[WIP][DataLoader] Prototype of BatchIterableDataset

[ejguan]

Stack from ghstack:

• [WIP][DataLoader] Prototype of SamplerIterableDataset #49363 [WIP][DataLoader] Prototype of SamplerIterableDataset
• [WIP][DataLoader] Prototype of BatchIterableDataset #49186 [WIP][DataLoader] Prototype of BatchIterableDataset
• [WIP][DataLoader] CollateIterableDataset prototype #48933 [WIP][DataLoader] CollateIterableDataset prototype

For batch dataset, it should be followed by the collate dataset to stack the tensors or stack mapping...

Differential Revision: D25623636

[facebook-github-bot]

💊 CI failures summary and remediations

As of commit 26ecaa9 (more details on the Dr. CI page):

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• 2/2 failures possibly* introduced in this PR
  • 1/2 non-CircleCI failure(s)

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🕵️ 1 new failure recognized by patterns

The following CI failures do not appear to be due to upstream breakages:

pytorch_windows_vs2019_py36_cuda10.1_test1 (1/1)

Step: "Test" (full log | diagnosis details | 🔁 rerun)

[ FAILED ] CUDAPytorchToCaffe2.MutualResizes

  at_tensor[0][2].item().to<float>()
    Which is: 1
  345
[  FAILED  ] CUDAPytorchToCaffe2.MutualResizes (0 ms)
[----------] 3 tests from CUDAPytorchToCaffe2 (6 ms total)

[----------] Global test environment tear-down
[==========] 6 tests from 2 test cases ran. (2953 ms total)
[  PASSED  ] 5 tests.
[  FAILED  ] 1 test, listed below:
[  FAILED  ] CUDAPytorchToCaffe2.MutualResizes

 1 FAILED TEST
"cuda_tensor_interop_test" failed with exit code 1
+ cleanup
+ retcode=1
+ set +x


Exited with code exit status 1

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ci.pytorch.org: 1 failed

• Failed: pr/caffe2-pytorch-linux-bionic-rocm3.9-py3.6-test

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This comment has been revised 4 times.

[facebook-github-bot]

@ejguan merged this pull request in 554f79a.