*: return errors.ErrUnsupported where appropriate

Signed-off-by: Roman Khimov <roman@nspcc.ru>

pkg/core/mpt/trie_store.go

@@ -21,10 +21,6 @@ type TrieStore struct {
 	trie *Trie
 }
 
-// ErrForbiddenTrieStoreOperation is returned when operation is not supposed to
-// be performed over MPT-based Store.
-var ErrForbiddenTrieStoreOperation = errors.New("operation is not allowed to be performed over TrieStore")
-
 // NewTrieStore returns a new ready to use MPT-backed storage.
 func NewTrieStore(root util.Uint256, mode TrieMode, backed storage.Store) *TrieStore {
 	cache, ok := backed.(*storage.MemCachedStore)
@@ -37,10 +33,11 @@ func NewTrieStore(root util.Uint256, mode TrieMode, backed storage.Store) *TrieS
 	}
 }
 
-// Get implements the Store interface.
+// Get implements the Store interface. It can return [errors.ErrUnsupported]
+// for unsupported operations.
 func (m *TrieStore) Get(key []byte) ([]byte, error) {
 	if len(key) == 0 {
-		return nil, fmt.Errorf("%w: Get is supported only for contract storage items", ErrForbiddenTrieStoreOperation)
+		return nil, fmt.Errorf("%w: Get is supported only for contract storage items", errors.ErrUnsupported)
 	}
 	switch storage.KeyPrefix(key[0]) {
 	case storage.STStorage, storage.STTempStorage:
@@ -51,22 +48,23 @@ func (m *TrieStore) Get(key []byte) ([]byte, error) {
 		}
 		return res, err
 	default:
-		return nil, fmt.Errorf("%w: Get is supported only for contract storage items", ErrForbiddenTrieStoreOperation)
+		return nil, fmt.Errorf("%w: Get is supported only for contract storage items", errors.ErrUnsupported)
 	}
 }
 
-// PutChangeSet implements the Store interface.
+// PutChangeSet implements the Store interface. It's not supported, so it
+// always returns [errors.ErrUnsupported].
 func (m *TrieStore) PutChangeSet(puts map[string][]byte, stor map[string][]byte) error {
 	// Only Get and Seek should be supported, as TrieStore is read-only and is always
 	// should be wrapped by MemCachedStore to properly support put operations (if any).
-	return fmt.Errorf("%w: PutChangeSet is not supported", ErrForbiddenTrieStoreOperation)
+	return fmt.Errorf("%w: PutChangeSet is not supported", errors.ErrUnsupported)
 }
 
 // Seek implements the Store interface.
 func (m *TrieStore) Seek(rng storage.SeekRange, f func(k, v []byte) bool) {
 	prefix := storage.KeyPrefix(rng.Prefix[0])
 	if prefix != storage.STStorage && prefix != storage.STTempStorage { // Prefix is always non-empty.
-		panic(fmt.Errorf("%w: Seek is supported only for contract storage items", ErrForbiddenTrieStoreOperation))
+		panic(fmt.Errorf("%w: Seek is supported only for contract storage items", errors.ErrUnsupported))
 	}
 	prefixP := toNibbles(rng.Prefix[1:])
 	fromP := []byte{}
@@ -113,9 +111,10 @@ func (m *TrieStore) Seek(rng storage.SeekRange, f func(k, v []byte) bool) {
 	}
 }
 
-// SeekGC implements the Store interface.
+// SeekGC implements the Store interface. It's not supported, so it always
+// returns [errors.ErrUnsupported].
 func (m *TrieStore) SeekGC(rng storage.SeekRange, keep func(k, v []byte) bool) error {
-	return fmt.Errorf("%w: SeekGC is not supported", ErrForbiddenTrieStoreOperation)
+	return fmt.Errorf("%w: SeekGC is not supported", errors.ErrUnsupported)
 }
 
 // Close implements the Store interface.

pkg/core/mpt/trie_store_test.go

@@ -2,6 +2,7 @@ package mpt
 
 import (
 	"bytes"
+	"errors"
 	"testing"
 
 	"github.com/nspcc-dev/neo-go/pkg/core/storage"
@@ -15,10 +16,10 @@ func TestTrieStore_TestTrieOperations(t *testing.T) {
 	st := NewTrieStore(source.root.Hash(), ModeAll, backed)
 
 	t.Run("forbidden operations", func(t *testing.T) {
-		require.ErrorIs(t, st.SeekGC(storage.SeekRange{}, nil), ErrForbiddenTrieStoreOperation)
+		require.ErrorIs(t, st.SeekGC(storage.SeekRange{}, nil), errors.ErrUnsupported)
 		_, err := st.Get([]byte{byte(storage.STTokenTransferInfo)})
-		require.ErrorIs(t, err, ErrForbiddenTrieStoreOperation)
-		require.ErrorIs(t, st.PutChangeSet(nil, nil), ErrForbiddenTrieStoreOperation)
+		require.ErrorIs(t, err, errors.ErrUnsupported)
+		require.ErrorIs(t, st.PutChangeSet(nil, nil), errors.ErrUnsupported)
 	})
 
