# coding=utf-8
# Copyright 2026 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 pytest
import torch

from diffusers import (
    AutoRoundConfig,
    BitsAndBytesConfig,
    GGUFQuantizationConfig,
    NunchakuLiteQuantizationConfig,
    NVIDIAModelOptConfig,
    QuantoConfig,
    SDNQConfig,
    TorchAoConfig,
)
from diffusers.utils.import_utils import (
    is_bitsandbytes_available,
    is_gguf_available,
    is_kernels_available,
    is_nvidia_modelopt_available,
    is_optimum_quanto_available,
    is_torchao_available,
)

from ...testing_utils import (
    assert_tensors_close,
    backend_empty_cache,
    backend_max_memory_allocated,
    backend_reset_peak_memory_stats,
    is_autoround,
    is_bitsandbytes,
    is_gguf,
    is_modelopt,
    is_quantization,
    is_quanto,
    is_sdnq,
    is_torch_compile,
    is_torchao,
    require_accelerate,
    require_accelerator,
    require_auto_round_version_greater_or_equal,
    require_bitsandbytes_version_greater,
    require_gguf_version_greater_or_equal,
    require_modelopt_version_greater_or_equal,
    require_quanto,
    require_sdnq,
    require_torchao_version_greater_or_equal,
    torch_device,
)


if is_nvidia_modelopt_available():
    import modelopt.torch.quantization as mtq

if is_bitsandbytes_available():
    import bitsandbytes as bnb

if is_optimum_quanto_available():
    from optimum.quanto import QLinear

if is_gguf_available():
    pass

if is_torchao_available():
    import torchao.quantization as _torchao_quantization


class LoRALayer(torch.nn.Module):
    """Wraps a linear layer with LoRA-like adapter - Used for testing purposes only.

    Taken from
    https://github.com/huggingface/transformers/blob/566302686a71de14125717dea9a6a45b24d42b37/tests/quantization/bnb/test_4bit.py#L62C5-L78C77
    """

    def __init__(self, module: torch.nn.Module, rank: int):
        super().__init__()
        self.module = module
        self.adapter = torch.nn.Sequential(
            torch.nn.Linear(module.in_features, rank, bias=False),
            torch.nn.Linear(rank, module.out_features, bias=False),
        )
        small_std = (2.0 / (5 * min(module.in_features, module.out_features))) ** 0.5
        torch.nn.init.normal_(self.adapter[0].weight, std=small_std)
        torch.nn.init.zeros_(self.adapter[1].weight)
        self.adapter.to(module.weight.device)

    def forward(self, input, *args, **kwargs):
        return self.module(input, *args, **kwargs) + self.adapter(input)


@is_quantization
@require_accelerator
class QuantizationTesterMixin:
    """
    Base mixin class providing common test implementations for quantization testing.

    Backend-specific mixins should:
    1. Implement _create_quantized_model(config_kwargs)
    2. Implement _verify_if_layer_quantized(name, module, config_kwargs)
    3. Define their config dict (e.g., BNB_CONFIGS, QUANTO_WEIGHT_TYPES, etc.)
    4. Use @pytest.mark.parametrize to create tests that call the common test methods below

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained (e.g., {"subfolder": "transformer"})

    Expected methods in test classes:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass
    """

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

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

    def _create_quantized_model(self, config_kwargs, **extra_kwargs):
        """
        Create a quantized model with the given config kwargs.

        Args:
            config_kwargs: Quantization config parameters
            **extra_kwargs: Additional kwargs to pass to from_pretrained (e.g., device_map, offload_folder)
        """
        raise NotImplementedError("Subclass must implement _create_quantized_model")

    def _verify_if_layer_quantized(self, name, module, config_kwargs):
        raise NotImplementedError("Subclass must implement _verify_if_layer_quantized")

    def _is_module_quantized(self, module):
        """
        Check if a module is quantized. Returns True if quantized, False otherwise.
        Default implementation tries _verify_if_layer_quantized and catches exceptions.
        Subclasses can override for more efficient checking.
        """
        try:
            self._verify_if_layer_quantized("", module, {})
            return True
        except (AssertionError, AttributeError):
            return False

    def _load_unquantized_model(self):
        kwargs = getattr(self, "pretrained_model_kwargs", {})
        return self.model_class.from_pretrained(self.pretrained_model_name_or_path, **kwargs)

    def _test_quantization_num_parameters(self, config_kwargs):
        model = self._load_unquantized_model()
        num_params = model.num_parameters()

        model_quantized = self._create_quantized_model(config_kwargs)
        num_params_quantized = model_quantized.num_parameters()

        assert num_params == num_params_quantized, (
            f"Parameter count mismatch: unquantized={num_params}, quantized={num_params_quantized}"
        )

    def _test_quantization_memory_footprint(self, config_kwargs, expected_memory_reduction=1.2):
        model = self._load_unquantized_model()
        mem = model.get_memory_footprint()

        model_quantized = self._create_quantized_model(config_kwargs)
        mem_quantized = model_quantized.get_memory_footprint()

        ratio = mem / mem_quantized
        assert ratio >= expected_memory_reduction, (
            f"Memory ratio {ratio:.2f} is less than expected ({expected_memory_reduction}x). unquantized={mem}, quantized={mem_quantized}"
        )

    @torch.no_grad()
    def _test_quantization_inference(self, config_kwargs):
        model_quantized = self._create_quantized_model(config_kwargs)
        model_quantized.to(torch_device)

        inputs = self.get_dummy_inputs()
        output = model_quantized(**inputs, return_dict=False)[0]

        assert output is not None, "Model output is None"
        assert not torch.isnan(output).any(), "Model output contains NaN"

    def _test_quantization_dtype_assignment(self, config_kwargs):
        model = self._create_quantized_model(config_kwargs)

        with pytest.raises(ValueError):
            model.to(torch.float16)

        with pytest.raises(ValueError):
            device_0 = f"{torch_device}:0"
            model.to(device=device_0, dtype=torch.float16)

        with pytest.raises(ValueError):
            model.float()

        with pytest.raises(ValueError):
            model.half()

        model.to(torch_device)

    @torch.no_grad()
    def _test_quantization_lora_inference(self, config_kwargs):
        try:
            from peft import LoraConfig
        except ImportError:
            pytest.skip("peft is not available")

        from diffusers.loaders.peft import PeftAdapterMixin

        if not issubclass(self.model_class, PeftAdapterMixin):
            pytest.skip(f"PEFT is not supported for this model ({self.model_class.__name__})")

        model = self._create_quantized_model(config_kwargs)

        lora_config = LoraConfig(
            r=4,
            lora_alpha=4,
            target_modules=["to_q", "to_k", "to_v", "to_out.0"],
            init_lora_weights=False,
        )
        model.add_adapter(lora_config)
        # Move LoRA adapter weights to device (they default to CPU)
        model.to(torch_device)

        inputs = self.get_dummy_inputs()
        output = model(**inputs, return_dict=False)[0]

        assert output is not None, "Model output is None with LoRA"
        assert not torch.isnan(output).any(), "Model output contains NaN with LoRA"

    @torch.no_grad()
    def _test_quantization_serialization(self, config_kwargs, tmp_path, max_shard_size=None):
        """
        Test that a quantized model can be saved and reloaded without changing its outputs.

        Args:
            config_kwargs: Quantization config parameters
            tmp_path: Directory the model is serialized into
            max_shard_size: When set, the checkpoint is sharded and the shard/index files are checked
        """
        model = self._create_quantized_model(config_kwargs)
        model.to(torch_device)

        inputs = self.get_dummy_inputs()
        expected_output = model(**inputs, return_dict=False)[0].detach().cpu()

        save_kwargs = {"safe_serialization": True}
        if max_shard_size is not None:
            save_kwargs["max_shard_size"] = max_shard_size
        model.save_pretrained(str(tmp_path), **save_kwargs)

        del model
        gc.collect()
        backend_empty_cache(torch_device)

        if max_shard_size is not None:
            assert len(list(tmp_path.glob("*.safetensors"))) > 1, "Expected a sharded safe-serialization checkpoint."
            assert any(path.name.endswith(".index.json") for path in tmp_path.iterdir()), (
                "Expected an index file for sharded safe checkpoint."
            )

        model_loaded = self.model_class.from_pretrained(str(tmp_path), device_map=str(torch_device))

        output = model_loaded(**inputs, return_dict=False)[0].detach().cpu()
        assert_tensors_close(output, expected_output, rtol=1e-3, atol=1e-3)

    def _test_quantization_config_serialization(self, config_kwargs):
        """
        Test that the quantization config attached to a quantized model is serializable.

