From 5bb5ef80ede8d75f2de05c8aaf367925269a14de Mon Sep 17 00:00:00 2001
From: Loz Calver <lozcalver@bigfork.co.uk>
Date: Wed, 9 Jun 2021 17:26:43 +0100
Subject: [PATCH] FIX: Form::defaultAction() didn't work if actions were in
 CompositeFields (fixes #9975)

---
 src/Forms/Form.php           |  4 +++-
 tests/php/Forms/FormTest.php | 19 ++++++++++++++++++-
 2 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/src/Forms/Form.php b/src/Forms/Form.php
index 1d3516954..5718b1f52 100644
--- a/src/Forms/Form.php
+++ b/src/Forms/Form.php
@@ -1682,7 +1682,9 @@ class Form extends ViewableData implements HasRequestHandler
     public function defaultAction()
     {
         if ($this->hasDefaultAction && $this->actions) {
-            return $this->actions->first();
+            return $this->actions->flattenFields()->filterByCallback(function ($field) {
+                return $field instanceof FormAction;
+            })->first();
         }
         return null;
     }
diff --git a/tests/php/Forms/FormTest.php b/tests/php/Forms/FormTest.php
index b31a4a254..2b3b3a4ee 100644
--- a/tests/php/Forms/FormTest.php
+++ b/tests/php/Forms/FormTest.php
@@ -7,6 +7,7 @@ use SilverStripe\Control\HTTPRequest;
 use SilverStripe\Control\Session;
 use SilverStripe\Dev\CSSContentParser;
 use SilverStripe\Dev\FunctionalTest;
+use SilverStripe\Forms\CompositeField;
 use SilverStripe\Forms\DateField;
 use SilverStripe\Forms\DatetimeField;
 use SilverStripe\Forms\FieldList;
@@ -23,7 +24,6 @@ use SilverStripe\Forms\Tests\FormTest\ControllerWithStrictPostCheck;
 use SilverStripe\Forms\Tests\FormTest\Player;
 use SilverStripe\Forms\Tests\FormTest\Team;
 use SilverStripe\Forms\Tests\FormTest\TestController;
-use SilverStripe\Forms\Tests\ValidatorTest\TestValidator;
 use SilverStripe\Forms\TextareaField;
 use SilverStripe\Forms\TextField;
 use SilverStripe\Forms\TimeField;
@@ -338,6 +338,23 @@ class FormTest extends FunctionalTest
         );
     }
 
+    public function testDefaultAction()
+    {
+        $form = Form::create(Controller::curr(), 'Form', new FieldList(), new FieldList(
+            new FormAction('doForm', 'Form Action')
+        ));
+        $this->assertNotNull($form->defaultAction());
+        $this->assertEquals('action_doForm', $form->defaultAction()->getName());
+
+        $form = Form::create(Controller::curr(), 'AnotherForm', new FieldList(), new FieldList(
+            new CompositeField(
+                new FormAction('doAnotherForm', 'Another Form Action')
+            )
+        ));
+        $this->assertNotNull($form->defaultAction());
+        $this->assertEquals('action_doAnotherForm', $form->defaultAction()->getName());
+    }
+
     public function testLoadDataFromIgnoreFalseish()
     {
         $form = new Form(