Update IRC-related references to point to Libera.Chat

Per GNU and FSF's announcements [0, 1] of moving official IRC channels
to the Libera.Chat IRC network, as well as several Emacs-related
channels following suit [2], update IRC-related references to reflect
the migration.

[0]: https://lists.gnu.org/archive/html/info-gnu/2021-06/msg00005.html
[1]: https://lists.gnu.org/archive/html/info-gnu/2021-06/msg00007.html
[2]: https://lists.gnu.org/archive/html/info-gnu-emacs/2021-06/msg00000.html

4 files changed, 37 insertions, 17 deletions

diff --git a/lisp/erc/erc-backend.el b/lisp/erc/erc-backend.el
index dcda9044a55..2c2f62e76ed 100644
--- a/lisp/erc/erc-backend.el
+++ b/lisp/erc/erc-backend.el
@@ -1793,7 +1793,7 @@ See `erc-display-server-message'." nil
      's324 ?c channel ?m modes)))
 
 (define-erc-response-handler (328)
-  "Channel URL (on freenode network)." nil
+  "Channel URL." nil
   (let ((channel (cadr (erc-response.command-args parsed)))
         (url (erc-response.contents parsed)))
     (erc-display-message parsed 'notice (erc-get-buffer channel proc)
diff --git a/lisp/erc/erc-networks.el b/lisp/erc/erc-networks.el
index 4a566096cb1..ac32b294d3c 100644
--- a/lisp/erc/erc-networks.el
+++ b/lisp/erc/erc-networks.el
@@ -290,6 +290,13 @@
   ("LagNet: Random server" LagNet "irc.lagnet.org.za" 6667)
   ("LagNet: AF, ZA, Cape Town" LagNet "reaper.lagnet.org.za" 6667)
   ("LagNet: AF, ZA, Johannesburg" LagNet "mystery.lagnet.org.za" 6667)
+  ("Libera.Chat: Random server" Libera.Chat "irc.libera.chat" 6667)
+  ("Libera.Chat: Random Europe server" Libera.Chat "irc.eu.libera.chat" 6667)
+  ("Libera.Chat: Random US & Canada server" Libera.Chat "irc.us.libera.chat" 6667)
+  ("Libera.Chat: Random Australia & New Zealand server" Libera.Chat "irc.au.libera.chat" 6667)
+  ("Libera.Chat: Random East Asia server" Libera.Chat "irc.ea.libera.chat" 6667)
+  ("Libera.Chat: IPv4 only server" Libera.Chat "irc.ipv4.libera.chat" 6667)
+  ("Libera.Chat: IPv6 only server" Libera.Chat "irc.ipv6.libera.chat" 6667)
   ("Librenet: Random server" Librenet "irc.librenet.net" 6667)
   ("LinkNet: Random server" LinkNet "irc.link-net.org" ((6667 6669)))
   ("LinuxChix: Random server" LinuxChix "irc.linuxchix.org" 6667)
@@ -595,6 +602,7 @@ PORTS is either a number, a list of numbers, or a list of port ranges."
     (Krono "krono.net")
     (Krushnet "krushnet.org")
     (LagNet "lagnet.org.za")
+    (Libera.Chat "libera.chat")
     (Librenet "librenet.net")
     (LinkNet "link-net.org")
     (LinuxChix "cats\\.meow\\.at\\|linuxchix\\.org")
@@ -836,8 +844,8 @@ As an example:
 ;; think it is worth the effort.
 
 (defvar erc-settings
-  '((pals freenode ("kensanata" "shapr" "anti\\(fuchs\\|gone\\)"))
-    (format-nick-function (freenode "#emacs") erc-format-@nick))
+  '((pals Libera.Chat ("kensanata" "shapr" "anti\\(fuchs\\|gone\\)"))
+    (format-nick-function (Libera.Chat "#emacs") erc-format-@nick))
   "Experimental: Alist of configuration options.
 The format is (VARNAME SCOPE VALUE) where
 VARNAME is a symbol identifying the configuration option,
@@ -866,7 +874,7 @@ VALUE is the options value.")
                      items nil)))))
     val))
 
-(erc-get 'pals 'freenode)
+(erc-get 'pals 'Libera.Chat)
 
 (provide 'erc-networks)
 
diff --git a/lisp/erc/erc-services.el b/lisp/erc/erc-services.el
index 4f9b0b199f9..f04da183c64 100644
--- a/lisp/erc/erc-services.el
+++ b/lisp/erc/erc-services.el
@@ -30,10 +30,10 @@
 ;; are made to test if NickServ is the real NickServ for a given network or
 ;; server.
 