        Args:
            config_kwargs: Quantization config parameters
        """
        model = self._create_quantized_model(config_kwargs)

        assert "quantization_config" in model.config, "Missing quantization_config"
        _ = model.config["quantization_config"].to_dict()
        _ = model.config["quantization_config"].to_diff_dict()
        _ = model.config["quantization_config"].to_json_string()

    def _test_original_dtype(self, config_kwargs):
        """
        Test that the dtype the model had before quantization is recorded on its config.

        Args:
            config_kwargs: Quantization config parameters
        """
        model = self._create_quantized_model(config_kwargs)

        assert "_pre_quantization_dtype" in model.config, "Missing _pre_quantization_dtype"
        assert model.config["_pre_quantization_dtype"] in [
            torch.float16,
            torch.float32,
            torch.bfloat16,
        ], f"Unexpected dtype: {model.config['_pre_quantization_dtype']}"

    def _test_quantized_layers(self, config_kwargs):
        model_fp = self._load_unquantized_model()
        num_linear_layers = sum(1 for module in model_fp.modules() if isinstance(module, torch.nn.Linear))

        model_quantized = self._create_quantized_model(config_kwargs)

        num_fp32_modules = 0
        if hasattr(model_quantized, "_keep_in_fp32_modules") and model_quantized._keep_in_fp32_modules:
            for name, module in model_quantized.named_modules():
                if isinstance(module, torch.nn.Linear):
                    if any(fp32_name in name for fp32_name in model_quantized._keep_in_fp32_modules):
                        num_fp32_modules += 1

        expected_quantized_layers = num_linear_layers - num_fp32_modules

        num_quantized_layers = 0
        for name, module in model_quantized.named_modules():
            if isinstance(module, torch.nn.Linear):
                if hasattr(model_quantized, "_keep_in_fp32_modules") and model_quantized._keep_in_fp32_modules:
                    if any(fp32_name in name for fp32_name in model_quantized._keep_in_fp32_modules):
                        continue
                self._verify_if_layer_quantized(name, module, config_kwargs)
                num_quantized_layers += 1

        assert num_quantized_layers > 0, (
            f"No quantized layers found in model (expected {expected_quantized_layers} linear layers, {num_fp32_modules} kept in FP32)"
        )
        assert num_quantized_layers == expected_quantized_layers, (
            f"Quantized layer count mismatch: expected {expected_quantized_layers}, got {num_quantized_layers} (total linear layers: {num_linear_layers}, FP32 modules: {num_fp32_modules})"
        )

    def _test_keep_modules_in_fp32(self, config_kwargs):
        """
        Test that modules listed in the model's `_keep_in_fp32_modules` stay in FP32 after quantization.

        Args:
            config_kwargs: Quantization config parameters
        """
        fp32_modules = getattr(self.model_class, "_keep_in_fp32_modules", None)
        if not fp32_modules:
            pytest.skip(f"{self.model_class.__name__} does not declare _keep_in_fp32_modules")

        model = self._create_quantized_model(config_kwargs)
        model.to(torch_device)

        for name, module in model.named_modules():
            if isinstance(module, torch.nn.Linear) and any(fp32_name in name for fp32_name in fp32_modules):
                assert module.weight.dtype == torch.float32, (
                    f"Module {name} should be FP32 but is {module.weight.dtype}"
                )

    def _test_quantization_modules_to_not_convert(self, config_kwargs, modules_to_not_convert):
        """
        Test that modules specified in modules_to_not_convert are not quantized.

        Args:
            config_kwargs: Base quantization config kwargs
            modules_to_not_convert: List of module names to exclude from quantization
        """
        # Create config with modules_to_not_convert
        config_kwargs_with_exclusion = config_kwargs.copy()
        config_kwargs_with_exclusion["modules_to_not_convert"] = modules_to_not_convert

        model_with_exclusion = self._create_quantized_model(config_kwargs_with_exclusion)

        # Find a module that should NOT be quantized
        found_excluded = False
        for name, module in model_with_exclusion.named_modules():
            if isinstance(module, torch.nn.Linear):
                # Check if this module is in the exclusion list
                if any(excluded in name for excluded in modules_to_not_convert):
                    found_excluded = True
                    # This module should NOT be quantized
                    assert not self._is_module_quantized(module), (
                        f"Module {name} should not be quantized but was found to be quantized"
                    )

        assert found_excluded, f"No linear layers found in excluded modules: {modules_to_not_convert}"

        # Find a module that SHOULD be quantized (not in exclusion list)
        found_quantized = False
        for name, module in model_with_exclusion.named_modules():
            if isinstance(module, torch.nn.Linear):
                # Check if this module is NOT in the exclusion list
                if not any(excluded in name for excluded in modules_to_not_convert):
                    if self._is_module_quantized(module):
                        found_quantized = True
                        break

        assert found_quantized, "No quantized layers found outside of excluded modules"

        # Compare memory footprint with fully quantized model
        model_fully_quantized = self._create_quantized_model(config_kwargs)

        mem_with_exclusion = model_with_exclusion.get_memory_footprint()
        mem_fully_quantized = model_fully_quantized.get_memory_footprint()

        assert mem_with_exclusion > mem_fully_quantized, (
            f"Model with exclusions should be larger. With exclusion: {mem_with_exclusion}, fully quantized: {mem_fully_quantized}"
        )

    @torch.no_grad()
    def _test_quantization_device_map(self, config_kwargs):
        """
        Test that quantized models work correctly with device_map="auto".

        Args:
            config_kwargs: Base quantization config kwargs
        """
        model = self._create_quantized_model(config_kwargs, device_map="auto")

        assert hasattr(model, "hf_device_map"), "Model should have hf_device_map attribute"
        assert model.hf_device_map is not None, "hf_device_map should not be None"

        inputs = self.get_dummy_inputs()
        output = model(**inputs, return_dict=False)[0]
        assert output is not None, "Model output is None"
        assert not torch.isnan(output).any(), "Model output contains NaN"

    def _test_quantization_cpu_device_map(self, config_kwargs):
        """
        Test that quantized models are placed on the CPU with device_map="cpu".

        Args:
            config_kwargs: Base quantization config kwargs
        """
        model_quantized = self._create_quantized_model(config_kwargs, device_map="cpu")

        assert hasattr(model_quantized, "hf_device_map"), "Model should have hf_device_map attribute"
        assert model_quantized.hf_device_map is not None, "hf_device_map should not be None"
        assert model_quantized.device == torch.device("cpu"), (
            f"Model should be on CPU, but is on {model_quantized.device}"
        )

    @torch.no_grad()
    def _test_dequantize(self, config_kwargs):
        """
        Test that dequantize() converts quantized model back to standard linear layers.

        Args:
            config_kwargs: Quantization config parameters
        """
        model = self._create_quantized_model(config_kwargs)
        model.to(torch_device)

        if not hasattr(model, "dequantize"):
            pytest.skip("Model does not have dequantize method")

        model.dequantize()

        for name, module in model.named_modules():
            if isinstance(module, torch.nn.Linear):
                assert not self._is_module_quantized(module), f"Module {name} is still quantized after dequantize()"

        inputs = self.get_dummy_inputs()
        output = model(**inputs, return_dict=False)[0]
        assert output is not None, "Model output is None after dequantization"
        assert not torch.isnan(output).any(), "Model output contains NaN after dequantization"

    def _test_quantization_training(self, config_kwargs):
        """
        Test that quantized models can be used for training with LoRA-like adapters.

