CONTRIBUTING.md - external/github.com/abseil/abseil-cpp - Git at Google


            
            # How to Contribute to Abseil


            We'd love to accept your patches and contributions to this project. There are

            
            just a few small guidelines you need to follow.


            NOTE: If you are new to GitHub, please start by reading [Pull Request

            
            howto](https://help.github.com/articles/about-pull-requests/)


            ## Contributor License Agreement


            Contributions to this project must be accompanied by a Contributor License

            
            Agreement. You (or your employer) retain the copyright to your contribution,

            
            this simply gives us permission to use and redistribute your contributions as

            
            part of the project. Head over to <https://cla.developers.google.com/> to see

            
            your current agreements on file or to sign a new one.


            You generally only need to submit a CLA once, so if you've already submitted one

            
            (even if it was for a different project), you probably don't need to do it

            
            again.


            ## Contribution Guidelines


            Potential contributors sometimes ask us if the Abseil project is the appropriate

            
            home for their utility library code or for specific functions implementing

            
            missing portions of the standard. Often, the answer to this question is "no".

            
            We’d like to articulate our thinking on this issue so that our choices can be

            
            understood by everyone and so that contributors can have a better intuition

            
            about whether Abseil might be interested in adopting a new library.


            ### Priorities


            Although our mission is to augment the C++ standard library, our goal is not to

            
            provide a full forward-compatible implementation of the latest standard. For us

            
            to consider a library for inclusion in Abseil, it is not enough that a library

            
            is useful. We generally choose to release a library when it meets at least one

            
            of the following criteria:


            *   **Widespread usage** - Using our internal codebase to help gauge usage, most

            
                of the libraries we've released have tens of thousands of users.

            
            *   **Anticipated widespread usage** - Pre-adoption of some standard-compliant

            
                APIs may not have broad adoption initially but can be expected to pick up

            
                usage when it replaces legacy APIs. `absl::from_chars`, for example,

            
                replaces existing code that converts strings to numbers and will therefore

            
                likely see usage growth.

            
            *   **High impact** - APIs that provide a key solution to a specific problem,

            
                such as `absl::FixedArray`, have higher impact than usage numbers may signal

            
                and are released because of their importance.

            
            *   **Direct support for a library that falls under one of the above** - When we

            
                want access to a smaller library as an implementation detail for a

            
                higher-priority library we plan to release, we may release it, as we did

            
                with portions of `absl/meta/type_traits.h`. One consequence of this is that

            
                the presence of a library in Abseil does not necessarily mean that other

            
                similar libraries would be a high priority.


            ### API Freeze Consequences


            Via the

            
            [Abseil Compatibility Guidelines](https://abseil.io/about/compatibility), we

            
            have promised a large degree of API stability. In particular, we will not make

            
            backward-incompatible changes to released APIs without also shipping a tool or

            
            process that can upgrade our users' code. We are not yet at the point of easily

            
            releasing such tools. Therefore, at this time, shipping a library establishes an

            
            API contract which is borderline unchangeable. (We can add new functionality,

            
            but we cannot easily change existing behavior.) This constraint forces us to

            
            very carefully review all APIs that we ship.


            ## Coding Style


            To keep the source consistent, readable, diffable and easy to merge, we use a

            
            fairly rigid coding style, as defined by the

            
            [google-styleguide](https://github.com/google/styleguide) project. All patches

            
            will be expected to conform to the style outlined

            
            [here](https://google.github.io/styleguide/cppguide.html).


            ## Guidelines for Pull Requests


            *   If you are a Googler, it is required that you send us a Piper CL instead of

            
                using the GitHub pull-request process. The code propagation process will

            
                deliver the change to GitHub.


            *   Create **small PRs** that are narrowly focused on **addressing a single

            
                concern**. We often receive PRs that are trying to fix several things at a

            
                time, but if only one fix is considered acceptable, nothing gets merged and

            
                both author's & review's time is wasted. Create more PRs to address

            
                different concerns and everyone will be happy.


