Symfony 3.4. overwrite class Symfony\Component\Form

Question

i need to overwrite the function "public function submit($submittedData, $clearMissing = true)" in Symfony\Component\Form.

I can overwrite the "RequestHandlerInterface" but not the form component.

Background: There is a problem with choiceTypes if you submit with Patch-Method (github.com/symfony/symfony/issues/17799). So i want to insert this line into the submit function:

$clearMissing = $this->getConfig()->getOption('expanded', false) ?: $clearMissing;

Answer 1

You can patch the Form class directly as suggested here: https://github.com/symfony/symfony/issues/17799#issuecomment-184473725

---

The only problem is: How to make this change permanent for you project?

I ended up creating a patch for the form class. On Linux and supposing you are using git it works something like this:

1. Open a terminal in your project root directory

2. Add the form class to your git repository

   git add vendor/symfony/symfony/src/Symfony/Component/Form/Form.php
   

3. Patch the form class as described above

4. Create a patch

   git diff > form.patch
   

5. Remove the form class from you git repository

   git rm --cached vendor/symfony/symfony/src/Symfony/Component/Form/Form.php
   

6. Somehow incorporate the patch in your project update process. For my project I wrote a small script that runs after every composer install or composer update.

   #!/bin/sh
   
   # apply form component patch to fix HTTP PATCH issue with ChoiceType
   # run after composer install/update
   patch -p1 -N -r /dev/null < form.patch
   

The options for the patch command are chosen such that there will be no interaction or other side effects in case the patch was already applied.

---

form.patch itself looks something like this:

diff --git a/vendor/symfony/symfony/src/Symfony/Component/Form/Form.php b/vendor/symfony/symfony/src/Symfony/Component/Form/Form.php
index 67fd234f..27ed9e81 100644
--- a/www/vendor/symfony/symfony/src/Symfony/Component/Form/Form.php
+++ b/www/vendor/symfony/symfony/src/Symfony/Component/Form/Form.php
@@ -553,6 +553,10 @@ class Form implements \IteratorAggregate, FormInterface
                 $submittedData = $event->getData();
             }

+            // HTTP PATCH fix for ChoiceType
+            // https://github.com/symfony/symfony/issues/17799#issuecomment-184473725
+            $clearMissing = $this->getConfig()->getOption('expanded', false) ?: $clearMissing;
+
             // Check whether the form is compound.
             // This check is preferable over checking the number of children,
             // since forms without children may also be compound.