NEWS 50.6 KB
Newer Older
1
GNU Emacs NEWS -- history of user-visible changes.
2

Paul Eggert's avatar
Paul Eggert committed
3
Copyright (C) 2017-2018 Free Software Foundation, Inc.
4
See the end of the file for license conditions.
Dave Love's avatar
#  
Dave Love committed
5

6 7
Please send Emacs bug reports to 'bug-gnu-emacs@gnu.org'.
If possible, use 'M-x report-emacs-bug'.
8

9
This file is about changes in Emacs version 27.
10

Paul Eggert's avatar
Paul Eggert committed
11
See file HISTORY for a list of GNU Emacs versions and release dates.
12 13
See files NEWS.26, NEWS.25, ..., NEWS.18, and NEWS.1-17 for changes
in older Emacs versions.
14

Paul Eggert's avatar
Paul Eggert committed
15
You can narrow news to a specific version by calling 'view-emacs-news'
16
with a prefix argument or by typing 'C-u C-h C-n'.
17

18 19 20 21 22
Temporary note:
+++ indicates that all necessary documentation updates are complete.
    (This means all relevant manuals in doc/ AND lisp doc-strings.)
--- means no change in the manuals is needed.
When you add a new item, use the appropriate mark if you are sure it applies,
Eli Zaretskii's avatar
Eli Zaretskii committed
23

Michael Albinus's avatar
Michael Albinus committed
24

25
* Installation Changes in Emacs 27.1
Paul Eggert's avatar
Paul Eggert committed
26

27 28 29
** Emacs now uses GMP, the GNU Multiple Precision library.
By default, if 'configure' does not find a suitable libgmp, it
arranges for the included mini-gmp library to be built and used.
30
The new 'configure' option '--without-libgmp' uses mini-gmp even if a
31
suitable libgmp is available.
Tom Tromey's avatar
Tom Tromey committed
32

33
** The new configure option '--with-json' adds support for JSON using
34
the Jansson library.  It is on by default; use './configure
35 36 37 38 39
--with-json=no' to build without Jansson support.  The new JSON
functions 'json-serialize', 'json-insert', 'json-parse-string', and
'json-parse-buffer' are typically much faster than their Lisp
counterparts from json.el.

Paul Eggert's avatar
Paul Eggert committed
40 41 42 43 44 45 46
** The etags program now uses the C library's regular expression matcher
when possible, and a compatible regex substitute otherwise.  This will
let developers maintain Emacs's own regex code without having to also
support other programs.  The new configure option '--without-included-regex'
forces etags to use the C library's regex matcher even if the regex
substitute ordinarily would be used to work around compatibility problems.

47
** Emacs has been ported to the '-fcheck-pointer-bounds' option of GCC.
48 49 50 51 52 53
This causes Emacs to check bounds of some arrays addressed by its
internal pointers, which can be helpful when debugging the Emacs
interpreter or modules that it uses.  If your platform supports it you
can enable it when configuring, e.g., './configure CFLAGS="-g3 -O2
-mmpx -fcheck-pointer-bounds"' on Intel MPX platforms.

54 55 56
** Emacs now normally uses a C pointer type instead of a C integer
type to implement Lisp_Object, which is the fundamental machine word
type internal to the Emacs Lisp interpreter.  This change aims to
57 58
catch typos and supports '-fcheck-pointer-bounds'.  The 'configure'
option '--enable-check-lisp-object-type' is therefore no longer as
59 60 61
useful and so is no longer enabled by default in developer builds,
to reduce differences between developer and production builds.

62 63
** Ibuffer

64 65 66 67 68
---
*** All mode filters can now accept a list of symbols.
This means you can now easily filter several major modes, as well
as a single mode.

69 70 71 72 73 74 75
** Gnus

+++
*** The nnimap backend now has support for IMAP namespaces.
This feature can be enabled by setting the new 'nnimap-use-namespaces'
server variable to non-nil.

76

77
* Startup Changes in Emacs 27.1
78

79 80 81 82 83 84 85 86 87
+++
** Emacs can now be configured using an early init file.
The file is called 'early-init.el', in 'user-emacs-directory'.  It is
loaded very early in the startup process: before graphical elements
such as the tool bar are initialized, and before the package manager
is initialized.  The primary purpose is to allow customizing how the
package system is initialized given that initialization now happens
before loading the regular init file (see below).

88 89 90 91 92 93 94
We recommend against putting any customizations in this file that
don't need to be set up before initializing installed add-on packages,
because the early init file is read too early into the startup
process, and some important parts of the Emacs session, such as
window-system and other GUI features, are not yet set up, which could
make some customization fail to work.

95
+++
96
** Installed packages are now activated *before* loading the init file.
97 98 99 100
This is part of a change intended to eliminate the behavior of
package.el inserting a call to 'package-initialize' into the init
file, which was previously done when Emacs was started.  As a result
of this change, it is no longer necessary to call 'package-initialize'
101 102 103 104 105 106 107
in your init file.

However, if your init file changes the values of 'package-load-list' or
'package-user-dir', or sets 'package-enable-at-startup' to nil then it won't
work right without some adjustment:
- you can move that code to the early init file (see above), so those settings
  apply before Emacs tries to activate the packages.
108
- you can use the new 'package-quickstart' so activation of packages does not
109
  need to pay attention to 'package-load-list' or 'package-user-dir' any more.
110

111 112 113 114 115
---
** Emacs now notifies systemd when startup finishes or shutdown begins.
Units that are ordered after 'emacs.service' will only be started
after Emacs has finished initialization and is ready for use.
(If your Emacs is installed in a non-standard location and you copied the
116
emacs.service file to eg "~/.config/systemd/user/", you will need to copy
117 118
the new version of the file again.)

