Submitting a Patch

Patches are the best way to provide a bug fix or to propose enhancements to Symfony2.

Step 1: Setup your Environment

Install the Software Stack

Before working on Symfony2, setup a friendly environment with the following software:

  • Git;
  • PHP version 5.3.2 or above;
  • PHPUnit 3.5.11 or above.

Configure Git

Set up your user information with your real name and a working email address:

$ git config --global "Your Name"
$ git config --global


If you are new to Git, we highly recommend you to read the excellent and free ProGit book.


Windows users: when installing Git, the installer will ask what to do with line endings and suggests to replace all Lf by 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. Set it to another value 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

Get the Symfony2 source code:

  • Create a GitHub account and sign in;
  • Fork the Symfony2 repository (click on the “Fork” button);
  • After the “hardcore forking action” has completed, clone your fork locally (this will create a symfony directory):
$ git clone
  • Add the upstream repository as remote:
$ cd symfony
$ git remote add upstream git://

Check that the current Tests pass

Now that Symfony2 is installed, check that all unit tests pass for your environment as explained in the dedicated document.

Step 2: Work on your Patch

The License

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.

Choose the right Branch

Before working on a patch, you must determine on which branch you need to work. The branch should be based on the master branch if you want to add a new feature. But if you want to fix a bug, use the oldest but still maintained version of Symfony where the bug happens (like 2.0).


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 for the 2.0 branch, the patch will also be applied by the core team on the master branch.

Create a Topic Branch

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 2.0 branch, first track the remote 2.0 branch locally:

$ git checkout -t origin/2.0

Then create a new branch off the 2.0 branch to work on the bugfix:

$ git checkout -b BRANCH_NAME 2.0


Use a descriptive name for your branch (ticket_XXX where 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 git branch).

Work on your Patch

Work on the code as much as you want and commit as much as you want; but keep in mind the following:

  • Follow the coding standards (use git diff –check to 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 rebase to have a clean and logical history);
  • Squash irrelevant commits that are just about fixing coding standards or fixing typos in your own code;
  • Never fix coding standards in some existing code as it makes the code review more difficult;
  • Write good commit messages (see the tip below).


You can check the coding standards of your patch by running the following [script]( [src](

$ cd /path/to/symfony/src
$ php symfony-cs-fixer.phar fix . Symfony20Finder


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 brackets ([DependencyInjection], [FrameworkBundle], ...). Use a verb (fixed ..., added ..., ...) to start the summary and don’t add a period at the end.

Prepare your Patch for Submission

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 CHANGELOG file(s);
  • An explanation on how to upgrade an existing application in the relevant UPGRADE file(s) if the changes break backward compatibility.

Step 3: Submit your Patch

Whenever you feel that your patch is ready for submission, follow the following steps.

Rebase your Patch

Before submitting your patch, update your branch (needed if it takes you a while to finish your changes):

$ git checkout master
$ git fetch upstream
$ git merge upstream/master
$ git checkout BRANCH_NAME
$ git rebase master


Replace master with 2.0 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 origin BRANCH_NAME

Make a Pull Request

You can now make a pull request on the symfony/symfony Github repository.


Take care to point your pull request towards symfony:2.0 if you want the core team to pull a bugfix based on the 2.0 branch.

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


Please use the title with “[WIP]” if the submission is not yet completed or the tests are incomplete or not yet passing.

The pull request description must include the following check list to ensure that contributions may be reviewed without needless feedback loops and that your contributions can be included into Symfony2 as quickly as possible:

Bug fix: [yes|no]
Feature addition: [yes|no]
Backwards compatibility break: [yes|no]
Symfony2 tests pass: [yes|no]
Fixes the following tickets: [comma separated list of tickets fixed by the PR]
Todo: [list of todos pending]
License of the code: MIT
Documentation PR: [The reference to the documentation PR if any]

An example submission could now look as follows:

Bug fix: no
Feature addition: yes
Backwards compatibility break: no
Symfony2 tests pass: yes
Fixes the following tickets: #12, #43
Todo: -
License of the code: MIT
Documentation PR: symfony/symfony-docs#123

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.

Rework your Patch

Based on the feedback on the pull request, you might need to rework your patch. Before re-submitting the patch, rebase with upstream/master or upstream/2.0, don’t merge; and force the push to the origin:

$ git rebase -f upstream/master
$ git push -f 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).

Often, moderators will ask you to “squash” your commits. This means you will convert many commits to one commit. To do this, use the rebase command:

$ git rebase -i HEAD~3
$ git push -f origin BRANCH_NAME

The number 3 here must equal the amount of commits in your branch. After you type this command, an editor will popup showing a list of commits:

pick 1a31be6 first commit
pick 7fc64b4 second commit
pick 7d33018 third commit

To squash all commits into the first one, remove the word “pick” before the second and the last commits, and replace it by the word “squash” or just “s”. When you save, git will start rebasing, and if successful, will ask you to edit the commit message, which by default is a listing of the commit messages of all the commits. When you finish, execute the push command.


To automatically get your feature branch tested, you can add your fork to Just login using your account and then simply flip a single switch to enable automated testing. In your pull request, instead of specifying “Symfony2 tests pass: [yes|no]”, you can link to the status icon. For more details, see the Getting Started Guide. This could easily be done by clicking on the wrench icon on the build page of Travis. First select your feature branch and then copy the markdown to your PR description.