diff --git a/tests/test_layers_utils.py b/tests/test_layers_utils.py
new file mode 100755
index 00000000..db4ed6eb
--- /dev/null
+++ b/tests/test_layers_utils.py
@@ -0,0 +1,738 @@
+# coding=utf-8
+# Copyright 2022 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 inspect
+import tempfile
+import unittest
+
+import numpy as np
+import torch
+
+from diffusers import (
+    BDDMPipeline,
+    DDIMPipeline,
+    DDIMScheduler,
+    DDPMPipeline,
+    DDPMScheduler,
+    GlidePipeline,
+    GlideSuperResUNetModel,
+    GlideTextToImageUNetModel,
+    GradTTSPipeline,
+    GradTTSScheduler,
+    LatentDiffusionPipeline,
+    PNDMPipeline,
+    PNDMScheduler,
+    UNetGradTTSModel,
+    UNetLDMModel,
+    UNetModel,
+)
+from diffusers.configuration_utils import ConfigMixin
+from diffusers.pipeline_utils import DiffusionPipeline
+from diffusers.pipelines.pipeline_bddm import DiffWave
+from diffusers.testing_utils import floats_tensor, slow, torch_device
+
+
+torch.backends.cuda.matmul.allow_tf32 = False
+
+
+class ConfigTester(unittest.TestCase):
+    def test_load_not_from_mixin(self):
+        with self.assertRaises(ValueError):
+            ConfigMixin.from_config("dummy_path")
+
+    def test_save_load(self):
+        class SampleObject(ConfigMixin):
+            config_name = "config.json"
+
+            def __init__(
+                self,
+                a=2,
+                b=5,
+                c=(2, 5),
+                d="for diffusion",
+                e=[1, 3],
+            ):
+                self.register_to_config(a=a, b=b, c=c, d=d, e=e)
+
+        obj = SampleObject()
+        config = obj.config
+
+        assert config["a"] == 2
+        assert config["b"] == 5
+        assert config["c"] == (2, 5)
+        assert config["d"] == "for diffusion"
+        assert config["e"] == [1, 3]
+
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            obj.save_config(tmpdirname)
+            new_obj = SampleObject.from_config(tmpdirname)
+            new_config = new_obj.config
+
+        # unfreeze configs
+        config = dict(config)
+        new_config = dict(new_config)
+
+        assert config.pop("c") == (2, 5)  # instantiated as tuple
+        assert new_config.pop("c") == [2, 5]  # saved & loaded as list because of json
+        assert config == new_config
+
+
+class ModelTesterMixin:
+    def test_from_pretrained_save_pretrained(self):
+        init_dict, inputs_dict = self.prepare_init_args_and_inputs_for_common()
+
+        model = self.model_class(**init_dict)
+        model.to(torch_device)
+        model.eval()
+
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            model.save_pretrained(tmpdirname)
+            new_model = self.model_class.from_pretrained(tmpdirname)
+            new_model.to(torch_device)
+
+        with torch.no_grad():
+            image = model(**inputs_dict)
+            new_image = new_model(**inputs_dict)
+
+        max_diff = (image - new_image).abs().sum().item()
+        self.assertLessEqual(max_diff, 1e-5, "Models give different forward passes")
+
+    def test_determinism(self):
+        init_dict, inputs_dict = self.prepare_init_args_and_inputs_for_common()
+        model = self.model_class(**init_dict)
+        model.to(torch_device)
+        model.eval()
+        with torch.no_grad():
+            first = model(**inputs_dict)
+            second = model(**inputs_dict)
+
+        out_1 = first.cpu().numpy()
+        out_2 = second.cpu().numpy()
+        out_1 = out_1[~np.isnan(out_1)]
+        out_2 = out_2[~np.isnan(out_2)]
+        max_diff = np.amax(np.abs(out_1 - out_2))
+        self.assertLessEqual(max_diff, 1e-5)
+
