diff --git a/core/modules/field/tests/src/Kernel/Migrate/d6/MigrateFieldFormatterSettingsTest.php b/core/modules/field/tests/src/Kernel/Migrate/d6/MigrateFieldFormatterSettingsTest.php
index 7bf3ad541830caae7b1ed865126e7828dc928fec..7b6e96a308bac0bcd9e40c242212bdf79aee4432 100644
--- a/core/modules/field/tests/src/Kernel/Migrate/d6/MigrateFieldFormatterSettingsTest.php
+++ b/core/modules/field/tests/src/Kernel/Migrate/d6/MigrateFieldFormatterSettingsTest.php
@@ -197,7 +197,7 @@ public function testEntityDisplaySettings() {
     $component = $display->getComponent('field_test_datetime');
     $this->assertIdentical($expected, $component);
     // Test that our Id map has the correct data.
-    $this->assertIdentical(['node', 'story', 'teaser', 'field_test'], $this->getMigration('d6_field_formatter_settings')->getIdMap()->lookupDestinationID(['story', 'teaser', 'node', 'field_test']));
+    $this->assertIdentical(['node', 'story', 'teaser', 'field_test'], $this->getMigration('d6_field_formatter_settings')->getIdMap()->lookupDestinationId(['story', 'teaser', 'node', 'field_test']));
 
     // Test hidden field.
     $this->assertComponentNotExists('node.test_planet.teaser', 'field_test_text_single_checkbox');
diff --git a/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadEntityDisplayTest.php b/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadEntityDisplayTest.php
index 200dc8617a334db7c48944d217ed3c0b27a86ccb..164168312dc71b1e67026e8092b9a803aceb07d7 100644
--- a/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadEntityDisplayTest.php
+++ b/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadEntityDisplayTest.php
@@ -44,7 +44,7 @@ public function testUploadEntityDisplay() {
     $component = $display->getComponent('upload');
     $this->assertTrue(is_null($component));
 
-    $this->assertIdentical(['node', 'page', 'default', 'upload'], $this->getMigration('d6_upload_entity_display')->getIdMap()->lookupDestinationID(['page']));
+    $this->assertIdentical(['node', 'page', 'default', 'upload'], $this->getMigration('d6_upload_entity_display')->getIdMap()->lookupDestinationId(['page']));
   }
 
   /**
diff --git a/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadEntityFormDisplayTest.php b/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadEntityFormDisplayTest.php
index 36e9f1da209cfd9c5cb8dd972bd5ed5f780ce332..43a0ea6e474052c6e26e44373d259681dadceedf 100644
--- a/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadEntityFormDisplayTest.php
+++ b/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadEntityFormDisplayTest.php
@@ -44,7 +44,7 @@ public function testUploadEntityFormDisplay() {
     $component = $display->getComponent('upload');
     $this->assertTrue(is_null($component));
 
-    $this->assertIdentical(['node', 'page', 'default', 'upload'], $this->getMigration('d6_upload_entity_form_display')->getIdMap()->lookupDestinationID(['page']));
+    $this->assertIdentical(['node', 'page', 'default', 'upload'], $this->getMigration('d6_upload_entity_form_display')->getIdMap()->lookupDestinationId(['page']));
   }
 
   /**
diff --git a/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadFieldTest.php b/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadFieldTest.php
index 9ea8cce42475c999941476bdb2ae5559272da658..50322338732556dbb3e5d04347f34f30783f0e09 100644
--- a/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadFieldTest.php
+++ b/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadFieldTest.php
@@ -31,7 +31,7 @@ protected function setUp() {
   public function testUpload() {
     $field_storage = FieldStorageConfig::load('node.upload');
     $this->assertIdentical('node.upload', $field_storage->id());
-    $this->assertIdentical(['node', 'upload'], $this->getMigration('d6_upload_field')->getIdMap()->lookupDestinationID(['']));
+    $this->assertIdentical(['node', 'upload'], $this->getMigration('d6_upload_field')->getIdMap()->lookupDestinationId(['']));
   }
 
