Deprecate legacy constructor torch.Tensor()

[ysiraichi]

Fixes #47112

This pull request is the final step in the proposed plan for deprecating torch.Tensor() constructor. Specifically, it updates the docs and throws TORCH_WARN_ONCE if someone uses torch.Tensor().

[facebook-github-bot]

💊 CI failures summary and remediations

As of commit 4e49486 (more details on the Dr. CI page):

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• 2/5 failures introduced in this PR
• 3/5 broken upstream at merge base 7b939d9 from Mar 19 until Mar 23

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🕵️ 2 new failures recognized by patterns

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

pytorch_xla_linux_bionic_py3_6_clang9_build (1/2)

Step: "(Optional) Merge target branch" (full log | diagnosis details | 🔁 rerun)

Automatic merge failed; fix conflicts and then commit the result.

CONFLICT (add/add): Merge conflict in .circleci/regenerate.sh
Auto-merging .circleci/regenerate.sh
CONFLICT (add/add): Merge conflict in .circleci/docker/common/install_conda.sh
Auto-merging .circleci/docker/common/install_conda.sh
CONFLICT (add/add): Merge conflict in .circleci/docker/build.sh
Auto-merging .circleci/docker/build.sh
CONFLICT (add/add): Merge conflict in .circleci/config.yml
Auto-merging .circleci/config.yml
CONFLICT (add/add): Merge conflict in .circleci/cimodel/data/simple/docker_definitions.py
Auto-merging .circleci/cimodel/data/simple/docker_definitions.py
Automatic merge failed; fix conflicts and then commit the result.


Exited with code exit status 1

pytorch_linux_xenial_py3_6_gcc5_4_build (2/2)

Step: "(Optional) Merge target branch" (full log | diagnosis details | 🔁 rerun)

Automatic merge failed; fix conflicts and then commit the result.

CONFLICT (add/add): Merge conflict in .circleci/regenerate.sh
Auto-merging .circleci/regenerate.sh
CONFLICT (add/add): Merge conflict in .circleci/docker/common/install_conda.sh
Auto-merging .circleci/docker/common/install_conda.sh
CONFLICT (add/add): Merge conflict in .circleci/docker/build.sh
Auto-merging .circleci/docker/build.sh
CONFLICT (add/add): Merge conflict in .circleci/config.yml
Auto-merging .circleci/config.yml
CONFLICT (add/add): Merge conflict in .circleci/cimodel/data/simple/docker_definitions.py
Auto-merging .circleci/cimodel/data/simple/docker_definitions.py
Automatic merge failed; fix conflicts and then commit the result.


Exited with code exit status 1

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🚧 3 fixed upstream failures:

These were probably caused by upstream breakages that were already fixed.

Please rebase on the viable/strict branch (expand for instructions)

If your commit is older than viable/strict, run these commands:

git fetch https://github.com/pytorch/pytorch viable/strict
git rebase FETCH_HEAD

• pytorch_windows_vs2019_py36_cuda10.1_build from Mar 19 until Mar 23 (41b1ea2 - f3c0004)
  • 🔁 rerun
• pytorch_windows_vs2019_py36_cuda11.1_build from Mar 19 until Mar 23 (41b1ea2 - f3c0004)
  • 🔁 rerun
• pytorch_linux_xenial_cuda10_2_cudnn7_py3_gcc7_test1 from Mar 21 until Mar 22 (ab8e918 - 7b939d9)
  • 🔁 rerun

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[ysiraichi]

Here's a screenshot of a relevant part of the generated documentation (at tensors.html):

[facebook-github-bot]

@heitorschueroff has imported this pull request. If you are a Facebook employee, you can view this diff on Phabricator.

[facebook-github-bot]

@heitorschueroff has imported this pull request. If you are a Facebook employee, you can view this diff on Phabricator.

[facebook-github-bot]

@heitorschueroff merged this pull request in 4e5af53.

[heitorschueroff]

Reverting this change because of the warnings when people subclass Tensor. @ysiraichi apologies for not catching this problem before, we should continue discussion of how to correctly deprecate this in the issue you opened #55780