[9.x] Add Conditionable support for callback conditions (#37667)

* Add `Conditionable` support for callback conditions

* Update DocBlocks in `Enumerable` to match `Conditionable`

* Update uses

* Add to collection higher order proxy

Author: JosephSilber

Collection.php

@@ -1069,7 +1069,7 @@ public function sole($key = null, $operator = null, $value = null)
             ? $this->operatorForWhere(...func_get_args())
             : $key;
 
-        $items = $this->when($filter)->filter($filter);
+        $items = $this->unless($filter == null)->filter($filter);
 
         if ($items->isEmpty()) {
             throw new ItemNotFoundException;

Enumerable.php

@@ -268,7 +268,7 @@ public function except($keys);
     public function filter(callable $callback = null);
 
     /**
-     * Apply the callback if the value is truthy.
+     * Apply the callback if the given "value" is (or resolves to) truthy.
      *
      * @param  bool  $value
      * @param  callable|null  $callback
@@ -296,7 +296,7 @@ public function whenEmpty(callable $callback, callable $default = null);
     public function whenNotEmpty(callable $callback, callable $default = null);
 
     /**
-     * Apply the callback if the value is falsy.
+     * Apply the callback if the given "value" is (or resolves to) truthy.
      *
      * @param  bool  $value
      * @param  callable  $callback

LazyCollection.php

@@ -1028,7 +1028,7 @@ public function sole($key = null, $operator = null, $value = null)
             : $key;
 
         return $this
-            ->when($filter)
+            ->unless($filter == null)
             ->filter($filter)
             ->take(2)
             ->collect()

Traits/EnumeratesValues.php

@@ -31,16 +31,18 @@
  * @property-read HigherOrderCollectionProxy $min
  * @property-read HigherOrderCollectionProxy $partition
  * @property-read HigherOrderCollectionProxy $reject
+ * @property-read HigherOrderCollectionProxy $skipUntil
+ * @property-read HigherOrderCollectionProxy $skipWhile
  * @property-read HigherOrderCollectionProxy $some
  * @property-read HigherOrderCollectionProxy $sortBy
  * @property-read HigherOrderCollectionProxy $sortByDesc
- * @property-read HigherOrderCollectionProxy $skipUntil
- * @property-read HigherOrderCollectionProxy $skipWhile
  * @property-read HigherOrderCollectionProxy $sum
  * @property-read HigherOrderCollectionProxy $takeUntil
  * @property-read HigherOrderCollectionProxy $takeWhile
  * @property-read HigherOrderCollectionProxy $unique
+ * @property-read HigherOrderCollectionProxy $unless
  * @property-read HigherOrderCollectionProxy $until
+ * @property-read HigherOrderCollectionProxy $when
  */
 trait EnumeratesValues
 {
@@ -76,7 +78,9 @@ trait EnumeratesValues
         'takeUntil',
         'takeWhile',
         'unique',
+        'unless',
         'until',
+        'when',
     ];
 
     /**
@@ -138,7 +142,7 @@ public static function times($number, callable $callback = null)
         }
 
         return static::range(1, $number)
-            ->when($callback)
+            ->unless($callback == null)
             ->map($callback);
     }