119

120
* Changes in Emacs 27.1
121

122 123
** emacsclient

124
+++
125
*** emacsclient now supports the 'EMACS_SOCKET_NAME' environment variable.
Eli Zaretskii's avatar
Eli Zaretskii committed
126 127
The behavior is identical to 'EMACS_SERVER_FILE', in that the
command-line value specified via '--socket-name' will override the
128
environment, and the natural default to TMPDIR, then "/tmp", continues
Eli Zaretskii's avatar
Eli Zaretskii committed
129
to apply.
130

131 132 133 134
---
*** When run by root, emacsclient no longer connects to non-root sockets.
(Instead you can use Tramp methods to run root commands in a non-root Emacs.)

Tino Calancha's avatar
Tino Calancha committed
135 136 137
+++
** The function 'read-passwd' uses '*' as default character to hide passwords.

138 139 140 141 142 143
---
** The new option 'tooltip-resize-echo-area' avoids truncating tooltip text
on GUI frames when tooltips are displayed in the echo area.  Instead,
it resizes the echo area as needed to accommodate the full tool-tip
text.

144
---
145
** Show mode line tooltips only if the corresponding action applies.
146 147 148 149
Customize the option 'mode-line-default-help-echo' to restore the old
behavior where the tooltip text is also shown when the corresponding
action does not apply.

150 151 152 153 154 155 156 157 158
+++
** New hook 'server-after-make-frame-hook'.
This hook is a convenient place to perform initializations in daemon
mode which require GUI features to be available.  One example is
restoration of the previous session using the desktop.el package: put
the call to 'desktop-read' in this hook, if you want the GUI settings
to be restored, or if desktop.el needs to interact with you during
restoration of the session.

Mark Oteiza's avatar
Mark Oteiza committed
159 160 161
+++
** New function 'logcount' calculates an integer's Hamming weight.

162 163 164 165 166 167 168 169
+++
** New function 'libxml-available-p'.
This function returns non-nil if libxml support is both compiled in
and available at run time.  Lisp programs should use this function to
detect built-in libxml support, instead of testing for that
indirectly, e.g., by checking that functions like
'libxml-parse-html-region' return nil.

170
+++
171
** 'libxml-parse-xml-region' and 'libxml-parse-html' region take
172 173
a parameter that's called DISCARD-COMMENTS, but it really only
discards the top-level comment.  Therefore this parameter is now
174
obsolete, and the new utility function 'xml-remove-comments' can be
175 176 177
used to remove comments before calling the libxml functions to parse
the data.

178 179
+++
** The Network Security Manager now allows more fine-grained control
180
of what checks to run via the 'network-security-protocol-checks'
181 182
variable.

183
+++
184 185 186 187 188 189 190 191 192
** TLS connections have their security tightened by default.
Most of the checks for outdated, believed-to-be-weak TLS algorithms
and ciphers are now switched on by default.  By default, the NSM will
flag connections using these weak algorithms and ask users whether to
allow them.  To get the old behavior back (where certificates are
checked for validity, but no warnings about weak cryptography are
issued), you can either set 'network-security-protocol-checks' to nil,
or adjust the elements in that variable to only happen on the 'high'
security level (assuming you use the 'medium' level).
193

194 195 196 197 198
+++
** New function 'fill-polish-nobreak-p', to be used in 'fill-nobreak-predicate'.
It blocks line breaking after a one-letter word, also in the case when
this word is preceded by a non-space, but non-alphanumeric character.

199 200 201 202 203 204 205
+++
** The limit on repetitions in regexps has been raised to 2^16-1.
It was previously limited to 2^15-1.  For example, the following
regular expression was previously invalid, but is now accepted:

   x\{32768\}

206 207 208
---
** The German prefix and postfix input methods now support Capital sharp S.

209
---
210
** New input methods 'hawaiian-postfix' and 'hawaiian-prefix'.
211

212
+++
213 214 215 216
** New function 'exec-path'.
This function by default returns the value of the corresponding
variable, but can optionally return the equivalent of 'exec-path'
from a remote host.
217 218

+++
219 220
** The function 'executable-find' supports an optional argument REMOTE.
This triggers to search the program on the remote host as indicated by
221 222
'default-directory'.

223 224 225 226 227
+++
** New variable 'auto-save-no-message'.
When set to t, no message will be shown when auto-saving (default
value: nil).

228 229 230 231 232 233
---
** The value of 'make-cursor-line-fully-visible' can now be a function.
In addition to nil or non-nil, the value can now be a predicate
function.  Follow mode uses this to control scrolling of its windows
when the last screen line in a window is not fully visible.

234 235 236 237
+++
** New variable 'emacs-repository-branch'.
It reports the git branch from which Emacs was built.

238

239
* Editing Changes in Emacs 27.1
240

241 242 243
+++
** New command 'make-empty-file'.

244 245 246 247 248
---
** New variable 'x-wait-for-event-timeout'.
This controls how long Emacs will wait for updates to the graphical
state to take effect (making a frame visible, for example).

249
+++
250 251 252 253
** New user option 'electric-quote-replace-double'.
This option controls whether '"' is replaced in 'electric-quote-mode',
in addition to other quote characters.  If non-nil, ASCII double-quote
characters that quote text "like this" are replaced by double
254 255
typographic quotes, “like this”, in text modes, and in comments in
non-text modes.
256

257 258 259 260 261 262 263
---
** New user option 'flyspell-case-fold-duplications'.
This option controls whether Flyspell mode considers consecutive words
to be duplicates if they are not in the same case.  If non-nil, the
default, words are considered to be duplicates even if their letters'
case does not match.

264 265 266 267 268
---
** 'write-abbrev-file' now includes special properties.
'write-abbrev-file' now writes special properties like ':case-fixed'
for abbrevs that have them.

