0
+)
+
+// make a tree and save it
+func newTree(t *testing.T, db dbm.DB) (*iavl.VersionedTree, CommitID) {
+	tree := iavl.NewVersionedTree(db, cacheSize)
+	for k, v := range treeData {
+		tree.Set([]byte(k), []byte(v))
+	}
+	for i := 0; i < nMoreData; i++ {
+		key := cmn.RandBytes(12)
+		value := cmn.RandBytes(50)
+		tree.Set(key, value)
+	}
+	hash, ver, err := tree.SaveVersion()
+	assert.Nil(t, err)
+	return tree, CommitID{ver, hash}
+}
+
+func TestIAVLStoreLoader(t *testing.T) {
+	db := dbm.NewMemDB()
+	_, id := newTree(t, db)
+
+	iavlLoader := NewIAVLStoreLoader(db, cacheSize, numHistory)
+	commitStore, err := iavlLoader(id)
+	assert.Nil(t, err)
+
+	id2 := commitStore.Commit()
+
+	assert.Equal(t, id.Hash, id2.Hash)
+	assert.Equal(t, id.Version+1, id2.Version)
+}
+
+func TestIAVLStoreGetSetHasRemove(t *testing.T) {
+	db := dbm.NewMemDB()
+	tree, _ := newTree(t, db)
+	iavlStore := newIAVLStore(tree, numHistory)
+
+	key := "hello"
+
+	exists := iavlStore.Has([]byte(key))
+	assert.True(t, exists)
+
+	value, exists := iavlStore.Get([]byte(key))
+	assert.True(t, exists)
+	assert.EqualValues(t, value, treeData[key])
+
+	value2 := "notgoodbye"
+	prev := iavlStore.Set([]byte(key), []byte(value2))
+	assert.EqualValues(t, value, prev)
+
+	value, exists = iavlStore.Get([]byte(key))
+	assert.True(t, exists)
+	assert.EqualValues(t, value, value2)
+
+	prev, removed := iavlStore.Remove([]byte(key))
+	assert.True(t, removed)
+	assert.EqualValues(t, value2, prev)
+
+	exists = iavlStore.Has([]byte(key))
+	assert.False(t, exists)
+}
+
+func TestIAVLIterator(t *testing.T) {
+	db := dbm.NewMemDB()
+	tree, _ := newTree(t, db)
+	iavlStore := newIAVLStore(tree, numHistory)
+	iter := iavlStore.Iterator([]byte("aloha"), []byte("hellz"))
+	expected := []string{"aloha", "hello"}
+	for i := 0; iter.Valid(); iter.Next() {
+		expectedKey := expected[i]
+		key, value := iter.Key(), iter.Value()
+		assert.EqualValues(t, key, expectedKey)
+		assert.EqualValues(t, value, treeData[expectedKey])
+		i += 1
+	}
+}