 }
diff --git a/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadInstanceTest.php b/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadInstanceTest.php
index 84bd4eb0874592e8308e7400b6e38553e57ea18a..bf5807e68e5809eec62116f54efd5555f69972ce 100644
--- a/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadInstanceTest.php
+++ b/core/modules/file/tests/src/Kernel/Migrate/d6/MigrateUploadInstanceTest.php
@@ -43,7 +43,7 @@ public function testUploadFieldInstance() {
     $field = FieldConfig::load('node.article.upload');
     $this->assertTrue(is_null($field));
 
-    $this->assertIdentical(['node', 'page', 'upload'], $this->getMigration('d6_upload_field_instance')->getIdMap()->lookupDestinationID(['page']));
+    $this->assertIdentical(['node', 'page', 'upload'], $this->getMigration('d6_upload_field_instance')->getIdMap()->lookupDestinationId(['page']));
   }
 
 }
diff --git a/core/modules/migrate/src/Plugin/MigrateIdMapInterface.php b/core/modules/migrate/src/Plugin/MigrateIdMapInterface.php
index 31322a5724e73c1253355a2ea4e55974ef2ff59e..52a57b69f7d28463ce22527a36f6ba47a48765a6 100644
--- a/core/modules/migrate/src/Plugin/MigrateIdMapInterface.php
+++ b/core/modules/migrate/src/Plugin/MigrateIdMapInterface.php
@@ -197,7 +197,7 @@ public function getRowsNeedingUpdate($count);
    *   The source identifier keyed values of the record, e.g. ['nid' => 5], or
    *   an empty array on failure.
    */
-  public function lookupSourceID(array $destination_id_values);
+  public function lookupSourceId(array $destination_id_values);
 
   /**
    * Looks up the destination identifier corresponding to a source key.
diff --git a/core/modules/migrate/src/Plugin/migrate/id_map/NullIdMap.php b/core/modules/migrate/src/Plugin/migrate/id_map/NullIdMap.php
index a44c8388bf88796265adb6d4eb44eb3a7c7a7c66..0e10ea9dfd503f58923369342ede2f205a276285 100644
--- a/core/modules/migrate/src/Plugin/migrate/id_map/NullIdMap.php
+++ b/core/modules/migrate/src/Plugin/migrate/id_map/NullIdMap.php
@@ -48,7 +48,7 @@ public function getRowsNeedingUpdate($count) {
   /**
    * {@inheritdoc}
    */
-  public function lookupSourceID(array $destination_id_values) {
+  public function lookupSourceId(array $destination_id_values) {
     return [];
   }
 
