feat(collections): IndexedMap

collections/CHANGELOG.md

@@ -35,4 +35,5 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * [#14351](https://github.com/cosmos/cosmos-sdk/pull/14351) Add keyset
 * [#14364](https://github.com/cosmos/cosmos-sdk/pull/14364) Add sequence
 * [#14468](https://github.com/cosmos/cosmos-sdk/pull/14468) Add Map.IterateRaw API.
-* [#14310](https://github.com/cosmos/cosmos-sdk/pull/14310) Add Pair keys 
+* [#14310](https://github.com/cosmos/cosmos-sdk/pull/14310) Add Pair keys 
+* [#14397](https://github.com/cosmos/cosmos-sdk/pull/14397) Add IndexedMap

collections/collections.go

@@ -10,6 +10,8 @@ var (
 	ErrNotFound = errors.New("collections: not found")
 	// ErrEncoding is returned when something fails during key or value encoding/decoding.
 	ErrEncoding = errors.New("collections: encoding error")
+	// ErrConflict is returned when there are conflicts, for example in UniqueIndex.
+	ErrConflict = errors.New("collections: conflict")
 )
 
 // collection is the interface that all collections support. It will eventually

collections/collections_test.go

@@ -29,7 +29,6 @@ func (t testStore) Has(key []byte) (bool, error) {
 
 func (t testStore) Set(key, value []byte) error {
 	return t.db.Set(key, value)
-
 }
 
 func (t testStore) Delete(key []byte) error {

collections/colltest/codec.go

@@ -1,9 +1,14 @@
 package colltest
 
 import (
+	"encoding/json"
+	"fmt"
+	"reflect"
+	"testing"
+
 	"cosmossdk.io/collections"
+
 	"github.com/stretchr/testify/require"
-	"testing"
 )
 
 // TestKeyCodec asserts the correct behaviour of a KeyCodec over the type T.
@@ -21,6 +26,7 @@ func TestKeyCodec[T any](t *testing.T, keyCodec collections.KeyCodec[T], key T)
 	pairKey := collections.Join(key, "TEST")
 	buffer = make([]byte, pairCodec.Size(pairKey))
 	written, err = pairCodec.Encode(buffer, pairKey)
+	require.Equal(t, len(buffer), written, "the pair buffer should have been fully written")
 	require.NoError(t, err)
 	read, decodedPairKey, err := pairCodec.Decode(buffer)
 	require.NoError(t, err)
@@ -53,3 +59,101 @@ func TestValueCodec[T any](t *testing.T, encoder collections.ValueCodec[T], valu
 
 	_ = encoder.Stringify(value)
 }
+
+// MockValueCodec returns a mock of collections.ValueCodec for type T, it
+// can be used for collections Values testing. It also supports interfaces.
+// For the interfaces cases, in order for an interface to be decoded it must
+// have been encoded first. Not concurrency safe.
+// EG:
+// Let's say the value is interface Animal
+// if I want to decode Dog which implements Animal, then I need to first encode
+// it in order to make the type known by the MockValueCodec.
+func MockValueCodec[T any]() collections.ValueCodec[T] {
+	typ := reflect.ValueOf(new(T)).Elem().Type()
+	isInterface := false
+	if typ.Kind() == reflect.Interface {
+		isInterface = true
+	}
+	return &mockValueCodec[T]{
+		isInterface: isInterface,
+		seenTypes:   map[string]reflect.Type{},
+		valueType:   fmt.Sprintf("%s.%s", typ.PkgPath(), typ.Name()),
+	}
+}
+
+type mockValueJSON struct {
+	TypeName string          `json:"type_name"`
+	Value    json.RawMessage `json:"value"`
+}
+
+type mockValueCodec[T any] struct {
+	isInterface bool
+	seenTypes   map[string]reflect.Type
+	valueType   string
+}
+
+func (m mockValueCodec[T]) Encode(value T) ([]byte, error) {
+	typeName := m.getTypeName(value)
+	valueBytes, err := json.Marshal(value)
+	if err != nil {
+		return nil, err
+	}
+
+	return json.Marshal(mockValueJSON{
+		TypeName: typeName,
+		Value:    valueBytes,
+	})
+}
+
+func (m mockValueCodec[T]) Decode(b []byte) (t T, err error) {
+	wrappedValue := mockValueJSON{}
+	err = json.Unmarshal(b, &wrappedValue)
+	if err != nil {
+		return
+	}
+	if !m.isInterface {
+		err = json.Unmarshal(wrappedValue.Value, &t)
+		return t, err
+	}
+
+	typ, exists := m.seenTypes[wrappedValue.TypeName]
+	if !exists {
+		return t, fmt.Errorf("uknown type %s, you're dealing with interfaces... in order to make the interface types known for the MockValueCodec, you need to first encode them", wrappedValue.TypeName)
+	}
+
+	newT := reflect.New(typ).Interface()
+	err = json.Unmarshal(wrappedValue.Value, newT)
+	if err != nil {
+		return t, err
+	}
+
+	iface := new(T)
+	reflect.ValueOf(iface).Elem().Set(reflect.ValueOf(newT).Elem())
+	return *iface, nil
+}
+
+func (m mockValueCodec[T]) EncodeJSON(value T) ([]byte, error) {
+	return m.Encode(value)
+}
+
+func (m mockValueCodec[T]) DecodeJSON(b []byte) (T, error) {
+	return m.Decode(b)
+}
+
+func (m mockValueCodec[T]) Stringify(value T) string {
+	return fmt.Sprintf("%#v", value)
+}
+
+func (m mockValueCodec[T]) ValueType() string {
+	return m.valueType
+}
+
+func (m mockValueCodec[T]) getTypeName(value T) string {
+	if !m.isInterface {
+		return m.valueType
+	}
+	typ := reflect.TypeOf(value)
+	name := fmt.Sprintf("%s.%s", typ.PkgPath(), typ.Name())
+	m.seenTypes[name] = typ
+	return name
+}

