CONTRIBUTING.md - third_party/libgit2 - Git at Google

 # Welcome to libgit2!

 We're making it easy to do interesting things with git, and we'd love to have
 your help.

 ## Licensing

 By contributing to libgit2, you agree to release your contribution under
 the terms of the license.  Except for the `examples` directory, all code
 is released under the [GPL v2 with linking exception](COPYING).

 The `examples` code is governed by the
 [CC0 Public Domain Dedication](examples/COPYING), so that you may copy
 from them into your own application.

 ## Discussion & Chat

 We hang out in the
 [`#libgit2`](http://webchat.freenode.net/?channels=#libgit2)) channel on
 irc.freenode.net.

 Also, feel free to open an
 [Issue](https://github.com/libgit2/libgit2/issues/new) to start a discussion
 about any concerns you have.  We like to use Issues for that so there is an
 easily accessible permanent record of the conversation.

 ## Libgit2 Versions

 The `master` branch is the main branch where development happens.
 Releases are tagged
 (e.g. [v0.21.0](https://github.com/libgit2/libgit2/releases/tag/v0.21.0) )
 and when a critical bug fix needs to be backported, it will be done on a
 `<tag>-maint` maintenance branch.

 ## Reporting Bugs

 First, know which version of libgit2 your problem is in and include it in
 your bug report.  This can either be a tag (e.g.
 [v0.17.0](https://github.com/libgit2/libgit2/releases/tag/v0.17.0)) or a
 commit SHA
 (e.g. [01be7863](https://github.com/libgit2/libgit2/commit/01be7863)).
 Using [`git describe`](http://git-scm.com/docs/git-describe) is a
 great way to tell us what version you're working with.

 If you're not running against the latest `master` branch version,
 please compile and test against that to avoid re-reporting an issue that's
 already been fixed.

 It's *incredibly* helpful to be able to reproduce the problem.  Please
 include a list of steps, a bit of code, and/or a zipped repository (if
 possible).  Note that some of the libgit2 developers are employees of
 GitHub, so if your repository is private, find us on IRC and we'll figure
 out a way to help you.

 ## Pull Requests

 Our work flow is a [typical GitHub
 flow](https://guides.github.com/introduction/flow/index.html), where
 contributors fork the [libgit2 repository](https://github.com/libgit2/libgit2),
 make their changes on branch, and submit a
 [Pull Request](https://help.github.com/articles/using-pull-requests)
 (a.k.a. "PR").  Pull requests should usually be targeted at the `master`
 branch.

 Life will be a lot easier for you (and us) if you follow this pattern
 (i.e. fork, named branch, submit PR).  If you use your fork's `master`
 branch directly, things can get messy.

 Please include a nice description of your changes when you submit your PR;
 if we have to read the whole diff to figure out why you're contributing
 in the first place, you're less likely to get feedback and have your change
 merged in.

 If you are starting to work on a particular area, feel free to submit a PR
 that highlights your work in progress (and note in the PR title that it's
 not ready to merge). These early PRs are welcome and will help in getting
 visibility for your fix, allow others to comment early on the changes and
 also let others know that you are currently working on something.

 Before wrapping up a PR, you should be sure to:

 * Write tests to cover any functional changes
 * Update documentation for any changed public APIs
 * Add to the [`CHANGELOG.md`](CHANGELOG.md) file describing any major changes

 ## Unit Tests

 We believe that our unit tests allow us to keep the quality of libgit2
 high: any new changes must not cause unit test failures, and new changes
 should include unit tests that cover the bug fixes or new features.
 For bug fixes, we prefer unit tests that illustrate the failure before
 the change, but pass with your changes.

 In addition to new tests, please ensure that your changes do not cause
 any other test failures.  Running the entire test suite is helpful
 before you submit a pull request.  When you build libgit2, the test
 suite will also be built.  You can run all tests by simply running
 the resultant `libgit2_clar` binary.  If you want to run a specific
 unit test, you can name it with the `-s` option.  For example:

     libgit2_clar -sstatus::worktree::long_filenames

 Or you can run an entire class of tests.  For example, to run all the
 worktree status tests:

     libgit2_clar -sstatus::worktree

 ## Porting Code From Other Open-Source Projects

 `libgit2` is licensed under the terms of the GPL v2 with a linking
 exception.  Any code brought in must be compatible with those terms.

 The most common case is porting code from core Git.  Git is a pure GPL
 project, which means that in order to port code to this project, we need the
 explicit permission of the author.  Check the
 [`git.git-authors`](https://github.com/libgit2/libgit2/blob/development/git.git-authors)
 file for authors who have already consented.

 Other licenses have other requirements; check the license of the library
 you're porting code *from* to see what you need to do.  As a general rule,
 MIT and BSD (3-clause) licenses are typically no problem.  Apache 2.0
 license typically doesn't work due to GPL incompatibility.

 If your pull request uses code from core Git, another project, or code
 from a forum / Stack Overflow, then *please* flag this in your PR and make
 sure you've given proper credit to the original author in the code
 snippet.

 ## Style Guide

 The public API of `libgit2` is [ANSI C](http://en.wikipedia.org/wiki/ANSI_C)
 (a.k.a. C89) compatible.  Internally, `libgit2` is written using a portable
 subset of C99 - in order to compile with GCC, Clang, MSVC, etc., we keep
 local variable declarations at the tops of blocks only and avoid `//` style
 comments.  Additionally, `libgit2` follows some extra conventions for
 function and type naming, code formatting, and testing.

 We like to keep the source code consistent and easy to read.  Maintaining
 this takes some discipline, but it's been more than worth it.  Take a look
 at the [conventions
 file](https://github.com/libgit2/libgit2/blob/development/CONVENTIONS.md).

