diff -u b/core/modules/taxonomy/src/Plugin/migrate/source/d6/TaxonomyVocabularyTranslation.php b/core/modules/taxonomy/src/Plugin/migrate/source/d6/TaxonomyVocabularyTranslation.php
--- b/core/modules/taxonomy/src/Plugin/migrate/source/d6/TaxonomyVocabularyTranslation.php
+++ b/core/modules/taxonomy/src/Plugin/migrate/source/d6/TaxonomyVocabularyTranslation.php
@@ -47,6 +47,7 @@
 
     return $query;
   }
+
   /**
    * {@inheritdoc}
    */
@@ -55,7 +56,7 @@
       'vid' => $this->t('The vocabulary ID.'),
       'language' => $this->t('Language for this field.'),
       'property' => $this->t('Name of property being translated.'),
-      'translation' => $this->t('Translation of either the title or explanation.')
+      'translation' => $this->t('Translation of either the title or explanation.'),
     ];
   }
 
diff -u b/core/modules/taxonomy/tests/src/Kernel/Plugin/migrate/source/d6/VocabularyTranslationTest.php b/core/modules/taxonomy/tests/src/Kernel/Plugin/migrate/source/d6/VocabularyTranslationTest.php
--- b/core/modules/taxonomy/tests/src/Kernel/Plugin/migrate/source/d6/VocabularyTranslationTest.php
+++ b/core/modules/taxonomy/tests/src/Kernel/Plugin/migrate/source/d6/VocabularyTranslationTest.php
@@ -17,114 +17,108 @@
    */
   public static $modules = ['taxonomy', 'migrate_drupal'];
 
-  protected $i18n_strings = [
-    [
-      'lid' => 1,
-      'objectid' => 1,
-      'type' => 'vocabulary',
-      'property' => 'name',
-      'objectindex' => 1,
-      'format' => 0,
-    ],
-    [
-      'lid' => 2,
-      'objectid' => 2,
-      'type' => 'vocabulary',
-      'property' => 'name',
-      'objectindex' => 2,
-      'format' => 0,
-    ],
-  ];
-
-  protected $locales_target = [
-    [
-      'lid' => 1,
-      'language' => 'fr',
-      'translation' => 'fr - vocabulary 1',
-      'plid' => 0,
-      'plural' => 0,
-      'i18n_status' => 0,
-    ],
-    [
-      'lid' => 2,
-      'language' => 'fr',
-      'translation' => 'fr - vocabulary 2',
-      'plid' => 0,
-      'plural' => 0,
-      'i18n_status' => 0,
-    ],
-  ];
-
-  protected $vocabulary = [
-    [
-      'vid' => 1,
-      'name' => 'vocabulary 1',
-      'description' => 'description of vocabulary 1',
-      'help' => 1,
-      'relations' => 1,
-      'hierarchy' => 1,
-      'multiple' => 0,
-      'required' => 0,
-      'tags' => 0,
-      'module' => 'taxonomy',
-      'weight' => 4,
-      'language' => ''
-    ],
-    [
-      'vid' => 2,
-      'name' => 'vocabulary 2',
-      'description' => 'description of vocabulary 2',
-      'help' => 1,
-      'relations' => 1,
-      'hierarchy' => 1,
-      'multiple' => 0,
-      'required' => 0,
-      'tags' => 0,
-      'module' => 'taxonomy',
-      'weight' => 5,
-      'language' => ''
-    ],
-  ];
-
-  protected $expectedResults = [
-    [
-      'vid' => 1,
-      'name' => 'vocabulary 1',
-      'description' => 'description of vocabulary 1',
-      'lid' => '1',
-      'type' => 'vocabulary',
-      'property' => 'name',
-      'objectid' => '1',
-      'lt_lid' => '1',
-      'translation' => 'fr - vocabulary 1',
-      'language' => 'fr',
-    ],
-    [
-      'vid' => 2,
-      'name' => 'vocabulary 2',
-      'description' => 'description of vocabulary 2',
-      'lid' => '2',
-      'type' => 'vocabulary',
-      'property' => 'name',
-      'objectid' => '2',
-      'lt_lid' => '2',
-      'translation' => 'fr - vocabulary 2',
-      'language' => 'fr',
-    ],
-  ];
-
   /**
    * {@inheritdoc}
    */
   public function providerSource() {
     $tests = [];
 
-    $tests[0][0]['i18n_strings'] = $this->i18n_strings;
-    $tests[0][0]['locales_target'] = $this->locales_target;
-    $tests[0][0]['vocabulary'] = $this->vocabulary;
-
-    $tests[0][1] = $this->expectedResults;
-
+    // The source data.
+    $tests[0][0]['i18n_strings'] = [
+      [
+        'lid' => 1,
+        'objectid' => 1,
+        'type' => 'vocabulary',
+        'property' => 'name',
+        'objectindex' => 1,
+        'format' => 0,
+      ],
+      [
+        'lid' => 2,
+        'objectid' => 2,
+        'type' => 'vocabulary',
+        'property' => 'name',
+        'objectindex' => 2,
+        'format' => 0,
+      ],
+    ];
+
+    $tests[0][0]['locales_target'] = [
+      [
+        'lid' => 1,
+        'language' => 'fr',
+        'translation' => 'fr - vocabulary 1',
+        'plid' => 0,
+        'plural' => 0,
+        'i18n_status' => 0,
+      ],
+      [
+        'lid' => 2,
+        'language' => 'fr',
+        'translation' => 'fr - vocabulary 2',
+        'plid' => 0,
+        'plural' => 0,
+        'i18n_status' => 0,
+      ],
+    ];
+
+    $tests[0][0]['vocabulary'] = [
+      [
+        'vid' => 1,
+        'name' => 'vocabulary 1',
+        'description' => 'description of vocabulary 1',
+        'help' => 1,
+        'relations' => 1,
+        'hierarchy' => 1,
+        'multiple' => 0,
+        'required' => 0,
+        'tags' => 0,
+        'module' => 'taxonomy',
+        'weight' => 4,
+        'language' => '',
+      ],
+      [
+        'vid' => 2,
+        'name' => 'vocabulary 2',
+        'description' => 'description of vocabulary 2',
+        'help' => 1,
+        'relations' => 1,
+        'hierarchy' => 1,
+        'multiple' => 0,
+        'required' => 0,
+        'tags' => 0,
+        'module' => 'taxonomy',
+        'weight' => 5,
+        'language' => '',
+      ],
+    ];
+
+    $tests[0]['expected_results'] = [
+      [
+        'vid' => 1,
+        'name' => 'vocabulary 1',
+        'description' => 'description of vocabulary 1',
+        'lid' => '1',
+        'type' => 'vocabulary',
+        'property' => 'name',
+        'objectid' => '1',
+        'lt_lid' => '1',
+        'translation' => 'fr - vocabulary 1',
+        'language' => 'fr',
+      ],
+      [
+        'vid' => 2,
+        'name' => 'vocabulary 2',
+        'description' => 'description of vocabulary 2',
+        'lid' => '2',
+        'type' => 'vocabulary',
+        'property' => 'name',
+        'objectid' => '2',
+        'lt_lid' => '2',
+        'translation' => 'fr - vocabulary 2',
+        'language' => 'fr',
+      ],
+    ];
     return $tests;
   }