The new opaque type replaces the previous use of vectors for obarrays.
`obarray-make` now returns objects of this type.  Functions that take
obarrays continue to accept vectors for compatibility, now just using
their first slot to store an actual obarray object.

obarray-size and obarray-default-size now obsolete.

* lisp/obarray.el (obarray-default-size, obarray-size):
Declare obsolete.
(obarray-make, obarrayp, obarray-clear): Remove from here.
* src/fns.c (reduce_emacs_uint_to_hash_hash): Remove from here.
* src/lisp.h (struct Lisp_Obarray, OBARRAYP, XOBARRAY, CHECK_OBARRAY)
(make_lisp_obarray, obarray_size, obarray_bucket, check_obarray)
(obarray_iter_t, make_obarray_iter, obarray_iter_at_end)
(obarray_iter_step, obarray_iter_symbol, DOOBARRAY, knuth_hash): New.
(reduce_emacs_uint_to_hash_hash): Moved here.
* src/lread.c (check_obarray): Renamed and reworked as...
(checked_obarray_slow): ...this.
(intern_sym, Funintern, oblookup, map_obarray)
(Finternal__obarray_buckets): Adapt to new type.
(obarray_index, allocate_obarray, make_obarray, grow_obarray)
(obarray_default_bits, Fobarray_make, Fobarrayp, Fobarray_clear): New.
* etc/emacs_lldb.py (Lisp_Object):
* lisp/emacs-lisp/cl-macs.el (`(,type . ,pred)):
* lisp/emacs-lisp/cl-preloaded.el (cl--typeof-types):
* lisp/emacs-lisp/comp-common.el (comp-known-type-specifiers):
* lisp/emacs-lisp/comp.el (comp-known-predicates):
* src/alloc.c (cleanup_vector, process_mark_stack):
* src/data.c (Ftype_of, syms_of_data):
* src/minibuf.c (Ftry_completion, Fall_completions, Ftest_completion):
* src/pdumper.c (dump_obarray_buckets, dump_obarray, dump_vectorlike):
* src/print.c (print_vectorlike_unreadable):
* test/lisp/abbrev-tests.el (abbrev-make-abbrev-table-test):
* test/lisp/obarray-tests.el (obarrayp-test)
(obarrayp-unchecked-content-test, obarray-make-default-test)
(obarray-make-with-size-test):
Adapt to new type.

This way, we can use a new type.

* lisp/cedet/semantic/lex-spp.el (semantic-lex-spp-dynamic-map)
(semantic-lex-spp-dynamic-map-stack, semantic-lex-make-spp-table):
* lisp/cedet/semantic/lex.el (semantic-lex-make-keyword-table)
(semantic-lex-make-type-table):
* lisp/completion.el (cmpl-prefix-obarray, cmpl-obarray)
(clear-all-completions):
* lisp/emacs-lisp/checkdoc.el (checkdoc-defun-info):
* lisp/emacs-lisp/eldoc.el (eldoc-message-commands)
(eldoc-edit-message-commands):
* lisp/mail/mail-extr.el (mail-extr-all-top-level-domains):
* lisp/mail/rmailkwd.el (rmail-label-obarray):
* lisp/net/dns.el (dns-cache):
* lisp/net/eww.el (eww-suggested-uris):
* lisp/net/imap.el (imap-open, imap-mailbox-select-1)
(imap-message-copyuid-1, imap-message-appenduid-1):
* lisp/obsolete/pgg.el (pgg-passphrase-cache, pgg-pending-timers):
* lisp/play/cookie1.el (cookie-cache):
* lisp/progmodes/cc-defs.el (c-lang-constants, c-define-lang-constant):
* lisp/progmodes/cc-langs.el (c-keywords-obarray):
* lisp/vc/vc-hooks.el (vc-file-prop-obarray):
* test/lisp/obarray-tests.el (obarrayp-test):
* test/src/minibuf-tests.el (minibuf-tests--strings-to-obarray):
Use obarray-make instead of obarray-make.

For bug#64939.

* lisp/files.el (auto-mode-interpreter-regexp): Account for possible
VARIABLE=[VALUE] operands.
* test/lisp/files-tests.el (files-tests-auto-mode-interpreter):
Add an example from the coreutils manual.

This is not an exact re-implementation of what env accepts, but
hopefully it should be "good enough".

Example of known limitation: we assume that arguments for
--long-options will be set with '=', but that is not
necessarily the case.  '--unset' (mandatory argument) can be
passed as '--unset=VAR' or '--unset VAR', but
'--default-signal' (optional argument) requires an '=' sign.

For bug#64939.

