Added comment

Author: Nyholm

CHANGELOG.md

@@ -6,7 +6,7 @@
 
 - RetryPlugin: Renamed the configuration options for the exception retry callback from `decider` to `exception_decider`
   and `delay` to `exception_delay`. The old names still work but are deprecated.
-- AddPathPlugin does not add prefix if the prefix already is defined. 
+- AddPathPlugin: Do not add the prefix if the URL already has the same prefix.
 
 
 ## 1.8.2 - 2018-12-14

src/Plugin/AddPathPlugin.php

@@ -18,13 +18,6 @@ final class AddPathPlugin implements Plugin
      */
     private $uri;
 
-    /**
-     * Stores identifiers of the already altered requests.
-     *
-     * @var array
-     */
-    private $alteredRequests = [];
-
     /**
      * @param UriInterface $uri
      */
@@ -42,6 +35,21 @@ public function __construct(UriInterface $uri)
     }
 
     /**
+     * Adds a prefix in the beginning of the URL's path. We will not add the prefix
+     * if it already exists. This will of course not cover all the edge cases. For
+     * example when you have a valid URL like `https://example.com/api/api/foo` and
+     * you are using the prefix "/api".
+     *
+     * Some of the other edge cases are:
+     *  - request objects can be reused,
+     *  - plugin chains could be restarted
+     *  - multiple AddPathPlugins may exist in one chain.
+     *
+     * If one would like to cover all these scenarios one would have to add a custom
+     * header to the request to indicate it has been rewritten by the plugin. This
+     * implementation does not aim for pleasing all edge cases rather to be great
+     * value for the 95% other use cases.
+     *
      * {@inheritdoc}
      */
     public function handleRequest(RequestInterface $request, callable $next, callable $first)