Taichi: Revamp dependencies and build system

[kigawas]

• Separate dependecies and dev-dependencies (like pytest), pyproject.toml could be an option

• Make it easier to build and deploy

Several links which may be helpful

• https://github.com/dephell/dephell
• https://github.com/python-poetry/poetry
• https://github.com/apache/incubator-mxnet/blob/master/python/setup.py
• https://github.com/scikit-learn/scikit-learn/blob/master/setup.py

[rexwangcc]

Thanks for the suggestion! Unpacking the links provided above, I think this issue proposed discussions around 2 points:

1. Separate dev/test-deps from the main deps
2. Switch to use other dependency managers such as poetry

While I strongly agree with 1. and I believe it's something feasible to do in very short term, 2. requires more changes to the whole packaging, CI and releasing process, since poetry specifically does not yet provide a native support (it seems dephell supports it) for generating setup.py which might still be useful for some of the CI/dev tools at the moment.

[liaopeiyuan]

If I'm getting it right, is it true that currently we only support MacOS build on Travis CI? Could be a bit more helpful to add Linux/Windows builds for more sanity checks, and maybe older version builds to address confusions like #1099.

Additionally, are we considering something related to code coverage?

[rexwangcc]

We do have Linux build and Windows build, but we don't have any tests cases for the CLI which is a tech debt.

1085 is trying to refactor the CLI and add test cases to avoid something like #1099 to happen in the future. But until it's out, I expect we'd receive more protability issues as more users are trying to ramp up with Taichi from different platforms 😅 .

[archibate]

FYI currently we use GitHub Actions for Linux build (#1023), AppVeyor for Windows build. We're considering to merge Windows & Mac OS X build into GitHub Actions, and purchase a self-hosted GitHub Actions runner at some point.

Additionally, are we considering something related to code coverage?

Yes, see #677, codecov.