+    def test_output(self):
+        init_dict, inputs_dict = self.prepare_init_args_and_inputs_for_common()
+        model = self.model_class(**init_dict)
+        model.to(torch_device)
+        model.eval()
+
+        with torch.no_grad():
+            output = model(**inputs_dict)
+
+        self.assertIsNotNone(output)
+        expected_shape = inputs_dict["x"].shape
+        self.assertEqual(output.shape, expected_shape, "Input and output shapes do not match")
+
+    def test_forward_signature(self):
+        init_dict, _ = self.prepare_init_args_and_inputs_for_common()
+
+        model = self.model_class(**init_dict)
+        signature = inspect.signature(model.forward)
+        # signature.parameters is an OrderedDict => so arg_names order is deterministic
+        arg_names = [*signature.parameters.keys()]
+
+        expected_arg_names = ["x", "timesteps"]
+        self.assertListEqual(arg_names[:2], expected_arg_names)
+
+    def test_model_from_config(self):
+        init_dict, inputs_dict = self.prepare_init_args_and_inputs_for_common()
+
+        model = self.model_class(**init_dict)
+        model.to(torch_device)
+        model.eval()
+
+        # test if the model can be loaded from the config
+        # and has all the expected shape
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            model.save_config(tmpdirname)
+            new_model = self.model_class.from_config(tmpdirname)
+            new_model.to(torch_device)
+            new_model.eval()
+
+        # check if all paramters shape are the same
+        for param_name in model.state_dict().keys():
+            param_1 = model.state_dict()[param_name]
+            param_2 = new_model.state_dict()[param_name]
+            self.assertEqual(param_1.shape, param_2.shape)
+
+        with torch.no_grad():
+            output_1 = model(**inputs_dict)
+            output_2 = new_model(**inputs_dict)
+
+        self.assertEqual(output_1.shape, output_2.shape)
+
+    def test_training(self):
+        init_dict, inputs_dict = self.prepare_init_args_and_inputs_for_common()
+
+        model = self.model_class(**init_dict)
+        model.to(torch_device)
+        model.train()
+        output = model(**inputs_dict)
+        noise = torch.randn((inputs_dict["x"].shape[0],) + self.get_output_shape).to(torch_device)
+        loss = torch.nn.functional.mse_loss(output, noise)
+        loss.backward()
+
+
+class UnetModelTests(ModelTesterMixin, unittest.TestCase):
+    model_class = UNetModel
+
+    @property
+    def dummy_input(self):
+        batch_size = 4
+        num_channels = 3
+        sizes = (32, 32)
+
+        noise = floats_tensor((batch_size, num_channels) + sizes).to(torch_device)
+        time_step = torch.tensor([10]).to(torch_device)
+
+        return {"x": noise, "timesteps": time_step}
+
+    @property
+    def get_input_shape(self):
+        return (3, 32, 32)
+
+    @property
+    def get_output_shape(self):
+        return (3, 32, 32)
+
+    def prepare_init_args_and_inputs_for_common(self):
+        init_dict = {
+            "ch": 32,
+            "ch_mult": (1, 2),
+            "num_res_blocks": 2,
+            "attn_resolutions": (16,),
+            "resolution": 32,
+        }
+        inputs_dict = self.dummy_input
+        return init_dict, inputs_dict
+
+    def test_from_pretrained_hub(self):
+        model, loading_info = UNetModel.from_pretrained("fusing/ddpm_dummy", output_loading_info=True)
+        self.assertIsNotNone(model)
+        self.assertEqual(len(loading_info["missing_keys"]), 0)
+
+        model.to(torch_device)
+        image = model(**self.dummy_input)
+
