requested changes

Makefile

@@ -97,6 +97,10 @@ benchmark_smst_ops:  ## runs the benchmarks test different operations on the SMS
 benchmark_proof_sizes:  ## runs the benchmarks test the proof sizes for different sized tries
 	go test -tags=benchmark -v ./benchmarks -run ProofSizes
 
+.PHONY: benchmark_pebble
+benchmark_pebble:  ## TODO: Add the pebble benchmarks
+	echo "TODO: Implement pebble benchmarks"
+
 ###########################
 ###   Release Helpers   ###
 ###########################
@@ -124,4 +128,4 @@ tag_minor_release: ## Tag a new minor release (e.g. v1.0.0 -> v1.1.0)
 	@echo "New minor release version tagged: $(NEW_TAG)"
 	@echo "Run the following commands to push the new tag:"
 	@echo "  git push origin $(NEW_TAG)"
-	@echo "And draft a new release at https://github.com/pokt-network/smt/releases/new"
+	@echo "And draft a new release at https://github.com/pokt-network/smt/releases/new"

kvstore/badger/kvstore.go

@@ -112,14 +112,12 @@ func (store *badgerKVStore) GetAll(prefix []byte, descending bool) (keys, values
 	return keys, values, nil
 }
 
-// Exists checks whether the key exists in the store
+// Exists checks whether the key exists in the store without retrieving the full value.
+// This avoids unnecessary memory allocations and copying that would occur with a full Get.
 func (store *badgerKVStore) Exists(key []byte) (bool, error) {
 	var exists bool
 	err := store.db.View(func(tx *badgerv4.Txn) error {
 		item, err := tx.Get(key)
-		if err == badgerv4.ErrKeyNotFound {
-			return ErrBadgerUnableToGetValue
-		}
 		if err != nil {
 			return err
 		}
@@ -196,8 +194,15 @@ func (store *badgerKVStore) Len() (int, error) {
 	return count, nil
 }
 
-// PrefixEndBytes returns the end byteslice for a noninclusive range
-// that would include all byte slices for which the input is the prefix
+// prefixEndBytes returns the end byteslice for a noninclusive range
+// that would include all byte slices for which the input is the prefix.
+// It's used in reverse iteration to set the upper bound of the key range.
+//
+// Example:
+// If prefix is []byte("user:1"), prefixEndBytes returns []byte("user:2").
+// This ensures that in reverse iteration:
+// - Keys like "user:1", "user:1:profile", "user:10" are included.
+// - But "user:2", "user:2:profile" are not included.
 func prefixEndBytes(prefix []byte) []byte {
 	if len(prefix) == 0 {
 		return nil

kvstore/pebble/kvstore.go

@@ -148,7 +148,19 @@ func (store *pebbleKVStore) Len() (int, error) {
 	return count, nil
 }
 
-// prefixEndBytes returns the end key for prefix scans.
+// prefixEndBytes returns the end byte slice for a noninclusive range
+// that would include all byte slices for which the input is the prefix.
+// It's used in reverse iteration to set the upper bound of the key range.
+//
+// Example:
+// If prefix is []byte("user:1"), prefixEndBytes returns []byte("user:2").
+// This ensures that in reverse iteration:
+// - Keys like "user:1", "user:1:profile", "user:10" are included.
+// - But "user:2", "user:2:profile" are not included.
+//
+// See `TestPebble_KVStore_GetAllWithPrefixEnd` for more examples.
+//
+// Note: This function assumes the prefix is composed of standard ASCII characters.
 func prefixEndBytes(prefix []byte) []byte {
 	if len(prefix) == 0 {
 		return nil

kvstore/pebble/kvstore_test.go

@@ -352,6 +352,69 @@ func TestPebble_KVStore_Len(t *testing.T) {
 	}
 }
 
+func TestPebble_KVStore_GetAllWithPrefixEnd(t *testing.T) {
+	store, err := pebble.NewKVStore("")
+	require.NoError(t, err)
+	require.NotNil(t, store)
+
+	keys := [][]byte{
+		[]byte("user:1"),
+		[]byte("user:10"),
+		[]byte("user:100"),
+		[]byte("user:2"),
+		[]byte("user:20"),
+	}
+	values := [][]byte{
+		[]byte("value1"),
+		[]byte("value10"),
+		[]byte("value100"),
+		[]byte("value2"),
+		[]byte("value20"),
+	}
+
+	for i := 0; i < len(keys); i++ {
+		err := store.Set(keys[i], values[i])
+		require.NoError(t, err)
+	}
+
+	t.Run("GetAll with prefix user:1", func(t *testing.T) {
+		expectedKeys := [][]byte{
+			[]byte("user:1"),
+			[]byte("user:10"),
+			[]byte("user:100"),
+		}
+		expectedValues := [][]byte{
+			[]byte("value1"),
+			[]byte("value10"),
+			[]byte("value100"),
+		}
+
+		allKeys, allValues, err := store.GetAll([]byte("user:1"), false)
+		require.NoError(t, err)
+		require.Equal(t, expectedKeys, allKeys)
+		require.Equal(t, expectedValues, allValues)
+	})
+
+	t.Run("GetAll with prefix user:2", func(t *testing.T) {
+		expectedKeys := [][]byte{
+			[]byte("user:2"),
+			[]byte("user:20"),
+		}
+		expectedValues := [][]byte{
+			[]byte("value2"),
+			[]byte("value20"),
+		}
+
+		allKeys, allValues, err := store.GetAll([]byte("user:2"), false)
+		require.NoError(t, err)
+		require.Equal(t, expectedKeys, allKeys)
+		require.Equal(t, expectedValues, allValues)
+	})
+
+	err = store.Stop()
+	require.NoError(t, err)
+}
+
 func setupStore(t *testing.T, store pebble.PebbleKVStore) {
 	t.Helper()
 	err := store.Set([]byte("foo"), []byte("bar"))