fix: duplicate set_default_max_transaction_fee in e2e test and improve test surface area to check default is applied if not set

Signed-off-by: exploreriii <133720349+exploreriii@users.noreply.github.com>

Author: exploreriii

src/hiero_sdk_python/transaction/transaction.py

@@ -9,17 +9,9 @@
 from hiero_sdk_python.crypto.key import Key
 from hiero_sdk_python.exceptions import PrecheckError
 from hiero_sdk_python.executable import _Executable, _ExecutionState
-from hiero_sdk_python.hapi.services import (
-    basic_types_pb2,
-    transaction_contents_pb2,
-    transaction_pb2,
-)
-from hiero_sdk_python.hapi.services.schedulable_transaction_body_pb2 import (
-    SchedulableTransactionBody,
-)
-from hiero_sdk_python.hapi.services.transaction_response_pb2 import (
-    TransactionResponse as TransactionResponseProto,
-)
+from hiero_sdk_python.hapi.services import basic_types_pb2, transaction_contents_pb2, transaction_pb2
+from hiero_sdk_python.hapi.services.schedulable_transaction_body_pb2 import SchedulableTransactionBody
+from hiero_sdk_python.hapi.services.transaction_response_pb2 import TransactionResponse as TransactionResponseProto
 from hiero_sdk_python.hbar import Hbar
 from hiero_sdk_python.query.fee_estimate_query import FeeEstimateQuery
 from hiero_sdk_python.response_code import ResponseCode
@@ -322,10 +314,6 @@ def freeze_with(self, client: Client):
         # We iterate through every node in the node_account_id list and
         # For each node_account_id build the transaction body
         # This allows the transaction to be submitted to the given node in the network
-        #
-        # Batch inner transactions (node 0.0.0), explicitly-set nodes, and the
-        # fall-back to all client network nodes are all resolved by
-        # _resolve_node_ids(client) above, so this single loop covers every case.
 
         # TODO: Should lock the node_account_ids once freeze
         # self._node_account_ids.set_lock(True)

tests/integration/account_update_transaction_e2e_test.py

@@ -248,7 +248,6 @@ def _apply_tiny_max_fee_if_supported(tx, client) -> bool:
             return True
     # Try client-level default
     for attr in (
-        "set_default_max_transaction_fee",
         "set_default_max_transaction_fee",
         "set_default_max_fee",
         "setMaxTransactionFee",
@@ -295,6 +294,29 @@ def test_account_update_insufficient_fee_with_valid_expiration_bump(env):
     assert int(info_after.expiration_time.seconds) == base_expiry_secs
 
 
+@pytest.mark.integration
+def test_account_update_insufficient_fee_via_client_default(env):
+    """A client-level default max fee must apply to transactions that set no explicit fee."""
+    receipt = (
+        AccountCreateTransaction()
+        .set_key(env.operator_key.public_key())
+        .set_initial_balance(Hbar(1))
+        .execute(env.client)
+    )
+    assert receipt.status == ResponseCode.SUCCESS
+    account_id = receipt.account_id
+
+    env.client.set_default_max_transaction_fee(Hbar.from_tinybars(1))
+
+    # No tx-level fee: the 1-tinybar client default must be resolved at freeze and rejected at precheck.
+    tx = AccountUpdateTransaction().set_account_id(account_id).set_account_memo("client default fee test")
+
+    with pytest.raises(PrecheckError) as exc_info:
+        tx.execute(env.client)
+
+    assert exc_info.value.status == ResponseCode.INSUFFICIENT_TX_FEE
+
+
 @pytest.mark.integration
 def test_integration_account_update_transaction_with_only_account_id(env):
     """Test that AccountUpdateTransaction can execute with only account ID set."""