        This test:
        1. Freezes all model parameters
        2. Casts small parameters (e.g., layernorm) to fp32 for stability
        3. Adds LoRA adapters to attention layers
        4. Runs forward and backward passes
        5. Verifies gradients are computed correctly

        Args:
            config_kwargs: Quantization config parameters
        """
        model = self._create_quantized_model(config_kwargs)

        # Step 1: freeze all parameters
        for param in model.parameters():
            param.requires_grad = False
            if param.ndim == 1:
                # cast small parameters (e.g. layernorm) to fp32 for stability
                param.data = param.data.to(torch.float32)

        # Step 2: add adapters to attention layers
        adapter_count = 0
        for _, module in model.named_modules():
            if "Attention" in repr(type(module)):
                if hasattr(module, "to_k"):
                    module.to_k = LoRALayer(module.to_k, rank=4)
                    adapter_count += 1
                if hasattr(module, "to_q"):
                    module.to_q = LoRALayer(module.to_q, rank=4)
                    adapter_count += 1
                if hasattr(module, "to_v"):
                    module.to_v = LoRALayer(module.to_v, rank=4)
                    adapter_count += 1

        if adapter_count == 0:
            pytest.skip("No attention layers found in model for adapter training test")

        # Step 3: run forward and backward pass
        inputs = self.get_dummy_inputs()

        # Use bfloat16 on XPU to avoid gradient underflow with quantized layers
        autocast_dtype = torch.bfloat16 if torch_device == "xpu" else torch.float16
        with torch.amp.autocast(torch_device, dtype=autocast_dtype):
            out = model(**inputs, return_dict=False)[0]
            out.norm().backward()

        # Step 4: verify gradients are computed
        for module in model.modules():
            if isinstance(module, LoRALayer):
                assert module.adapter[1].weight.grad is not None, "LoRA adapter gradient is None"
                assert module.adapter[1].weight.grad.norm().item() > 0, "LoRA adapter gradient norm is zero"


@is_quantization
@is_bitsandbytes
@require_accelerator
@require_bitsandbytes_version_greater("0.43.2")
@require_accelerate
class BitsAndBytesConfigMixin:
    """
    Base mixin providing BitsAndBytes quantization config and model creation.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained
    """

    BNB_CONFIGS = {
        "4bit_nf4": {
            "load_in_4bit": True,
            "bnb_4bit_quant_type": "nf4",
            "bnb_4bit_compute_dtype": torch.float16,
        },
        "4bit_fp4": {
            "load_in_4bit": True,
            "bnb_4bit_quant_type": "fp4",
            "bnb_4bit_compute_dtype": torch.float16,
        },
        "8bit": {
            "load_in_8bit": True,
        },
    }

    BNB_EXPECTED_MEMORY_REDUCTIONS = {
        "4bit_nf4": 3.0,
        "4bit_fp4": 3.0,
        "8bit": 1.5,
    }

    def _create_quantized_model(self, config_kwargs, **extra_kwargs):
        config = BitsAndBytesConfig(**config_kwargs)
        kwargs = getattr(self, "pretrained_model_kwargs", {}).copy()
        kwargs["quantization_config"] = config
        kwargs.update(extra_kwargs)
        return self.model_class.from_pretrained(self.pretrained_model_name_or_path, **kwargs)

    def _verify_if_layer_quantized(self, name, module, config_kwargs):
        expected_weight_class = bnb.nn.Params4bit if config_kwargs.get("load_in_4bit") else bnb.nn.Int8Params
        assert module.weight.__class__ == expected_weight_class, (
            f"Layer {name} has weight type {module.weight.__class__}, expected {expected_weight_class}"
        )


@is_bitsandbytes
@require_accelerator
@require_bitsandbytes_version_greater("0.43.2")
@require_accelerate
class BitsAndBytesTesterMixin(BitsAndBytesConfigMixin, QuantizationTesterMixin):
    """
    Mixin class for testing BitsAndBytes quantization on models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained (e.g., {"subfolder": "transformer"})

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Optional class attributes:
        - BNB_CONFIGS: Dict of config name -> BitsAndBytesConfig kwargs to test

    Pytest mark: bitsandbytes
        Use `pytest -m "not bitsandbytes"` to skip these tests
    """

    @pytest.mark.parametrize(
        "config_name",
        list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
        ids=list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
    )
    def test_bnb_quantization_num_parameters(self, config_name):
        self._test_quantization_num_parameters(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])

    @pytest.mark.parametrize(
        "config_name",
        list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
        ids=list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
    )
    def test_bnb_quantization_memory_footprint(self, config_name):
        expected = BitsAndBytesConfigMixin.BNB_EXPECTED_MEMORY_REDUCTIONS.get(config_name, 1.2)
        self._test_quantization_memory_footprint(
            BitsAndBytesConfigMixin.BNB_CONFIGS[config_name], expected_memory_reduction=expected
        )

    @pytest.mark.parametrize(
        "config_name",
        list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
        ids=list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
    )
    def test_bnb_quantization_inference(self, config_name):
        self._test_quantization_inference(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])

    @pytest.mark.parametrize("config_name", ["4bit_nf4"], ids=["4bit_nf4"])
    def test_bnb_quantization_dtype_assignment(self, config_name):
        self._test_quantization_dtype_assignment(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])

    @pytest.mark.parametrize("config_name", ["4bit_nf4"], ids=["4bit_nf4"])
    def test_bnb_quantization_lora_inference(self, config_name):
        self._test_quantization_lora_inference(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])

    @pytest.mark.parametrize("config_name", ["4bit_nf4"], ids=["4bit_nf4"])
    def test_bnb_quantization_serialization(self, config_name, tmp_path):
        self._test_quantization_serialization(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name], tmp_path)

    @pytest.mark.parametrize(
        "config_name",
        list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
        ids=list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
    )
    def test_bnb_quantized_layers(self, config_name):
        self._test_quantized_layers(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])

    @pytest.mark.parametrize(
        "config_name",
        list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
        ids=list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
    )
    def test_bnb_quantization_config_serialization(self, config_name):
        self._test_quantization_config_serialization(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])

    def test_bnb_original_dtype(self):
        self._test_original_dtype(BitsAndBytesConfigMixin.BNB_CONFIGS["4bit_nf4"])

    def test_bnb_keep_modules_in_fp32(self):
        self._test_keep_modules_in_fp32(BitsAndBytesConfigMixin.BNB_CONFIGS["4bit_nf4"])

    def test_bnb_modules_to_not_convert(self):
        """Test that modules_to_not_convert parameter works correctly."""
        modules_to_exclude = getattr(self, "modules_to_not_convert_for_test", None)
        if modules_to_exclude is None:
            pytest.skip("modules_to_not_convert_for_test not defined for this model")

        self._test_quantization_modules_to_not_convert(
            BitsAndBytesConfigMixin.BNB_CONFIGS["4bit_nf4"], modules_to_exclude
        )

    @pytest.mark.parametrize("config_name", ["4bit_nf4", "8bit"], ids=["4bit_nf4", "8bit"])
    def test_bnb_device_map(self, config_name):
        """Test that device_map='auto' works correctly with quantization."""
        self._test_quantization_device_map(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])

    def test_bnb_dequantize(self):
        """Test that dequantize() works correctly."""
        self._test_dequantize(BitsAndBytesConfigMixin.BNB_CONFIGS["4bit_nf4"])

    def test_bnb_training(self):
        """Test that quantized models can be used for training with adapters."""
        self._test_quantization_training(BitsAndBytesConfigMixin.BNB_CONFIGS["4bit_nf4"])

    @pytest.mark.parametrize(
        "config_name",
        list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
        ids=list(BitsAndBytesConfigMixin.BNB_CONFIGS.keys()),
    )
    def test_bnb_cpu_device_map(self, config_name):
        """Test that device_map='cpu' works correctly with quantization."""
        self._test_quantization_cpu_device_map(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])


@is_quantization
@is_quanto
@require_quanto
@require_accelerate
@require_accelerator
class QuantoConfigMixin:
    """
    Base mixin providing Quanto quantization config and model creation.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained
    """

    QUANTO_WEIGHT_TYPES = {
        "float8": {"weights_dtype": "float8"},
        "int8": {"weights_dtype": "int8"},
        "int4": {"weights_dtype": "int4"},
        "int2": {"weights_dtype": "int2"},
    }