+        assert image is not None, "Make sure output is not None"
+
+    def test_output_pretrained(self):
+        model = UNetModel.from_pretrained("fusing/ddpm_dummy")
+        model.eval()
+
+        torch.manual_seed(0)
+        if torch.cuda.is_available():
+            torch.cuda.manual_seed_all(0)
+
+        noise = torch.randn(1, model.config.in_channels, model.config.resolution, model.config.resolution)
+        time_step = torch.tensor([10])
+
+        with torch.no_grad():
+            output = model(noise, time_step)
+
+        output_slice = output[0, -1, -3:, -3:].flatten()
+        # fmt: off
+        expected_output_slice = torch.tensor([0.2891, -0.1899, 0.2595, -0.6214, 0.0968, -0.2622, 0.4688, 0.1311, 0.0053])
+        # fmt: on
+        self.assertTrue(torch.allclose(output_slice, expected_output_slice, atol=1e-3))
+
+
+class GlideSuperResUNetTests(ModelTesterMixin, unittest.TestCase):
+    model_class = GlideSuperResUNetModel
+
+    @property
+    def dummy_input(self):
+        batch_size = 4
+        num_channels = 6
+        sizes = (32, 32)
+        low_res_size = (4, 4)
+
+        noise = torch.randn((batch_size, num_channels // 2) + sizes).to(torch_device)
+        low_res = torch.randn((batch_size, 3) + low_res_size).to(torch_device)
+        time_step = torch.tensor([10] * noise.shape[0], device=torch_device)
+
+        return {"x": noise, "timesteps": time_step, "low_res": low_res}
+
+    @property
+    def get_input_shape(self):
+        return (3, 32, 32)
+
+    @property
+    def get_output_shape(self):
+        return (6, 32, 32)
+
+    def prepare_init_args_and_inputs_for_common(self):
+        init_dict = {
+            "attention_resolutions": (2,),
+            "channel_mult": (1, 2),
+            "in_channels": 6,
+            "out_channels": 6,
+            "model_channels": 32,
+            "num_head_channels": 8,
+            "num_heads_upsample": 1,
+            "num_res_blocks": 2,
+            "resblock_updown": True,
+            "resolution": 32,
+            "use_scale_shift_norm": True,
+        }
+        inputs_dict = self.dummy_input
+        return init_dict, inputs_dict
+
+    def test_output(self):
+        init_dict, inputs_dict = self.prepare_init_args_and_inputs_for_common()
+        model = self.model_class(**init_dict)
+        model.to(torch_device)
+        model.eval()
+
+        with torch.no_grad():
+            output = model(**inputs_dict)
+
+        output, _ = torch.split(output, 3, dim=1)
+
+        self.assertIsNotNone(output)
+        expected_shape = inputs_dict["x"].shape
+        self.assertEqual(output.shape, expected_shape, "Input and output shapes do not match")
+
+    def test_from_pretrained_hub(self):
+        model, loading_info = GlideSuperResUNetModel.from_pretrained(
+            "fusing/glide-super-res-dummy", output_loading_info=True
+        )
+        self.assertIsNotNone(model)
+        self.assertEqual(len(loading_info["missing_keys"]), 0)
+
+        model.to(torch_device)
+        image = model(**self.dummy_input)
+
+        assert image is not None, "Make sure output is not None"
+
+    def test_output_pretrained(self):
+        model = GlideSuperResUNetModel.from_pretrained("fusing/glide-super-res-dummy")
+
+        torch.manual_seed(0)
+        if torch.cuda.is_available():
+            torch.cuda.manual_seed_all(0)
+
+        noise = torch.randn(1, 3, 64, 64)
+        low_res = torch.randn(1, 3, 4, 4)
+        time_step = torch.tensor([42] * noise.shape[0])
+
+        with torch.no_grad():
+            output = model(noise, time_step, low_res)
+
+        output, _ = torch.split(output, 3, dim=1)
