generic bool type check in checkbox control

Author: mvorisek

src/Form/Control/Checkbox.php

@@ -33,12 +33,6 @@ public function __construct($label = [])
 
     protected function init(): void
     {
-        // TODO exception should be generalized for type acceptable for any form control
-        if ($this->entityField && $this->entityField->getField()->type !== 'boolean') {
-            throw (new Exception('Checkbox form control requires field with boolean type'))
-                ->addMoreInfo('type', $this->entityField->getField()->type);
-        }
-
         parent::init();
 
         // checkboxes are annoying because they don't send value when they are
@@ -57,6 +51,12 @@ protected function renderView(): void
             $this->template->set('Content', $this->label);
         }
 
+        if ($this->entityField && !is_bool($this->entityField->get() ?? false)) {
+            throw (new Exception('Checkbox form control requires field with boolean type'))
+                ->addMoreInfo('type', $this->entityField->getField()->type)
+                ->addMoreInfo('value', $this->entityField->get());
+        }
+
         if ($this->entityField ? $this->entityField->get() : $this->content) {
             $this->template->dangerouslySetHtml('checked', 'checked="checked"');
         }

tests/FormTest.php

@@ -6,6 +6,7 @@
 
 use Atk4\Core\Phpunit\TestCase;
 use Atk4\Data\Model;
+use Atk4\Data\Model\EntityFieldPair;
 use Atk4\Data\ValidationException;
 use Atk4\Ui\App;
 use Atk4\Ui\Callback;
@@ -226,6 +227,22 @@ public function testNoDisabledAttrWithHiddenType(): void
         self::assertStringNotContainsString('readonly', $input->render());
     }
 
+    public function testCheckboxWithNonBooleanException(): void
+    {
+        $input = new Form\Control\Checkbox();
+        $input->setApp($this->createApp());
+        $input->invokeInit();
+
+        $m = new Model();
+        $m->addField('foo');
+        $input->entityField = new EntityFieldPair($m->createEntity(), 'foo');
+        $input->entityField->set('1');
+
+        $this->expectException(Exception::class);
+        $this->expectExceptionMessage('Checkbox form control requires field with boolean type');
+        $input->render();
+    }
+
     public function testUploadNoUploadCallbackException(): void
     {
         $input = new Form\Control\Upload();