Allen Li's avatar
Allen Li committed
269
+++
Allen Li's avatar
Allen Li committed
270 271 272
** 'write-abbrev-file' skips empty tables.
'write-abbrev-file' now skips inserting a 'define-abbrev-table' form for
tables which do not have any non-system abbrevs to save.
Allen Li's avatar
Allen Li committed
273

274
+++
275 276
** The new functions and commands 'text-property-search-forward' and
'text-property-search-backward' have been added.  These provide an
277
interface that's more like functions like 'search-forward'.
278

Juri Linkov's avatar
Juri Linkov committed
279 280
---
** More commands support noncontiguous rectangular regions, namely
Michael Albinus's avatar
Michael Albinus committed
281
'upcase-dwim', 'downcase-dwim', 'replace-string', 'replace-regexp'.
Juri Linkov's avatar
Juri Linkov committed
282

283 284 285 286 287 288 289
+++
** When asked to visit a large file, Emacs now offers visiting it literally.
Previously, Emacs would only ask for confirmation before visiting
large files.  Now it also offers a third alternative: to visit the
file literally, as in 'find-file-literally', which speeds up
navigation and editing of large files.

290
---
291 292 293 294
** 'add-dir-local-variable' now uses dotted pair notation syntax to
write alists of variables to ".dir-locals.el".  This is the same
syntax that you can see in the example of a ".dir-locals.el" file in
the node "(emacs) Directory Variables" of the user manual.
295

Michael Albinus's avatar
Michael Albinus committed
296

297
* Changes in Specialized Modes and Packages in Emacs 27.1
298

299 300 301 302 303 304
---
** Follow mode
In the current follow group of windows, "ghost" cursors are no longer
displayed in the non-selected follow windows.  To get the old behavior
back, customize follow-hide-ghost-cursors to nil.

305 306 307 308 309
** Windmove

*** windmove-create-window when non-nil makes a new window on moving off
the edge of the frame.

310 311 312 313
** Octave mode
The mode is automatically enabled in files that start with the
'function' keyword.

Stefan Monnier's avatar
Stefan Monnier committed
314 315 316 317 318 319 320 321 322 323 324
** project.el
*** New commands project-search and project-query-replace

** Etags
+++
*** 'next-file' is now an obsolete alias of tags-next-file
*** tags-loop-revert-buffers is an obsolete alias of multifile-revert-buffers
*** The tags-loop-continue function along with the tags-loop-operate and
tags-loop-scan variables are now obsolete; use the new multifile-initialize and
multifile-continue functions instead.

325 326 327 328 329 330
---
** bibtex
*** New commands 'bibtex-next-entry' and 'bibtex-previous-entry'.
In bibtex-mode-map, forward-paragraph and backward-paragraph are
remapped to these, respectively.

331 332 333 334 335
+++
** Dired

*** New command 'dired-create-empty-file'.

336 337
** Change Logs and VC

Eli Zaretskii's avatar
Eli Zaretskii committed
338 339 340 341 342 343 344 345
*** Recording ChangeLog entries doesn't require an actual file.
If a ChangeLog file doesn't exist, and if the new variable
'add-log-dont-create-changelog-file' is non-nil (which is the
default), commands such as 'C-x 4 a' will add log entries to a
suitable named temporary buffer.  (An existing ChangeLog file will
still be used if it exists.)  Set the variable to nil to get the
previous behavior of always creating a buffer that visits a ChangeLog
file.
346

347 348 349
*** New customizable variable 'vc-find-revision-no-save'.
With non-nil, 'vc-find-revision' doesn't write the created buffer to file.

350 351 352 353
*** New customizable variable 'vc-git-grep-template'.
This new variable allows customizing the default arguments passed to
git-grep when 'vc-git-grep' is used.

354 355 356 357
*** Command 'vc-git-stash' now respects marks in the '*vc-dir*' buffer.
When some files are marked, only those are stashed.
When no files are marked, all modified files are stashed, as before.

358 359
*** The new hook 'vc-retrieve-tag-hook' runs after retrieving a tag.

Eli Zaretskii's avatar
Eli Zaretskii committed
360 361 362
---
*** 'vc-hg' now invokes 'smerge-mode' when visiting files.
Code that attempted to invoke 'smerge-mode' when visiting an Hg file
363 364 365 366
with conflicts existed in earlier versions of Emacs, but incorrectly
never detected a conflict due to invalid assumptions about cached
values.

367
** diff-mode
368
*** Hunks are now automatically refined by default.
369 370
To disable it, set the new defcustom 'diff-font-lock-refine' to nil.

371
*** File headers can be shortened, mimicking Magit's diff format.
372 373
To enable it, set the new defcustom 'diff-font-lock-prettify to t.

374
+++
375 376 377 378
*** Prefix arg of 'diff-goto-source' means jump to the old revision
of the file under version control if point is on an old changed line,
or to the new revision of the file otherwise.

379
** Browse-url
380

381 382 383 384
*** The function 'browse-url-emacs' can now visit a URL in selected window.
It now treats the optional 2nd argument to mean that the URL should be
shown in the currently selected window.

385
** Comint
386

387
+++
388
*** 'send-invisible' is now an obsolete alias for 'comint-send-invisible'.
389 390
Also, 'shell-strip-ctrl-m' is declared obsolete.

391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406
+++
*** 'C-c .' (comint-insert-previous-argument) no longer interprets '&'.
This feature caused problems when '&&' was present in the previous
command.  Since this command emulates 'M-.' in Bash and zsh, neither
of which treats '&' specially, the feature was removed for
compatibility with these shells.

+++
*** 'comint-insert-previous-argument' can now count arguments from the end.
By default, invoking 'C-c .' with a numeric argument N would copy the
Nth argument, counting from the first one.  But if the new option
'comint-insert-previous-argument-from-end' is non-nil, it will copy
the Nth argument counting from the last one.  Thus 'C-c .' can now
better emulate 'M-.' in both Bash and zsh, since the former counts
from the beginning of the arguments, while the latter counts from the
end.
407

408 409 410 411 412 413 414 415 416 417 418 419 420 421 422
** SQL

*** Installation of 'sql-indent' from ELPA is strongly encouraged.
This package support sophisticated rules for properly indenting SQL
statements.  SQL is not like other programming languages like C, Java,
or Python where code is sparse and rules for formatting are fairly
well established. Instead SQL is more like COBOL (from which it came)
and code tends to be very dense and line ending decisions driven by
syntax and line length considerations to make readable code.
Experienced SQL developers may prefer to rely upon existing Emacs
facilities for formatting code but the 'sql-indent' package provides
facilities to aid more casual SQL developers layout queries and
complex expressions.