+        output_slice = output[0, -1, -3:, -3:].flatten()
+        # fmt: off
+        expected_output_slice = torch.tensor([-22.8782, -23.2652, -15.3966, -22.8034, -23.3159, -15.5640, -15.3970, -15.4614, - 10.4370])
+        # fmt: on
+        self.assertTrue(torch.allclose(output_slice, expected_output_slice, atol=1e-3))
+
+
+class GlideTextToImageUNetModelTests(ModelTesterMixin, unittest.TestCase):
+    model_class = GlideTextToImageUNetModel
+
+    @property
+    def dummy_input(self):
+        batch_size = 4
+        num_channels = 3
+        sizes = (32, 32)
+        transformer_dim = 32
+        seq_len = 16
+
+        noise = torch.randn((batch_size, num_channels) + sizes).to(torch_device)
+        emb = torch.randn((batch_size, seq_len, transformer_dim)).to(torch_device)
+        time_step = torch.tensor([10] * noise.shape[0], device=torch_device)
+
+        return {"x": noise, "timesteps": time_step, "transformer_out": emb}
+
+    @property
+    def get_input_shape(self):
+        return (3, 32, 32)
+
+    @property
+    def get_output_shape(self):
+        return (6, 32, 32)
+
+    def prepare_init_args_and_inputs_for_common(self):
+        init_dict = {
+            "attention_resolutions": (2,),
+            "channel_mult": (1, 2),
+            "in_channels": 3,
+            "out_channels": 6,
+            "model_channels": 32,
+            "num_head_channels": 8,
+            "num_heads_upsample": 1,
+            "num_res_blocks": 2,
+            "resblock_updown": True,
+            "resolution": 32,
+            "use_scale_shift_norm": True,
+            "transformer_dim": 32,
+        }
+        inputs_dict = self.dummy_input
+        return init_dict, inputs_dict
+
+    def test_output(self):
+        init_dict, inputs_dict = self.prepare_init_args_and_inputs_for_common()
+        model = self.model_class(**init_dict)
+        model.to(torch_device)
+        model.eval()
+
+        with torch.no_grad():
+            output = model(**inputs_dict)
+
+        output, _ = torch.split(output, 3, dim=1)
+
+        self.assertIsNotNone(output)
+        expected_shape = inputs_dict["x"].shape
+        self.assertEqual(output.shape, expected_shape, "Input and output shapes do not match")
+
+    def test_from_pretrained_hub(self):
+        model, loading_info = GlideTextToImageUNetModel.from_pretrained(
+            "fusing/unet-glide-text2im-dummy", output_loading_info=True
+        )
+        self.assertIsNotNone(model)
+        self.assertEqual(len(loading_info["missing_keys"]), 0)
+
+        model.to(torch_device)
+        image = model(**self.dummy_input)
+
+        assert image is not None, "Make sure output is not None"
+
+    def test_output_pretrained(self):
+        model = GlideTextToImageUNetModel.from_pretrained("fusing/unet-glide-text2im-dummy")
+
+        torch.manual_seed(0)
+        if torch.cuda.is_available():
+            torch.cuda.manual_seed_all(0)
+
+        noise = torch.randn((1, model.config.in_channels, model.config.resolution, model.config.resolution)).to(
+            torch_device
+        )
+        emb = torch.randn((1, 16, model.config.transformer_dim)).to(torch_device)
+        time_step = torch.tensor([10] * noise.shape[0], device=torch_device)
+
+        with torch.no_grad():
+            output = model(noise, time_step, emb)
+
+        output, _ = torch.split(output, 3, dim=1)
+        output_slice = output[0, -1, -3:, -3:].flatten()
+        # fmt: off
+        expected_output_slice = torch.tensor([2.7766, -10.3558, -14.9149, -0.9376, -14.9175, -17.7679, -5.5565, -12.9521, -12.9845])
+        # fmt: on
+        self.assertTrue(torch.allclose(output_slice, expected_output_slice, atol=1e-3))
