Enable PyTorch 1.7 in conda CI

[ydcjeff]

What does this PR do?

Fixes #3531

Python property support for PyTorch JIT PR (v1.7): pytorch/pytorch#42390

Thanks to ptrblck

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[codecov]

Codecov Report

Merging #3541 into master will increase coverage by 1%.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #3541   +/-   ##
======================================
+ Coverage      90%     91%   +1%     
======================================
  Files         110     110           
  Lines        8129    8069   -60     
======================================
- Hits         7331    7323    -8     
+ Misses        798     746   -52     

[Borda]

lets first finis the tests fixing here and later follow up in #3543

[Borda]

it seems that most of the TorchScript are failing

FAILED tests/models/test_cpu.py::test_lbfgs_cpu_model - AssertionError: This ...
FAILED tests/models/test_torchscript.py::test_torchscript_input_output[EvalModelTemplate]
FAILED tests/models/test_torchscript.py::test_torchscript_input_output[ParityModuleRNN]
FAILED tests/models/test_torchscript.py::test_torchscript_input_output[BasicGAN]
FAILED tests/models/test_torchscript.py::test_torchscript_retain_training_state
FAILED tests/models/test_torchscript.py::test_torchscript_properties[EvalModelTemplate]
FAILED tests/models/test_torchscript.py::test_torchscript_properties[ParityModuleRNN]
FAILED tests/models/test_torchscript.py::test_torchscript_properties[BasicGAN]
FAILED tests/models/test_torchscript.py::test_torchscript_save_load[EvalModelTemplate]
FAILED tests/models/test_torchscript.py::test_torchscript_save_load[ParityModuleRNN]
FAILED tests/models/test_torchscript.py::test_torchscript_save_load[BasicGAN]

and it seems there is issue with DataModule:

>       concrete_type._create_methods_and_properties(property_defs, property_rcbs, method_defs, method_rcbs, method_defaults)
E       RuntimeError: Can't redefine method: __datamodule_getter on class: __torch__.tests.base.models.ParityModuleRNN

@nateraw mind have look, pls

[ydcjeff]

Seems like there is something update to the JIT.

• Using torch 1.7.0.dev20200915, test failed https://github.com/PyTorchLightning/pytorch-lightning/runs/1139697173
• Using torch 1.7.0.dev20200914, test passed https://github.com/PyTorchLightning/pytorch-lightning/runs/1139697179

But not sure the cause is from Lightning or PyTorch.

[Borda]

Maybe move this testing to some alternative ci/badge? @williamFalcon

[ydcjeff]

to_torchscript now works with PyTorch 1.7 nightly. This is done via __ignored_properties__, from https://github.com/pytorch/pytorch/pull/42390/files#diff-ff4f8670281cd1eb4e09329cc1dcb43b

So far I have ignored all the properties in LightningModule (some are from DeviceDtypeMixin) that would cause torchscript tests failing.

Question:

• What properties should we ignore and not ignore? (since I am not sure), but we are only converting LightningModule to TorchScript, right?

TorchScript doesn't support Union type.

There is a related PR #3295 doing similarly for 1.7 JIT support.

Finally for these kind of breaking changes, would it be better to have separate ci/badge?

@williamFalcon @Borda @nateraw @awaelchli

[Borda]

LGTM

[SkafteNicki]

LGTM

[mergify]

This pull request is now in conflict... :(