diff --git a/src/ophyd_async/testing/_assert.py b/src/ophyd_async/testing/_assert.py
index 48d8a35538..7b1623127b 100644
--- a/src/ophyd_async/testing/_assert.py
+++ b/src/ophyd_async/testing/_assert.py
@@ -79,12 +79,12 @@ async def assert_reading(
 
     """
     actual_reading = await readable.read()
-    assert (
-        _approx_readable_value(expected_reading) == actual_reading
-    ), _generate_assert_error_msg(
-        name=readable.name,
-        expected_result=expected_reading,
-        actual_result=actual_reading,
+    assert _approx_readable_value(expected_reading) == actual_reading, (
+        _generate_assert_error_msg(
+            name=readable.name,
+            expected_result=expected_reading,
+            actual_result=actual_reading,
+        )
     )
 
 
@@ -109,12 +109,12 @@ async def assert_configuration(
 
     """
     actual_configurable = await configurable.read_configuration()
-    assert (
-        _approx_readable_value(configuration) == actual_configurable
-    ), _generate_assert_error_msg(
-        name=configurable.name,
-        expected_result=configuration,
-        actual_result=actual_configurable,
+    assert _approx_readable_value(configuration) == actual_configurable, (
+        _generate_assert_error_msg(
+            name=configurable.name,
+            expected_result=configuration,
+            actual_result=actual_configurable,
+        )
     )
 
 
diff --git a/src/ophyd_async/testing/_mock_signal_utils.py b/src/ophyd_async/testing/_mock_signal_utils.py
index 683666e6b4..b5077b637c 100644
--- a/src/ophyd_async/testing/_mock_signal_utils.py
+++ b/src/ophyd_async/testing/_mock_signal_utils.py
@@ -22,9 +22,9 @@ def get_mock(device: Device | Signal) -> Mock:
 def _get_mock_signal_backend(signal: Signal) -> MockSignalBackend:
     connector = signal._connector  # noqa: SLF001
     assert isinstance(connector, SignalConnector), f"Expected Signal, got {signal}"
-    assert isinstance(
-        connector.backend, MockSignalBackend
-    ), f"Signal {signal} not connected in mock mode"
+    assert isinstance(connector.backend, MockSignalBackend), (
+        f"Signal {signal} not connected in mock mode"
+    )
     return connector.backend
 
 
diff --git a/tests/fastcs/panda/test_seq_table.py b/tests/fastcs/panda/test_seq_table.py
index 69a2b5f7a7..d42567e5a1 100644
--- a/tests/fastcs/panda/test_seq_table.py
+++ b/tests/fastcs/panda/test_seq_table.py
@@ -62,8 +62,7 @@ def test_seq_table_validation_errors():
     with pytest.raises(
         ValidationError,
         match=(
-            "1 validation error for SeqTable\n  "
-            "Value error, Length 4097 is too long."
+            "1 validation error for SeqTable\n  Value error, Length 4097 is too long."
         ),
     ):
         large_seq_table + SeqTable.row()
diff --git a/tests/sim/test_sim_detector.py b/tests/sim/test_sim_detector.py
index 6e6c94c8bc..b35ff72d65 100644
--- a/tests/sim/test_sim_detector.py
+++ b/tests/sim/test_sim_detector.py
@@ -15,9 +15,9 @@
 async def test_sim_pattern_detector_initialization(
     sim_pattern_detector: PatternDetector,
 ):
-    assert (
-        sim_pattern_detector.pattern_generator
-    ), "PatternGenerator was not initialized correctly."
+    assert sim_pattern_detector.pattern_generator, (
+        "PatternGenerator was not initialized correctly."
+    )
 
 
 async def test_detector_creates_controller_and_writer(