+
+
+class UNetLDMModelTests(ModelTesterMixin, unittest.TestCase):
+    model_class = UNetLDMModel
+
+    @property
+    def dummy_input(self):
+        batch_size = 4
+        num_channels = 4
+        sizes = (32, 32)
+
+        noise = floats_tensor((batch_size, num_channels) + sizes).to(torch_device)
+        time_step = torch.tensor([10]).to(torch_device)
+
+        return {"x": noise, "timesteps": time_step}
+
+    @property
+    def get_input_shape(self):
+        return (4, 32, 32)
+
+    @property
+    def get_output_shape(self):
+        return (4, 32, 32)
+
+    def prepare_init_args_and_inputs_for_common(self):
+        init_dict = {
+            "image_size": 32,
+            "in_channels": 4,
+            "out_channels": 4,
+            "model_channels": 32,
+            "num_res_blocks": 2,
+            "attention_resolutions": (16,),
+            "channel_mult": (1, 2),
+            "num_heads": 2,
+            "conv_resample": True,
+        }
+        inputs_dict = self.dummy_input
+        return init_dict, inputs_dict
+
+    def test_from_pretrained_hub(self):
+        model, loading_info = UNetLDMModel.from_pretrained("fusing/unet-ldm-dummy", output_loading_info=True)
+        self.assertIsNotNone(model)
+        self.assertEqual(len(loading_info["missing_keys"]), 0)
+
+        model.to(torch_device)
+        image = model(**self.dummy_input)
+
+        assert image is not None, "Make sure output is not None"
+
+    def test_output_pretrained(self):
+        model = UNetLDMModel.from_pretrained("fusing/unet-ldm-dummy")
+        model.eval()
+
+        torch.manual_seed(0)
+        if torch.cuda.is_available():
+            torch.cuda.manual_seed_all(0)
+
+        noise = torch.randn(1, model.config.in_channels, model.config.image_size, model.config.image_size)
+        time_step = torch.tensor([10] * noise.shape[0])
+
+        with torch.no_grad():
+            output = model(noise, time_step)
+
+        output_slice = output[0, -1, -3:, -3:].flatten()
+        # fmt: off
+        expected_output_slice = torch.tensor([-13.3258, -20.1100, -15.9873, -17.6617, -23.0596, -17.9419, -13.3675, -16.1889, -12.3800])
+        # fmt: on
+
+        self.assertTrue(torch.allclose(output_slice, expected_output_slice, atol=1e-3))
+
+
+class UNetGradTTSModelTests(ModelTesterMixin, unittest.TestCase):
+    model_class = UNetGradTTSModel
+
+    @property
+    def dummy_input(self):
+        batch_size = 4
+        num_features = 32
+        seq_len = 16
+
+        noise = floats_tensor((batch_size, num_features, seq_len)).to(torch_device)
+        condition = floats_tensor((batch_size, num_features, seq_len)).to(torch_device)
+        mask = floats_tensor((batch_size, 1, seq_len)).to(torch_device)
+        time_step = torch.tensor([10] * batch_size).to(torch_device)
+
+        return {"x": noise, "timesteps": time_step, "mu": condition, "mask": mask}
+
+    @property
+    def get_input_shape(self):
+        return (4, 32, 16)
+
+    @property
+    def get_output_shape(self):
+        return (4, 32, 16)
+
+    def prepare_init_args_and_inputs_for_common(self):
+        init_dict = {
+            "dim": 64,
+            "groups": 4,
+            "dim_mults": (1, 2),
+            "n_feats": 32,
+            "pe_scale": 1000,
+            "n_spks": 1,
+        }
+        inputs_dict = self.dummy_input
+        return init_dict, inputs_dict
+
+    def test_from_pretrained_hub(self):
+        model, loading_info = UNetGradTTSModel.from_pretrained("fusing/unet-grad-tts-dummy", output_loading_info=True)
+        self.assertIsNotNone(model)
+        self.assertEqual(len(loading_info["missing_keys"]), 0)