-;; As a default, ERC has the data for the official nickname services on
-;; the networks Austnet, BrasNET, Dalnet, freenode, GalaxyNet, GRnet,
-;; and Slashnet.  You can add more by using M-x customize-variable RET
-;; erc-nickserv-alist.
+;; As a default, ERC has the data for the official nickname services
+;; on the networks Austnet, BrasNET, Dalnet, freenode, GalaxyNet,
+;; GRnet, Libera.Chat, and Slashnet.  You can add more by using
+;; M-x customize-variable RET erc-nickserv-alist.
 
 ;; Usage:
 ;;
@@ -43,9 +43,10 @@
 ;; (erc-services-mode 1)
 ;;
 ;; Add your nickname and NickServ password to `erc-nickserv-passwords'.
-;; Using the freenode network as an example:
+;; Using the Libera.Chat network as an example:
 ;;
-;; (setq erc-nickserv-passwords '((freenode (("nickname" "password")))))
+;; (setq erc-nickserv-passwords
+;;       '((Libera.Chat (("nickname" "password")))))
 ;;
 ;; The default automatic identification mode is autodetection of NickServ
 ;; identify requests.  Set the variable `erc-nickserv-identify-mode' if
@@ -173,8 +174,8 @@ You can also use \\[erc-nickserv-identify-mode] to change modes."
 
 Example of use:
   (setq erc-nickserv-passwords
-        \\='((freenode ((\"nick-one\" . \"password\")
-                     (\"nick-two\" . \"password\")))
+        \\='((Libera.Chat ((\"nick-one\" . \"password\")
+                        (\"nick-two\" . \"password\")))
           (DALnet ((\"nick\" . \"password\")))))"
   :group 'erc-services
   :type '(repeat
@@ -190,6 +191,7 @@ Example of use:
                         (const GalaxyNet)
                         (const GRnet)
                         (const iip)
+                        (const Libera.Chat)
                         (const OFTC)
                         (const QuakeNet)
                         (const Rizon)
@@ -257,6 +259,15 @@ Example of use:
      "type\\s-/squery\\s-Trent\\s-identify\\s-<password>"
      "Trent@anon.iip"
      "IDENTIFY" nil "SQUERY" nil)
+    (Libera.Chat
+     "NickServ!NickServ@services.libera.chat"
+     ;; Libera.Chat also accepts a password at login, see the `erc'
+     ;; :password argument.
+     "This\\s-nickname\\s-is\\s-registered.\\s-Please\\s-choose"
+     "NickServ"
+     "IDENTIFY" nil nil
+     ;; See also the 901 response code message.
+     "You\\s-are\\s-now\\s-identified\\s-for\\s-")
     (OFTC
      "NickServ!services@services.oftc.net"
      ;; OFTC's NickServ doesn't ask you to identify anymore.
diff --git a/lisp/erc/erc.el b/lisp/erc/erc.el
index 1e055a6c521..2bd58ba9379 100644
--- a/lisp/erc/erc.el
+++ b/lisp/erc/erc.el
@@ -255,7 +255,7 @@ A typical value would be \(\"JOIN\" \"PART\" \"QUIT\")."
 
 (defcustom erc-network-hide-list nil
   "A list of IRC networks to hide message types from.
-A typical value would be \((\"freenode\" \"MODE\")
+A typical value would be \((\"Libera.Chat\" \"MODE\")
   \(\"OFTC\" \"JOIN\" \"QUIT\"))."
   :version "25.1"
   :group 'erc-ignore
@@ -1499,7 +1499,7 @@ Defaults to the server buffer."
 
 ;; activation
 
-(defconst erc-default-server "irc.freenode.net"
+(defconst erc-default-server "irc.libera.chat"
   "IRC server to use if it cannot be detected otherwise.")
 
 (defconst erc-default-port 6667
@@ -2229,7 +2229,7 @@ Non-interactively, it takes the keyword arguments
 
 That is, if called with
 
-   (erc :server \"irc.freenode.net\" :full-name \"Harry S Truman\")
+   (erc :server \"irc.libera.chat\" :full-name \"J. Random Hacker\")
 
 then the server and full-name will be set to those values, whereas
 `erc-compute-port', `erc-compute-nick' and `erc-compute-full-name' will
@@ -3355,8 +3355,9 @@ to send.
 
 If only one word is given, display the mode of that target.
 
-A list of valid mode strings for Freenode may be found at
-URL `http://freenode.net/using_the_network.shtml'."
+A list of valid mode strings for Libera.Chat may be found at
+`https://libera.chat/guides/channelmodes' and
+`https://libera.chat/guides/usermodes'."
   (cond
    ((string-match "^\\s-\\(.*\\)$" line)
     (let ((s (match-string 1 line)))