feat: Adjust SignatureError with helpful tip on including sender=…

… tx kwarg (#1826)

Co-authored-by: Juliya Smith <jules@apeworx.io>

src/ape_ethereum/transactions.py

@@ -57,7 +57,14 @@ class AccessList(BaseModel):
 class BaseTransaction(TransactionAPI):
     def serialize_transaction(self) -> bytes:
         if not self.signature:
-            raise SignatureError("The transaction is not signed.")
+            message = "The transaction is not signed."
+            if not self.sender:
+                message = (
+                    f"{message} "
+                    "Did you forget to add the `sender=` kwarg to the transaction function call?"
+                )
+
+            raise SignatureError(message)
 
         txn_data = self.model_dump(by_alias=True, exclude={"sender", "type"})
 

tests/functional/test_transaction.py

@@ -1,6 +1,7 @@
 import pytest
 from eth_pydantic_types import HexBytes
 
+from ape.exceptions import SignatureError
 from ape_ethereum.transactions import DynamicFeeTransaction, StaticFeeTransaction, TransactionType
 
 
@@ -91,3 +92,31 @@ def test_txn_str_when_data_is_bytes(ethereum):
 def test_transaction_with_none_receipt(ethereum):
     txn = ethereum.create_transaction(data=HexBytes("0x123"))
     assert txn.receipt is None
+
+
+def test_serialize_transaction(owner, ethereum):
+    txn = ethereum.create_transaction(
+        data=HexBytes("0x123"), max_fee=0, max_priority_fee=0, nonce=0
+    )
+    txn = owner.sign_transaction(txn)
+    assert txn is not None
+
+    actual = txn.serialize_transaction()
+    assert isinstance(actual, bytes)
+
+
+def test_serialize_transaction_missing_signature(ethereum, owner):
+    expected = r"The transaction is not signed."
+    txn = ethereum.create_transaction(data=HexBytes("0x123"), sender=owner.address)
+    with pytest.raises(SignatureError, match=expected):
+        txn.serialize_transaction()
+
+
+def test_serialize_transaction_missing_signature_and_sender(ethereum):
+    expected = (
+        r"The transaction is not signed. "
+        r"Did you forget to add the `sender=` kwarg to the transaction function call?"
+    )
+    txn = ethereum.create_transaction(data=HexBytes("0x123"))
+    with pytest.raises(SignatureError, match=expected):
+        txn.serialize_transaction()