    QUANTO_EXPECTED_MEMORY_REDUCTIONS = {
        "float8": 1.5,
        "int8": 1.5,
        "int4": 3.0,
        "int2": 7.0,
    }

    def _create_quantized_model(self, config_kwargs, **extra_kwargs):
        config = QuantoConfig(**config_kwargs)
        kwargs = getattr(self, "pretrained_model_kwargs", {}).copy()
        kwargs["quantization_config"] = config
        kwargs.update(extra_kwargs)
        return self.model_class.from_pretrained(self.pretrained_model_name_or_path, **kwargs)

    def _verify_if_layer_quantized(self, name, module, config_kwargs):
        assert isinstance(module, QLinear), f"Layer {name} is not QLinear, got {type(module)}"

    def _test_quantization_memory_footprint(self, config_kwargs, expected_memory_reduction=1.2):
        """Override to use max_memory_allocated for Quanto (get_memory_footprint doesn't reflect quantized _data)."""
        # Measure unquantized model memory
        backend_reset_peak_memory_stats(torch_device)
        backend_empty_cache(torch_device)

        model = self._load_unquantized_model()
        model.to(torch_device)
        mem = backend_max_memory_allocated(torch_device)

        del model
        gc.collect()
        backend_empty_cache(torch_device)

        # Measure quantized model memory
        backend_reset_peak_memory_stats(torch_device)

        model_quantized = self._create_quantized_model(config_kwargs)
        model_quantized.to(torch_device)
        mem_quantized = backend_max_memory_allocated(torch_device)

        ratio = mem / mem_quantized
        assert ratio >= expected_memory_reduction, (
            f"Memory ratio {ratio:.2f} is less than expected ({expected_memory_reduction}x). unquantized={mem}, quantized={mem_quantized}"
        )


@is_quanto
@require_quanto
@require_accelerate
@require_accelerator
class QuantoTesterMixin(QuantoConfigMixin, QuantizationTesterMixin):
    """
    Mixin class for testing Quanto quantization on models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained (e.g., {"subfolder": "transformer"})

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Optional class attributes:
        - QUANTO_WEIGHT_TYPES: Dict of weight_type_name -> qtype

    Pytest mark: quanto
        Use `pytest -m "not quanto"` to skip these tests
    """

    @pytest.mark.parametrize(
        "weight_type_name",
        list(QuantoConfigMixin.QUANTO_WEIGHT_TYPES.keys()),
        ids=list(QuantoConfigMixin.QUANTO_WEIGHT_TYPES.keys()),
    )
    def test_quanto_quantization_num_parameters(self, weight_type_name):
        self._test_quantization_num_parameters(QuantoConfigMixin.QUANTO_WEIGHT_TYPES[weight_type_name])

    @pytest.mark.parametrize(
        "weight_type_name",
        list(QuantoConfigMixin.QUANTO_WEIGHT_TYPES.keys()),
        ids=list(QuantoConfigMixin.QUANTO_WEIGHT_TYPES.keys()),
    )
    def test_quanto_quantization_memory_footprint(self, weight_type_name):
        expected = QuantoConfigMixin.QUANTO_EXPECTED_MEMORY_REDUCTIONS.get(weight_type_name, 1.2)
        self._test_quantization_memory_footprint(
            QuantoConfigMixin.QUANTO_WEIGHT_TYPES[weight_type_name], expected_memory_reduction=expected
        )

    @pytest.mark.parametrize(
        "weight_type_name",
        list(QuantoConfigMixin.QUANTO_WEIGHT_TYPES.keys()),
        ids=list(QuantoConfigMixin.QUANTO_WEIGHT_TYPES.keys()),
    )
    def test_quanto_quantization_inference(self, weight_type_name):
        self._test_quantization_inference(QuantoConfigMixin.QUANTO_WEIGHT_TYPES[weight_type_name])

    @pytest.mark.parametrize("weight_type_name", ["int8"], ids=["int8"])
    def test_quanto_quantized_layers(self, weight_type_name):
        self._test_quantized_layers(QuantoConfigMixin.QUANTO_WEIGHT_TYPES[weight_type_name])

    @pytest.mark.parametrize("weight_type_name", ["int8"], ids=["int8"])
    def test_quanto_quantization_lora_inference(self, weight_type_name):
        self._test_quantization_lora_inference(QuantoConfigMixin.QUANTO_WEIGHT_TYPES[weight_type_name])

    @pytest.mark.parametrize("weight_type_name", ["int8"], ids=["int8"])
    def test_quanto_quantization_serialization(self, weight_type_name, tmp_path):
        self._test_quantization_serialization(QuantoConfigMixin.QUANTO_WEIGHT_TYPES[weight_type_name], tmp_path)

    def test_quanto_modules_to_not_convert(self):
        """Test that modules_to_not_convert parameter works correctly."""
        modules_to_exclude = getattr(self, "modules_to_not_convert_for_test", None)
        if modules_to_exclude is None:
            pytest.skip("modules_to_not_convert_for_test not defined for this model")

        self._test_quantization_modules_to_not_convert(
            QuantoConfigMixin.QUANTO_WEIGHT_TYPES["int8"], modules_to_exclude
        )

    def test_quanto_device_map(self):
        """Test that device_map='auto' works correctly with quantization."""
        self._test_quantization_device_map(QuantoConfigMixin.QUANTO_WEIGHT_TYPES["int8"])

    def test_quanto_dequantize(self):
        """Test that dequantize() works correctly."""
        self._test_dequantize(QuantoConfigMixin.QUANTO_WEIGHT_TYPES["int8"])


@is_quantization
@is_torchao
@require_accelerator
@require_torchao_version_greater_or_equal("0.7.0")
class TorchAoConfigMixin:
    """
    Base mixin providing TorchAO quantization config and model creation.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained
    """

    TORCHAO_QUANT_TYPES = {
        "int4wo": "Int4WeightOnlyConfig",
        "int8wo": "Int8WeightOnlyConfig",
        "int8dq": "Int8DynamicActivationInt8WeightConfig",
    }

    TORCHAO_EXPECTED_MEMORY_REDUCTIONS = {
        "int4wo": 1.8,
        "int8wo": 1.5,
        "int8dq": 1.5,
    }

    @staticmethod
    def _get_quant_config(config_name, modules_to_not_convert=None):
        config_cls = getattr(_torchao_quantization, config_name)
        config_kwargs = {"version": 2}
        # version=2 int4 defaults to the "plain" packing format, which routes through the
        # fbgemm/mslk Int4Tensor kernels. Pin the packing format to the tinygemm
        # (_convert_weight_to_int4pack) path on CUDA and plain_int32 on Intel XPU so the tests
        # don't require those extra kernels to be installed.
        if config_name == "Int4WeightOnlyConfig":
            if torch_device == "xpu":
                config_kwargs["int4_packing_format"] = "plain_int32"
            elif torch_device == "cuda":
                config_kwargs["int4_packing_format"] = "tile_packed_to_4d"

        return TorchAoConfig(config_cls(**config_kwargs), modules_to_not_convert=modules_to_not_convert)

    def _create_quantized_model(self, config_name, modules_to_not_convert=None, **extra_kwargs):
        config = self._get_quant_config(config_name, modules_to_not_convert=modules_to_not_convert)
        kwargs = getattr(self, "pretrained_model_kwargs", {}).copy()
        kwargs["quantization_config"] = config
        kwargs["device_map"] = str(torch_device)
        kwargs.update(extra_kwargs)
        return self.model_class.from_pretrained(self.pretrained_model_name_or_path, **kwargs)

    def _verify_if_layer_quantized(self, name, module, config_kwargs):
        from torchao.utils import TorchAOBaseTensor

        assert isinstance(module, torch.nn.Linear), f"Layer {name} is not Linear, got {type(module)}"
        assert isinstance(module.weight, TorchAOBaseTensor), (
            f"Layer {name} weight is {type(module.weight)}, expected TorchAOBaseTensor"
        )


# int4wo requires CUDA or XPU ops (_convert_weight_to_int4pack)
_int4wo_skip = pytest.mark.skipif(
    torch_device not in ["cuda", "xpu"], reason="int4wo quantization requires CUDA or XPU"
)

# The CUDA int4 tinygemm path (Int4TilePackedTo4dTensor) does not implement aten.dequantize.
_int4wo_dequantize_skip = pytest.mark.skip(
    reason="int4wo tinygemm packing (Int4TilePackedTo4dTensor) does not support dequantize"
)


@is_torchao
@require_accelerator
@require_torchao_version_greater_or_equal("0.7.0")
class TorchAoTesterMixin(TorchAoConfigMixin, QuantizationTesterMixin):
    """
    Mixin class for testing TorchAO quantization on models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained (e.g., {"subfolder": "transformer"})