*** 'sql-use-indent-support' (default t) enables SQL indention support.
423
The 'sql-indent' package from ELPA must be installed to get the
424 425 426 427 428 429 430
indentation support in 'sql-mode' and 'sql-interactive-mode'.

*** 'sql-mode-hook' and 'sql-interactive-mode-hook' changed.
Both hook variables have had 'sql-indent-enable' added to their
default values. If youhave existing customizations to these variables,
you should make sure that the new default entry is included.

431 432 433 434 435
** Term

---
*** 'term-read-noecho' is now obsolete, use 'read-passwd' instead.

436 437 438
** Flymake

+++
439
*** The variable 'flymake-diagnostic-types-alist' is obsolete.
440 441 442
You should instead set properties on known diagnostic symbols, like
':error' and ':warning', as demonstrated in the Flymake manual.

443
*** New customizable variable 'flymake-start-on-save-buffer'.
444 445
Control whether Flymake starts checking the buffer on save.

446
*** Flymake and backend functions may exchange hints about buffer changes.
447 448 449
This enables more efficient backends.  See the docstring of
'flymake-diagnostic-functions' or the Flymake manual for details.

450
** Package
451

452
*** New function 'package-get-version' lets packages query their own version.
453 454
Example use in auctex.el: (defconst auctex-version (package-get-version))

455
*** New 'package-quickstart' feature.
456 457 458 459 460 461 462 463 464
When 'package-quickstart' is non-nil, package.el precomputes a big autoloads
file so that activation of packages can be done much faster, which can speed up
your startup significantly.
It also causes variables like package-user-dir and package-load-list to be
consulted when 'package-quickstart-refresh' is run rather than at startup so
you don't need to set them in your early init file.

*** New function 'package-activate-all'.

465 466 467 468 469 470 471 472 473
** Info

---
*** Info can now follow 'file://' protocol URLs.
The 'file://' URLs in Info documents can now be followed by passing
them to the 'browse-url' function, like the other protocols: ftp,
http, and https.  This allows to have references to local HTML files,
for example.

474 475 476 477 478 479 480
** Xref

+++
*** New command 'xref-find-definitions-at-mouse'.
This command finds definitions of the identifier at the place of a
mouse click event, and is intended to be bound to a mouse event.

481 482 483 484 485
+++
*** Changing 'xref-marker-ring-length' works after 'xref.el' is loaded.
Previously, setting 'xref-marker-ring-length' would only take effect
if set before 'xref.el' was loaded.

486
** Ecomplete
487

488
*** The ecomplete sorting has changed to a decay-based algorithm.
489
This can be controlled by the new 'ecomplete-sort-predicate' variable.
490

491
*** The 'ecompleterc' file is now placed in ~/.emacs.d/ecompleterc by default.
492 493
Of course it will still find it if you have it in ~/.ecompleterc

Paul Eggert's avatar
Paul Eggert committed
494
** Gnus
495 496

+++
497
*** A prefix argument to 'gnus-summary-limit-to-score' will limit reverse.
498 499
Limit to articles with score at below.

Paul Eggert's avatar
Paul Eggert committed
500 501 502
*** The function 'gnus-score-find-favorite-words' has been renamed
from 'gnus-score-find-favourite-words'.

503 504 505 506
---
*** Gmane has been removed as an nnir backend, since Gmane no longer
has a search engine.

507
+++
508 509
*** Splitting mail on common mailing list headers has been added.
See the concept index in the Gnus manual for the 'match-list' entry.
510

511
+++
512
*** nil is no longer an allowed value for 'mm-text-html-renderer'.
513

514
+++
515 516
*** A new Gnus summary mode command, 'S A'
('gnus-summary-attach-article') can be used to attach the current
517 518 519
article(s) to a pre-existing Message buffer, or create a new Message
buffer with the article(s) attached.

520 521 522 523 524
---
*** New option 'nnir-notmuch-filter-group-names-function'.
This option controls whether and how to use Gnus search groups as
'path:' search terms to 'notmuch'.

525 526 527
** erc

---
528
*** 'erc-button-google-url' has been renamed 'erc-button-search-url'
529 530
and its value has been changed to Duck Duck Go.

531 532 533 534
** EUDC

*** XEmacs support has been removed.

535 536 537
** eww/shr

*** When opening external links in eww/shr (typically with the
538 539
'C-u RET' keystroke on a link), the link will be flashed with the new
'shr-selected-link' face to give the user feedback that the command
540 541
has been executed.

542 543 544 545 546
+++
*** New option 'shr-discard-aria-hidden'.
If set, shr will not render tags with attribute 'aria-hidden="true"'.
This attribute is meant to tell screen readers to ignore a tag.

Paul Eggert's avatar
Paul Eggert committed
547
** Htmlfontify
548

Paul Eggert's avatar
Paul Eggert committed
549 550 551 552 553
*** The functions 'hfy-color', 'hfy-color-vals' and
'hfy-fallback-color-values' and the variables 'hfy-fallback-color-map'
and 'hfy-rgb-txt-color-map' have been renamed from names that used
'colour' instead of 'color'.

554 555 556 557 558 559 560 561
+++
** Enriched mode supports the 'charset' text property.
You can add or modify the 'charset' text properties of text using the
Edit->Text Properties->Special Properties menu, or by invoking the
'facemenu-set-charset' command.  Documents in Enriched mode will be
saved with the charset properties, and those properties will be
restored when the file is visited.

562
** Smtpmail
563

564 565 566
Authentication mechanisms can be added via external packages, by
defining new cl-defmethod of smtpmail-try-auth-method.

567
** Footnote-mode
568

569 570 571 572
*** Support Hebrew-style footnotes
*** Footnote text lines are now aligned.
Can be controlled via the new variable 'footnote-align-to-fn-text'.

