Creating and applying a patch

I need to generate a patch and then apply automatically to my Drupal installation.

Current path to the file: web/core/modules/views/src/Plugin/views/argument/

Orignal filename: ArgumentPluginBase.php

Adjusted filename: ArgumentPluginBase-adjusted.php

Create a Patch

A patch is used to create or override changes in another file.  The command to create a patch is:

diff -u {original filename} {changed filename} > {patchfile}.patch

diff -u web/core/modules/views/src/Plugin/views/argument/ArgumentPluginBase.php web/core/modules/views/src/Plugin/views/argument/ArgumentPluginBase-adjusted.php > patches/argument-plugin-base-operator.patch

Response:

--- web/core/modules/views/src/Plugin/views/argument/ArgumentPluginBase.php	2023-09-08 01:19:51
+++ web/core/modules/views/src/Plugin/views/argument/ArgumentPluginBase-adjusted.php	2023-09-18 21:52:15
@@ -108,7 +108,7 @@
   /**
    * The operator used for the query: or|and.
    */
-  public string $operator;
+  public ?string $operator;
 
   /**
    * The title set by argument validation.