supports overwriting pending txns that use the same nonce

Author: YanhuiJessica

cheb3/account.py

@@ -106,7 +106,7 @@ def send_transaction(
             "from": self.address,
             "to": to,
             "chainId": self.w3.eth.chain_id,
-            "nonce": self.w3.eth.get_transaction_count(self.address),
+            "nonce": kwargs.get("nonce", self.w3.eth.get_transaction_count(self.address)),
             "value": value,
             "gasPrice": kwargs.get("gas_price", self.w3.eth.gas_price),
             "data": data,

cheb3/contract.py

@@ -229,7 +229,7 @@ def send_transaction(self, **kwargs) -> TxReceipt:
             estimate_gas = 3000000
         tx = {
             "chainId": self.w3.eth.chain_id,
-            "nonce": self.w3.eth.get_transaction_count(self.signer.address),
+            "nonce": kwargs.get("nonce", self.w3.eth.get_transaction_count(self.signer.address)),
             "gasPrice": kwargs.get("gas_price", self.w3.eth.gas_price),
             "value": kwargs.get("value", 0),
             "gas": kwargs.get("gas_limit", estimate_gas),