 	t.Run("Get", func(t *testing.T) {

pkg/core/native/crypto.go

@@ -201,16 +201,16 @@ func curveHasherFromStackitem(si stackitem.Item, allowKeccak bool) (elliptic.Cur
 		return elliptic.P256(), hash.Sha256, nil
 	case int64(Secp256k1Keccak256):
 		if !allowKeccak {
-			return nil, nil, errors.New("unsupported hash type")
+			return nil, nil, fmt.Errorf("%w: keccak hash", errors.ErrUnsupported)
 		}
 		return secp256k1.S256(), Keccak256, nil
 	case int64(Secp256r1Keccak256):
 		if !allowKeccak {
-			return nil, nil, errors.New("unsupported hash type")
+			return nil, nil, fmt.Errorf("%w: keccak hash", errors.ErrUnsupported)
 		}
 		return elliptic.P256(), Keccak256, nil
 	default:
-		return nil, nil, errors.New("unsupported curve/hash type")
+		return nil, nil, fmt.Errorf("%w: unknown curve/hash", errors.ErrUnsupported)
 	}
 }
 

pkg/rpcclient/waiter/waiter.go

@@ -29,8 +29,8 @@ var (
 	// of transaction awaiting process and no result was received yet.
 	ErrContextDone = errors.New("waiter context done")
 	// ErrAwaitingNotSupported is returned from Wait method if Waiter instance
-	// doesn't support transaction awaiting.
-	ErrAwaitingNotSupported = errors.New("awaiting not supported")
+	// doesn't support transaction awaiting. It's compatible with [errors.ErrUnsupported].
+	ErrAwaitingNotSupported = fmt.Errorf("%w: awaiting", errors.ErrUnsupported)
 	// ErrMissedEvent is returned when RPCEventBased closes receiver channel
 	// which happens if missed event was received from the RPC server.
 	ErrMissedEvent = errors.New("some event was missed")

pkg/services/rpcsrv/params/txBuilder.go

@@ -14,7 +14,8 @@ import (
 )
 
 // ExpandFuncParameterIntoScript pushes provided FuncParam parameter
-// into the given buffer.
+// into the given buffer. Returns [errors.ErrUnsupported] for types it can't
+// process.
 func ExpandFuncParameterIntoScript(script *io.BinWriter, fp FuncParam) error {
 	switch fp.Type {
 	case smartcontract.ByteArrayType:
@@ -92,7 +93,7 @@ func ExpandFuncParameterIntoScript(script *io.BinWriter, fp FuncParam) error {
 			emit.Opcodes(script, opcode.PUSHNULL)
 		}
 	default:
-		return fmt.Errorf("parameter type %v is not supported", fp.Type)
+		return fmt.Errorf("%w: parameter type %v", errors.ErrUnsupported, fp.Type)
 	}
 	return script.Err
 }

pkg/smartcontract/parameter.go

@@ -200,7 +200,8 @@ func (p *Parameter) UnmarshalJSON(data []byte) (err error) {
 // NewParameterFromString returns a new Parameter initialized from the given
 // string in neo-go-specific format. It is intended to be used in user-facing
 // interfaces and has some heuristics in it to simplify parameter passing. The exact
-// syntax is documented in the cli documentation.
+// syntax is documented in the cli documentation. [errors.ErrUnsupported] will be
+// returned in case of unsupported parameter types.
 func NewParameterFromString(in string) (*Parameter, error) {
 	var (
 		char    rune
@@ -227,7 +228,7 @@ func NewParameterFromString(in string) (*Parameter, error) {
 			}
 			// We currently do not support following types:
 			if res.Type == ArrayType || res.Type == MapType || res.Type == InteropInterfaceType || res.Type == VoidType {
-				return nil, fmt.Errorf("unsupported parameter type %s", res.Type)
+				return nil, fmt.Errorf("%w: type %s", errors.ErrUnsupported, res.Type)
 			}
 			buf.Reset()
 			hadType = true
@@ -264,7 +265,8 @@ func NewParameterFromString(in string) (*Parameter, error) {
 // NewParameterFromValue infers Parameter type from the value given and adjusts
 // the value if needed. It does not copy the value if it can avoid doing so. All
 // regular integers, util.*, keys.PublicKey*, string and bool types are supported,
-// slice of byte slices is accepted and converted as well.
+// slice of byte slices is accepted and converted as well. [errors.ErrUnsupported]
+// will be returned for types that can't be used now.
 func NewParameterFromValue(value any) (Parameter, error) {
 	var result = Parameter{
 		Value: value,
@@ -373,7 +375,7 @@ func NewParameterFromValue(value any) (Parameter, error) {
 	case nil:
 		result.Type = AnyType
 	default:
-		return result, fmt.Errorf("unsupported parameter %T", value)
+		return result, fmt.Errorf("%w: %T type", errors.ErrUnsupported, value)
 	}
 