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Optional class attributes:
        - TORCHAO_QUANT_TYPES: Dict of quantization type strings to test

    Pytest mark: torchao
        Use `pytest -m "not torchao"` to skip these tests
    """

    @pytest.mark.parametrize(
        "quant_type",
        [
            pytest.param("int4wo", marks=_int4wo_skip),
            "int8wo",
            "int8dq",
        ],
        ids=["int4wo", "int8wo", "int8dq"],
    )
    def test_torchao_quantization_num_parameters(self, quant_type):
        self._test_quantization_num_parameters(TorchAoConfigMixin.TORCHAO_QUANT_TYPES[quant_type])

    @pytest.mark.parametrize(
        "quant_type",
        [
            pytest.param("int4wo", marks=_int4wo_skip),
            "int8wo",
            "int8dq",
        ],
        ids=["int4wo", "int8wo", "int8dq"],
    )
    def test_torchao_quantization_memory_footprint(self, quant_type):
        expected = TorchAoConfigMixin.TORCHAO_EXPECTED_MEMORY_REDUCTIONS.get(quant_type, 1.2)
        self._test_quantization_memory_footprint(
            TorchAoConfigMixin.TORCHAO_QUANT_TYPES[quant_type], expected_memory_reduction=expected
        )

    @pytest.mark.parametrize(
        "quant_type",
        [
            pytest.param("int4wo", marks=[_int4wo_skip, _int4wo_dequantize_skip]),
            "int8wo",
            "int8dq",
        ],
        ids=["int4wo", "int8wo", "int8dq"],
    )
    def test_torchao_quantization_inference(self, quant_type):
        self._test_quantization_inference(TorchAoConfigMixin.TORCHAO_QUANT_TYPES[quant_type])

    @pytest.mark.parametrize("quant_type", ["int8wo"], ids=["int8wo"])
    def test_torchao_quantized_layers(self, quant_type):
        self._test_quantized_layers(TorchAoConfigMixin.TORCHAO_QUANT_TYPES[quant_type])

    @pytest.mark.parametrize("quant_type", ["int8wo"], ids=["int8wo"])
    def test_torchao_quantization_lora_inference(self, quant_type):
        self._test_quantization_lora_inference(TorchAoConfigMixin.TORCHAO_QUANT_TYPES[quant_type])

    @pytest.mark.parametrize("quant_type", ["int8wo"], ids=["int8wo"])
    @require_torchao_version_greater_or_equal("0.16.0")
    def test_torchao_quantization_serialization(self, quant_type, tmp_path):
        self._test_quantization_serialization(TorchAoConfigMixin.TORCHAO_QUANT_TYPES[quant_type], tmp_path)

    @pytest.mark.parametrize("quant_type", ["int8dq"], ids=["int8dq"])
    @require_torchao_version_greater_or_equal("0.16.0")
    def test_torchao_quantization_sharded_serialization(self, quant_type, tmp_path):
        self._test_quantization_serialization(
            TorchAoConfigMixin.TORCHAO_QUANT_TYPES[quant_type], tmp_path, max_shard_size="16KB"
        )

    def test_torchao_modules_to_not_convert(self):
        """Test that modules_to_not_convert parameter works correctly."""
        modules_to_exclude = getattr(self, "modules_to_not_convert_for_test", None)
        if modules_to_exclude is None:
            pytest.skip("modules_to_not_convert_for_test not defined for this model")

        # TorchAoConfig takes modules_to_not_convert directly (not inside the quant_type config),
        # so this can't reuse the dict-based QuantizationTesterMixin helper.
        model = self._create_quantized_model(
            TorchAoConfigMixin.TORCHAO_QUANT_TYPES["int8wo"], modules_to_not_convert=modules_to_exclude
        )

        found_excluded = False
        for name, module in model.named_modules():
            if isinstance(module, torch.nn.Linear) and any(excluded in name for excluded in modules_to_exclude):
                found_excluded = True
                assert not self._is_module_quantized(module), (
                    f"Module {name} should not be quantized but was found to be quantized"
                )

        assert found_excluded, f"No linear layers found in excluded modules: {modules_to_exclude}"

    def test_torchao_device_map(self):
        """Test that device_map='auto' works correctly with quantization."""
        self._test_quantization_device_map(TorchAoConfigMixin.TORCHAO_QUANT_TYPES["int8wo"])

    def test_torchao_dequantize(self):
        """Test that dequantize() works correctly."""
        self._test_dequantize(TorchAoConfigMixin.TORCHAO_QUANT_TYPES["int8wo"])

    def test_torchao_training(self):
        """Test that quantized models can be used for training with adapters."""
        self._test_quantization_training(TorchAoConfigMixin.TORCHAO_QUANT_TYPES["int8wo"])

    def test_torchao_keep_modules_in_fp32(self):
        self._test_keep_modules_in_fp32(TorchAoConfigMixin.TORCHAO_QUANT_TYPES["int8wo"])


@is_quantization
@is_gguf
@require_accelerate
@require_accelerator
@require_gguf_version_greater_or_equal("0.10.0")
class GGUFConfigMixin:
    """
    Base mixin providing GGUF quantization config and model creation.

    Expected from config mixin:
        - model_class: The model class to test

    Required properties (must be implemented by subclasses):
        - gguf_filename: URL or path to the GGUF file
    """

    @property
    def gguf_filename(self):
        """URL or path to the GGUF file. Must be implemented by subclasses."""
        raise NotImplementedError("Subclasses must implement the `gguf_filename` property.")

    def _create_quantized_model(self, config_kwargs=None, **extra_kwargs):
        if config_kwargs is None:
            config_kwargs = {"compute_dtype": torch.bfloat16}

        config = GGUFQuantizationConfig(**config_kwargs)
        kwargs = {
            "quantization_config": config,
            "torch_dtype": config_kwargs.get("compute_dtype", torch.bfloat16),
            "device_map": str(torch_device),
        }
        kwargs.update(extra_kwargs)
        return self.model_class.from_single_file(self.gguf_filename, **kwargs)

    def _verify_if_layer_quantized(self, name, module, config_kwargs=None):
        from diffusers.quantizers.gguf.utils import GGUFParameter

        assert isinstance(module.weight, GGUFParameter), f"{name} weight is not GGUFParameter"
        assert hasattr(module.weight, "quant_type"), f"{name} weight missing quant_type"
        assert module.weight.dtype == torch.uint8, f"{name} weight dtype should be uint8"


@is_gguf
@require_accelerate
@require_accelerator
@require_gguf_version_greater_or_equal("0.10.0")
class GGUFTesterMixin(GGUFConfigMixin, QuantizationTesterMixin):
    """
    Mixin class for testing GGUF quantization on models.

    Expected from config mixin:
        - model_class: The model class to test

    Required properties (must be implemented by subclasses):
        - gguf_filename: URL or path to the GGUF file

    Expected methods from config mixin:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Pytest mark: gguf
        Use `pytest -m "not gguf"` to skip these tests
    """

    def test_gguf_quantization_inference(self):
        self._test_quantization_inference({"compute_dtype": torch.bfloat16})

    def test_gguf_keep_modules_in_fp32(self):
        if not hasattr(self.model_class, "_keep_in_fp32_modules"):
            pytest.skip(f"{self.model_class.__name__} does not have _keep_in_fp32_modules")

        _keep_in_fp32_modules = self.model_class._keep_in_fp32_modules
        self.model_class._keep_in_fp32_modules = ["proj_out"]

        try:
            self._test_keep_modules_in_fp32({"compute_dtype": torch.bfloat16})
        finally:
            self.model_class._keep_in_fp32_modules = _keep_in_fp32_modules

    def test_gguf_quantization_dtype_assignment(self):
        self._test_quantization_dtype_assignment({"compute_dtype": torch.bfloat16})

    def test_gguf_quantization_lora_inference(self):
        self._test_quantization_lora_inference({"compute_dtype": torch.bfloat16})

    def test_gguf_dequantize(self):
        """Test that dequantize() works correctly."""
        self._test_dequantize({"compute_dtype": torch.bfloat16})


@is_quantization
@is_modelopt
@require_accelerator
@require_accelerate
@require_modelopt_version_greater_or_equal("0.33.1")
class ModelOptConfigMixin:
    """
    Base mixin providing NVIDIA ModelOpt quantization config and model creation.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained
    """

