Method load

test/builtin_dataset_mocks.py:64–108

(self, config)

        return mock_info

    def load(self, config):
        # `datasets.home()` is patched to a temporary directory through the autouse fixture `test_home` in
        # test/test_prototype_builtin_datasets.py
        root = pathlib.Path(datasets.home()) / self.name
        # We cannot place the mock data upfront in `root`. Loading a dataset calls `OnlineResource.load`. In turn,
        # this will only download **and** preprocess if the file is not present. In other words, if we already place
        # the file in `root` before the resource is loaded, we are effectively skipping the preprocessing.
        # To avoid that we first place the mock data in a temporary directory and patch the download logic to move it to
        # `root` only when it is requested.
        tmp_mock_data_folder = root / "__mock__"
        tmp_mock_data_folder.mkdir(parents=True)

        mock_info = self._parse_mock_info(self.mock_data_fn(tmp_mock_data_folder, config))

        def patched_download(resource, root, **kwargs):
            src = tmp_mock_data_folder / resource.file_name
            if not src.exists():
                raise pytest.UsageError(
                    f"Dataset '{self.name}' requires the file {resource.file_name} for {config}"
                    f"but it was not created by the mock data function."
                )

            dst = root / resource.file_name
            shutil.move(str(src), str(root))

            return dst

        with unittest.mock.patch(
            "torchvision.prototype.datasets.utils._resource.OnlineResource.download", new=patched_download
        ):
            dataset = datasets.load(self.name, **config)

        extra_files = list(tmp_mock_data_folder.glob("**/*"))
        if extra_files:
            raise pytest.UsageError(
                (
                    f"Dataset '{self.name}' created the following files for {config} in the mock data function, "
                    f"but they were not loaded:\n\n"
                )
                + "\n".join(str(file.relative_to(tmp_mock_data_folder)) for file in extra_files)
            )

        tmp_mock_data_folder.rmdir()

        return dataset, mock_info


def config_id(name, config):