fix(tests): set_filter must be used in with-block

This makes sure filters are properly cleared when the with-block exits

python/src/trezorlib/debuglink.py

@@ -407,6 +407,9 @@ class TrezorClientDebugLink(TrezorClient):
 
         Useful for test scenarios with an active malicious actor on the wire.
         """
+        if not self.in_with_statement:
+            raise RuntimeError("Must be called inside 'with' statement")
+
         self.filters[message_type] = callback
 
     def _filter_message(self, msg):
@@ -477,6 +480,7 @@ class TrezorClientDebugLink(TrezorClient):
 
         self.in_with_statement -= 1
         self.ui.clear()
+        self.filters.clear()
         self.watch_layout(False)
 
         if _type is not None:

tests/device_tests/test_msg_signtx.py

@@ -826,12 +826,12 @@ class TestMsgSigntx:
 
             return msg
 
-        # Set up attack processors
+        with client, pytest.raises(
-        client.set_filter(messages.TxAck, attack_processor)
-
-        with pytest.raises(
             TrezorFailure, match="Transaction has changed during signing"
         ):
+            # Set up attack processors
+            client.set_filter(messages.TxAck, attack_processor)
+
             btc.sign_tx(
                 client,
                 "Bitcoin",
@@ -879,12 +879,12 @@ class TestMsgSigntx:
 
             return msg
 
-        # Set up attack processors
+        with client, pytest.raises(
-        client.set_filter(messages.TxAck, attack_processor)
-
-        with pytest.raises(
             TrezorFailure, match="Transaction has changed during signing"
         ):
+            # Set up attack processors
+            client.set_filter(messages.TxAck, attack_processor)
+
             btc.sign_tx(
                 client, "Testnet", [inp1], [out1, out2], prev_txes=TX_CACHE_TESTNET
             )
@@ -933,9 +933,9 @@ class TestMsgSigntx:
 
             return msg
 
-        client.set_filter(messages.TxAck, attack_processor)
         # Now run the attack, must trigger the exception
         with client:
+            client.set_filter(messages.TxAck, attack_processor)
             client.set_expected_responses(
                 [
                     request_input(0),

tests/device_tests/test_msg_signtx_bcash.py

@@ -230,9 +230,8 @@ class TestMsgSigntxBch:
 
             return msg
 
-        client.set_filter(proto.TxAck, attack_processor)
-
         with client:
+            client.set_filter(proto.TxAck, attack_processor)
             client.set_expected_responses(
                 [
                     request_input(0),

tests/device_tests/test_msg_signtx_bgold.py

@@ -172,8 +172,8 @@ class TestMsgSigntxBitcoinGold:
 
             return msg
 
-        client.set_filter(proto.TxAck, attack_processor)
         with client:
+            client.set_filter(proto.TxAck, attack_processor)
             client.set_expected_responses(
                 [
                     request_input(0),

tests/device_tests/test_msg_signtx_segwit.py

@@ -319,8 +319,8 @@ class TestMsgSigntxSegwit:
             return msg
 
         # Now run the attack, must trigger the exception
-        client.set_filter(proto.TxAck, attack_processor)
         with client:
+            client.set_filter(proto.TxAck, attack_processor)
             client.set_expected_responses(
                 [
                     request_input(0),

tests/device_tests/test_multisig.py

@@ -294,8 +294,8 @@ class TestMultisig:
                 attack_count -= 1
             return msg
 
-        client.set_filter(proto.TxAck, attack_processor)
         with client:
+            client.set_filter(proto.TxAck, attack_processor)
             client.set_expected_responses(
                 [
                     request_input(0),