1 # Contributing to libjxl
3 ## Contributing with bug reports
5 For security-related issues please see [SECURITY.md](SECURITY.md).
7 We welcome suggestions, feature requests and bug reports. Before opening a new
8 issue please take a look if there is already an existing one in the following
11 * https://github.com/libjxl/libjxl/issues
13 ## Contributing with patches and Pull Requests
15 We'd love to accept your contributions to the JPEG XL Project. Please read
16 through this section before sending a Pull Request.
18 ### Contributor License Agreements
20 Our project is open source under the terms outlined in the [LICENSE](LICENSE)
21 and [PATENTS](PATENTS) files. Before we can accept your contributions, even for
22 small changes, there are just a few small guidelines you need to follow:
24 Please fill out either the individual or corporate Contributor License Agreement
25 (CLA) with Google. JPEG XL Project is an an effort by multiple individuals and
26 companies, including the initial contributors Cloudinary and Google, but Google
27 is the legal entity in charge of receiving these CLA and relicensing this
30 * If you are an individual writing original source code and you're sure you
31 own the intellectual property, then you'll need to sign an [individual
32 CLA](https://code.google.com/legal/individual-cla-v1.0.html).
34 * If you work for a company that wants to allow you to contribute your work,
35 then you'll need to sign a [corporate
36 CLA](https://code.google.com/legal/corporate-cla-v1.0.html).
38 Follow either of the two links above to access the appropriate CLA and
39 instructions for how to sign and return it. Once we receive it, we'll be able
40 to accept your pull requests.
42 ***NOTE***: Only original source code from you and other people that have signed
43 the CLA can be accepted into the main repository.
47 Contributions are licensed under the project's [LICENSE](LICENSE). Each new
48 file must include the following header when possible, with comment style adapted
49 to the language as needed:
52 // Copyright (c) the JPEG XL Project Authors. All rights reserved.
54 // Use of this source code is governed by a BSD-style
55 // license that can be found in the LICENSE file.
60 All submissions, including submissions by project members, require review. We
61 use GitHub pull requests for this purpose. Consult
62 [GitHub Help](https://help.github.com/articles/about-pull-requests/) for more
63 information on using pull requests.
65 ### Contribution philosophy
67 * Prefer small changes, even if they don't implement a complete feature. Small
68 changes are easier to review and can be submitted faster. Think about what's
69 the smallest unit you can send that makes sense to review and submit in
70 isolation. For example, new modules that are not yet used by the tools but
71 have their own unittests are ok. If you have unrelated changes that
72 you discovered while working on something else, please send them in a
73 different Pull Request. If your are refactoring code and changing
74 functionality try to send the refactor first without any change in
75 functionality. Reviewers may ask you to split a Pull Request and it is
76 easier to create a smaller change from the beginning.
78 * Describe your commits. Add a meaningful description to your commit message,
79 explain what you are changing if it is not trivially obvious, but more
80 importantly explain *why* you are making those changes. For example "Fix
81 build" is not a good commit message, describe what build and if it makes sense
82 why is this fixing it or why was it failing without this. It is very likely
83 that people far in the future without any context you have right now will be
84 looking at your commit trying to figure out why was the change introduced. If
85 related to an issue in this or another repository include a link to it.
87 * Code Style: We follow the [Google C++ Coding
88 Style](https://google.github.io/styleguide/cppguide.html). A
89 [clang-format](https://clang.llvm.org/docs/ClangFormat.html) configuration
90 file is available to automatically format your code, you can invoke it with
91 the `./ci.sh lint` helper tool.
93 * Testing: Test your change and explain in the commit message *how* your
94 commit was tested. For example adding unittests or in some cases just testing
95 with the existing ones is enough. In any case, mention what testing was
96 performed so reviewers can evaluate whether that's enough testing. In many
97 cases, testing that the Continuous Integration workflow passes is enough.
99 * Make one commit per Pull Request / review, unless there's a good reason not
100 to. If you have multiple changes send multiple Pull Requests and each one can
103 * When addressing comments from reviewers prefer to squash or fixup your
104 edits and force-push your commit. When merging changes into the repository we
105 don't want to include the history of code review back and forth changes or
106 typos. Reviewers can click on the "force-pushed" automatic comment on a Pull
107 Request to see the changes between versions. We use "Rebase and merge" policy
108 to keep a linear git history which is easier to reason about.
110 * Your change must pass the build and test workflows. There's a `ci.sh` script
111 to help building and testing these configurations. See [building and
112 testing](doc/building_and_testing.md) for more details.
114 ### Contributing checklist.
116 * Sign the CLA (only needed once per user, see above).
118 * AUTHORS: You can add your name to the [AUTHORS](AUTHORS) file.
120 * Style guide. Check `./ci.sh lint`.
122 * Meaningful commit description: What and *why*, links to issues, testing
125 * Squashed multiple edits into a single commit.
127 * Upload your changes to your fork and [create a Pull
128 Request](https://docs.github.com/en/github/collaborating-with-issues-and-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request).
130 # Community Guidelines
132 This project follows [Google's Open Source Community
133 Guidelines](https://opensource.google.com/conduct/).