+
+        model.to(torch_device)
+        image = model(**self.dummy_input)
+
+        assert image is not None, "Make sure output is not None"
+
+    def test_output_pretrained(self):
+        model = UNetGradTTSModel.from_pretrained("fusing/unet-grad-tts-dummy")
+        model.eval()
+
+        torch.manual_seed(0)
+        if torch.cuda.is_available():
+            torch.cuda.manual_seed_all(0)
+
+        num_features = model.config.n_feats
+        seq_len = 16
+        noise = torch.randn((1, num_features, seq_len))
+        condition = torch.randn((1, num_features, seq_len))
+        mask = torch.randn((1, 1, seq_len))
+        time_step = torch.tensor([10])
+
+        with torch.no_grad():
+            output = model(noise, time_step, condition, mask)
+
+        output_slice = output[0, -3:, -3:].flatten()
+        # fmt: off
+        expected_output_slice = torch.tensor([-0.0690, -0.0531, 0.0633, -0.0660, -0.0541, 0.0650, -0.0656, -0.0555, 0.0617])
+        # fmt: on
+
+        self.assertTrue(torch.allclose(output_slice, expected_output_slice, atol=1e-3))
+
+
+class PipelineTesterMixin(unittest.TestCase):
+    def test_from_pretrained_save_pretrained(self):
+        # 1. Load models
+        model = UNetModel(ch=32, ch_mult=(1, 2), num_res_blocks=2, attn_resolutions=(16,), resolution=32)
+        schedular = DDPMScheduler(timesteps=10)
+
+        ddpm = DDPMPipeline(model, schedular)
+
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            ddpm.save_pretrained(tmpdirname)
+            new_ddpm = DDPMPipeline.from_pretrained(tmpdirname)
+
+        generator = torch.manual_seed(0)
+
+        image = ddpm(generator=generator)
+        generator = generator.manual_seed(0)
+        new_image = new_ddpm(generator=generator)
+
+        assert (image - new_image).abs().sum() < 1e-5, "Models don't give the same forward pass"
+
+    @slow
+    def test_from_pretrained_hub(self):
+        model_path = "fusing/ddpm-cifar10"
+
+        ddpm = DDPMPipeline.from_pretrained(model_path)
+        ddpm_from_hub = DiffusionPipeline.from_pretrained(model_path)
+
+        ddpm.noise_scheduler.num_timesteps = 10
+        ddpm_from_hub.noise_scheduler.num_timesteps = 10
+
+        generator = torch.manual_seed(0)
+
+        image = ddpm(generator=generator)
+        generator = generator.manual_seed(0)
+        new_image = ddpm_from_hub(generator=generator)
+
+        assert (image - new_image).abs().sum() < 1e-5, "Models don't give the same forward pass"
+
+    @slow
+    def test_ddpm_cifar10(self):
+        generator = torch.manual_seed(0)
+        model_id = "fusing/ddpm-cifar10"
+
+        unet = UNetModel.from_pretrained(model_id)
+        noise_scheduler = DDPMScheduler.from_config(model_id)
+        noise_scheduler = noise_scheduler.set_format("pt")
+
+        ddpm = DDPMPipeline(unet=unet, noise_scheduler=noise_scheduler)
+        image = ddpm(generator=generator)
+
+        image_slice = image[0, -1, -3:, -3:].cpu()
+
+        assert image.shape == (1, 3, 32, 32)
+        expected_slice = torch.tensor([0.2250, 0.3375, 0.2360, 0.0930, 0.3440, 0.3156, 0.1937, 0.3585, 0.1761])
+        assert (image_slice.flatten() - expected_slice).abs().max() < 1e-2
+
+    @slow
+    def test_ddim_cifar10(self):
+        generator = torch.manual_seed(0)
+        model_id = "fusing/ddpm-cifar10"
+
+        unet = UNetModel.from_pretrained(model_id)
+        noise_scheduler = DDIMScheduler(tensor_format="pt")
+
+        ddim = DDIMPipeline(unet=unet, noise_scheduler=noise_scheduler)
+        image = ddim(generator=generator, eta=0.0)
+
+        image_slice = image[0, -1, -3:, -3:].cpu()
+
