[Fix] fix inferencer ut (open-mmlab#3117)

Author: xiexinch

tests/test_apis/test_inferencer.py

@@ -5,7 +5,6 @@
 import torch
 import torch.nn as nn
 from mmengine import ConfigDict
-from torch.utils.data import DataLoader, Dataset
 
 from mmseg.apis import MMSegInferencer
 from mmseg.models import EncoderDecoder
@@ -46,33 +45,8 @@ def __init__(self, **kwargs):
         super().__init__(**kwargs)
 
 
-class ExampleDataset(Dataset):
-
-    def __init__(self) -> None:
-        super().__init__()
-        self.pipeline = [
-            dict(type='LoadImageFromFile'),
-            dict(type='LoadAnnotations'),
-            dict(type='PackSegInputs')
-        ]
-
-    def __getitem__(self, idx):
-        return dict(img=torch.tensor([1]), img_metas=dict())
-
-    def __len__(self):
-        return 1
-
-
 def test_inferencer():
     register_all_modules()
-    test_dataset = ExampleDataset()
-    data_loader = DataLoader(
-        test_dataset,
-        batch_size=1,
-        sampler=None,
-        num_workers=0,
-        shuffle=False,
-    )
 
     visualizer = dict(
         type='SegLocalVisualizer',
@@ -87,7 +61,14 @@ def test_inferencer():
             decode_head=dict(type='InferExampleHead'),
             test_cfg=dict(mode='whole')),
         visualizer=visualizer,
-        test_dataloader=data_loader)
+        test_dataloader=dict(
+            dataset=dict(
+                type='ExampleDataset',
+                pipeline=[
+                    dict(type='LoadImageFromFile'),
+                    dict(type='LoadAnnotations'),
+                    dict(type='PackSegInputs')
+                ]), ))
     cfg = ConfigDict(cfg_dict)
     model = MODELS.build(cfg.model)