 ## Starter Projects

 See our [projects
 list](https://github.com/libgit2/libgit2/blob/development/PROJECTS.md).
	# Welcome to libgit2!

	We're making it easy to do interesting things with git, and we'd love to have
	your help.

	## Licensing

	By contributing to libgit2, you agree to release your contribution under
	the terms of the license. Except for the `examples` directory, all code
	is released under the [GPL v2 with linking exception](COPYING).

	The `examples` code is governed by the
	[CC0 Public Domain Dedication](examples/COPYING), so that you may copy
	from them into your own application.

	## Discussion & Chat

	We hang out in the
	[`#libgit2`](http://webchat.freenode.net/?channels=#libgit2)) channel on
	irc.freenode.net.

	Also, feel free to open an
	[Issue](https://github.com/libgit2/libgit2/issues/new) to start a discussion
	about any concerns you have. We like to use Issues for that so there is an
	easily accessible permanent record of the conversation.

	## Libgit2 Versions

	The `master` branch is the main branch where development happens.
	Releases are tagged
	(e.g. [v0.21.0](https://github.com/libgit2/libgit2/releases/tag/v0.21.0) )
	and when a critical bug fix needs to be backported, it will be done on a
	`<tag>-maint` maintenance branch.

	## Reporting Bugs

	First, know which version of libgit2 your problem is in and include it in
	your bug report. This can either be a tag (e.g.
	[v0.17.0](https://github.com/libgit2/libgit2/releases/tag/v0.17.0)) or a
	commit SHA
	(e.g. [01be7863](https://github.com/libgit2/libgit2/commit/01be7863)).
	Using [`git describe`](http://git-scm.com/docs/git-describe) is a
	great way to tell us what version you're working with.

	If you're not running against the latest `master` branch version,
	please compile and test against that to avoid re-reporting an issue that's
	already been fixed.

	It's incredibly helpful to be able to reproduce the problem. Please
	include a list of steps, a bit of code, and/or a zipped repository (if
	possible). Note that some of the libgit2 developers are employees of
	GitHub, so if your repository is private, find us on IRC and we'll figure
	out a way to help you.

	## Pull Requests

	Our work flow is a [typical GitHub
	flow](https://guides.github.com/introduction/flow/index.html), where
	contributors fork the [libgit2 repository](https://github.com/libgit2/libgit2),
	make their changes on branch, and submit a
	[Pull Request](https://help.github.com/articles/using-pull-requests)
	(a.k.a. "PR"). Pull requests should usually be targeted at the `master`
	branch.

	Life will be a lot easier for you (and us) if you follow this pattern
	(i.e. fork, named branch, submit PR). If you use your fork's `master`
	branch directly, things can get messy.

	Please include a nice description of your changes when you submit your PR;
	if we have to read the whole diff to figure out why you're contributing
	in the first place, you're less likely to get feedback and have your change
	merged in.

	If you are starting to work on a particular area, feel free to submit a PR
	that highlights your work in progress (and note in the PR title that it's
	not ready to merge). These early PRs are welcome and will help in getting
	visibility for your fix, allow others to comment early on the changes and
	also let others know that you are currently working on something.

	Before wrapping up a PR, you should be sure to:

	* Write tests to cover any functional changes
	* Update documentation for any changed public APIs
	* Add to the [`CHANGELOG.md`](CHANGELOG.md) file describing any major changes

	## Unit Tests

	We believe that our unit tests allow us to keep the quality of libgit2
	high: any new changes must not cause unit test failures, and new changes
	should include unit tests that cover the bug fixes or new features.
	For bug fixes, we prefer unit tests that illustrate the failure before
	the change, but pass with your changes.

	In addition to new tests, please ensure that your changes do not cause
	any other test failures. Running the entire test suite is helpful
	before you submit a pull request. When you build libgit2, the test
	suite will also be built. You can run all tests by simply running
	the resultant `libgit2_clar` binary. If you want to run a specific
	unit test, you can name it with the `-s` option. For example:

	libgit2_clar -sstatus::worktree::long_filenames

	Or you can run an entire class of tests. For example, to run all the
	worktree status tests:

	libgit2_clar -sstatus::worktree

	## Porting Code From Other Open-Source Projects

	`libgit2` is licensed under the terms of the GPL v2 with a linking
	exception. Any code brought in must be compatible with those terms.

	The most common case is porting code from core Git. Git is a pure GPL
	project, which means that in order to port code to this project, we need the
	explicit permission of the author. Check the
	[`git.git-authors`](https://github.com/libgit2/libgit2/blob/development/git.git-authors)
	file for authors who have already consented.

	Other licenses have other requirements; check the license of the library
	you're porting code from to see what you need to do. As a general rule,
	MIT and BSD (3-clause) licenses are typically no problem. Apache 2.0
	license typically doesn't work due to GPL incompatibility.

	If your pull request uses code from core Git, another project, or code
	from a forum / Stack Overflow, then please flag this in your PR and make
	sure you've given proper credit to the original author in the code
	snippet.

	## Style Guide

	The public API of `libgit2` is [ANSI C](http://en.wikipedia.org/wiki/ANSI_C)
	(a.k.a. C89) compatible. Internally, `libgit2` is written using a portable
	subset of C99 - in order to compile with GCC, Clang, MSVC, etc., we keep
	local variable declarations at the tops of blocks only and avoid `//` style
	comments. Additionally, `libgit2` follows some extra conventions for
	function and type naming, code formatting, and testing.

	We like to keep the source code consistent and easy to read. Maintaining
	this takes some discipline, but it's been more than worth it. Take a look
	at the [conventions
	file](https://github.com/libgit2/libgit2/blob/development/CONVENTIONS.md).

	## Starter Projects

	See our [projects
	list](https://github.com/libgit2/libgit2/blob/development/PROJECTS.md).