* lisp/files.el (auto-mode-interpreter-regexp): Account for
supplementary arguments passed beside -S/--split-string.
* test/lisp/files-tests.el (files-tests-auto-mode-interpreter):
Test some of these combinations.

* test/lisp/files-tests.el (files-tests--check-shebang): For
shell-script modes, verify that the correct shell is set.
(files-tests-auto-mode-interpreter): Prefer 'sh-base-mode' to
'sh-mode' to stay tree-sitter-agnostic; re-organize test cases to
make future ones easier to add.

* lisp/erc/erc-backend.el (erc-query-buffer-p): Remove forward declaration.
* lisp/erc/erc.el (erc-query-buffer-p): Defer to `erc-channel-p'.
(erc-channel-p): Refactor and use `erc--fallback-channel-prefixes' for
the default CHANTYPES value.  Honor an empty CHANTYPES value as valid,
e.g., for servers that only support direct messages.
(erc--fallback-channel-prefixes): New variable to hold fallback
CHANTYPES prefixes recommended by RFC1459 and modern authorities on
the matter.
* test/lisp/erc/erc-tests.el (erc-channel-p): Revise test.  (Bug#67220)

* lisp/erc/erc-backend.el (erc-server-parameters)
(erc--isupport-params): Mention parsing and storage behavior regarding
nonstandard "FOO=" tokens.
(erc--parse-isupport-value): Move comment closer to code.
(erc--get-isupport-entry): Treat the empty string as truly null, as
prescribed by the Brocklesby draft cited in the top-level comment.
* test/lisp/erc/erc-tests.el (erc--get-isupport-entry): Add case for
the empty string appearing as a value for an `erc-server-parameters'
item.
(erc-server-005): Assert compat-related behavior of retaining the
empty string as a valid value from a raw "FOO=" token.
(Bug#67220)

* lisp/erc/erc-fill.el (erc-fill-mode): Add reference to
`erc-fill-wrap-mode' in doc string.
(erc--fill-wrap-scrolltobottom-exempt-p): New variable to allow tests
involving `fill-wrap' to opt out of having to enable `scrolltobottom'.
(erc-fill--wrap-ensure-dependencies): Warn and enable
`erc-scrolltobottom-mode' if necessary.
(erc-fill-wrap-mode): Mention workaround for automatically enabling
`scrolltobottom'.
* test/lisp/erc/erc-fill-tests.el (erc-fill-tests--wrap-populate):
Exempt tests from `scrolltobottom' dependency.
* test/lisp/erc/resources/erc-scenarios-common.el: Load `erc-fill'
when compiling.
(erc-scenarios-common--print-trace): Exempt tests using `fill-wrap'
from the `scrolltobottom' dependency by making
`erc--fill-wrap-scrolltobottom-exempt-p' non-nil during test runs.
(Bug#60936)

Avoid eager macro-expansion error in tests files on Emacs 27 and 28 by
ensuring definitions provided by Compat, like `macroexp-file-name',
load first.

* lisp/erc/erc-speedbar.el (erc-speedbar--reset-last-ran-on-timer):
Suppress "`buffer-local-value' is an obsolete generalized variable"
warning on Emacs 29 and below.
* lisp/erc/erc-stamp.el (erc-stamp--time-as-day): Avoid "unused
lexical variable `current-time-list'" warning on 28 and below.
* lisp/erc/erc.el (erc-check-text-conversion): Add `defvar' for
`text-conversion-style' to avoid "reference to free variable" warning
on Emacs 29 and below.
* test/lisp/erc/erc-button-tests.el: Load `erc-button' before `ert-x'.
* test/lisp/erc/erc-fill-tests.el: Load `erc-fill' before `ert-x'.
* test/lisp/erc/erc-goodies-tests.el: Load `erc-goodies' before
`ert-x'.
* test/lisp/erc/erc-networks-tests.el: Explicitly load `erc-compat'
before anything else.
* test/lisp/erc/erc-scenarios-base-renick.el: Update timeouts.
* test/lisp/erc/erc-stamp-tests.el: Load `erc-stamp' before `ert-x'.
* test/lisp/erc/erc-tests.el: Load `erc-ring' before `ert-x'.

* lisp/eshell/esh-opt.el (eshell--get-option-symbols): New function...
(eshell-eval-using-options): ... use it.
(eshell--do-opts, eshell--process-args): Take OPTION-SYMS.

* test/lisp/eshell/esh-opt-tests.el (esh-opt-test/process-args):
(esh-opt-test/process-args-parse-leading-options-only):
(esh-opt-test/process-args-external): Pass OPTION-SYMS in.