573 574 575 576 577 578 579
** CSS mode

---
*** A new command 'css-cycle-color-format' for cycling between color
formats (e.g. "black" => "#000000" => "rgb(0, 0, 0)") has been added,
bound to 'C-c C-f'.

580 581 582
---
*** CSS mode, SCSS mode, and Less CSS mode now have support for Imenu.

583 584 585 586 587 588 589
** SGML mode

---
*** 'sgml-quote' now handles double quotes and apostrophes
when escaping text and in addition all numeric entities when
unescaping text.

590 591 592 593 594 595 596
** Python mode

---
*** Python mode supports three different font lock decoration levels.
The maximum level is used by default; customize
'font-lock-maximum-decoration' to tone down the decoration.

597 598 599 600 601 602 603
** Dired

+++
*** The new user option 'dired-create-destination-dirs' controls whether
'dired-do-copy' and 'dired-rename-file' should create non-existent
directories in the destination.

604 605
** Help

606 607 608 609 610 611 612
---
*** Output format of 'C-h l' (view-lossage) has changed.
For convenience, 'view-lossage' now displays the last keystrokes
and commands in the same format as the edit buffer of
'edit-last-kbd-macro'.  This makes it possible to copy the lines from
the buffer generated by 'view-lossage' to the "*Edit Macro*" buffer
created by 'edit-last-kbd-macro', and to save the macro by 'C-c C-c'.
613

614 615 616 617
---
*** The list of help commands produced by 'C-h C-h' ('help-for-help')
can now be searched via 'C-s'.

618 619 620 621 622
** Ibuffer

---
*** New filter ibuffer-filter-by-process; bound to '/E'.

623 624
** Search and Replace

Juri Linkov's avatar
Juri Linkov committed
625 626 627 628 629 630
*** isearch-lazy-count shows the current match number and total number
of matches in the Isearch prompt.  Customizable variables
lazy-count-prefix-format and lazy-count-suffix-format define the
format of the current and the total number of matches in the prompt's
prefix and suffix respectively.

631 632 633 634 635 636 637 638
*** lazy-highlight-buffer highlights matches in the full buffer.
It is useful in combination with lazy-highlight-cleanup customized to nil
to leave matches highlighted in the whole buffer after exiting isearch.
Also when lazy-highlight-buffer prepares highlighting in the buffer,
navigation through the matches without flickering is more smooth.
lazy-highlight-buffer-max-at-a-time controls the number of matches to
highlight in one iteration while processing the full buffer.

Juri Linkov's avatar
Juri Linkov committed
639 640
+++
*** New isearch bindings.
641

Juri Linkov's avatar
Juri Linkov committed
642
'C-M-w' in isearch changed from isearch-del-char to the new function
643 644
isearch-yank-symbol-or-char.  isearch-del-char is now bound to
'C-M-d'.
Juri Linkov's avatar
Juri Linkov committed
645

646
+++
647 648 649 650 651 652
*** 'search-exit-option' provides new options 'move' and 'shift-move'
to extend the search string by yanking text that ends at the new
position after moving point in the current buffer.  'shift-move'
extends the search string by motion commands while holding down
the shift key.

Juri Linkov's avatar
Juri Linkov committed
653 654 655 656
---
*** Isearch now remembers the regexp-based search mode for words/symbols
and case-sensitivity together with search strings in the search ring.

657 658 659 660 661
** Debugger

+++
*** The Lisp Debugger is now based on 'backtrace-mode'.
Backtrace mode adds fontification and commands for changing the
662 663
appearance of backtrace frames.  See the node "(elisp) Backtraces" in
the Elisp manual for documentation of the new mode and its commands.
664

665 666 667 668
** Edebug

+++
*** The runtime behavior of Edebug's instrumentation can be changed
669 670
using the new variables 'edebug-behavior-alist',
'edebug-after-instrumentation-function' and
671
'edebug-new-definition-function'.  Edebug's behavior can be changed
672 673
globally or for individual definitions.

674
+++
675 676
*** Edebug's backtrace buffer now uses 'backtrace-mode'.
Backtrace mode adds fontification, links and commands for changing the
677 678
appearance of backtrace frames.  See the node "(elisp) Backtraces" in
the Elisp manual for documentation of the new mode and its commands.
679

680 681 682 683 684 685 686 687 688
The binding of 'd' in Edebug's keymap is now 'edebug-pop-to-backtrace'
which replaces 'edebug-backtrace'.  Consequently Edebug's backtrace
windows now behave like those of the Lisp Debugger and of ERT, in that
when they appear they will be the selected window.

The new 'backtrace-goto-source' command, bound to 's', works in
Edebug's backtraces on backtrace frames whose source code has
been instrumented by Edebug.

689 690
** Enhanced xterm support

Mark Oteiza's avatar
Mark Oteiza committed
691 692 693
*** New variable 'xterm-set-window-title' controls whether Emacs sets
the XTerm window title.  This feature is experimental and is disabled
by default.
694

695 696
** grep

697
+++
698 699
*** rgrep, lgrep and zrgrep now hide part of the command line
that contains a list of ignored directories and files.
700 701 702 703
Clicking on the button with ellipsis unhides it.
The abbreviation can be disabled by the new option
'grep-find-abbreviate'.  The new command
'grep-find-toggle-abbreviation' toggles it interactively.
704

Paul Pogonyshev's avatar
Paul Pogonyshev committed
705 706 707 708 709 710
** ERT

+++
*** New variable 'ert-quiet' allows to make ERT output in batch mode
less verbose by removing non-essential information.

711 712 713
+++
*** ERT's backtrace buffer now uses 'backtrace-mode'.
Backtrace mode adds fontification and commands for changing the
714 715
appearance of backtrace frames.  See the node "(elisp) Backtraces" in
the Elisp manual for documentation of the new mode and its commands.
716 717 718

** Gamegrid

719 720
---
*** Gamegrid now determines its default glyph size based on display
721
dimensions, instead of always using 16 pixels.  As a result, Tetris,
722 723
Snake and Pong are more playable on HiDPI displays.

