diff --git a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermUnitTest.php b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermUnitTest.php
index 83132c3..3f0db8a 100644
--- a/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermUnitTest.php
+++ b/core/modules/taxonomy/lib/Drupal/taxonomy/Tests/TermUnitTest.php
@@ -104,5 +104,21 @@ function testTaxonomyVocabularyTree() {
     $this->assertEqual(2, $depth_count[1], 'Two elements in taxonomy tree depth 1.');
     $this->assertEqual(2, $depth_count[2], 'Two elements in taxonomy tree depth 2.');
     $this->assertEqual(1, $depth_count[3], 'One element in taxonomy tree depth 3.');
+
+    // Count parents of $term[2].
+    $parents = taxonomy_term_load_parents($term[2]->id());
+    $this->assertEqual(2, count($parents), 'The term has two parents.');
+
+    // Count parents of $term[3].
+    $parents = taxonomy_term_load_parents($term[3]->id());
+    $this->assertEqual(1, count($parents), 'The term has one parent.');
+
+    // Identify all ancestors of $term[2].
+    $ancestors = taxonomy_term_load_parents_all($term[2]->id());
+    $this->assertEqual(4, count($ancestors), 'The term has four ancestors including the term itself.');
+
+    // Identify all ancestors of $term[3].
+    $ancestors = taxonomy_term_load_parents_all($term[3]->id());
+    $this->assertEqual(5, count($ancestors), 'The term has five ancestors including the term itself.');
   }
 }