    MODELOPT_CONFIGS = {
        "fp8": {"quant_type": "FP8"},
        "int8": {"quant_type": "INT8"},
        "int4": {"quant_type": "INT4"},
    }

    MODELOPT_EXPECTED_MEMORY_REDUCTIONS = {
        "fp8": 1.5,
        "int8": 1.5,
        "int4": 3.0,
    }

    def _create_quantized_model(self, config_kwargs, **extra_kwargs):
        config = NVIDIAModelOptConfig(**config_kwargs)
        kwargs = getattr(self, "pretrained_model_kwargs", {}).copy()
        kwargs["quantization_config"] = config
        kwargs["device_map"] = str(torch_device)
        kwargs.update(extra_kwargs)
        return self.model_class.from_pretrained(self.pretrained_model_name_or_path, **kwargs)

    def _verify_if_layer_quantized(self, name, module, config_kwargs):
        assert mtq.utils.is_quantized(module), f"Layer {name} does not have weight_quantizer attribute (not quantized)"


@is_modelopt
@require_accelerator
@require_accelerate
@require_modelopt_version_greater_or_equal("0.33.1")
class ModelOptTesterMixin(ModelOptConfigMixin, QuantizationTesterMixin):
    """
    Mixin class for testing NVIDIA ModelOpt quantization on models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained (e.g., {"subfolder": "transformer"})

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Optional class attributes:
        - MODELOPT_CONFIGS: Dict of config name -> NVIDIAModelOptConfig kwargs to test

    Pytest mark: modelopt
        Use `pytest -m "not modelopt"` to skip these tests
    """

    @pytest.mark.parametrize("config_name", ["fp8"], ids=["fp8"])
    def test_modelopt_quantization_num_parameters(self, config_name):
        self._test_quantization_num_parameters(ModelOptConfigMixin.MODELOPT_CONFIGS[config_name])

    @pytest.mark.parametrize(
        "config_name",
        list(ModelOptConfigMixin.MODELOPT_CONFIGS.keys()),
        ids=list(ModelOptConfigMixin.MODELOPT_CONFIGS.keys()),
    )
    def test_modelopt_quantization_memory_footprint(self, config_name):
        expected = ModelOptConfigMixin.MODELOPT_EXPECTED_MEMORY_REDUCTIONS.get(config_name, 1.2)
        self._test_quantization_memory_footprint(
            ModelOptConfigMixin.MODELOPT_CONFIGS[config_name], expected_memory_reduction=expected
        )

    @pytest.mark.parametrize(
        "config_name",
        list(ModelOptConfigMixin.MODELOPT_CONFIGS.keys()),
        ids=list(ModelOptConfigMixin.MODELOPT_CONFIGS.keys()),
    )
    def test_modelopt_quantization_inference(self, config_name):
        self._test_quantization_inference(ModelOptConfigMixin.MODELOPT_CONFIGS[config_name])

    @pytest.mark.parametrize("config_name", ["fp8"], ids=["fp8"])
    def test_modelopt_quantization_dtype_assignment(self, config_name):
        self._test_quantization_dtype_assignment(ModelOptConfigMixin.MODELOPT_CONFIGS[config_name])

    @pytest.mark.parametrize("config_name", ["fp8"], ids=["fp8"])
    def test_modelopt_quantization_lora_inference(self, config_name):
        self._test_quantization_lora_inference(ModelOptConfigMixin.MODELOPT_CONFIGS[config_name])

    @pytest.mark.parametrize("config_name", ["fp8"], ids=["fp8"])
    def test_modelopt_quantization_serialization(self, config_name, tmp_path):
        self._test_quantization_serialization(ModelOptConfigMixin.MODELOPT_CONFIGS[config_name], tmp_path)

    @pytest.mark.parametrize("config_name", ["fp8"], ids=["fp8"])
    def test_modelopt_quantized_layers(self, config_name):
        self._test_quantized_layers(ModelOptConfigMixin.MODELOPT_CONFIGS[config_name])

    def test_modelopt_modules_to_not_convert(self):
        """Test that modules_to_not_convert parameter works correctly."""
        modules_to_exclude = getattr(self, "modules_to_not_convert_for_test", None)
        if modules_to_exclude is None:
            pytest.skip("modules_to_not_convert_for_test not defined for this model")

        self._test_quantization_modules_to_not_convert(ModelOptConfigMixin.MODELOPT_CONFIGS["fp8"], modules_to_exclude)

    def test_modelopt_device_map(self):
        """Test that device_map='auto' works correctly with quantization."""
        self._test_quantization_device_map(ModelOptConfigMixin.MODELOPT_CONFIGS["fp8"])

    def test_modelopt_dequantize(self):
        """Test that dequantize() works correctly."""
        self._test_dequantize(ModelOptConfigMixin.MODELOPT_CONFIGS["fp8"])


@is_quantization
@is_sdnq
@require_sdnq
@require_accelerate
@require_accelerator
class SDNQConfigMixin:
    """
    Base mixin providing SDNQ quantization config and model creation.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained
    """

    SDNQ_CONFIGS = {
        "int8": {"weights_dtype": "int8"},
        "uint4_svd": {"weights_dtype": "uint4", "use_svd": True},
    }

    SDNQ_EXPECTED_MEMORY_REDUCTIONS = {
        "int8": 1.5,
        "uint4_svd": 1.5,
    }

    def _create_quantized_model(self, config_kwargs, **extra_kwargs):
        config = SDNQConfig(**config_kwargs)
        kwargs = getattr(self, "pretrained_model_kwargs", {}).copy()
        kwargs["quantization_config"] = config
        # SDNQ leaves some modules (embedders, norms) unquantized, so the compute dtype must be set at load
        # time to keep them consistent with the quantized layers.
        kwargs.setdefault("dtype", getattr(self, "torch_dtype", torch.bfloat16))
        kwargs.update(extra_kwargs)
        return self.model_class.from_pretrained(self.pretrained_model_name_or_path, **kwargs)

    def _verify_if_layer_quantized(self, name, module, config_kwargs):
        assert hasattr(module, "sdnq_dequantizer"), f"Layer {name} is not an SDNQ quantized layer"


@is_sdnq
@require_sdnq
@require_accelerate
@require_accelerator
class SDNQTesterMixin(SDNQConfigMixin, QuantizationTesterMixin):
    """
    Mixin class for testing SDNQ quantization on models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained (e.g., {"subfolder": "transformer"})

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Optional class attributes:
        - SDNQ_CONFIGS: Dict of config name -> SDNQConfig kwargs to test

    Pytest mark: sdnq
        Use `pytest -m "not sdnq"` to skip these tests
    """

    @pytest.mark.parametrize(
        "config_name",
        list(SDNQConfigMixin.SDNQ_CONFIGS.keys()),
        ids=list(SDNQConfigMixin.SDNQ_CONFIGS.keys()),
    )
    def test_sdnq_quantization_inference(self, config_name):
        self._test_quantization_inference(SDNQConfigMixin.SDNQ_CONFIGS[config_name])

    @pytest.mark.parametrize(
        "config_name",
        list(SDNQConfigMixin.SDNQ_CONFIGS.keys()),
        ids=list(SDNQConfigMixin.SDNQ_CONFIGS.keys()),
    )
    def test_sdnq_quantization_memory_footprint(self, config_name):
        expected = SDNQConfigMixin.SDNQ_EXPECTED_MEMORY_REDUCTIONS.get(config_name, 1.2)
        self._test_quantization_memory_footprint(
            SDNQConfigMixin.SDNQ_CONFIGS[config_name], expected_memory_reduction=expected
        )

    @torch.no_grad()
    def test_sdnq_quantization_serialization(self, tmp_path):
        # Unlike the base helper, reload onto the accelerator: SDNQ reloads to CPU, while dummy inputs live on device.
        model = self._create_quantized_model(SDNQConfigMixin.SDNQ_CONFIGS["int8"])
        model.save_pretrained(str(tmp_path), safe_serialization=True)

        # No quantization_config passed, so it must be picked up from the saved config.json.
        model_loaded = self.model_class.from_pretrained(str(tmp_path)).to(torch_device)

        inputs = self.get_dummy_inputs()
        output = model_loaded(**inputs, return_dict=False)[0]
        assert not torch.isnan(output).any(), "Loaded model output contains NaN"

    @pytest.mark.parametrize("config_name", ["int8"], ids=["int8"])
    def test_sdnq_quantization_dtype_assignment(self, config_name):
        self._test_quantization_dtype_assignment(SDNQConfigMixin.SDNQ_CONFIGS[config_name])

    def test_sdnq_modules_to_not_convert(self):
        """Test that modules_to_not_convert parameter works correctly."""
        modules_to_exclude = getattr(self, "modules_to_not_convert_for_test", None)
        if modules_to_exclude is None:
            pytest.skip("modules_to_not_convert_for_test not defined for this model")

        self._test_quantization_modules_to_not_convert(SDNQConfigMixin.SDNQ_CONFIGS["int8"], modules_to_exclude)

    def test_sdnq_dequantize(self):
        """Test that dequantize() works correctly."""
        self._test_dequantize(SDNQConfigMixin.SDNQ_CONFIGS["int8"])


@is_quantization
@is_torch_compile
class QuantizationCompileTesterMixin:
    """
    Base mixin class providing common test implementations for torch.compile with quantized models.

