[8.x] Add more readable missing method to Session\Store (#36937)

* Add missing helper for session

* Update Store.php

Co-authored-by: Taylor Otwell <taylor@laravel.com>

src/Illuminate/Session/Store.php

@@ -193,6 +193,17 @@ public function exists($key)
         });
     }
 
+    /**
+     * Determine if the given key is missing from the session data.
+     *
+     * @param  string|array  $key
+     * @return bool
+     */
+    public function missing($key)
+    {
+        return ! $this->exists($key);
+    }
+
     /**
      * Checks if a key is present and not null.
      *

tests/Session/SessionStoreTest.php

@@ -452,6 +452,22 @@ public function testKeyExists()
         $this->assertFalse($session->exists(['hulk.two']));
     }
 
+    public function testKeyMissing()
+    {
+        $session = $this->getSession();
+        $session->put('foo', 'bar');
+        $this->assertFalse($session->missing('foo'));
+        $session->put('baz', null);
+        $session->put('hulk', ['one' => true]);
+        $this->assertFalse($session->has('baz'));
+        $this->assertFalse($session->missing('baz'));
+        $this->assertTrue($session->missing('bogus'));
+        $this->assertFalse($session->missing(['foo', 'baz']));
+        $this->assertTrue($session->missing(['foo', 'baz', 'bogus']));
+        $this->assertFalse($session->missing(['hulk.one']));
+        $this->assertTrue($session->missing(['hulk.two']));
+    }
+
     public function testRememberMethodCallsPutAndReturnsDefault()
     {
         $session = $this->getSession();