724 725 726 727 728 729
** Filecache

---
*** Completing filenames in the minibuffer via 'C-TAB' now uses the
styles as configured by the variable 'completion-styles'.

730 731 732 733
** New macros 'thunk-let' and 'thunk-let*'.
These macros are analogue to 'let' and 'let*', but create bindings that
are evaluated lazily.

734 735
** next-error

736
+++
737
*** New customizable variable 'next-error-find-buffer-function'.
738 739 740 741 742 743 744 745 746
The value should be a function that determines how to find the
next buffer to be used by 'next-error' and 'previous-error'.  The
default is to use the last buffer that navigated to the current
error.

+++
*** New command 'next-error-select-buffer'.
It can be used to set any buffer as the next one to be used by
'next-error' and 'previous-error'.
747 748 749

** nxml-mode

Eli Zaretskii's avatar
Eli Zaretskii committed
750 751
---
*** The default value of 'nxml-sexp-element-flag' is now t.
752
This means that pressing 'C-M-SPACE' now selects the entire tree by
753 754
default, and not just the opening element.

755 756 757 758 759 760 761 762 763
** Eshell

---
*** Expansion of history event designators is disabled by default.
To restore the old behavior, use

    (add-hook 'eshell-expand-input-functions
              #'eshell-expand-history-references)

Glenn Morris's avatar
Glenn Morris committed
764 765
---
*** The function 'eshell-uniquify-list' has been renamed from
Paul Eggert's avatar
Paul Eggert committed
766 767
'eshell-uniqify-list'.

768 769
*** The function 'eshell/kill' is now able to handle signal switches.
Previously 'eshell/kill' would fail if provided a kill signal to send to the
770 771
process.  It now accepts signals specified either by name or by its number.

772 773 774 775 776
** Shell

---
*** Program name completion inside remote shells works now as expected.

Paul Eggert's avatar
Paul Eggert committed
777 778 779 780
** Pcomplete
*** The function 'pcomplete-uniquify-list' has been renamed from
'pcomplete-uniqify-list'.

Michael Albinus's avatar
Michael Albinus committed
781 782 783
** Auth-source

---
784
*** The Secret Service backend supports the ':create' key now.
Michael Albinus's avatar
Michael Albinus committed
785

786 787 788
** Tramp

+++
789
*** New connection method "nextcloud", which allows to access OwnCloud
790 791
or NextCloud hosted files and directories.

792 793 794 795
+++
*** Connection methods "obex" and "synce" are removed, because they
are obsoleted in GVFS.

Michael Albinus's avatar
Michael Albinus committed
796 797 798
+++
*** Validated passwords are saved by auth-source backends which support this.

799 800 801
+++
*** During user and host name completion in the minibuffer, results
from auth-source search are taken into account.  This can be disabled
802
by setting the user option 'tramp-completion-use-auth-sources' to nil.
803

Michael Albinus's avatar
Michael Albinus committed
804 805 806 807
+++
*** The user option 'tramp-ignored-file-name-regexp' allows to disable
Tramp for some look-alike remote file names.

808 809 810 811
+++
*** For some connection methods, like "su" or "sudo", the host name in
ad-hoc multi-hop file names must match the previous hop.

812 813 814 815 816 817 818
** Rcirc

---
*** New user option 'rcirc-url-max-length'.
Setting this option to an integer causes URLs displayed in Rcirc
buffers to be truncated to that many characters.

819
** Register
820
---
821 822 823
*** The return value of method 'register-val-describe' includes the
names of buffers shown by the windows of a window configuration.

824
---
825 826 827
** The options.el library has been removed.
It was obsolete since Emacs 22.1, replaced by customize.

828 829 830 831
** The tls.el and starttls.el libraries are now marked obsolete.
Use of built-in libgnutls based functionality (described in the Emacs
GnuTLS manual) is recommended instead.

832 833 834 835 836
** Message

+++
*** Messages can now be systematically encrypted
when the PGP keyring contains a public key for every recipient.  To
837
achieve this, add 'message-sign-encrypt-if-all-keys-available' to
838 839
'message-send-hook'.

840 841 842 843 844
---
*** When replying a message that have addresses on the form
'"foo@bar.com" <foo@bar.com>', Message will elide the repeated "name"
from the address field in the response.

845
---
846
*** The default of 'message-forward-as-mime' has changed from t to nil
847 848 849
as it has been reported that many recipients can't read forwards that
are formatted as MIME digests.

850
+++
Michael Albinus's avatar
Michael Albinus committed
851
*** 'message-forward-included-headers' has changed its default to
852 853
exclude most headers when forwarding.

854 855 856 857
** EasyPG

---
*** 'epa-pinentry-mode' is renamed to 'epg-pinentry-mode'.
858 859
It now applies to epg functions as well as epa functions.

860 861 862 863 864 865
---
*** The alias functions 'epa--encode-coding-string',
'epa--decode-coding-string', and 'epa--select-safe-coding-system' have
been removed.  Use 'encode-coding-string', 'decode-coding-string', and
'select-safe-coding-system' instead.

866 867 868 869 870 871 872
** Rmail

+++
*** New user option 'rmail-output-reset-deleted-flag'.
If this option is non-nil, messages appended to an output file by the
'rmail-output' command have their Deleted flag reset.

873 874 875 876
*** The command 'rmail-summary-by-senders' with an empty argument
selects the messages to summarize with a regexp that matches the
sender of the current message.

877 878 879 880 881 882 883 884 885 886
** Threads

+++
*** New variable 'main-thread' holds Emacs's main thread.
This is handy in Lisp programs that run on a non-main thread and want
to signal the main thread, e.g., when they encounter an error.

+++
*** 'thread-join' returns the result of the finished thread now.

887 888 889 890
+++
*** 'thread-signal' does not propagate errors to the main thread.
Instead, error messages are just printed in the main thread.

891 892 893
---
*** 'thread-alive-p' is now obsolete, use 'thread-live-p' instead.