 	return result, nil
@@ -396,6 +398,7 @@ func NewParametersFromValues(values ...any) ([]Parameter, error) {
 // ExpandParameterToEmitable converts a parameter to a type which can be handled as
 // an array item by emit.Array. It correlates with the way an RPC server handles
 // FuncParams for invoke* calls inside the request.ExpandArrayIntoScript function.
+// [errors.ErrUnsupported] is returned for unsupported types.
 func ExpandParameterToEmitable(param Parameter) (any, error) {
 	var err error
 	switch t := param.Type; t {
@@ -410,7 +413,7 @@ func ExpandParameterToEmitable(param Parameter) (any, error) {
 		}
 		return res, nil
 	case MapType, InteropInterfaceType, UnknownType, VoidType:
-		return nil, fmt.Errorf("unsupported parameter type: %s", t.String())
+		return nil, fmt.Errorf("%w: %s type", errors.ErrUnsupported, t.String())
 	default:
 		return param.Value, nil
 	}

pkg/smartcontract/parameter_test.go

@@ -787,11 +787,11 @@ func TestParameterFromValue(t *testing.T) {
 		},
 		{
 			value: make(map[string]int),
-			err:   "unsupported parameter map[string]int",
+			err:   "unsupported operation: map[string]int type",
 		},
 		{
 			value: []any{1, 2, make(map[string]int)},
-			err:   "unsupported parameter map[string]int",
+			err:   "unsupported operation: map[string]int type",
 		},
 	}
 

pkg/vm/emit/emit.go

@@ -127,6 +127,8 @@ func Array(w *io.BinWriter, es ...any) {
 //   - stackitem.Convertible, stackitem.Item
 //   - nil
 //   - []any
+//
+// [errors.ErrUnsupported] is returned for unsupported types.
 func Any(w *io.BinWriter, something any) {
 	switch e := something.(type) {
 	case []any:
@@ -181,7 +183,7 @@ func Any(w *io.BinWriter, something any) {
 		StackItem(w, e)
 	default:
 		if something != nil {
-			w.Err = fmt.Errorf("unsupported type: %T", e)
+			w.Err = fmt.Errorf("%w: %T type", errors.ErrUnsupported, e)
 			return
 		}
 		Opcodes(w, opcode.PUSHNULL)
@@ -199,14 +201,15 @@ func Convertible(w *io.BinWriter, c stackitem.Convertible) {
 	StackItem(w, si)
 }
 
-// StackItem emits provided stackitem.Item to the given buffer.
+// StackItem emits provided stackitem.Item to the given buffer. If it can't
+// be emitted [errors.ErrUnsupported] is returned.
 func StackItem(w *io.BinWriter, si stackitem.Item) {
 	switch t := si.Type(); t {
 	case stackitem.AnyT:
 		if si.Value() == nil {
 			Opcodes(w, opcode.PUSHNULL)
 		} else {
-			w.Err = fmt.Errorf("only nil value supported for %s", t)
+			w.Err = fmt.Errorf("%w: %s can only be nil", errors.ErrUnsupported, t)
 			return
 		}
 	case stackitem.BooleanT:
@@ -240,7 +243,7 @@ func StackItem(w *io.BinWriter, si stackitem.Item) {
 		Int(w, int64(len(arr)))
 		Opcodes(w, opcode.PACKMAP)
 	default:
-		w.Err = fmt.Errorf("%s is unsuppoted", t)
+		w.Err = fmt.Errorf("%w: %s type", errors.ErrUnsupported, t)
 		return
 	}
 }

pkg/vm/emit/emit_test.go

@@ -547,7 +547,7 @@ func TestEmitStackitem(t *testing.T) {
 		for _, si := range itms {
 			buf := io.NewBufBinWriter()
 			StackItem(buf.BinWriter, si)
-			require.Error(t, buf.Err)
+			require.ErrorIs(t, buf.Err, errors.ErrUnsupported)
 		}
 	})
 
@@ -555,8 +555,8 @@ func TestEmitStackitem(t *testing.T) {
 		buf := io.NewBufBinWriter()
 		StackItem(buf.BinWriter, StrangeStackItem{})
 		actualErr := buf.Err
-		require.Error(t, actualErr)
-		require.True(t, strings.Contains(actualErr.Error(), "only nil value supported"), actualErr.Error())
+		require.ErrorIs(t, actualErr, errors.ErrUnsupported)
+		require.True(t, strings.Contains(actualErr.Error(), "Any can only be nil"), actualErr.Error())
 	})
 }