            *   For speculative changes, consider opening an [Abseil

            
                issue](https://github.com/abseil/abseil-cpp/issues) and discussing it first.

            
                If you are suggesting a behavioral or API change, consider starting with an

            
                [Abseil proposal template](ABSEIL_ISSUE_TEMPLATE.md).


            *   Provide a good **PR description** as a record of **what** change is being

            
                made and **why** it was made. Link to a GitHub issue if it exists.


            *   Don't fix code style and formatting unless you are already changing that

            
                line to address an issue. Formatting of modified lines may be done using

            
               `git clang-format`. PRs with irrelevant changes won't be merged. If

            
                you do want to fix formatting or style, do that in a separate PR.


            *   Unless your PR is trivial, you should expect there will be reviewer comments

            
                that you'll need to address before merging. We expect you to be reasonably

            
                responsive to those comments, otherwise the PR will be closed after 2-3

            
                weeks of inactivity.


            *   Maintain **clean commit history** and use **meaningful commit messages**.

            
                PRs with messy commit history are difficult to review and won't be merged.

            
                Use `rebase -i upstream/master` to curate your commit history and/or to

            
                bring in latest changes from master (but avoid rebasing in the middle of a

            
                code review).


            *   Keep your PR up to date with upstream/master (if there are merge conflicts,

            
                we can't really merge your change).


            *   **All tests need to be passing** before your change can be merged. We

            
                recommend you **run tests locally** (see below)


            *   Exceptions to the rules can be made if there's a compelling reason for doing

            
                so. That is - the rules are here to serve us, not the other way around, and

            
                the rules need to be serving their intended purpose to be valuable.


            *   All submissions, including submissions by project members, require review.


            ## Running Tests


            If you have [Bazel](https://bazel.build/) installed, use `bazel test

            
            --test_tag_filters="-benchmark" ...` to run the unit tests.


            If you are running the Linux operating system and have

            
            [Docker](https://www.docker.com/) installed, you can also run the `linux_*.sh`

            
            scripts under the `ci/`(https://github.com/abseil/abseil-cpp/tree/master/ci)

            
            directory to test Abseil under a variety of conditions.


            ## Abseil Committers


            The current members of the Abseil engineering team are the only committers at

            
            present.


            ## Release Process


            Abseil lives at head, where latest-and-greatest code can be found.
	# How to Contribute to Abseil

	We'd love to accept your patches and contributions to this project. There are
	just a few small guidelines you need to follow.

	NOTE: If you are new to GitHub, please start by reading [Pull Request
	howto](https://help.github.com/articles/about-pull-requests/)

	## Contributor License Agreement

	Contributions to this project must be accompanied by a Contributor License
	Agreement. You (or your employer) retain the copyright to your contribution,
	this simply gives us permission to use and redistribute your contributions as
	part of the project. Head over to <https://cla.developers.google.com/> to see
	your current agreements on file or to sign a new one.

	You generally only need to submit a CLA once, so if you've already submitted one
	(even if it was for a different project), you probably don't need to do it
	again.

	## Contribution Guidelines

	Potential contributors sometimes ask us if the Abseil project is the appropriate
	home for their utility library code or for specific functions implementing
	missing portions of the standard. Often, the answer to this question is "no".
	We’d like to articulate our thinking on this issue so that our choices can be
	understood by everyone and so that contributors can have a better intuition
	about whether Abseil might be interested in adopting a new library.

	### Priorities

	Although our mission is to augment the C++ standard library, our goal is not to
	provide a full forward-compatible implementation of the latest standard. For us
	to consider a library for inclusion in Abseil, it is not enough that a library
	is useful. We generally choose to release a library when it meets at least one
	of the following criteria:

	* Widespread usage - Using our internal codebase to help gauge usage, most
	of the libraries we've released have tens of thousands of users.
	* Anticipated widespread usage - Pre-adoption of some standard-compliant
	APIs may not have broad adoption initially but can be expected to pick up
	usage when it replaces legacy APIs. `absl::from_chars`, for example,
	replaces existing code that converts strings to numbers and will therefore
	likely see usage growth.
	* High impact - APIs that provide a key solution to a specific problem,
	such as `absl::FixedArray`, have higher impact than usage numbers may signal
	and are released because of their importance.
	* Direct support for a library that falls under one of the above - When we
	want access to a smaller library as an implementation detail for a
	higher-priority library we plan to release, we may release it, as we did
	with portions of `absl/meta/type_traits.h`. One consequence of this is that
	the presence of a library in Abseil does not necessarily mean that other
	similar libraries would be a high priority.

