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- Step 1: Setup your Environment
- Step 2: Work on your Patch
- Step 3: Submit your Patch
Table of Contents
Patches are the best way to provide a bug fix or to propose enhancements to Symfony.
Before working on Symfony, setup a friendly environment with the following software:
- PHP version 5.5.9 or above.
Before Symfony 2.7, the minimal PHP version was 5.3.3. Before Symfony 3.0, minimal version was 5.3.9. Please keep this in mind, if you are working on a bug fix for earlier versions of Symfony.
Set up your user information with your real name and a working email address:
$ git config --global user.name "Your Name" $ git config --global user.email [email protected]
If you are new to Git, you are highly recommended to read the excellent and free ProGit book.
If your IDE creates configuration files inside the project's directory,
you can use global
.gitignore file (for all projects) or
.git/info/exclude file (per project) to ignore them. See
Windows users: when installing Git, the installer will ask what to do with line endings, and suggests replacing all LF with CRLF. This is the wrong setting if you wish to contribute to Symfony! Selecting the as-is method is your best choice, as Git will convert your line feeds to the ones in the repository. If you have already installed Git, you can check the value of this setting by typing:
$ git config core.autocrlf
This will return either "false", "input" or "true"; "true" and "false" being the wrong values. Change it to "input" by typing:
$ git config --global core.autocrlf input
Replace --global by --local if you want to set it only for the active repository
Get the Symfony source code:
- Create a GitHub account and sign in;
- Fork the Symfony repository (click on the "Fork" button);
- After the "forking action" has completed, clone your fork locally
(this will create a
$ git clone [email protected]:USERNAME/symfony.git
- Add the upstream repository as a remote:
$ cd symfony $ git remote add upstream git://github.com/symfony/symfony.git
Before you start, you must know that all the patches you are going to submit must be released under the MIT license, unless explicitly specified in your commits.
Before working on a patch, you must determine on which branch you need to work:
2.7, if you are fixing a bug for an existing feature or want to make a change that falls into the list of acceptable changes in patch versions (you may have to choose a higher branch if the feature you are fixing was introduced in a later version);
master, if you are adding a new feature.
All bug fixes merged into maintenance branches are also merged into more
recent branches on a regular basis. For instance, if you submit a patch
2.7 branch, the patch will also be applied by the core team on
Each time you want to work on a patch for a bug or on an enhancement, create a topic branch:
$ git checkout -b BRANCH_NAME master
Or, if you want to provide a bugfix for the
2.7 branch, first track the remote
2.7 branch locally:
$ git checkout -t origin/2.7
Then create a new branch off the
2.7 branch to work on the bugfix:
$ git checkout -b BRANCH_NAME 2.7
Use a descriptive name for your branch (
XXX is the
ticket number is a good convention for bug fixes).
The above checkout commands automatically switch the code to the newly created
branch (check the branch you are working on with
If you want to test your code in an existing project that uses
or Symfony components, you can use the
link utility provided in the Git repository
you cloned previously.
This tool scans the
vendor/ directory of your project, finds Symfony packages it
uses, and replaces them by symbolic links to the ones in the Git repository.
$ php link /path/to/your/project
Before running the
link command, be sure that the dependencies of the project you
want to debug are installed by running
composer install inside it.
Work on the code as much as you want and commit as much as you want; but keep in mind the following:
- Read about the Symfony conventions and follow the
coding standards (use
git diff --checkto check for trailing spaces -- also read the tip below);
- Add unit tests to prove that the bug is fixed or that the new feature actually works;
- Try hard to not break backward compatibility (if you must do so, try to provide a compatibility layer to support the old way) -- patches that break backward compatibility have less chance to be merged;
- Do atomic and logically separate commits (use the power of
git rebaseto have a clean and logical history);
- Never fix coding standards in some existing code as it makes the code review more difficult;
- Write good commit messages (see the tip below).
A status is posted below the pull request description with a summary of any problems it detects or any Travis CI build failures.
A good commit message is composed of a summary (the first line),
optionally followed by a blank line and a more detailed description. The
summary should start with the Component you are working on in square
[FrameworkBundle], ...). Use a
added ..., ...) to start the summary and don't
add a period at the end.
When your patch is not about a bug fix (when you add a new feature or change an existing one for instance), it must also include the following:
- An explanation of the changes in the relevant
[BC BREAK]or the
[DEPRECATION]prefix must be used when relevant);
- An explanation on how to upgrade an existing application in the relevant
UPGRADEfile(s) if the changes break backward compatibility or if you deprecate something that will ultimately break backward compatibility.
Whenever you feel that your patch is ready for submission, follow the following steps.
Before submitting your patch, update your branch (needed if it takes you a while to finish your changes):
1 2 3 4 5
$ git checkout master $ git fetch upstream $ git merge upstream/master $ git checkout BRANCH_NAME $ git rebase master
master with the branch you selected previously (e.g.
if you are working on a bugfix
When doing the
rebase command, you might have to fix merge conflicts.
git status will show you the unmerged files. Resolve all the conflicts,
then continue the rebase:
$ git add ... # add resolved files $ git rebase --continue
Check that all tests still pass and push your branch remotely:
$ git push --force origin BRANCH_NAME
You can now make a pull request on the
symfony/symfony GitHub repository.
Take care to point your pull request towards
symfony:2.7 if you want
the core team to pull a bugfix based on the
To ease the core team work, always include the modified components in your pull request message, like in:
[Yaml] fixed something [Form] [Validator] [FrameworkBundle] added something
The default pull request description contains a table which you must fill in with the appropriate answers. This ensures that contributions may be reviewed without needless feedback loops and that your contributions can be included into Symfony as quickly as possible.
Some answers to the questions trigger some more requirements:
- If you answer yes to "Bug fix?", check if the bug is already listed in the Symfony issues and reference it/them in "Fixed tickets";
- If you answer yes to "New feature?", you must submit a pull request to the documentation and reference it under the "Doc PR" section;
- If you answer yes to "BC breaks?", the patch must contain updates to the
- If you answer yes to "Deprecations?", the patch must contain updates to the
- If you answer no to "Tests pass", you must add an item to a todo-list with the actions that must be done to fix the tests;
- If the "license" is not MIT, just don't submit the pull request as it won't be accepted anyway.
If some of the previous requirements are not met, create a todo-list and add relevant items:
1 2 3
- [ ] fix the tests as they have not been updated yet - [ ] submit changes to the documentation - [ ] document the BC breaks
If the code is not finished yet because you don't have time to finish it or because you want early feedback on your work, add an item to todo-list:
- [ ] finish the code - [ ] gather feedback for my changes
As long as you have items in the todo-list, please prefix the pull request title with "[WIP]".
In the pull request description, give as much details as possible about your changes (don't hesitate to give code examples to illustrate your points). If your pull request is about adding a new feature or modifying an existing one, explain the rationale for the changes. The pull request description helps the code review and it serves as a reference when the code is merged (the pull request description and all its associated comments are part of the merge commit message).
In addition to this "code" pull request, you must also send a pull request to the documentation repository to update the documentation when appropriate.
Based on the feedback on the pull request, you might need to rework your
patch. Before re-submitting the patch, rebase with
upstream/2.7, don't merge; and force the push to the origin:
$ git rebase -f upstream/master $ git push --force origin BRANCH_NAME
When doing a
push --force, always specify the branch name explicitly
to avoid messing other branches in the repo (
--force tells Git that
you really want to mess with things so do it carefully).
Moderators earlier asked you to "squash" your commits. This means you will convert many commits to one commit. This is no longer necessary today, because Symfony project uses a proprietary tool which automatically squashes all commits before merging.