[Tests] restrict memory tests for quanto for certain schemes. (#11052)

* restrict memory tests for quanto for certain schemes.

* Apply suggestions from code review
Co-authored-by: Dhruv Nair <dhruv.nair@gmail.com>

* fixes

* style

---------
Co-authored-by: Dhruv Nair <dhruv.nair@gmail.com>

src/diffusers/utils/testing_utils.py

@@ -101,6 +101,8 @@ if is_torch_available():
             mps_backend_registered = hasattr(torch.backends, "mps")
             torch_device = "mps" if (mps_backend_registered and torch.backends.mps.is_available()) else torch_device
 
+    from .torch_utils import get_torch_cuda_device_capability
+
 
 def torch_all_close(a, b, *args, **kwargs):
     if not is_torch_available():
@@ -282,6 +284,20 @@ def require_torch_gpu(test_case):
     )
 
 
+def require_torch_cuda_compatibility(expected_compute_capability):
+    def decorator(test_case):
+        if not torch.cuda.is_available():
+            return unittest.skip(test_case)
+        else:
+            current_compute_capability = get_torch_cuda_device_capability()
+            return unittest.skipUnless(
+                float(current_compute_capability) == float(expected_compute_capability),
+                "Test not supported for this compute capability.",
+            )
+
+    return decorator
+
+
 # These decorators are for accelerator-specific behaviours that are not GPU-specific
 def require_torch_accelerator(test_case):
     """Decorator marking a test that requires an accelerator backend and PyTorch."""

tests/quantization/quanto/test_quanto.py

@@ -10,6 +10,7 @@ from diffusers.utils.testing_utils import (
     numpy_cosine_similarity_distance,
     require_accelerate,
     require_big_gpu_with_torch_cuda,
+    require_torch_cuda_compatibility,
     torch_device,
 )
 
@@ -311,6 +312,7 @@ class FluxTransformerInt8WeightsTest(FluxTransformerQuantoMixin, unittest.TestCa
         return {"weights_dtype": "int8"}
 
 
+@require_torch_cuda_compatibility(8.0)
 class FluxTransformerInt4WeightsTest(FluxTransformerQuantoMixin, unittest.TestCase):
     expected_memory_reduction = 0.55
 
@@ -318,6 +320,7 @@ class FluxTransformerInt4WeightsTest(FluxTransformerQuantoMixin, unittest.TestCa
         return {"weights_dtype": "int4"}
 
 
+@require_torch_cuda_compatibility(8.0)
 class FluxTransformerInt2WeightsTest(FluxTransformerQuantoMixin, unittest.TestCase):
     expected_memory_reduction = 0.65