--- /dev/null
+<?php
+
+namespace Drupal\Tests\migrate_plus\Unit\process;
+
+use Drupal\Tests\migrate\Unit\process\MigrateProcessTestCase;
+use Drupal\migrate_plus\Plugin\migrate\process\SingleValue;
+
+/**
+ * @coversDefaultClass \Drupal\migrate_plus\Plugin\migrate\process\SingleValue
+ * @group migrate
+ */
+class SingleValueTest extends MigrateProcessTestCase {
+
+ /**
+ * {@inheritdoc}
+ */
+ protected function setUp() {
+ $this->plugin = new SingleValue([], 'single_value', []);
+ parent::setUp();
+ }
+
+ /**
+ * Test input treated as single value output.
+ */
+ public function testTreatAsSingle() {
+ $value = ['v1', 'v2', 'v3'];
+ $output = $this->plugin->transform($value, $this->migrateExecutable, $this->row, 'destinationproperty');
+ $this->assertSame($output, $value);
+ $this->assertFalse($this->plugin->multiple());
+ }
+
+}