    Backend-specific compile mixins should:
    1. Inherit from their respective config mixin (e.g., BitsAndBytesConfigMixin)
    2. Inherit from this mixin
    3. Define the config to use for compile tests

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained

    Expected methods in test classes:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass
    """

    def setup_method(self):
        gc.collect()
        backend_empty_cache(torch_device)
        torch.compiler.reset()

    def teardown_method(self):
        gc.collect()
        backend_empty_cache(torch_device)
        torch.compiler.reset()

    @torch.no_grad()
    def _test_torch_compile(self, config_kwargs, fullgraph=True, error_on_recompile=True):
        """
        Test that torch.compile works correctly with a quantized model.

        Args:
            config_kwargs: Quantization config parameters
            fullgraph: Whether the compiled model is required to compile without graph breaks
            error_on_recompile: Whether a recompilation during the forward pass should fail the test
        """
        model = self._create_quantized_model(config_kwargs)
        model.to(torch_device)
        model.eval()

        model.compile(fullgraph=fullgraph)

        with torch._dynamo.config.patch(error_on_recompile=error_on_recompile):
            inputs = self.get_dummy_inputs()
            output = model(**inputs, return_dict=False)[0]
            assert output is not None, "Model output is None"
            assert not torch.isnan(output).any(), "Model output contains NaN"

    @torch.no_grad()
    def _test_torch_compile_with_group_offload(self, config_kwargs, use_stream=False):
        """
        Test that torch.compile works correctly with a quantized model and group offloading.

        Args:
            config_kwargs: Quantization config parameters
            use_stream: Whether to use CUDA streams for offloading
        """
        torch._dynamo.config.cache_size_limit = 1000

        model = self._create_quantized_model(config_kwargs)
        model.eval()

        if not hasattr(model, "enable_group_offload"):
            pytest.skip("Model does not support group offloading")

        group_offload_kwargs = {
            "onload_device": torch.device(torch_device),
            "offload_device": torch.device("cpu"),
            "offload_type": "leaf_level",
            "use_stream": use_stream,
        }
        model.enable_group_offload(**group_offload_kwargs)
        model.compile()

        inputs = self.get_dummy_inputs()
        output = model(**inputs, return_dict=False)[0]
        assert output is not None, "Model output is None"
        assert not torch.isnan(output).any(), "Model output contains NaN"


@is_bitsandbytes
@require_accelerator
@require_bitsandbytes_version_greater("0.43.2")
@require_accelerate
class BitsAndBytesCompileTesterMixin(BitsAndBytesConfigMixin, QuantizationCompileTesterMixin):
    """
    Mixin class for testing torch.compile with BitsAndBytes quantized models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Pytest mark: bitsandbytes
        Use `pytest -m "not bitsandbytes"` to skip these tests
    """

    @pytest.mark.parametrize("config_name", ["4bit_nf4"], ids=["4bit_nf4"])
    def test_bnb_torch_compile(self, config_name):
        self._test_torch_compile(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])

    @pytest.mark.parametrize("config_name", ["4bit_nf4"], ids=["4bit_nf4"])
    def test_bnb_torch_compile_with_group_offload(self, config_name):
        self._test_torch_compile_with_group_offload(BitsAndBytesConfigMixin.BNB_CONFIGS[config_name])


@is_quanto
@require_quanto
@require_accelerate
@require_accelerator
class QuantoCompileTesterMixin(QuantoConfigMixin, QuantizationCompileTesterMixin):
    """
    Mixin class for testing torch.compile with Quanto quantized models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Pytest mark: quanto
        Use `pytest -m "not quanto"` to skip these tests
    """

    @pytest.mark.parametrize("weight_type_name", ["int8"], ids=["int8"])
    def test_quanto_torch_compile(self, weight_type_name):
        self._test_torch_compile(QuantoConfigMixin.QUANTO_WEIGHT_TYPES[weight_type_name])

    @pytest.mark.parametrize("weight_type_name", ["int8"], ids=["int8"])
    def test_quanto_torch_compile_with_group_offload(self, weight_type_name):
        self._test_torch_compile_with_group_offload(QuantoConfigMixin.QUANTO_WEIGHT_TYPES[weight_type_name])


@is_torchao
@require_accelerator
@require_torchao_version_greater_or_equal("0.7.0")
class TorchAoCompileTesterMixin(TorchAoConfigMixin, QuantizationCompileTesterMixin):
    """
    Mixin class for testing torch.compile with TorchAO quantized models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Pytest mark: torchao
        Use `pytest -m "not torchao"` to skip these tests
    """

    @pytest.mark.parametrize("quant_type", ["int8wo"], ids=["int8wo"])
    def test_torchao_torch_compile(self, quant_type):
        self._test_torch_compile(TorchAoConfigMixin.TORCHAO_QUANT_TYPES[quant_type])

    @pytest.mark.parametrize("quant_type", ["int8wo"], ids=["int8wo"])
    def test_torchao_torch_compile_with_group_offload(self, quant_type):
        self._test_torch_compile_with_group_offload(TorchAoConfigMixin.TORCHAO_QUANT_TYPES[quant_type])


@is_gguf
@require_accelerate
@require_accelerator
@require_gguf_version_greater_or_equal("0.10.0")
class GGUFCompileTesterMixin(GGUFConfigMixin, QuantizationCompileTesterMixin):
    """
    Mixin class for testing torch.compile with GGUF quantized models.

    Expected from config mixin:
        - model_class: The model class to test

    Required properties (must be implemented by subclasses):
        - gguf_filename: URL or path to the GGUF file

    Expected methods from config mixin:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Pytest mark: gguf
        Use `pytest -m "not gguf"` to skip these tests
    """

    def test_gguf_torch_compile(self):
        self._test_torch_compile({"compute_dtype": torch.bfloat16})

    def test_gguf_torch_compile_with_group_offload(self):
        self._test_torch_compile_with_group_offload({"compute_dtype": torch.bfloat16})


@pytest.mark.skipif(not is_kernels_available(), reason="`kernels` is not available.")
@require_accelerate
@require_accelerator
class NunchakuLiteConfigMixin:
    """
    Base mixin providing Nunchaku Lite quantization config and model creation.

    Expected class attributes:
        - model_class: The model class to test
        - quantized_model_name_or_path: Hub repository ID or local path for the quantized model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained
    """

    config_dict = None

    def _create_quantized_model(self, config_kwargs=None, **extra_kwargs):
        kwargs = getattr(self, "pretrained_model_kwargs", {}).copy()
        if config_kwargs is not None:
            kwargs["quantization_config"] = NunchakuLiteQuantizationConfig(**config_kwargs)
        kwargs.update(extra_kwargs)
        return self.model_class.from_pretrained(self.quantized_model_name_or_path, **kwargs)

    def _verify_if_layer_quantized(self, name, module, config_kwargs):
        from diffusers.quantizers.nunchaku.utils import AWQW4A16Linear, SVDQW4A4Linear

        assert isinstance(module, (SVDQW4A4Linear, AWQW4A16Linear)), (
            f"Layer {name} is not a Nunchaku Lite layer, got {type(module)}"
        )


@pytest.mark.skipif(not is_kernels_available(), reason="`kernels` is not available.")
@require_accelerate
@require_accelerator
class NunchakuLiteTesterMixin(NunchakuLiteConfigMixin, QuantizationTesterMixin):
    """
    Mixin class for testing Nunchaku Lite quantization on models.