diff --git a/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
index 946b208a101a1c0d696c6d1f440751b514efa66b..fb6c084add75294aba107f103d72f70894f3fd97 100644
--- a/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
+++ b/core/modules/migrate/src/Plugin/migrate/id_map/Sql.php
@@ -529,7 +529,7 @@ public function getRowsNeedingUpdate($count) {
   /**
    * {@inheritdoc}
    */
-  public function lookupSourceID(array $destination_id_values) {
+  public function lookupSourceId(array $destination_id_values) {
     $source_id_fields = $this->sourceIdFields();
     $query = $this->getDatabase()->select($this->mapTableName(), 'map');
     foreach ($source_id_fields as $source_field_name => $idmap_field_name) {
@@ -789,7 +789,7 @@ public function delete(array $source_id_values, $messages_only = FALSE) {
   public function deleteDestination(array $destination_id_values) {
     $map_query = $this->getDatabase()->delete($this->mapTableName());
     $message_query = $this->getDatabase()->delete($this->messageTableName());
-    $source_id_values = $this->lookupSourceID($destination_id_values);
+    $source_id_values = $this->lookupSourceId($destination_id_values);
     if (!empty($source_id_values)) {
       foreach ($this->destinationIdFields() as $field_name => $destination_id) {
         $map_query->condition($destination_id, $destination_id_values[$field_name]);
diff --git a/core/modules/migrate/src/Plugin/migrate/process/MakeUniqueEntityField.php b/core/modules/migrate/src/Plugin/migrate/process/MakeUniqueEntityField.php
index 750903729c818538079c519f3888de0772d64843..10b8dcc3b84a54d1ca3ef8e5cacadb056a1838a5 100644
--- a/core/modules/migrate/src/Plugin/migrate/process/MakeUniqueEntityField.php
+++ b/core/modules/migrate/src/Plugin/migrate/process/MakeUniqueEntityField.php
@@ -134,7 +134,7 @@ protected function exists($value) {
       $idMap = $this->migration->getIdMap();
       foreach ($query->execute() as $id) {
         $dest_id_values[$this->configuration['field']] = $id;
-        if ($idMap->lookupSourceID($dest_id_values)) {
+        if ($idMap->lookupSourceId($dest_id_values)) {
           return TRUE;
         }
       }
diff --git a/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapTest.php b/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapTest.php
index 001e14c74c8ef4edddb6194d7d846cf06dc0e759..d6a965b97386e1725046e9418964048df4e4c5ab 100644
--- a/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapTest.php
+++ b/core/modules/migrate/tests/src/Unit/MigrateSqlIdMapTest.php
@@ -579,7 +579,7 @@ public function testGetRowByDestination() {
   }
 
   /**
-   * Data provider for testLookupSourceIDMapping().
+   * Data provider for testLookupSourceIdMapping().
    *
    * Scenarios to test (for both hits and misses) are:
    * - Single-value destination ID to single-value source ID.
@@ -590,7 +590,7 @@ public function testGetRowByDestination() {
    * @return array
    *   An array of data values.
    */
-  public function lookupSourceIDMappingDataProvider() {
+  public function lookupSourceIdMappingDataProvider() {
     return [
       [1, 1],
       [2, 2],
@@ -607,9 +607,9 @@ public function lookupSourceIDMappingDataProvider() {
    * @param int $num_destination_fields
    *   Number of destination fields to test.
    *
-   * @dataProvider lookupSourceIDMappingDataProvider
+   * @dataProvider lookupSourceIdMappingDataProvider
    */
-  public function testLookupSourceIDMapping($num_source_fields, $num_destination_fields) {
+  public function testLookupSourceIdMapping($num_source_fields, $num_destination_fields) {
     // Adjust the migration configuration according to the number of source and
     // destination fields.
     $this->sourceIds = [];
@@ -635,10 +635,10 @@ public function testLookupSourceIDMapping($num_source_fields, $num_destination_f
     $this->saveMap($row);
     $id_map = $this->getIdMap();
     // Test for a valid hit.
-    $source_id = $id_map->lookupSourceID($destination_id_values);
+    $source_id = $id_map->lookupSourceId($destination_id_values);
     $this->assertSame($expected_result, $source_id);
     // Test for a miss.
-    $source_id = $id_map->lookupSourceID($nonexistent_id_values);
+    $source_id = $id_map->lookupSourceId($nonexistent_id_values);
     $this->assertSame(0, count($source_id));
   }
 
diff --git a/core/modules/migrate/tests/src/Unit/process/DedupeEntityTest.php b/core/modules/migrate/tests/src/Unit/process/DedupeEntityTest.php
index 7b21eff351883e200ee9ff01c8a629bc0c701ded..56ec983485f7053817b46d9aef9e40d22e6e6f0f 100644
--- a/core/modules/migrate/tests/src/Unit/process/DedupeEntityTest.php
+++ b/core/modules/migrate/tests/src/Unit/process/DedupeEntityTest.php
@@ -198,7 +198,7 @@ public function testDedupeMigrated() {
 