894
+++
895 896 897 898 899
*** New command 'list-threads' shows Lisp threads.
See the current list of live threads in a tabulated-list buffer which
automatically updates.  In the buffer, you can use 's q' or 's e' to
signal a thread with quit or error respectively, or get a snapshot
backtrace with 'b'.
900

901 902
---
** thingatpt.el supports a new "thing" called 'uuid'.
903
A symbol 'uuid' can be passed to 'thing-at-point' and it returns the
904 905
UUID at point.

906
** Interactive automatic highlighting
907

908 909
+++
*** 'highlight-regexp' can now highlight subexpressions.
910
The new command accepts a prefix numeric argument to choose the
911
subexpression.
912 913 914 915

** Mouse display of minor mode menu

---
916
*** 'minor-mode-menu-from-indicator' now displays full minor mode name.
917
When there is no menu for a mode, display the mode name after the
918
indicator instead of just the indicator (which is sometimes cryptic).
919

920

921
* New Modes and Packages in Emacs 27.1
922

923
** multifile.el lets one setup multifile operations like search&replace.
Stefan Monnier's avatar
Stefan Monnier committed
924

925
+++
926 927
** Emacs can now visit files in archives as if they were directories.
This feature uses Tramp and works only on systems which support GVFS,
928
i.e. GNU/Linux, roughly spoken.  See the node "(tramp) Archive file
929 930
names" in the Tramp manual for full documentation of these facilities.

João Távora's avatar
João Távora committed
931
+++
932
** New library for writing JSONRPC applications (https://jsonrpc.org).
João Távora's avatar
João Távora committed
933 934 935 936 937 938 939
The 'jsonrpc' library enables writing Emacs Lisp applications that
rely on this protocol.  Since the protocol is designed to be
transport-agnostic, the library provides an API to implement new
transport strategies as well as a separate API to use them.  A
transport implementation for process-based communication, such as is
used by the Language Server Protocol (LSP), is readily available.

940 941 942 943
+++
** Backtrace mode improves viewing of Elisp backtraces.
Backtrace mode adds pretty printing, fontification and ellipsis
expansion to backtrace buffers produced by the Lisp debugger, Edebug
944
and ERT.  See the node "(elisp) Backtraces" in the Elisp manual for
945 946
documentation of the new mode and its commands.

Glenn Morris's avatar
Glenn Morris committed
947 948 949

* Incompatible Lisp Changes in Emacs 27.1

950
** 'define-fringe-bitmap' is always defined, even when Emacs is built
951 952
without any GUI support.

953 954 955
---
** Just loading a theme's file no longer activates the theme's settings.
Loading a theme with 'M-x load-theme' still activates the theme, as it
956
did before.  However, loading the theme's file with 'M-x load-file',
957 958 959 960 961 962 963 964 965 966 967
or using 'require' or 'load' in a Lisp program, doesn't actually apply
the theme's settings until you either invoke 'M-x enable-theme' or
type 'M-x load-theme'.  (In a Lisp program, calling 'enable-theme' or
invoking 'load-theme' with NO-ENABLE argument omitted or nil has the
same effect of activating a theme whose file has been loaded.)  The
special case of the 'user' theme is an exception: it is frequently
used for ad-hoc customizations, so the settings of that theme are by
default applied immediately.

The variable 'custom--inhibit-theme-enable' controls this behavior;
its default value changed in Emacs 27.1.
968

969
** The REPETITIONS argument of 'benchmark-run' can now also be a variable.
970

971 972 973 974 975 976
** Interpretation of relative HOME directory has changed.
If $HOME is set to a relative file name, 'expand-file-name' now
interprets it relative to the directory where Emacs was started, not
relative to the default-directory of the current buffer.  We recommend
always setting $HOME to an absolute file name, so that its meaning is
independent of where Emacs was started.
977

Glenn Morris's avatar
Glenn Morris committed
978 979 980 981 982 983 984 985 986 987
** The FILENAME argument to 'file-name-base' is now mandatory and no
longer defaults to 'buffer-file-name'.

---
** The function 'eldoc-message' now accepts a single argument.
Programs that called it with multiple arguments before should pass
them through 'format' first.  Even that is discouraged: for ElDoc
support, you should set 'eldoc-documentation-function' instead of
calling 'eldoc-message' directly.

988 989 990 991
** Old-style backquotes now generate an error.
They have been generating warnings for a decade.  To interpret
old-style backquotes as new-style, bind the new variable
'force-new-style-backquotes' to t.
Glenn Morris's avatar
Glenn Morris committed
992 993 994 995 996 997 998

** Defining a Common Lisp structure using 'cl-defstruct' or
'cl-struct-define' whose name clashes with a builtin type (e.g.,
'integer' or 'hash-table') now signals an error.

** When formatting a floating-point number as an octal or hexadecimal
integer, Emacs now signals an error if the number is too large for the
999
implementation to format.
Glenn Morris's avatar
Glenn Morris committed
1000