collections/colltest/codec_test.go

@@ -0,0 +1,48 @@
+package colltest
+
+import "testing"
+
+type animal interface {
+	name() string
+}
+
+type dog struct {
+	Name        string `json:"name"`
+	BarksLoudly bool   `json:"barks_loudly"`
+}
+
+type cat struct {
+	Name      string `json:"name"`
+	Scratches bool   `json:"scratches"`
+}
+
+func (d *cat) name() string { return d.Name }
+
+func (d dog) name() string { return d.Name }
+
+func TestMockValueCodec(t *testing.T) {
+	t.Run("primitive type", func(t *testing.T) {
+		x := MockValueCodec[string]()
+		TestValueCodec(t, x, "hello")
+	})
+
+	t.Run("struct type", func(t *testing.T) {
+		x := MockValueCodec[dog]()
+		TestValueCodec(t, x, dog{
+			Name:        "kernel",
+			BarksLoudly: true,
+		})
+	})
+
+	t.Run("interface type", func(t *testing.T) {
+		x := MockValueCodec[animal]()
+		TestValueCodec[animal](t, x, dog{
+			Name:        "kernel",
+			BarksLoudly: true,
+		})
+		TestValueCodec[animal](t, x, &cat{
+			Name:      "echo",
+			Scratches: true,
+		})
+	})
+}

collections/colltest/store.go

@@ -0,0 +1,49 @@
+package colltest
+
+import (
+	"context"
+
+	"cosmossdk.io/core/store"
+	db "github.com/cosmos/cosmos-db"
+)
+
+// MockStore returns a mock store.KVStoreService and a mock context.Context.
+// They can be used to test collections.
+func MockStore() (store.KVStoreService, context.Context) {
+	kv := db.NewMemDB()
+	return &testStore{kv}, context.Background()
+}
+
+type testStore struct {
+	db db.DB
+}
+
+func (t testStore) OpenKVStore(ctx context.Context) store.KVStore {
+	return t
+}
+
+func (t testStore) Get(key []byte) ([]byte, error) {
+	return t.db.Get(key)
+}
+
+func (t testStore) Has(key []byte) (bool, error) {
+	return t.db.Has(key)
+}
+
+func (t testStore) Set(key, value []byte) error {
+	return t.db.Set(key, value)
+}
+
+func (t testStore) Delete(key []byte) error {
+	return t.db.Delete(key)
+}
+
+func (t testStore) Iterator(start, end []byte) (store.Iterator, error) {
+	return t.db.Iterator(start, end)
+}
+
+func (t testStore) ReverseIterator(start, end []byte) (store.Iterator, error) {
+	return t.db.ReverseIterator(start, end)
+}
+
+var _ store.KVStore = testStore{}

collections/correctness_test.go

@@ -1,9 +1,10 @@
 package collections_test
 
 import (
+	"testing"
+
 	"cosmossdk.io/collections"
 	"cosmossdk.io/collections/colltest"
-	"testing"
 )
 
 func TestKeyCorrectness(t *testing.T) {

collections/genesis.go

@@ -20,13 +20,13 @@ type jsonMapEntry struct {
 }
 
 func (m Map[K, V]) validateGenesis(reader io.Reader) error {
-	return m.doDecodeJson(reader, func(key K, value V) error {
+	return m.doDecodeJSON(reader, func(key K, value V) error {
 		return nil
 	})
 }
 
 func (m Map[K, V]) importGenesis(ctx context.Context, reader io.Reader) error {
-	return m.doDecodeJson(reader, func(key K, value V) error {
+	return m.doDecodeJSON(reader, func(key K, value V) error {
 		return m.Set(ctx, key, value)
 	})
 }
@@ -95,7 +95,7 @@ func (m Map[K, V]) exportGenesis(ctx context.Context, writer io.Writer) error {
 	return err
 }
 
-func (m Map[K, V]) doDecodeJson(reader io.Reader, onEntry func(key K, value V) error) error {
+func (m Map[K, V]) doDecodeJSON(reader io.Reader, onEntry func(key K, value V) error) error {
 	decoder := json.NewDecoder(reader)
 	token, err := decoder.Token()
 	if err != nil {
@@ -107,14 +107,14 @@ func (m Map[K, V]) doDecodeJson(reader io.Reader, onEntry func(key K, value V) e
 	}
 
 	for decoder.More() {
-		var rawJson json.RawMessage
-		err := decoder.Decode(&rawJson)
+		var rawJSON json.RawMessage
+		err := decoder.Decode(&rawJSON)
 		if err != nil {
 			return err
 		}
 
 		var mapEntry jsonMapEntry
-		err = json.Unmarshal(rawJson, &mapEntry)
+		err = json.Unmarshal(rawJSON, &mapEntry)
 		if err != nil {
 			return err
 		}