     // Entity 'forums' is pre-existing, entity 'test_vocab' was migrated.
     $this->idMap
-      ->method('lookupSourceID')
+      ->method('lookupSourceId')
       ->will($this->returnValueMap([
         [['test_field' => 'forums'], FALSE],
         [['test_field' => 'test_vocab'], ['source_id' => 42]],
diff --git a/core/modules/migrate/tests/src/Unit/process/MakeUniqueEntityFieldTest.php b/core/modules/migrate/tests/src/Unit/process/MakeUniqueEntityFieldTest.php
index 27557d18af8c164c996b24046c60bae56699eacc..fda25de930a4f6ded0b51066eae1281ad3901464 100644
--- a/core/modules/migrate/tests/src/Unit/process/MakeUniqueEntityFieldTest.php
+++ b/core/modules/migrate/tests/src/Unit/process/MakeUniqueEntityFieldTest.php
@@ -197,7 +197,7 @@ public function testMakeUniqueEntityFieldMigrated() {
 
     // Entity 'forums' is pre-existing, entity 'test_vocab' was migrated.
     $this->idMap
-      ->method('lookupSourceID')
+      ->method('lookupSourceId')
       ->will($this->returnValueMap([
         [['test_field' => 'forums'], FALSE],
         [['test_field' => 'test_vocab'], ['source_id' => 42]],
diff --git a/core/modules/node/tests/src/Kernel/Migrate/d6/MigrateNodeTypeTest.php b/core/modules/node/tests/src/Kernel/Migrate/d6/MigrateNodeTypeTest.php
index 9a3e81e150537527f7b9c9d62a5e1acb1c983560..f36aebda01ccf28508f1a2ea41f10d52b9da5162 100644
--- a/core/modules/node/tests/src/Kernel/Migrate/d6/MigrateNodeTypeTest.php
+++ b/core/modules/node/tests/src/Kernel/Migrate/d6/MigrateNodeTypeTest.php
@@ -38,7 +38,7 @@ public function testNodeType() {
     $this->assertIdentical(TRUE, $node_type_page->displaySubmitted());
     $this->assertIdentical(FALSE, $node_type_page->isNewRevision());
     $this->assertIdentical(DRUPAL_OPTIONAL, $node_type_page->getPreviewMode());
-    $this->assertIdentical($id_map->lookupDestinationID(['test_page']), ['test_page']);
+    $this->assertIdentical($id_map->lookupDestinationId(['test_page']), ['test_page']);
 
     // Test we have a body field.
     $field = FieldConfig::loadByName('node', 'test_page', 'body');
@@ -57,7 +57,7 @@ public function testNodeType() {
     $this->assertIdentical(TRUE, $node_type_story->displaySubmitted());
     $this->assertIdentical(FALSE, $node_type_story->isNewRevision());
     $this->assertIdentical(DRUPAL_OPTIONAL, $node_type_story->getPreviewMode());
-    $this->assertIdentical($id_map->lookupDestinationID(['test_story']), ['test_story']);
+    $this->assertIdentical($id_map->lookupDestinationId(['test_story']), ['test_story']);
 
     // Test we don't have a body field.
     $field = FieldConfig::loadByName('node', 'test_story', 'body');
@@ -76,7 +76,7 @@ public function testNodeType() {
     $this->assertIdentical(TRUE, $node_type_event->displaySubmitted());
     $this->assertIdentical(TRUE, $node_type_event->isNewRevision());
     $this->assertIdentical(DRUPAL_OPTIONAL, $node_type_event->getPreviewMode());
-    $this->assertIdentical($id_map->lookupDestinationID(['test_event']), ['test_event']);
+    $this->assertIdentical($id_map->lookupDestinationId(['test_event']), ['test_event']);
 
