--- /dev/null
+<?php
+
+namespace Drupal\Tests\paragraphs\Kernel;
+
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\KernelTests\KernelTestBase;
+use Drupal\paragraphs\Entity\Paragraph;
+use Drupal\paragraphs\Entity\ParagraphsType;
+
+/**
+ * Tests \Drupal\Paragraphs\Entity\Paragraph::isChanged().
+ *
+ * @group paragraphs
+ */
+class ParagraphsIsChangedTest extends KernelTestBase {
+
+ /**
+ * {@inheritdoc}
+ */
+ public static $modules = [
+ 'paragraphs',
+ 'user',
+ 'system',
+ 'field',
+ 'entity_reference_revisions',
+ 'file',
+ ];
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function setUp() {
+ parent::setUp();
+ $this->installEntitySchema('user');
+ $this->installEntitySchema('paragraph');
+ $this->installSchema('system', ['sequences']);
+ \Drupal::moduleHandler()->loadInclude('paragraphs', 'install');
+
+ // Create a text paragraph type.
+ $paragraph_type = ParagraphsType::create([
+ 'label' => 'text_paragraph',
+ 'id' => 'text_paragraph',
+ ]);
+ $paragraph_type->save();
+ $this->addParagraphsField('text_paragraph', 'text', 'string');
+ }
+
+ /**
+ * Tests the functionality of the isChanged() function.
+ */
+ public function testIsChanged() {
+ // Create a paragraph.
+ $paragraph = Paragraph::create([
+ 'title' => 'Paragraph',
+ 'type' => 'text_paragraph',
+ 'text' => 'Text Paragraph',
+ ]);
+ $this->assertTrue($paragraph->isChanged(), 'The paragraph is a new entity.');
+
+ // Save the paragraph and assert no changes.
+ $paragraph->save();
+ $this->assertFalse($paragraph->isChanged(), 'Paragraph::isChanged() found no changes after the entity has been saved.');
+
+ // Update the revision author field, which should be skipped from checking
+ // for changes in Paragraph::isChanged().
+ $paragraph->setRevisionAuthorId(3);
+ $this->assertFalse($paragraph->isChanged(), 'Paragraph::isChanged() found no changes after updating revision_uid field.');
+
+ $paragraph->set('text', 'New text');
+ $this->assertTrue($paragraph->isChanged(), 'Paragraph::isChanged() found changes after updating text field.');
+ }
+
+ /**
+ * Adds a field to a given paragraph type.
+ *
+ * @param string $paragraph_type_name
+ * Paragraph type name to be used.
+ * @param string $field_name
+ * Paragraphs field name to be used.
+ * @param string $field_type
+ * Type of the field.
+ * @param array $field_edit
+ * Edit settings for the field.
+ */
+ protected function addParagraphsField($paragraph_type_name, $field_name, $field_type, array $field_edit = []) {
+ // Add a paragraphs field.
+ $field_storage = FieldStorageConfig::create([
+ 'field_name' => $field_name,
+ 'entity_type' => 'paragraph',
+ 'type' => $field_type,
+ 'cardinality' => '-1',
+ 'settings' => $field_edit,
+ ]);
+ $field_storage->save();
+ $field = FieldConfig::create([
+ 'field_storage' => $field_storage,
+ 'bundle' => $paragraph_type_name,
+ 'settings' => [
+ 'handler' => 'default:paragraph',
+ 'handler_settings' => ['target_bundles' => NULL],
+ ],
+ ]);
+ $field->save();
+ }
+
+}