    Expected class attributes:
        - model_class: The model class to test
        - quantized_model_name_or_path: Hub repository ID or local path for the quantized model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass
    """

    def test_nunchaku_lite_quantization_inference(self):
        self._test_quantization_inference(self.config_dict)

    def _is_module_quantized(self, module):
        from diffusers.quantizers.nunchaku.utils import AWQW4A16Linear, SVDQW4A4Linear

        return isinstance(module, (SVDQW4A4Linear, AWQW4A16Linear))

    def _test_quantized_layers(self, config_kwargs):
        model = self._create_quantized_model(config_kwargs)

        num_quantized_layers = 0
        for name, module in model.named_modules():
            if self._is_module_quantized(module):
                self._verify_if_layer_quantized(name, module, config_kwargs)
                num_quantized_layers += 1

        expected_quantized_layers = sum(
            len(config_kwargs.get(section, {}).get("targets", [])) for section in ("svdq_w4a4", "awq_w4a16")
        )

        assert num_quantized_layers > 0, (
            f"No quantized layers found in model (expected {expected_quantized_layers} Nunchaku Lite layers)"
        )
        assert num_quantized_layers == expected_quantized_layers, (
            f"Quantized layer count mismatch: expected {expected_quantized_layers}, got {num_quantized_layers} "
            f"(configured Nunchaku Lite targets: {expected_quantized_layers})"
        )

    def test_nunchaku_lite_quantized_layers(self):
        self._test_quantized_layers(self.config_dict)


@pytest.mark.skipif(not is_kernels_available(), reason="`kernels` is not available.")
@require_accelerate
@require_accelerator
class NunchakuLiteCompileTesterMixin(NunchakuLiteConfigMixin, QuantizationCompileTesterMixin):
    """
    Mixin class for testing torch.compile with Nunchaku Lite quantized models.

    Expected class attributes:
        - model_class: The model class to test
        - quantized_model_name_or_path: Hub repository ID or local path for the quantized model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass
    """

    def test_nunchaku_lite_torch_compile(self):
        self._test_torch_compile(self.config_dict)

    def test_nunchaku_lite_torch_compile_with_group_offload(self):
        self._test_torch_compile_with_group_offload(self.config_dict)


@is_modelopt
@require_accelerator
@require_accelerate
@require_modelopt_version_greater_or_equal("0.33.1")
class ModelOptCompileTesterMixin(ModelOptConfigMixin, QuantizationCompileTesterMixin):
    """
    Mixin class for testing torch.compile with NVIDIA ModelOpt quantized models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Pytest mark: modelopt
        Use `pytest -m "not modelopt"` to skip these tests
    """

    @pytest.mark.parametrize("config_name", ["fp8"], ids=["fp8"])
    def test_modelopt_torch_compile(self, config_name):
        self._test_torch_compile(ModelOptConfigMixin.MODELOPT_CONFIGS[config_name])

    @pytest.mark.parametrize("config_name", ["fp8"], ids=["fp8"])
    def test_modelopt_torch_compile_with_group_offload(self, config_name):
        self._test_torch_compile_with_group_offload(ModelOptConfigMixin.MODELOPT_CONFIGS[config_name])


@is_sdnq
@require_sdnq
@require_accelerate
@require_accelerator
class SDNQCompileTesterMixin(SDNQConfigMixin, QuantizationCompileTesterMixin):
    """
    Mixin class for testing torch.compile with SDNQ quantized models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Pytest mark: sdnq
        Use `pytest -m "not sdnq"` to skip these tests
    """

    @pytest.mark.parametrize("config_name", ["int8"], ids=["int8"])
    def test_sdnq_torch_compile(self, config_name):
        self._test_torch_compile(SDNQConfigMixin.SDNQ_CONFIGS[config_name])

    @pytest.mark.parametrize("config_name", ["int8"], ids=["int8"])
    def test_sdnq_torch_compile_with_group_offload(self, config_name):
        self._test_torch_compile_with_group_offload(SDNQConfigMixin.SDNQ_CONFIGS[config_name])


@is_quantization
@is_autoround
@require_accelerator
@require_accelerate
@require_auto_round_version_greater_or_equal("0.13.0")
class AutoRoundConfigMixin:
    """
    Base mixin providing AutoRound quantization config and model creation.

    AutoRound is a weight-only quantization method (W4A16). It supports multiple inference

    When `backend="auto"`, AutoRound selects the best available backend automatically.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - quantized_model_name_or_path: Hub repository ID for the quantized model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained
    """

    config_dict = {"backend": "auto"}

    def _create_quantized_model(self, config_kwargs, **extra_kwargs):
        config = AutoRoundConfig(**config_kwargs)
        kwargs = getattr(self, "pretrained_model_kwargs", {}).copy()
        kwargs["quantization_config"] = config
        kwargs["torch_dtype"] = torch.bfloat16
        if "device_map" not in kwargs:
            kwargs["device_map"] = torch_device
        kwargs.update(extra_kwargs)
        return self.model_class.from_pretrained(self.quantized_model_name_or_path, **kwargs)

    def _verify_if_layer_quantized(self, name, module, config_kwargs):
        # AutoRound replaces linear layers with quantized linear layers
        assert isinstance(module, torch.nn.Linear), f"Layer {name} is not Linear, got {type(module)}"


@is_autoround
@require_accelerator
@require_accelerate
@require_auto_round_version_greater_or_equal("0.13.0")
class AutoRoundTesterMixin(AutoRoundConfigMixin, QuantizationTesterMixin):
    """
    Mixin class for testing AutoRound quantization on models.

    Expected class attributes:
        - model_class: The model class to test
        - pretrained_model_name_or_path: Hub repository ID for the pretrained model
        - quantized_model_name_or_path: Hub repository ID for the quantized model
        - pretrained_model_kwargs: (Optional) Dict of kwargs to pass to from_pretrained (e.g., {"subfolder": "transformer"})

    Expected methods to be implemented by subclasses:
        - get_dummy_inputs(): Returns dict of inputs to pass to the model forward pass

    Optional class attributes:
        - AUTOROUND_CONFIGS: Dict of config name -> AutoRoundConfig kwargs to test

    Pytest mark: autoround
        Use `pytest -m "not autoround"` to skip these tests
    """

    config_dict = {"backend": "auto"}

    def test_autoround_quantization_memory_footprint(self):
        expected = 1.5  # AutoRound is a W4A16 method, so we expect around 1.5x memory reduction
        self._test_quantization_memory_footprint(self.config_dict, expected_memory_reduction=expected)

    def test_autoround_quantization_inference(self):
        self._test_quantization_inference(self.config_dict)

    def test_autoround_device_map(self):
        """Test that device_map='auto' works correctly with quantization."""
        self._test_quantization_device_map(self.config_dict)


@is_autoround
@require_accelerator
@require_accelerate
@require_auto_round_version_greater_or_equal("0.13.0")
class AutoRoundCompileTesterMixin(AutoRoundConfigMixin, QuantizationCompileTesterMixin):
    """
    Mixin class for testing `torch.compile` with AutoRound-quantized models.

    This mixin provides tests that verify `torch.compile` works correctly with models
    quantized using AutoRound. Subclasses are expected to inherit from
    `AutoRoundConfigMixin` (which defines `config_dict`) and to provide the
    following class attributes: `model_class`, `pretrained_model_name_or_path`, and
    `quantized_model_name_or_path`.

    The mixin uses `config_dict` (defaults to {"backend": "auto"}) as the
    quantization configuration passed into `_create_quantized_model` when
    invoking the compile-related tests.

    Provided tests:
        - `test_autoround_torch_compile`: Ensures `torch.compile` runs and produces
          valid, non-NaN outputs for an AutoRound-quantized model.
        - `test_autoround_torch_compile_with_group_offload`: Ensures `torch.compile`
          works together with group offloading when supported by the quantized
          model implementation.
    """

    def test_autoround_torch_compile(self):
        self._test_torch_compile(self.config_dict, fullgraph=False, error_on_recompile=False)

    def test_autoround_torch_compile_with_group_offload(self):
        self._test_torch_compile_with_group_offload(self.config_dict)
