[FBcode->GH] Better logic for ignoring CPU tests on GPU CI machines (#4025) (#4062)

Author: NicolasHug

test/conftest.py

@@ -8,6 +8,9 @@ def pytest_configure(config):
     config.addinivalue_line(
         "markers", "needs_cuda: mark for tests that rely on a CUDA device"
     )
+    config.addinivalue_line(
+        "markers", "dont_collect: mark for tests that should not be collected"
+    )
 
 
 def pytest_collection_modifyitems(items):
@@ -47,6 +50,10 @@ def pytest_collection_modifyitems(items):
                 # to run the CPU-only tests.
                 item.add_marker(pytest.mark.skip(reason=CIRCLECI_GPU_NO_CUDA_MSG))
 
+        if item.get_closest_marker('dont_collect') is not None:
+            # currently, this is only used for some tests we're sure we dont want to run on fbcode
+            continue
+
         out_items.append(item)
 
     items[:] = out_items

test/test_image.py

@@ -358,6 +358,18 @@ def test_encode_jpeg_errors():
         encode_jpeg(torch.empty((100, 100), dtype=torch.uint8))
 
 
+def _collect_if(cond):
+    # TODO: remove this once test_encode_jpeg_reference and test_write_jpeg_reference
+    # are removed
+    def _inner(test_func):
+        if cond:
+            return test_func
+        else:
+            return pytest.mark.dont_collect(test_func)
+    return _inner
+
+
+@_collect_if(cond=IS_WINDOWS)
 @pytest.mark.parametrize('img_path', [
     pytest.param(jpeg_path, id=_get_safe_image_name(jpeg_path))
     for jpeg_path in get_images(ENCODE_JPEG, ".jpg")
@@ -389,6 +401,7 @@ def test_encode_jpeg_reference(img_path):
         assert_equal(jpeg_bytes, pil_bytes)
 
 
+@_collect_if(cond=IS_WINDOWS)
 @pytest.mark.parametrize('img_path', [
     pytest.param(jpeg_path, id=_get_safe_image_name(jpeg_path))
     for jpeg_path in get_images(ENCODE_JPEG, ".jpg")