Guarantee the uniqueness of the migrated paragraph types

Is there another patch you're also using? It looks like the migrations themselves are succeeding but the field collection field itself isn't getting created (I would expect as a paragraphs field).

I'm using the migrate_upgrade module to generate configuration if that helps.

Initial review, trying to understand it all:

1. +++ b/migrations/d7_field_collection.yml
   @@ -8,7 +8,11 @@ deriver: Drupal\paragraphs\Plugin\migrate\D7FieldCollectionItemDeriver
   -  type: bundle
   +  type:
   +    plugin: migration_lookup
   +    migration: d7_field_collection_type
   +    no_stub: true
   +    source: field_name
   

   🤔 If this were a straightforward "use lookup instead of migrating blindly" case, I expected source: bundle, but obviously it's using source: field_name. Why is that?

2. +++ b/migrations/d7_field_collection_type.yml
   @@ -6,8 +6,25 @@ migration_tags:
   -  id: bundle
   +  id:
   +    -
   +      plugin: callback
   +      callable: preg_replace
   +      source:
   +        - constants/field_prefix_regex
   +        - constants/field_prefix_replacement
   +        - field_name
   +      unpack_source: true
   +    -
   +      plugin: make_unique_entity_field
   +      entity_type: paragraphs_type
   +      field: id
   +      postfix: _
   +      length: 29
   

   😯

3. +++ b/migrations/d7_paragraphs.yml
   @@ -8,7 +8,11 @@ deriver: Drupal\paragraphs\Plugin\migrate\D7ParagraphsItemDeriver
   -  type: bundle
   +  type:
   +    plugin: migration_lookup
   +    migration: d7_paragraphs_type
   +    no_stub: true
   +    source: bundle
   

   See and here, unlike in point 1, it does do what I expect.

   Why is that?

4. +++ b/src/MigrationPluginsAlterer.php
   @@ -46,9 +57,22 @@ final class MigrationPluginsAlterer {
   +          // From Drupal core 9.1.4+, the only field migration which needs the
   +          // bundle process alters is 'd7_field_instance', because the formatter
   +          // and the widget migration are using migration lookup for determining
   +          // the destination bundle.
   +          // @see https://drupal.org/i/2565931
   +          if (
   +            (
   +              version_compare(\Drupal::VERSION, '9.1.4', 'lt') &&
   +              \Drupal::VERSION !== '9.1.x-dev'
   

   👏 Wow … such attention to cross-version compatibility!

5. +++ b/tests/src/Kernel/migrate/FieldCollectionItemRevisionSourceTest.php
   @@ -29,7 +29,6 @@ class FieldCollectionItemRevisionSourceTest extends MigrateSqlSourceTestBase {
   -        'bundle' => 'field_collection_field',
   
   +++ b/tests/src/Kernel/migrate/FieldCollectionItemSourceTest.php
   @@ -29,7 +29,6 @@ class FieldCollectionItemSourceTest extends MigrateSqlSourceTestBase {
   -        'bundle' => 'field_collection_field',
   
   @@ -41,7 +40,6 @@ class FieldCollectionItemSourceTest extends MigrateSqlSourceTestBase {
   -        'bundle' => 'field_collection_field',
            'archived' => '0',
   

   Wait, was this data simply wrong in the fixture?! 😨

Fixes for the migration prefixes added by migrate_upgrade, based on #3063273: BlockPluginId process plugin hard codes migrations breaking migrate_upgrade configuration.

Ahhh it's the tests manually creating the instances... I'm not going to be able to fix those for a couple of days.

The patch won't apply anymore since the code was changed in #3203739: Paragraphs migrations broken in Drupal >=9.1.4

Rerolling patch just without fixing the tests.
BTW: without this patch I got into this isuue #3192993: [migrate_upgrade compatibility] d7_field_instance upgrade fails due to redundant 'field_' prefix removal on bundle.

Trying to fix tests

🤷🏻‍♂️

Using this patch along with latest dev, the paragraph bundle label/description is no longer created.

This config was removed from my exported migration configuration:

  label:
    -
      plugin: get
      source: name
  description:
    -
      plugin: get
      source: description

@KarlShea It looks like #15 clobbered the label/description config

Reroll

Whoops

1. +++ b/src/MigrationPluginsAlterer.php
   @@ -46,9 +57,22 @@ final class MigrationPluginsAlterer {
   +            $migration['id'] === 'd7_field_instance'
   

   I applied #3226658: Guarantee the uniqueness of the migrated paragraph types, adjusted my existing migrate_plus migration entities for field_collection_items and field_collection_type to include the new process plugin, and that did remove messages in field instance. Similar results to @vlad.dancer's comment in #3192993: [migrate_upgrade compatibility] d7_field_instance upgrade fails due to redundant 'field_' prefix removal on bundle (comment #23).

   Field widget settings and field formatter settings migrations still generated messages regarding Missing bundle entity, entity type paragraphs_type.

   I think that expanding the migration id to include 'd7_field_instance_widget' and 'd7_field_formatter_settings' might help with that.

2. +++ b/src/Plugin/migrate/process/FieldCollectionFieldInstanceSettings.php
   @@ -14,7 +18,57 @@ use Drupal\paragraphs\Plugin\migrate\field\FieldCollection;
   +  ¶
   ...
   +  ¶
   ...
   +  ¶
   
   @@ -25,12 +79,17 @@ class FieldCollectionFieldInstanceSettings extends ProcessPluginBase {
   +      ¶
   

   Nit: trailing white spaces should be removed