     // Test we have a body field.
     $field = FieldConfig::loadByName('node', 'test_event', 'body');
diff --git a/core/modules/node/tests/src/Kernel/Migrate/d6/MigrateViewModesTest.php b/core/modules/node/tests/src/Kernel/Migrate/d6/MigrateViewModesTest.php
index f47559275cd81c7209fb2b46e405f513edaa1d39..83de9b0fd80fded059fa3b47f73181c5c0e57357 100644
--- a/core/modules/node/tests/src/Kernel/Migrate/d6/MigrateViewModesTest.php
+++ b/core/modules/node/tests/src/Kernel/Migrate/d6/MigrateViewModesTest.php
@@ -29,7 +29,7 @@ public function testViewModes() {
     $this->assertIdentical(FALSE, is_null($view_mode), 'Preview view mode loaded.');
     $this->assertIdentical('Preview', $view_mode->label(), 'View mode has correct label.');
     // Test the ID map.
-    $this->assertIdentical(['node', 'preview'], $this->getMigration('d6_view_modes')->getIdMap()->lookupDestinationID([1]));
+    $this->assertIdentical(['node', 'preview'], $this->getMigration('d6_view_modes')->getIdMap()->lookupDestinationId([1]));
   }
 
 }
diff --git a/core/modules/path/tests/src/Kernel/Migrate/d6/MigrateUrlAliasTest.php b/core/modules/path/tests/src/Kernel/Migrate/d6/MigrateUrlAliasTest.php
index 0b22cc3ae4750229e7fd0e4b5a522262e8f598ef..59cf3cb1fb0d4c9dbbeef53e15a14079c639f227 100644
--- a/core/modules/path/tests/src/Kernel/Migrate/d6/MigrateUrlAliasTest.php
+++ b/core/modules/path/tests/src/Kernel/Migrate/d6/MigrateUrlAliasTest.php
@@ -68,7 +68,7 @@ public function testUrlAlias() {
     ];
     $path = \Drupal::service('path.alias_storage')->load($conditions);
     $this->assertPath('1', $conditions, $path);
-    $this->assertIdentical($id_map->lookupDestinationID([$path['pid']]), ['1'], "Test IdMap");
+    $this->assertIdentical($id_map->lookupDestinationId([$path['pid']]), ['1'], "Test IdMap");
 
     $conditions = [
       'source' => '/node/2',
diff --git a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateTaxonomyVocabularyTest.php b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateTaxonomyVocabularyTest.php
index 79e188b9e0cca0b5ddeeeab910ad06d671735a9f..1584c5cc738afbea0ce6f0a6c16e36ea990e4083 100644
--- a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateTaxonomyVocabularyTest.php
+++ b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateTaxonomyVocabularyTest.php
@@ -32,7 +32,7 @@ public function testTaxonomyVocabulary() {
     for ($i = 0; $i < 3; $i++) {
       $j = $i + 1;
       $vocabulary = Vocabulary::load("vocabulary_{$j}_i_{$i}_");
-      $this->assertSame($this->getMigration('d6_taxonomy_vocabulary')->getIdMap()->lookupDestinationID([$j]), [$vocabulary->id()]);
+      $this->assertSame($this->getMigration('d6_taxonomy_vocabulary')->getIdMap()->lookupDestinationId([$j]), [$vocabulary->id()]);
       $this->assertSame("vocabulary $j (i=$i)", $vocabulary->label());
       $this->assertSame("description of vocabulary $j (i=$i)", $vocabulary->getDescription());
       $this->assertSame($i, $vocabulary->getHierarchy());
diff --git a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyEntityDisplayTest.php b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyEntityDisplayTest.php
index 5b8a6388745d4da8dcc166a17bd4522514c3b327..6b6ee945c6acb9d3cdb6719aea9dc3bef8d5e5e9 100644
--- a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyEntityDisplayTest.php
+++ b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyEntityDisplayTest.php
@@ -45,7 +45,7 @@ public function testVocabularyEntityDisplay() {
     $this->assertSame('entity_reference_label', $component['type']);
     $this->assertSame(20, $component['weight']);
     // Test the Id map.
-    $this->assertSame(['node', 'article', 'default', 'field_tags'], $this->getMigration('d6_vocabulary_entity_display')->getIdMap()->lookupDestinationID([4, 'article']));
+    $this->assertSame(['node', 'article', 'default', 'field_tags'], $this->getMigration('d6_vocabulary_entity_display')->getIdMap()->lookupDestinationId([4, 'article']));
 
