add the minimal test

Author: bhimrazy

tests/tests_pytorch/trainer/connectors/test_accelerator_connector.py

@@ -582,6 +582,11 @@ class AcceleratorSubclass(CPUAccelerator):
     Trainer(accelerator=AcceleratorSubclass(), strategy=FSDPStrategySubclass())
 
 
+@RunIf(min_cuda_gpus=1)
+def test_check_fsdp_strategy_and_fallback_with_cudaaccelerator():
+    Trainer(strategy="fsdp", accelerator=CUDAAccelerator(), devices=1, fast_dev_run=True)
+
+
 @mock.patch.dict(os.environ, {}, clear=True)
 def test_unsupported_tpu_choice(xla_available, tpu_available):
     # if user didn't set strategy, _Connector will choose the SingleDeviceXLAStrategy or XLAStrategy
@@ -1080,20 +1085,3 @@ def test_precision_selection_model_parallel(precision, raises, mps_count_0):
     with error_context:
         _AcceleratorConnector(precision=precision, strategy=ModelParallelStrategy())
 
-
-@RunIf(min_cuda_gpus=1)
-def test_fsdp_with_cudaaccelerator_instance(tmp_path):
-    # Minimal test to ensure FSDP works with CUDAAccelerator instance
-    from lightning.pytorch.demos.boring_classes import BoringModel
-
-    model = BoringModel()
-    trainer = Trainer(
-        default_root_dir=tmp_path,
-        max_epochs=1,
-        strategy="fsdp",
-        accelerator=CUDAAccelerator(),
-        devices=1,
-        fast_dev_run=True,
-    )
-    # Should not raise ValueError
-    trainer.fit(model)