feature #21780 [DX] [Form] Add helper method to register form extensions during unit testing (pierredup)

This PR was squashed before being merged into the 3.3-dev branch (closes #21780).

Discussion
----------

[DX] [Form] Add helper method to register form extensions during unit testing

| Q             | A
| ------------- | ---
| Branch?       | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | N/A
| License       | MIT
| Doc PR        | symfony/symfony-docs#7578

Add helper method to register form extensions during unit testing, so it's easier to register custom form type extensions, form types, or type guessers

Commits
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bab562a987 [DX] [Form] Add helper method to register form extensions during unit testing

Author: fabpot

Test/FormIntegrationTestCase.php

@@ -29,11 +29,29 @@ protected function setUp()
     {
         $this->factory = Forms::createFormFactoryBuilder()
             ->addExtensions($this->getExtensions())
+            ->addTypeExtensions($this->getTypedExtensions())
+            ->addTypes($this->getTypes())
+            ->addTypeGuessers($this->getTypeGuessers())
             ->getFormFactory();
     }
 
     protected function getExtensions()
     {
         return array();
     }
+
+    protected function getTypedExtensions()
+    {
+        return array();
+    }
+
+    protected function getTypes()
+    {
+        return array();
+    }
+
+    protected function getTypeGuessers()
+    {
+        return array();
+    }
 }