Added CONTRIBUTING.md (#1241)

Co-authored-by: moto <855818+mthrok@users.noreply.github.com>

CONTRIBUTING.md

+# Contributing to Torchaudio
+We want to make contributing to this project as easy and transparent as possible.
+
+## TL;DR
+
+Please let us know if you encounter a bug by filing an [issue](https://github.com/pytorch/audio/issues).
+
+We appreciate all contributions. If you are planning to contribute back
+bug-fixes, please do so without any further discussion.
+
+If you plan to contribute new features, utility functions or extensions to the
+core, please first open an issue and discuss the feature with us. Sending a PR
+without discussion might end up resulting in a rejected PR, because we might be
+taking the core in a different direction than you might be aware of.
+
+Fixing bugs and implementing new features are not the only way you can
+contribute. It also helps the project when you report problems you're facing,
+and when you give a :+1: on issues that others reported and that are relevant
+to you.
+
+You can also help by improving the documentation. This is no less important
+than improving the library itself! If you find a typo in the documentation,
+do not hesitate to submit a pull request.
+
+If you're not sure what you want to work on, you can pick an issue from the
+[list of open issues labelled as "help
+wanted"](https://github.com/pytorch/audio/issues?q=is%3Aopen+is%3Aissue+label%3A%22help+wanted%22).
+Comment on the issue that you want to work on it and send a PR with your fix
+(see below).
+
+## Development installation
+
+We recommend using a `conda` environment to contribute efficiently to
+torchaudio.
+
+### Install PyTorch Nightly 
+
+```bash
+conda install pytorch -c pytorch-nightly
+```
+
+### Install Torchaudio
+
+```bash
+pip install cmake ninja
+```
+
+```bash
+git clone https://github.com/pytorch/audio.git
+cd audio
+git submodule update --init --recursive
+BUILD_SOX=1 python setup.py develop
+# or, for OSX
+# BUILD_SOX=1 MACOSX_DEPLOYMENT_TARGET=10.9 CC=clang CXX=clang++ python setup.py develop
+# for C++ debugging, please use DEBUG=1
+# DEBUG=1 python setup.py install
+```
+
+Note: you don't need to use `BUILD_SOX=1` if you have `libsox-dev` installed
+already. If you built sox however, set the `PATH` variable so that the tests
+properly use the newly built `sox` binary:
+
+```bash
+export PATH="<path_to_torchaudio>/third_party/install/bin:${PATH}"
+```
+
+The following dependencies are also needed for testing:
+
+```bash
+pip install typing pytest scipy numpy parametrized
+```
+
+## Development Process
+
+If you plan to modify the code or documentation, please follow the steps below:
+
+1. Fork the repository and create your branch from `master`: `$ git checkout master && git checkout -b my_cool_feature`
+2. If you have modified the code (new feature or bug-fix), [please add tests](.test/torchaudio_unittest/).
+3. If you have changed APIs, [update the documentation](#Documentation).
+
+For more details about pull requests, 
+please read [GitHub's guides](https://docs.github.com/en/github/collaborating-with-issues-and-pull-requests/creating-a-pull-request). 
+
+If you would like to contribute a new model, please see [here](#New-model).
+
+If you would like to contribute a new dataset, please see [here](#New-dataset). 
+
+## Testing
+
+Please refer to our [testing guidelines](.test/torchaudio_unittest/) for more
+details.
+
+## Documentation
+
+Torchaudio uses [Google style](http://sphinxcontrib-napoleon.readthedocs.io/en/latest/example_google.html)
+for formatting docstrings. Length of line inside docstrings block must be limited to 120 characters.
+
+To build the docs, first install the requirements:
+
+```bash
+cd docs
+pip install -r requirements.txt
+```
+
+Then:
+
+```bash
+cd docs
+make html
+```
+
+The built docs should now be available in `docs/build/html`
+
+## License
+
+By contributing to Torchaudio, you agree that your contributions will be licensed
+under the LICENSE file in the root directory of this source tree.

README.md

@@ -232,15 +232,7 @@ Complex numbers are supported via tensors of dimension (..., 2), and torchaudio
 Contributing Guidelines
 -----------------------
 
-Please let us know if you encounter a bug by filing an [issue](https://github.com/pytorch/audio/issues).
-
-We appreciate all contributions. If you are planning to contribute back
-bug-fixes, please do so without any further discussion.
-
-If you plan to contribute new features, utility functions or extensions to the
-core, please first open an issue and discuss the feature with us. Sending a PR
-without discussion might end up resulting in a rejected PR, because we might be
-taking the core in a different direction than you might be aware of.
+Please refer to [CONTRIBUTING.md](./CONTRIBUTING.md)
 
 Disclaimer on Datasets
 ----------------------

test/torchaudio_unittest/README.md

@@ -2,9 +2,25 @@
 
 ## How to run test
 
-You can use `pytest` to run `torchaudio`'s test suites. See https://docs.pytest.org/ for the detail of how to use `pytest` command. The `parametrized` package is also needed; it can be installed via `pip` or with ` conda install -c conda-forge parameterized`.
+You can use `pytest` to run `torchaudio`'s test suites. See
+https://docs.pytest.org/ for the detail of how to use `pytest` command.
 
+For testing, the following packages are needed:
+
+```bash
+pip install typing pytest scipy numpy parametrized
+```
+
+Make sure to follow the installation instruction in the [contributing
+guide](../../CONTRIBUTING.md) first. For running `kaldi`-related tests:
+
+```bash
+export PATH="${PATH}:<path_to_kaldi>/src/featbin/"
 ```
+
+Some useful pytest commands:
+
+```bash
 # List up all the tests
 pytest test --collect-only
 # Run all the test suites
@@ -21,6 +37,11 @@ pytest test/torchaudio_unittest/sox_io_backend -k load  # only runs tests where
 
 **Note**
 We use PyTorch's test utilities instead of `pytest` frameworks when writing tests to avoid reinventing the wheel for Tensor comparison.
+Also, while we recommend using `pytest` for *running* the tests, we cannot
+make `pytest` a testing dependency of `torchaudio`. As a result, you should
+not import `pytest` or its submodules in the test files; Use the Python
+`unittest` builtin module instead, or the `parametrized` package to
+parametrize tests.
 
 ## Structure of tests
 
@@ -28,7 +49,7 @@ The following is an overview of the tests and related modules for `torchaudio`.
 
 ### Purpose specific test suites
 
-#### Numerical compatibility agains existing software
+#### Numerical compatibility against existing software
 - [Librosa compatibility test](./librosa_compatibility_test.py)
     Test suite for numerical compatibility against librosa.
 - [SoX compatibility test](./sox_compatibility_test.py)