     // Tests that a vocabulary named like a D8 base field will be migrated and
     // prefixed with 'field_' to avoid conflicts.
diff --git a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyEntityFormDisplayTest.php b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyEntityFormDisplayTest.php
index 2c96e51760084502714fecc75a7e8a30cb910167..7cfc306a98cd397571a634ee24bd545296974467 100644
--- a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyEntityFormDisplayTest.php
+++ b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyEntityFormDisplayTest.php
@@ -45,7 +45,7 @@ public function testVocabularyEntityFormDisplay() {
     $this->assertSame('options_select', $component['type']);
     $this->assertSame(20, $component['weight']);
     // Test the Id map.
-    $this->assertSame(['node', 'article', 'default', 'field_tags'], $this->getMigration('d6_vocabulary_entity_form_display')->getIdMap()->lookupDestinationID([4, 'article']));
+    $this->assertSame(['node', 'article', 'default', 'field_tags'], $this->getMigration('d6_vocabulary_entity_form_display')->getIdMap()->lookupDestinationId([4, 'article']));
 
     // Test the term widget tags setting.
     $entity_form_display = EntityFormDisplay::load('node.story.default');
diff --git a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyFieldInstanceTest.php b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyFieldInstanceTest.php
index 26cd7f581a4cf72cbf1c9a1f0f93277c96d3b6c9..77cb3e9069d8f5a3a12770994a5891cec730aced 100644
--- a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyFieldInstanceTest.php
+++ b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyFieldInstanceTest.php
@@ -58,7 +58,7 @@ public function testVocabularyFieldInstance() {
     $this->assertSame(['field_tags'], $settings['handler_settings']['target_bundles'], 'The target_bundles handler setting is correct.');
     $this->assertSame(TRUE, $settings['handler_settings']['auto_create'], 'The "auto_create" setting is correct.');
 
-    $this->assertSame(['node', 'article', 'field_tags'], $this->getMigration('d6_vocabulary_field_instance')->getIdMap()->lookupDestinationID([4, 'article']));
+    $this->assertSame(['node', 'article', 'field_tags'], $this->getMigration('d6_vocabulary_field_instance')->getIdMap()->lookupDestinationId([4, 'article']));
 
     // Test the the field vocabulary_1_i_0_.
     $field_id = 'node.story.field_vocabulary_1_i_0_';
diff --git a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyFieldTest.php b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyFieldTest.php
index d294ec481d63622e4782c4e8d89d477accc6f973..fa5c7f3a16461df7769e5e7413b09f736fdaa661 100644
--- a/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyFieldTest.php
+++ b/core/modules/taxonomy/tests/src/Kernel/Migrate/d6/MigrateVocabularyFieldTest.php
@@ -39,7 +39,7 @@ public function testVocabularyField() {
     $this->assertSame('taxonomy_term', $settings['target_type'], "Target type is correct.");
     $this->assertSame(1, $field_storage->getCardinality(), "Field cardinality in 1.");
 
-    $this->assertSame(['node', 'field_tags'], $this->getMigration('d6_vocabulary_field')->getIdMap()->lookupDestinationID([4]), "Test IdMap");
+    $this->assertSame(['node', 'field_tags'], $this->getMigration('d6_vocabulary_field')->getIdMap()->lookupDestinationId([4]), "Test IdMap");
 
     // Tests that a vocabulary named like a D8 base field will be migrated and
     // prefixed with 'field_' to avoid conflicts.