* etc/ERC-NEWS: Mention that certain aberrant response handlers now
return nil.
* lisp/erc/erc-backend.el (define-erc-response-handler): Mention that
body should explicitly return nil.
(erc-server-PART)
(erc-server-PING): Return nil.
* lisp/erc/erc-sasl.el (erc-sasl--destroy): Return nil.
* lisp/erc/erc.el (erc-display-message): Mention in doc string that
the return value is undefined.
(erc-kill-channel-hook): Fix package-version.
* test/lisp/erc/erc-networks-tests.el (erc-networks--set-name): Ensure
`erc--route-insertion' returns nil because this influences whether
response-handler hooks continue running.
* test/lisp/erc/erc-sasl-tests.el
(erc-sasl-create-client-ecdsa): Fix regression that made test
unusable, although it's still relatively useless and therefore skipped
by default.
* test/lisp/erc/erc-services-tests.el
(erc-services-tests--auth-source-standard)
(erc-services-tests--auth-source-announced): Clarify annotations.
* test/lisp/erc/erc-tests.el (erc-message): Don't return non-nil in
mocked `erc-display-message'.
(erc-send-modify-hook): Shadow `erc-send-modify-hook' because
`erc-stamp--date-mode' modifies it locally.
* doc/misc/erc.texi: Revise descriptions in SASL chapter to reflect
simplified auth-source options.
* lisp/erc/erc-sasl.el (erc-sasl-password,
erc-sasl-auth-source-function): Revise doc strings.
(erc-sasl-auth-source-password-as-host): New function to serve as
more useful choice for option `erc-sasl-auth-source-function'.
(erc-sasl--read-password): Promote auth-source to pole position, above
an explicit string and `:password'.
* test/lisp/erc/erc-sasl-tests.el (erc-sasl--read-password--basic):
Massage tests to conform to simplified `erc-sasl-password'
API. (Bug#29108.)
* lisp/erc/erc-sasl.el (erc-sasl--read-password): Consult cached
options instead of `erc-sasl-auth-source-function'.
(erc-sasl--init): Add `erc-sasl-auth-source-function' to
`erc-sasl--options'.
* test/lisp/erc/erc-sasl-tests.el (erc-sasl--read-password--basic,
erc-sasl--read-password--auth-source): Look for original value of
`erc-sasl-auth-source-function' in `erc-sasl--options' under the
`authfn' key.
* doc/misc/erc.texi: Add SASL section in Advanced Usage chapter to
document the new SASL module.
* etc/ERC-NEWS: Mention addition of erc-sasl module for SASL support.
* lisp/erc/erc-compat.el
(erc-compat--29-sasl-scram-construct-gs2-header,
erc-compat--29-sasl-scram-client-first-message,
erc-compat--29-sasl-scram--client-final-message): Fix encoding bug and
add minimal authorization support with copies of SASL functions
introduced in Emacs 29.
* lisp/erc/erc.el (erc-modules): Add `sasl'.
* lisp/erc/erc-sasl.el: New file (bug#29108).
* test/lisp/erc/erc-sasl-tests.el: New file.
* test/lisp/erc/erc-scenarios-sasl.el: New file.
* test/lisp/erc/resources/sasl/plain-failed.eld: New file.
* test/lisp/erc/resources/sasl/plain.eld: New file.
* test/lisp/erc/resources/sasl/scram-sha-1.eld: New file.
* test/lisp/erc/resources/sasl/scram-sha-256.eld: New file.
* test/lisp/erc/resources/sasl/external.eld: New file.
