From 4f0c8ef6658089303147f7078ffaed6986aae1b7 Mon Sep 17 00:00:00 2001
From: hellofromTonya <hellofromTonya@git.wordpress.org>
Date: Tue, 7 Dec 2021 16:51:03 +0000
Subject: [PATCH] Upgrade/Install: Fix moving plugins folder in `WP_Upgrader::
 move_to_temp_backup_dir()`.

[51815] introduced the creation of a temporary backup of plugins before updating.

The `move()` (and later, `move_dir()`) call) uses a `$src` parameter.
For Hello Dolly, this is `<path>/wp-contents/plugins/.` (note the period at the end).

For users on Linux and Mac, this doesn't appear to cause any problems.
However, on Windows, the move causes the plugins folder to be moved which then causes a failure when attempting to call `mkdir()`.

This commit skips any plugin whose slug is `'.'` as this slug results in the `$src` value ending in a period.

Follow-up to [51815].

Props costdev, boniu91, hellofromTonya.
Fixes #54543.
Built from https://develop.svn.wordpress.org/trunk@52337


git-svn-id: http://core.svn.wordpress.org/trunk@51929 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-admin/includes/class-wp-upgrader.php | 11 +++++++++++
 wp-includes/version.php                 |  2 +-
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/wp-admin/includes/class-wp-upgrader.php b/wp-admin/includes/class-wp-upgrader.php
index 396672585d..d17a7a7de6 100644
--- a/wp-admin/includes/class-wp-upgrader.php
+++ b/wp-admin/includes/class-wp-upgrader.php
@@ -1025,6 +1025,17 @@ class WP_Upgrader {
 			return false;
 		}
 
+		/**
+		 * Skip any plugin that has "." as its slug.
+		 * A slug of "." will result in a `$src` value ending in a period.
+		 *
+		 * On Windows, this will cause the 'plugins' folder to be moved,
+		 * and will cause a failure when attempting to call `mkdir()`.
+		 */
+		if ( '.' === $args['slug'] ) {
+			return false;
+		}
+
 		$dest_dir = $wp_filesystem->wp_content_dir() . 'upgrade/temp-backup/';
 		// Create the temp-backup directory if it doesn't exist.
 		if ( (
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 5dceb620a3..edf7a35bf8 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.9-beta1-52336';
+$wp_version = '5.9-beta1-52337';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.