Auto-discover nested policies following conventional, parallel hierarchy

src/Illuminate/Auth/Access/Gate.php

@@ -703,6 +703,9 @@ protected function guessPolicyName($class)
             $classDirname = implode('\\', array_slice($classDirnameSegments, 0, $index));
 
             return $classDirname.'\\Policies\\'.class_basename($class).'Policy';
+        })->when(str_contains($classDirname, '\\Models\\'), function ($collection) use ($class, $classDirname) {
+            return $collection->concat([str_replace('\\Models\\', '\\Policies\\', $classDirname).'\\'.class_basename($class).'Policy'])
+                ->concat([str_replace('\\Models\\', '\\Models\\Policies\\', $classDirname).'\\'.class_basename($class).'Policy']);
         })->reverse()->values()->first(function ($class) {
             return class_exists($class);
         }) ?: [$classDirname.'\\Policies\\'.class_basename($class).'Policy']);

tests/Integration/Auth/Fixtures/Models/Nested/SubTestUser.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Illuminate\Tests\Integration\Auth\Fixtures\Models\Nested;
+
+use Illuminate\Foundation\Auth\User as Authenticatable;
+
+class SubTestUser extends Authenticatable
+{
+    public $table = 'users';
+    public $timestamps = false;
+
+    /**
+     * The attributes that aren't mass assignable.
+     *
+     * @var string[]
+     */
+    protected $guarded = [];
+
+    /**
+     * The attributes that should be hidden for arrays.
+     *
+     * @var string[]
+     */
+    protected $hidden = [
+        'password', 'remember_token',
+    ];
+}

tests/Integration/Auth/Fixtures/Models/Nested/TopTestUser.php

@@ -0,0 +1,27 @@
+<?php
+
+namespace Illuminate\Tests\Integration\Auth\Fixtures\Models\Nested;
+
+use Illuminate\Foundation\Auth\User as Authenticatable;
+
+class TopTestUser extends Authenticatable
+{
+    public $table = 'users';
+    public $timestamps = false;
+
+    /**
+     * The attributes that aren't mass assignable.
+     *
+     * @var string[]
+     */
+    protected $guarded = [];
+
+    /**
+     * The attributes that should be hidden for arrays.
+     *
+     * @var string[]
+     */
+    protected $hidden = [
+        'password', 'remember_token',
+    ];
+}

tests/Integration/Auth/Fixtures/Models/Policies/Nested/SubTestUserPolicy.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace Illuminate\Tests\Integration\Auth\Fixtures\Models\Policies\Nested;
+
+class SubTestUserPolicy
+{
+    //
+}

tests/Integration/Auth/Fixtures/Policies/Nested/TopTestUserPolicy.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace Illuminate\Tests\Integration\Auth\Fixtures\Policies\Nested;
+
+class TopTestUserPolicy
+{
+    //
+}

tests/Integration/Auth/GatePolicyResolutionTest.php

@@ -6,7 +6,9 @@
 use Illuminate\Support\Facades\Event;
 use Illuminate\Support\Facades\Gate;
 use Illuminate\Tests\Integration\Auth\Fixtures\AuthenticationTestUser;
+use Illuminate\Tests\Integration\Auth\Fixtures\Models\Policies\Nested\SubTestUserPolicy;
 use Illuminate\Tests\Integration\Auth\Fixtures\Policies\AuthenticationTestUserPolicy;
+use Illuminate\Tests\Integration\Auth\Fixtures\Policies\Nested\TopTestUserPolicy;
 use Orchestra\Testbench\TestCase;
 
 class GatePolicyResolutionTest extends TestCase
@@ -37,6 +39,19 @@ public function testPolicyCanBeGuessedUsingClassConventions()
         );
     }
 
+    public function testPolicyCanBeGuessedForParallelClassHierarchies()
+    {
+        $this->assertInstanceOf(
+            TopTestUserPolicy::class,
+            Gate::getPolicyFor(Fixtures\Models\Nested\TopTestUser::class)
+        );
+
+        $this->assertInstanceOf(
+            SubTestUserPolicy::class,
+            Gate::getPolicyFor(Fixtures\Models\Nested\SubTestUser::class)
+        );
+    }
+
     public function testPolicyCanBeGuessedUsingCallback()
     {
         Gate::guessPolicyNamesUsing(function () {