+        assert image.shape == (1, 3, 32, 32)
+        expected_slice = torch.tensor(
+            [-0.7383, -0.7385, -0.7298, -0.7364, -0.7414, -0.7239, -0.6737, -0.6813, -0.7068]
+        )
+        assert (image_slice.flatten() - expected_slice).abs().max() < 1e-2
+
+    @slow
+    def test_pndm_cifar10(self):
+        generator = torch.manual_seed(0)
+        model_id = "fusing/ddpm-cifar10"
+
+        unet = UNetModel.from_pretrained(model_id)
+        noise_scheduler = PNDMScheduler(tensor_format="pt")
+
+        pndm = PNDMPipeline(unet=unet, noise_scheduler=noise_scheduler)
+        image = pndm(generator=generator)
+
+        image_slice = image[0, -1, -3:, -3:].cpu()
+
+        assert image.shape == (1, 3, 32, 32)
+        expected_slice = torch.tensor(
+            [-0.7888, -0.7870, -0.7759, -0.7823, -0.8014, -0.7608, -0.6818, -0.7130, -0.7471]
+        )
+        assert (image_slice.flatten() - expected_slice).abs().max() < 1e-2
+
+    @slow
+    def test_ldm_text2img(self):
+        model_id = "fusing/latent-diffusion-text2im-large"
+        ldm = LatentDiffusionPipeline.from_pretrained(model_id)
+
+        prompt = "A painting of a squirrel eating a burger"
+        generator = torch.manual_seed(0)
+        image = ldm([prompt], generator=generator, num_inference_steps=20)
+
+        image_slice = image[0, -1, -3:, -3:].cpu()
+
+        assert image.shape == (1, 3, 256, 256)
+        expected_slice = torch.tensor([0.7295, 0.7358, 0.7256, 0.7435, 0.7095, 0.6884, 0.7325, 0.6921, 0.6458])
+        assert (image_slice.flatten() - expected_slice).abs().max() < 1e-2
+
+    @slow
+    def test_glide_text2img(self):
+        model_id = "fusing/glide-base"
+        glide = GlidePipeline.from_pretrained(model_id)
+
+        prompt = "a pencil sketch of a corgi"
+        generator = torch.manual_seed(0)
+        image = glide(prompt, generator=generator, num_inference_steps_upscale=20)
+
+        image_slice = image[0, :3, :3, -1].cpu()
+
+        assert image.shape == (1, 256, 256, 3)
+        expected_slice = torch.tensor([0.7119, 0.7073, 0.6460, 0.7780, 0.7423, 0.6926, 0.7378, 0.7189, 0.7784])
+        assert (image_slice.flatten() - expected_slice).abs().max() < 1e-2
+
+    @slow
+    def test_grad_tts(self):
+        model_id = "fusing/grad-tts-libri-tts"
+        grad_tts = GradTTSPipeline.from_pretrained(model_id)
+        noise_scheduler = GradTTSScheduler()
+        grad_tts.noise_scheduler = noise_scheduler
+
+        text = "Hello world, I missed you so much."
+        generator = torch.manual_seed(0)
+
+        # generate mel spectograms using text
+        mel_spec = grad_tts(text, generator=generator)
+
+        assert mel_spec.shape == (1, 80, 143)
+        expected_slice = torch.tensor(
+            [-6.7584, -6.8347, -6.3293, -6.6437, -6.7233, -6.4684, -6.1187, -6.3172, -6.6890]
+        )
+        assert (mel_spec[0, :3, :3].cpu().flatten() - expected_slice).abs().max() < 1e-2
+
+    def test_module_from_pipeline(self):
+        model = DiffWave(num_res_layers=4)
+        noise_scheduler = DDPMScheduler(timesteps=12)
+
+        bddm = BDDMPipeline(model, noise_scheduler)
+
+        # check if the library name for the diffwave moduel is set to pipeline module
+        self.assertTrue(bddm.config["diffwave"][0] == "pipeline_bddm")
+
+        # check if we can save and load the pipeline
+        with tempfile.TemporaryDirectory() as tmpdirname:
+            bddm.save_pretrained(tmpdirname)
+            _ = BDDMPipeline.from_pretrained(tmpdirname)
+            # check if the same works using the DifusionPipeline class
+            _ = DiffusionPipeline.from_pretrained(tmpdirname)