pytorch/torch/utils/data/_utils/fetch.py
Xuehai Pan 5b1cedacde [BE] [2/3] Rewrite super() calls in functorch and torch (#94588)
Rewrite Python built-in class `super()` calls. Only non-semantic changes should be applied.

- #94587
- #94588
- #94592

Also, methods with only a `super()` call are removed:

```diff
class MyModule(nn.Module):
-   def __init__(self):
-       super().__init__()
-
    def forward(self, ...):
        ...
```

Some cases that change the semantics should be kept unchanged. E.g.:

f152a79be9/caffe2/python/net_printer.py (L184-L190)

f152a79be9/test/test_jit_fuser_te.py (L2628-L2635)

Pull Request resolved: https://github.com/pytorch/pytorch/pull/94588
Approved by: https://github.com/ezyang, https://github.com/albanD
2023-02-10 21:16:33 +00:00

55 lines
1.9 KiB
Python

r""""Contains definitions of the methods used by the _BaseDataLoaderIter to fetch
data from an iterable-style or map-style dataset. This logic is shared in both
single- and multi-processing data loading.
"""
class _BaseDatasetFetcher:
def __init__(self, dataset, auto_collation, collate_fn, drop_last):
self.dataset = dataset
self.auto_collation = auto_collation
self.collate_fn = collate_fn
self.drop_last = drop_last
def fetch(self, possibly_batched_index):
raise NotImplementedError()
class _IterableDatasetFetcher(_BaseDatasetFetcher):
def __init__(self, dataset, auto_collation, collate_fn, drop_last):
super().__init__(dataset, auto_collation, collate_fn, drop_last)
self.dataset_iter = iter(dataset)
self.ended = False
def fetch(self, possibly_batched_index):
if self.ended:
raise StopIteration
if self.auto_collation:
data = []
for _ in possibly_batched_index:
try:
data.append(next(self.dataset_iter))
except StopIteration:
self.ended = True
break
if len(data) == 0 or (
self.drop_last and len(data) < len(possibly_batched_index)
):
raise StopIteration
else:
data = next(self.dataset_iter)
return self.collate_fn(data)
class _MapDatasetFetcher(_BaseDatasetFetcher):
def fetch(self, possibly_batched_index):
if self.auto_collation:
if hasattr(self.dataset, "__getitems__") and self.dataset.__getitems__:
data = self.dataset.__getitems__(possibly_batched_index)
else:
data = [self.dataset[idx] for idx in possibly_batched_index]
else:
data = self.dataset[possibly_batched_index]
return self.collate_fn(data)