Remove ability to have custom relationship pre-loaders for now

docs/relationships.md

@@ -67,30 +67,6 @@ $type->hasOne('user')
     ->dontLoad();
 ```
 
-### Custom Loading Logic
-
-Instead of using the adapter's eager-loading logic, you may wish to define your own for a relationship. You can do so using the `load` method. 
-
-Beware that this can be complicated as eager-loading always takes place on the set of models at the root level of the document; these are passed as the first parameter. The second parameter is an array of the `Relationship` objects that make up the nested inclusion trail leading to the current relationship. 
-
-So, for example, if a request was made to `GET /categories?include=latestPost.user`, then the custom loading logic for the `user` relationship might look like this:
-
-```php
-$api->resource('categories', new EloquentAdapter(Models\Category::class), function (Type $type) {
-    $type->hasOne('latestPost')->type('posts')->includable(); // 1
-});
-
-$api->resource('posts', new EloquentAdapter(Models\Post::class), function (Type $type) {
-    $type->hasOne('user') // 2
-        ->includable()
-        ->load(function (array $models, array $relationships, Context $context) {
-            // Since this request is to the `GET /categories` endpoint, $models
-            // will be an array of Category models, and $relationships will be
-            // an array containing the objects [1, 2] above.
-        });
-});
-```
-
 ## Polymorphic Relationships
 
 Define a polymorphic relationship using the `polymorphic` method. Optionally you may provide an array of allowed resource types:

src/Endpoint/Concerns/IncludesData.php

@@ -103,12 +103,9 @@ trait IncludesData
 
             $nextRelationshipPath = array_merge($relationshipPath, [$field]);
 
-            if ($load = $field->getLoad()) {
+            if ($field->shouldLoad()) {
                 $type = $field->getType();
 
-                if (is_callable($load)) {
-                    $load($models, $nextRelationshipPath, $field->hasLinkage(), $context);
-                } else {
                 if (is_string($type)) {
                     $relatedResource = $this->api->getResource($type);
                     $scope = function ($query) use ($context, $field, $relatedResource) {
@@ -135,7 +132,6 @@ trait IncludesData
                 }
 
                 $adapter->load($models, $nextRelationshipPath, $scope, $field->hasLinkage());
-                }
 
                 if (isset($include[$name]) && is_string($type)) {
                     $relatedResource = $this->api->getResource($type);

src/Schema/Relationship.php

@@ -70,13 +70,10 @@ abstract class Relationship extends Field
 
     /**
      * Allow the relationship data to be eager-loaded into the model collection.
-     *
-     * This is used to prevent the n+1 query problem. If null, the adapter will
-     * be used to eager-load relationship data into the model collection.
      */
-    public function load(callable $callback = null)
+    public function load()
     {
-        $this->load = $callback ?: true;
+        $this->load = true;
 
         return $this;
     }
@@ -159,7 +156,7 @@ abstract class Relationship extends Field
     /**
      * @return bool|callable
      */
-    public function getLoad()
+    public function shouldLoad()
     {
         return $this->load;
     }

tests/feature/RelationshipInclusionTest.php

@@ -40,11 +40,6 @@ class RelationshipInclusionTest extends AbstractTestCase
         $this->markTestIncomplete();
     }
 
-    public function test_to_one_relationships_can_have_custom_preloaders()
-    {
-        $this->markTestIncomplete();
-    }
-
     public function test_to_one_relationships_can_be_not_loadable()
     {
         $this->markTestIncomplete();