Add find sole query builder method (#54667)

Author: zepfietje

src/Illuminate/Database/Eloquent/Builder.php

@@ -477,6 +477,21 @@ public function find($id, $columns = ['*'])
         return $this->whereKey($id)->first($columns);
     }
 
+    /**
+     * Find a sole model by its primary key.
+     *
+     * @param  mixed  $id
+     * @param  array|string  $columns
+     * @return TModel
+     *
+     * @throws \Illuminate\Database\Eloquent\ModelNotFoundException<TModel>
+     * @throws \Illuminate\Database\MultipleRecordsFoundException
+     */
+    public function findSole($id, $columns = ['*'])
+    {
+        return $this->whereKey($id)->sole($columns);
+    }
+
     /**
      * Find multiple models by their primary keys.
      *

src/Illuminate/Database/Eloquent/Relations/BelongsToMany.php

@@ -696,6 +696,23 @@ public function find($id, $columns = ['*'])
         )->first($columns);
     }
 
+    /**
+     * Find a sole related model by its primary key.
+     *
+     * @param  mixed  $id
+     * @param  array  $columns
+     * @return TRelatedModel
+     *
+     * @throws \Illuminate\Database\Eloquent\ModelNotFoundException<TRelatedModel>
+     * @throws \Illuminate\Database\MultipleRecordsFoundException
+     */
+    public function findSole($id, $columns = ['*'])
+    {
+        return $this->where(
+            $this->getRelated()->getQualifiedKeyName(), '=', $this->parseId($id)
+        )->sole($columns);
+    }
+
     /**
      * Find multiple related models by their primary keys.
      *

src/Illuminate/Database/Eloquent/Relations/HasOneOrManyThrough.php

@@ -342,6 +342,23 @@ public function find($id, $columns = ['*'])
         )->first($columns);
     }
 
+    /**
+     * Find a sole related model by its primary key.
+     *
+     * @param  mixed  $id
+     * @param  array  $columns
+     * @return TRelatedModel
+     *
+     * @throws \Illuminate\Database\Eloquent\ModelNotFoundException<TRelatedModel>
+     * @throws \Illuminate\Database\MultipleRecordsFoundException
+     */
+    public function findSole($id, $columns = ['*'])
+    {
+        return $this->where(
+            $this->getRelated()->getQualifiedKeyName(), '=', $id
+        )->sole($columns);
+    }
+
     /**
      * Find multiple related models by their primary keys.
      *