Docs: Improve `@since` notes for some `WP_Filesystem_*` methods:

* `WP_Filesystem_FTPext::exists()`
* `WP_Filesystem_FTPext::size()`
* `WP_Filesystem_ftpsockets::exists()`

The `::exists()` methods were previously using the FTP `NLST` command, which works for directories, but is not intended to be applied to a file. This only worked most of the time due to many FTP servers being permissive and allowing to execute `NLST` on files, which cannot be guaranteed and appears to not be the case in newer versions of Pure-FTPd (1.0.48 or later).

With a recent change in [53860], both methods were updated for compatibility with RFC 959:

* Both methods check if the path is a directory that can be changed into (and therefore exists).
* `WP_Filesystem_FTPext` uses `ftp_rawlist()` (FTP `LIST` command) to check for file existence.
* `WP_Filesystem_ftpsockets` uses file size to check for file existence.

Reference: [https://www.ietf.org/rfc/rfc959.txt RFC 959: File Transfer Protocol (FTP)]

Follow-up to [6779], [11821], [25274], [33648], [34733], [35944], [35946], [53860].

See #51170.
Built from https://develop.svn.wordpress.org/trunk@53862


git-svn-id: http://core.svn.wordpress.org/trunk@53421 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/class-wp-filesystem-ftpext.php

@@ -412,8 +412,8 @@ class WP_Filesystem_FTPext extends WP_Filesystem_Base {
 	 * Checks if a file or directory exists.
 	 *
 	 * @since 2.5.0
-	 * @since 6.1.0 Rewrite using ftp_rawlist, uses 'LIST' on FTP server
-	 *              takes file path or directory path as parameter.
+	 * @since 6.1.0 Uses WP_Filesystem_FTPext::is_dir() to check for directory existence
+	 *              and ftp_rawlist() to check for file existence.
 	 *
 	 * @param string $file Path to file or directory.
 	 * @return bool Whether $file exists or not.
@@ -510,7 +510,8 @@ class WP_Filesystem_FTPext extends WP_Filesystem_Base {
 	 * Gets the file size (in bytes).
 	 *
 	 * @since 2.5.0
-	 * @since 6.1.0 Update for proper return values.
+	 * @since 6.1.0 Corrected the return value: while WP_Filesystem_Base::size()
+	 *              is documented to return false on failure, ftp_size() returns -1.
 	 *
 	 * @param string $file Path to file.
 	 * @return int Size of the file in bytes on success, -1 on failure.

wp-admin/includes/class-wp-filesystem-ftpsockets.php

@@ -414,7 +414,8 @@ class WP_Filesystem_ftpsockets extends WP_Filesystem_Base {
 	 * Checks if a file or directory exists.
 	 *
 	 * @since 2.5.0
-	 * @since 6.1.0 Rewrite using file size.
+	 * @since 6.1.0 Uses WP_Filesystem_ftpsockets::is_dir() to check for directory existence
+	 *              and file size to check for file existence.
 	 *
 	 * @param string $file Path to file or directory.
 	 * @return bool Whether $file exists or not.

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.1-alpha-53861';
+$wp_version = '6.1-alpha-53862';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.