	### API Freeze Consequences

	Via the
	[Abseil Compatibility Guidelines](https://abseil.io/about/compatibility), we
	have promised a large degree of API stability. In particular, we will not make
	backward-incompatible changes to released APIs without also shipping a tool or
	process that can upgrade our users' code. We are not yet at the point of easily
	releasing such tools. Therefore, at this time, shipping a library establishes an
	API contract which is borderline unchangeable. (We can add new functionality,
	but we cannot easily change existing behavior.) This constraint forces us to
	very carefully review all APIs that we ship.


	## Coding Style

	To keep the source consistent, readable, diffable and easy to merge, we use a
	fairly rigid coding style, as defined by the
	[google-styleguide](https://github.com/google/styleguide) project. All patches
	will be expected to conform to the style outlined
	[here](https://google.github.io/styleguide/cppguide.html).

	## Guidelines for Pull Requests

	* If you are a Googler, it is required that you send us a Piper CL instead of
	using the GitHub pull-request process. The code propagation process will
	deliver the change to GitHub.

	* Create small PRs that are narrowly focused on **addressing a single
	concern**. We often receive PRs that are trying to fix several things at a
	time, but if only one fix is considered acceptable, nothing gets merged and
	both author's & review's time is wasted. Create more PRs to address
	different concerns and everyone will be happy.

	* For speculative changes, consider opening an [Abseil
	issue](https://github.com/abseil/abseil-cpp/issues) and discussing it first.
	If you are suggesting a behavioral or API change, consider starting with an
	[Abseil proposal template](ABSEIL_ISSUE_TEMPLATE.md).

	* Provide a good PR description as a record of what change is being
	made and why it was made. Link to a GitHub issue if it exists.

	* Don't fix code style and formatting unless you are already changing that
	line to address an issue. Formatting of modified lines may be done using
	`git clang-format`. PRs with irrelevant changes won't be merged. If
	you do want to fix formatting or style, do that in a separate PR.

	* Unless your PR is trivial, you should expect there will be reviewer comments
	that you'll need to address before merging. We expect you to be reasonably
	responsive to those comments, otherwise the PR will be closed after 2-3
	weeks of inactivity.

	* Maintain clean commit history and use meaningful commit messages.
	PRs with messy commit history are difficult to review and won't be merged.
	Use `rebase -i upstream/master` to curate your commit history and/or to
	bring in latest changes from master (but avoid rebasing in the middle of a
	code review).

	* Keep your PR up to date with upstream/master (if there are merge conflicts,
	we can't really merge your change).

	* All tests need to be passing before your change can be merged. We
	recommend you run tests locally (see below)

	* Exceptions to the rules can be made if there's a compelling reason for doing
	so. That is - the rules are here to serve us, not the other way around, and
	the rules need to be serving their intended purpose to be valuable.

	* All submissions, including submissions by project members, require review.

	## Running Tests

	If you have [Bazel](https://bazel.build/) installed, use `bazel test
	--test_tag_filters="-benchmark" ...` to run the unit tests.

	If you are running the Linux operating system and have
	[Docker](https://www.docker.com/) installed, you can also run the `linux_*.sh`
	scripts under the `ci/`(https://github.com/abseil/abseil-cpp/tree/master/ci)
	directory to test Abseil under a variety of conditions.

	## Abseil Committers

	The current members of the Abseil engineering team are the only committers at
	present.

	## Release Process

	Abseil lives at head, where latest-and-greatest code can be found.