bug#48598: 28.0.50; buffer-naming collisions involving bouncers in ERC

[J.P.]

Update #6.

With the one-year anniversary of this bug finally upon us, it felt only
fitting to furnish yet another (hopefully final) update. I say final
because as long as we're willing to accept the proposed behavior as
mostly correct, a move to iterating on trunk seems (IMO) warranted, if
only to avoid further alienating those who've been patiently awaiting
these and other, dependent changes.

(If you'll recall, this was the only ERC bug to occupy #emacs topic real
estate for weeks on end during all of 27.1.)

To review, this bug set introduces the following items for export:

   5 functions
   6 options
   2 other           (everything else is internal)


 * lisp/erc/erc.el:

   function: `erc-auth-source-search'
             Default value of all `erc-auth-source-*-function' options.
             Queries `auth-source-search' with params derived from
             protocol context, connection properties, and caller
             overrides.

   function: `erc-compute-user'
             Determines first positional arg of IRC "USER" command to
             send when not otherwise supplied. Could be internal (IMO);
             exported for consistency with "compute-foo" convention.

     option: `erc-auth-source-server-function',
             `erc-auth-source-join-function'
             Functions for querying auth-source in various contexts. See
             also `erc-auth-source-services-function' below.

     option: `erc-prompt-hidden' and `erc-unhide-query-prompt'
             See bug#54826: Prevent duplicate prompts when reconnecting
             in ERC.

     option: `erc-reconnect-display'
             See bug#51753: ERC switches to channel buffer on reconnect.


 * lisp/erc/erc-backend.el:

   variable: `erc-session-username'
             See bug#54824: Add 'user' parameter to ERC entry-point
             commands.


 * lisp/erc/erc-networks.el:

   function: `erc-networks-shrink-ids-and-buffer-names' and
             `erc-networks-rename-surviving-target-buffer'
             These undo certain uniquifying effects when disambiguation
             is no longer relevant. Would be internal if not for being
             default members of various buffer-killing hooks.

   function: `erc-networks-on-MOTD-end'
             Performs primary network-context related setup right before
             logical connection formally established.

      other: `erc-obsolete-var'
             Generic context rewriter.


 * lisp/erc/erc-services.el:

     option: `erc-auth-source-services-function'
             See `erc-auth-source-server-function' above. Should perhaps
             be renamed `erc-auth-source-nickserv-function' to avoid
             confusion with the latter.


For major behavioral changes and deprecations, please see the updates to
etc/ERC-NEWS in the last patch below. Some of the language is merely
speculative and bears further discussion (in particular, the thing about
a new naming convention for edge functionality). In that same patch,
you'll also find updates to the texinfo doc describing (not so much
changes to but) new behavior for existing options and commands. Other,
less consequential changes of more or less minor disruptive potential
are noted in the commit logs themselves.

And with that, people, I once again implore you:

  see something, say something!

Thanks,
J.P.

0001-Rework-mutual-dependency-between-erc-and-erc-backend.patch
Description: Text Data

0002-Initialize-erc-server-filter-data-in-erc-backend.patch
Description: Text Data

0003-Accept-user-keyword-arg-in-ERC-entry-point-commands.patch
Description: Text Data

0004-Add-some-ERC-test-helpers.patch
Description: Text Data

0005-SQUASH-ME-Remove-duplicate-ERC-prompt-on-reconnect.patch
Description: Text Data

0006-Customize-displaying-of-ERC-buffers-on-reconnect.patch
Description: Text Data

0007-Allow-exemption-from-flood-penalty-in-erc-backend.patch
Description: Text Data

0008-Don-t-set-erc-server-announced-name-unless-known.patch
Description: Text Data

0009-Require-erc-networks-in-erc.el.patch
Description: Text Data

0010-Update-ISUPPORT-handling-in-ERC.patch
Description: Text Data

0011-Recognize-ASCII-and-strict-CASEMAPPINGs-in-ERC.patch
Description: Text Data

0012-Make-ERC-respect-spaces-in-server-passwords.patch
Description: Text Data

0013-Add-helper-to-determine-local-channels-in-ERC.patch
Description: Text Data

0014-Add-eventual-replacement-for-erc-default-recipients.patch
Description: Text Data

0015-Discourage-ill-defined-use-of-buffer-targets-in-ERC.patch
Description: Text Data

0016-Add-ERC-test-server-and-related-resources.patch
Description: Text Data

0017-Address-long-standing-ERC-buffer-naming-issues.patch
Description: Text Data

0018-SQUASH-ME-Add-user-oriented-test-scenarios-for-ERC.patch
Description: Text Data

0019-Register-erc-kill-buffer-function-locally.patch
Description: Text Data

0020-Don-t-call-erc-auto-query-twice-on-PRIVMSG.patch
Description: Text Data

0021-SQUASH-ME-Add-ERC-scenarios-for-identity-aware-msg-h.patch
Description: Text Data

0022-Favor-network-identities-in-erc-join.patch
Description: Text Data

0023-SQUASH-ME-Add-ERC-test-scenarios-for-identity-aware-.patch
Description: Text Data

0024-Standardize-auth-source-queries-in-ERC.patch
Description: Text Data

0025-SQUASH-ME-Add-ERC-test-scenarios-involving-auth-sour.patch
Description: Text Data

0026-SQUASH-ME-Add-ERC-test-scenarios-for-erc-cmd-JOIN.patch
Description: Text Data

0027-Update-ERC-s-Info-doc-with-network-ID-related-change.patch
Description: Text Data