Issue #2428087 by jhodgdon, foxtrotcharlie: Boolean field formatter - default choice appears in list twice

core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/BooleanFormatter.php

@@ -71,7 +71,12 @@ class BooleanFormatter extends FormatterBase {
     $formats = [];
     foreach ($this->getOutputFormats() as $format_name => $format) {
       if (is_array($format)) {
-        $formats[$format_name] = implode(' / ', $format);
+        if ($format_name == 'default') {
+          $formats[$format_name] = $this->t('Field settings (@on_label / @off_label)', array('@on_label' => $format[0], '@off_label' => $format[1]));
+        }
+        else {
+          $formats[$format_name] = $this->t('@on_label / @off_label', array('@on_label' => $format[0], '@off_label' => $format[1]));
+        }
       }
       else {
         $formats[$format_name] = $format;

core/modules/field/src/Tests/Boolean/BooleanFormatterSettingsTest.php

@@ -0,0 +1,132 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\field\Tests\Boolean\BooleanFormatterSettingsTest.
+ */
+
+namespace Drupal\field\Tests\Boolean;
+
+use Drupal\Component\Utility\Unicode;
+use Drupal\Component\Utility\String;
+use Drupal\Core\Entity\Display\EntityViewDisplayInterface;
+use Drupal\Core\Entity\FieldableEntityInterface;
+use Drupal\field\Entity\FieldConfig;
+use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\simpletest\WebTestBase;
+
+/**
+ * Tests the Boolean field formatter settings.
+ *
+ * @group field
+ */
+class BooleanFormatterSettingsTest extends WebTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = ['field', 'field_ui', 'text', 'node', 'user'];
+
+  /**
+   * The name of the entity bundle that is created in the test.
+   *
+   * @var string
+   */
+  protected $bundle;
+
+  /**
+   * The name of the Boolean field to use for testing.
+   *
+   * @var string
+   */
+  protected $fieldName;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    // Create a content type. Use Node because it has Field UI pages that work.
+    $type_name = Unicode::strtolower($this->randomMachineName(8)) . '_test';
+    $type = $this->drupalCreateContentType(array('name' => $type_name, 'type' => $type_name));
+    $this->bundle = $type->id();
+
+    $admin_user = $this->drupalCreateUser(array('access content', 'administer content types', 'administer node fields', 'administer node display', 'bypass node access', 'administer nodes'));
+    $this->drupalLogin($admin_user);
+
+    $this->fieldName = Unicode::strtolower($this->randomMachineName(8));
+
+    $field_storage = FieldStorageConfig::create([
+      'field_name' => $this->fieldName,
+      'entity_type' => 'node',
+      'type' => 'boolean',
+    ]);
+    $field_storage->save();
+
+    $instance = FieldConfig::create([
+      'field_storage' => $field_storage,
+      'bundle' => $this->bundle,
+      'label' => $this->randomMachineName(),
+    ]);
+    $instance->save();
+
+    $display = entity_get_display('node', $this->bundle, 'default')
+      ->setComponent($this->fieldName, [
+        'type' => 'boolean',
+        'settings' => [],
+      ]);
+    $display->save();
+  }
+
+  /**
+   * Tests the formatter settings page for the Boolean formatter.
+   */
+  function testBooleanFormatterSettings() {
+    // List the options we expect to see on the settings form. Omit the one
+    // with the Unicode check/x characters, which does not appear to work
+    // well in WebTestBase.
+    $options = array(
+      'Yes / No',
+      'True / False',
+      'On / Off',
+      'Enabled / Disabled',
+      '1 / 0',
+      'Custom',
+    );
+
+    // Define what the "default" option should look like, depending on the
+    // field settings.
+    $default = 'Field settings (@on / @off)';
+
+    // For several different values of the field settings, test that the
+    // options, including default, are shown correctly.
+    $settings = array(
+      array('Yes', 'No'),
+      array('On', 'Off'),
+      array('TRUE', 'FALSE'),
+    );
+
+    foreach ($settings as $values) {
+      // Set up the field settings.
+      $this->drupalGet('admin/structure/types/manage/' . $this->bundle . '/fields/node.' . $this->bundle . '.' . $this->fieldName . '/storage');
+      $this->drupalPostForm(NULL, array(
+        'field_storage[settings][on_label]' => $values[0],
+        'field_storage[settings][off_label]' => $values[1],
+      ), 'Save field settings');
+
+      // Open the Manage Display page and trigger the field settings form.
+      $this->drupalGet('admin/structure/types/manage/' . $this->bundle . '/display');
+      $this->drupalPostAjaxForm(NULL, array(), $this->fieldName . '_settings_edit');
+
+      // Test that the settings options are present in the correct format.
+      foreach ($options as $string) {
+        $this->assertText($string);
+      }
+      $this->assertText(String::format($default, array('@on' => $values[0], '@off' => $values[1])));
+    }
+  }
+
+}