Fixes getStorageAt undeployed contract response

fix

Revert "Fixes getStorageAt undeployed contract response"

This reverts commit bd44ef2d79ace6abe9358c053ea3b640dc389bb0.

fix

fix test

fix

fix

rpc/contract.go

@@ -39,6 +39,13 @@ func (h *Handler) StorageAt(address, key felt.Felt, id BlockID) (*felt.Felt, *js
 	}
 	defer h.callAndLogErr(stateCloser, "Error closing state reader in getStorageAt")
 
+	// This checks if the contract exists because if a key doesn't exist in contract storage,
+	// the returned value is always zero and error is nil.
+	_, err := stateReader.ContractNonce(&address)
+	if err != nil {
+		return nil, ErrContractNotFound
+	}
+
 	value, err := stateReader.ContractStorage(&address, &key)
 	if err != nil {
 		return nil, ErrContractNotFound

rpc/contract_test.go

@@ -123,7 +123,8 @@ func TestStorageAt(t *testing.T) {
 
 	t.Run("non-existent contract", func(t *testing.T) {
 		mockReader.EXPECT().HeadState().Return(mockState, nopCloser, nil)
-		mockState.EXPECT().ContractStorage(gomock.Any(), gomock.Any()).Return(nil, errors.New("non-existent contract"))
+		// we check if the contract exists by getting its nonce
+		mockState.EXPECT().ContractNonce(gomock.Any()).Return(nil, errors.New("non-existent contract"))
 
 		storage, rpcErr := handler.StorageAt(felt.Zero, felt.Zero, rpc.BlockID{Latest: true})
 		require.Nil(t, storage)
@@ -132,7 +133,8 @@ func TestStorageAt(t *testing.T) {
 
 	t.Run("non-existent key", func(t *testing.T) {
 		mockReader.EXPECT().HeadState().Return(mockState, nopCloser, nil)
-		mockState.EXPECT().ContractStorage(gomock.Any(), gomock.Any()).Return(&felt.Zero, errors.New("non-existent key"))
+		// we check if the contract exists by getting its nonce
+		mockState.EXPECT().ContractNonce(gomock.Any()).Return(nil, errors.New("non-existent contract"))
 
 		storage, rpcErr := handler.StorageAt(felt.Zero, felt.Zero, rpc.BlockID{Latest: true})
 		require.Nil(t, storage)
@@ -143,6 +145,7 @@ func TestStorageAt(t *testing.T) {
 
 	t.Run("blockID - latest", func(t *testing.T) {
 		mockReader.EXPECT().HeadState().Return(mockState, nopCloser, nil)
+		mockState.EXPECT().ContractNonce(&felt.Zero).Return(nil, nil)
 		mockState.EXPECT().ContractStorage(gomock.Any(), gomock.Any()).Return(expectedStorage, nil)
 
 		storage, rpcErr := handler.StorageAt(felt.Zero, felt.Zero, rpc.BlockID{Latest: true})
@@ -152,6 +155,7 @@ func TestStorageAt(t *testing.T) {
 
 	t.Run("blockID - hash", func(t *testing.T) {
 		mockReader.EXPECT().StateAtBlockHash(&felt.Zero).Return(mockState, nopCloser, nil)
+		mockState.EXPECT().ContractNonce(&felt.Zero).Return(nil, nil)
 		mockState.EXPECT().ContractStorage(gomock.Any(), gomock.Any()).Return(expectedStorage, nil)
 
 		storage, rpcErr := handler.StorageAt(felt.Zero, felt.Zero, rpc.BlockID{Hash: &felt.Zero})
@@ -161,6 +165,7 @@ func TestStorageAt(t *testing.T) {
 
 	t.Run("blockID - number", func(t *testing.T) {
 		mockReader.EXPECT().StateAtBlockNumber(uint64(0)).Return(mockState, nopCloser, nil)
+		mockState.EXPECT().ContractNonce(&felt.Zero).Return(nil, nil)
 		mockState.EXPECT().ContractStorage(gomock.Any(), gomock.Any()).Return(expectedStorage, nil)
 
 		storage, rpcErr := handler.StorageAt(felt.Zero, felt.Zero, rpc.BlockID{Number: 0})