1001
---
Glenn Morris's avatar
Glenn Morris committed
1002
** Some functions and variables obsolete since Emacs 22 have been removed:
1003 1004 1005 1006 1007 1008
archive-mouse-extract, assoc-ignore-case, assoc-ignore-representation,
backward-text-line, blink-cursor, bookmark-exit-hooks,
comint-use-prompt-regexp-instead-of-fields, compilation-finish-function,
count-text-lines, cperl-vc-header-alist, custom-face-save-command,
cvs-display-full-path, cvs-fileinfo->full-path, delete-frame-hook,
derived-mode-class, describe-char-after, describe-project,
Michael Albinus's avatar
Michael Albinus committed
1009 1010 1011 1012 1013 1014
desktop-basefilename, desktop-buffer-handlers, desktop-buffer-misc-functions,
desktop-buffer-modes-to-save, desktop-enable, desktop-load-default,
dired-omit-files-p, disabled-command-hook, dungeon-mode-map,
electric-nroff-mode, electric-nroff-newline, electric-perl-terminator,
focus-frame, forward-text-line, generic-define-mswindows-modes,
generic-define-unix-modes, generic-font-lock-defaults, goto-address-at-mouse,
1015 1016 1017 1018
highlight-changes-colours, ibuffer-elide-long-columns, ibuffer-hooks,
ibuffer-mode-hooks, icalendar-convert-diary-to-ical,
icalendar-extract-ical-from-buffer, imenu-always-use-completion-buffer-p,
ipconfig-program, ipconfig-program-options, isearch-lazy-highlight-cleanup,
Michael Albinus's avatar
Michael Albinus committed
1019 1020 1021 1022 1023 1024 1025
isearch-lazy-highlight-initial-delay, isearch-lazy-highlight-interval,
isearch-lazy-highlight-max-at-a-time, iswitchb-use-fonts,
latin1-char-displayable-p, mouse-wheel-click-button, mouse-wheel-down-button,
mouse-wheel-up-button, new-frame, pascal-outline, process-kill-without-query,
recentf-menu-append-commands-p, rmail-pop-password,
rmail-pop-password-required, savehist-load, set-default-font,
spam-list-of-processors, speedbar-add-ignored-path-regexp,
1026 1027 1028
speedbar-buffers-line-path, speedbar-ignored-path-expressions,
speedbar-ignored-path-regexp, speedbar-line-path, speedbar-path-line,
timer-set-time-with-usecs, tooltip-gud-display, tooltip-gud-modes,
1029
tooltip-gud-toggle-dereference, unfocus-frame, unload-hook-features-list,
1030 1031 1032
update-autoloads-from-directories, vc-comment-ring, vc-comment-ring-index,
vc-comment-search-forward, vc-comment-search-reverse, vc-comment-to-change-log,
vc-diff-switches-list, vc-next-comment, vc-previous-comment, view-todo,
Michael Albinus's avatar
Michael Albinus committed
1033 1034 1035 1036 1037 1038 1039
x-lost-selection-hooks, x-sent-selection-hooks.

---
** Further functions and variables obsolete since Emacs 24 have been removed:
default-directory-alist, dired-default-directory,
dired-default-directory-alist, dired-enable-local-variables,
dired-hack-local-variables, dired-local-variables-file, dired-omit-here-always.
1040

1041
** Garbage collection no longer treats miscellaneous objects specially;
1042 1043 1044 1045
they are now allocated like any other pseudovector.  As a result, the
'garbage-collect' and 'memory-use-count' functions no longer return a
'misc' component, and the 'misc-objects-consed' variable has been
removed.
1046

1047

1048
* Lisp Changes in Emacs 27.1
Philipp Stephani's avatar
Philipp Stephani committed
1049

1050
** 'lookup-key' can take a list of keymaps as argument.
1051

1052 1053 1054
+++
** 'condition-case' now accepts 't' to match any error symbol.

1055 1056 1057
+++
** New function 'proper-list-p'.
Given a proper list as argument, this predicate returns its length;
1058 1059
otherwise, it returns nil.  'format-proper-list-p' is now an obsolete
alias for the new function.
1060

Tom Tromey's avatar
Tom Tromey committed
1061
+++
1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073
** Emacs Lisp integers can now be of arbitrary size.
Emacs uses the GNU Multiple Precision (GMP) library to support
integers whose size is too large to support natively.  The integers
supported natively are known as "fixnums", while the larger ones are
"bignums".  The new predicates 'bignump' and 'fixnump' can be used to
distinguish between these two types of integers.

All the arithmetic, comparison, and logical (a.k.a. "bitwise")
operations where bignums make sense now support both fixnums and
bignums.  However, note that unlike fixnums, bignums will not compare
equal with 'eq', you must use 'eql' instead.  (Numerical comparison
with '=' works on both, of course.)
Tom Tromey's avatar
Tom Tromey committed
1074

1075 1076 1077 1078 1079
Since large bignums consume a lot of memory, Emacs limits the size of
the largest bignum a Lisp program is allowed to create.  The
nonnegative value of the new variable 'integer-width' specifies the
maximum number of bits allowed in a bignum.  Emacs signals an integer
overflow error if this limit is exceeded.
1080

1081 1082 1083
Several primitive functions formerly returned floats or lists of
integers to represent integers that did not fit into fixnums.  These
functions now simply return integers instead.  Affected functions
1084 1085 1086 1087
include functions like 'encode-char' that compute code-points, functions
like 'file-attributes' that compute file sizes and other attributes,
functions like 'process-id' that compute process IDs, and functions like
'user-uid' and 'group-gid' that compute user and group IDs.
1088

1089 1090 1091 1092 1093
+++
** Although the default timestamp format is still (HI LO US PS),
it is planned to change in a future Emacs version, to exploit bignums.
The documentation has been updated to mention that the timestamp
format may change and that programs should use functions like
1094 1095 1096
'format-time-string', 'decode-time', and 'encode-time' rather than
probing the innards of a timestamp directly, or creating a timestamp
by hand.
1097 1098

+++
1099
** 'encode-time' supports a new API '(encode-time TIME &optional FORM)'.
1100
This can convert decoded times and Lisp time values to Lisp timestamps
1101
of various forms, including a new timestamp form '(TICKS . HZ)', where
1102 1103 1104
TICKS is an integer and HZ is a positive integer denoting a clock
frequency.  The old encode-time API is still supported.

1105 1106 1107 1108 1109 1110
+++
** 'time-add', 'time-subtract', and 'time-less-p' now accept
infinities and NaNs too, and propagate them or return nil like
floating-point operators do.

+++
1111
** New function 'time-equal-p' compares time values for equality.
1112

1113
** 'define-minor-mode' automatically documents the meaning of ARG.
1114

1115
+++
Eli Zaretskii's avatar
Eli Zaretskii committed
1116 1117 1118 1119
** The function 'recenter' now accepts an additional optional argument.
By default, calling 'recenter' will not redraw the frame even if
'recenter-redisplay' is non-nil.  Call 'recenter' with the new second
argument non-nil to force redisplay per 'recenter-redisplay's value.
1120