tests/single_file/test_model_sd_cascade_unet_single_file.py

# coding=utf-8
# Copyright 2025 HuggingFace Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import gc

import torch

from diffusers import StableCascadeUNet
from diffusers.utils import logging

from ..testing_utils import (
    backend_empty_cache,
    enable_full_determinism,
    require_torch_accelerator,
    slow,
    torch_device,
)


logger = logging.get_logger(__name__)

enable_full_determinism()


@slow
@require_torch_accelerator
class StableCascadeUNetSingleFileTest:
    def setup_method(self):
        gc.collect()
        backend_empty_cache(torch_device)

    def teardown_method(self):
        gc.collect()
        backend_empty_cache(torch_device)

    def test_single_file_components_stage_b(self):
        model_single_file = StableCascadeUNet.from_single_file(
            "https://huggingface.co/stabilityai/stable-cascade/blob/main/stage_b_bf16.safetensors",
            torch_dtype=torch.bfloat16,
        )
        model = StableCascadeUNet.from_pretrained(
            "stabilityai/stable-cascade", variant="bf16", subfolder="decoder", use_safetensors=True
        )

        PARAMS_TO_IGNORE = ["torch_dtype", "_name_or_path", "_use_default_values", "_diffusers_version"]
        for param_name, param_value in model_single_file.config.items():
            if param_name in PARAMS_TO_IGNORE:
                continue
            assert model.config[param_name] == param_value, (
                f"{param_name} differs between single file loading and pretrained loading"
            )

    def test_single_file_components_stage_b_lite(self):
        model_single_file = StableCascadeUNet.from_single_file(
            "https://huggingface.co/stabilityai/stable-cascade/blob/main/stage_b_lite_bf16.safetensors",
            torch_dtype=torch.bfloat16,
        )
        model = StableCascadeUNet.from_pretrained(
            "stabilityai/stable-cascade", variant="bf16", subfolder="decoder_lite"
        )

        PARAMS_TO_IGNORE = ["torch_dtype", "_name_or_path", "_use_default_values", "_diffusers_version"]
        for param_name, param_value in model_single_file.config.items():
            if param_name in PARAMS_TO_IGNORE:
                continue
            assert model.config[param_name] == param_value, (
                f"{param_name} differs between single file loading and pretrained loading"
            )

    def test_single_file_components_stage_c(self):
        model_single_file = StableCascadeUNet.from_single_file(
            "https://huggingface.co/stabilityai/stable-cascade/blob/main/stage_c_bf16.safetensors",
            torch_dtype=torch.bfloat16,
        )
        model = StableCascadeUNet.from_pretrained(
            "stabilityai/stable-cascade-prior", variant="bf16", subfolder="prior"
        )

        PARAMS_TO_IGNORE = ["torch_dtype", "_name_or_path", "_use_default_values", "_diffusers_version"]
        for param_name, param_value in model_single_file.config.items():
            if param_name in PARAMS_TO_IGNORE:
                continue
            assert model.config[param_name] == param_value, (
                f"{param_name} differs between single file loading and pretrained loading"
            )

    def test_single_file_components_stage_c_lite(self):
        model_single_file = StableCascadeUNet.from_single_file(
            "https://huggingface.co/stabilityai/stable-cascade/blob/main/stage_c_lite_bf16.safetensors",
            torch_dtype=torch.bfloat16,
        )
        model = StableCascadeUNet.from_pretrained(
            "stabilityai/stable-cascade-prior", variant="bf16", subfolder="prior_lite"
        )

        PARAMS_TO_IGNORE = ["torch_dtype", "_name_or_path", "_use_default_values", "_diffusers_version"]
        for param_name, param_value in model_single_file.config.items():
            if param_name in PARAMS_TO_IGNORE:
                continue
            assert model.config[param_name] == param_value, (
                f"{param_name} differs between single file loading and pretrained loading"
            )