Fix review issues, add UTs

proxy/plugin/solana_rest_api.py

@@ -200,11 +200,14 @@ def eth_getStorageAt(self, account, position, block_identifier):
         Currently supports only 'latest' block
         '''
         if block_identifier != "latest":
-            print(f"Block type '{block_identifier}' is not supported yet")
-            raise RuntimeError("Not supported block")
-        value = neon_cli().call('get-ether-storage-at', account, position)
-        print(f"eth_getStorageAt >> '{value}'")
-        return value
+            logger.debug(f"Block type '{block_identifier}' is not supported yet")
+            raise RuntimeError(f"Not supported block identifier: {block_identifier}")
+
+        try:
+            value = neon_cli().call('get-storage-at', account, position)
+            return value
+        except:
+            return '0x0'
 
     def eth_getBlockByHash(self, trx_hash, full):
         """Returns information about a block by hash.

proxy/test_eth_sendRawTransaction.py

@@ -440,10 +440,21 @@ def test_get_storage_at(self):
         print('trx_store_hash:', trx_store_hash.hex())
         trx_store_receipt = proxy.eth.wait_for_transaction_receipt(trx_store_hash)
         print('trx_store_receipt:', trx_store_receipt)
-        value_received = proxy.eth.get_storage_at(self.storage_contract.address, 0, "latest")
-        print('eth_getStorageAt return:', value_received.hex())
+
+        number_pos = 0
+        value_received = proxy.eth.get_storage_at(self.storage_contract.address, number_pos, "latest")
+        print('eth_getStorageAt existing address and index => ', value_received.hex())
         self.assertEqual(int.from_bytes(value_received, byteorder='big'), value_to_store)
 
+        non_existing_pos = 12
+        value_received = proxy.eth.get_storage_at(self.storage_contract.address, non_existing_pos, "latest")
+        print('eth_getStorageAt existing address and non-existing index => ', value_received.hex())
+        self.assertEqual(int.from_bytes(value_received, byteorder='big'), 0)
+
+        non_exising_address = b'\xe1\xda\xb7\xa6\x17\x6f\x87\x68\xF5\x3a\x42\x5f\x29\x61\x73\x60\x5e\xd5\x08\x32'
+        value_received = proxy.eth.get_storage_at(non_exising_address, non_existing_pos, "latest")
+        print('eth_getStorageAt non-existing address => ', value_received.hex())
+        self.assertEqual(int.from_bytes(value_received, byteorder='big'), 0)
 
 if __name__ == '__main__':
     unittest.main()