Migrate D6 user reference fields to D8 entity reference field storage config entities

Take this too as I started with node reference.

Closing in favour of #2447727: Add base class for migrating reference fields.

In the name of sanity and scope control, we're splitting #2447727: Add base class for migrating reference fields back out into smaller issues. This is now resurrected and postponed on that.

Users must migrate
For completeness of Migrate
Gentlefolk...BEHOLD!

Seems a re-title would be in order.

1. +++ b/core/modules/migrate_drupal/tests/fixtures/drupal6.php
   @@ -603,6 +603,21 @@
   +$connection->insert('batch')
   

   What's this from?

2. +++ b/core/modules/migrate_drupal/tests/fixtures/drupal6.php
   @@ -42992,7 +43162,7 @@
   +  'changed' => '1494966544',
   
   @@ -43577,7 +43747,7 @@
   -  'timestamp' => '1493066711',
   +  'timestamp' => '1494966544',
   
   @@ -45087,10 +45257,10 @@
   +  'status' => '1',
   ...
   +  'schema_version' => '6002',
   
   @@ -46394,8 +46564,8 @@
   +  'access' => '1494966478',
   +  'login' => '1494966280',
   
   @@ -47476,7 +47646,7 @@
   +  'value' => 'a:16:{i:0;s:14:"misc/jquery.js";i:1;s:14:"misc/drupal.js";i:2;s:19:"misc/tableheader.js";s:10:"refresh:fr";s:7:"waiting";s:10:"refresh:zu";s:7:"waiting";i:3;s:17:"misc/tabledrag.js";i:4;s:32:"sites/all/modules/cck/content.js";i:5;s:16:"misc/textarea.js";i:6;s:16:"misc/collapse.js";i:7;s:12:"misc/form.js";i:8;s:19:"misc/tableselect.js";i:9;s:20:"modules/user/user.js";i:10;s:20:"misc/autocomplete.js";i:11;s:19:"misc/jquery.form.js";i:12;s:12:"misc/ahah.js";i:13;s:14:"misc/teaser.js";}',
   

   Seems like a few stray lines here.

Well, when I manipulate the fixture, I install Drupal 6 and do what I would normally do to make the necessary modifications (i.e., standard procedure for manipulating the fixture). Whatever changes that causes, I just roll into the patch -- I try to let them come through as untouched as possible. So I'm not sure those lines are any cause for concern.

This should fix the broken tests.

Assigning to myself to review this week.

All my concerns are addressed. RTBC.

+++ b/core/modules/field/src/Plugin/migrate/process/d6/FieldSettings.php
+++ b/core/modules/field/src/Plugin/migrate/process/d6/FieldSettings.php
@@ -21,22 +21,24 @@ class FieldSettings extends ProcessPluginBase {

@@ -21,22 +21,24 @@ class FieldSettings extends ProcessPluginBase {
    * Get the field default/mapped settings.
    */
   public function transform($value, MigrateExecutableInterface $migrate_executable, Row $row, $destination_property) {
-    list($field_type, $global_settings) = $value;
-    return $this->getSettings($field_type, $global_settings);
+    list($field_type, $global_settings, $original_field_type) = $value;
+    return $this->getSettings($field_type, $global_settings, $original_field_type);
   }
 
   /**
    * Merge the default D8 and specified D6 settings.
    *
    * @param string $field_type
-   *   The field type.
+   *   The destination field type.
    * @param array $global_settings
    *   The field settings.
+   * @param string $original_field_type
+   *   The original field type before migration.
    *
    * @return array
    *   A valid array of settings.
    */
-  public function getSettings($field_type, $global_settings) {
+  public function getSettings($field_type, $global_settings, $original_field_type) {
     $max_length = isset($global_settings['max_length']) ? $global_settings['max_length'] : '';
     $max_length = empty($max_length) ? 255 : $max_length;
     $allowed_values = [];

Do we need to worry about the additional $original_field_type argument? Can it default to NULL - looks like it's actually optional.

Nice find. This oughta do the trick!

This looks good. I wondered what happened with list() if there weren't enough values passed to it and if the count stuff was necessary. It is, otherwise you result in Notice: Undefined index: 2.

Committed/pushed to 8.4.x and cherry-picked to 8.3.x. Thanks!