GNU Emacs NEWS -- history of user-visible changes. Copyright (C) 2017-2019 Free Software Foundation, Inc. See the end of the file for license conditions. Please send Emacs bug reports to 'bug-gnu-emacs@gnu.org'. If possible, use 'M-x report-emacs-bug'. This file is about changes in Emacs version 27. See file HISTORY for a list of GNU Emacs versions and release dates. See files NEWS.26, NEWS.25, ..., NEWS.18, and NEWS.1-17 for changes in older Emacs versions. You can narrow news to a specific version by calling 'view-emacs-news' with a prefix argument or by typing 'C-u C-h C-n'. Temporary note: +++ indicates that all relevant manuals in doc/ have been updated. --- means no change in the manuals is needed. When you add a new item, use the appropriate mark if you are sure it applies, and please also update docstrings as needed. * Installation Changes in Emacs 27.1 ** 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. The new 'configure' option '--without-libgmp' uses mini-gmp even if a suitable libgmp is available. ** Emacs can now use HarfBuzz as its shaping engine. The new configure option '--with-harfbuzz' adds support for the HarfBuzz text shaping engine. It is on by default; use './configure --without-harfbuzz' to build without it. The HarfBuzz text shaping is available via new font backend drivers 'xfthb' and 'ftcrhb' for Xft and Cairo drawings, respectively, and via the 'harfbuzz' backend on MS-Windows. The Harfbuzz text shaping is preferred to the previously supported ones, so the font backends that use older shaping engines (FLT on GNU and Unix systems and Uniscribe on MS-Windows) are not enabled by default; they can be enabled via the 'font-backend' frame parameter or via X resources. ** The new configure option '--with-json' adds support for JSON using the Jansson library. It is on by default; use './configure --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. ** The configure option '--with-cairo' is no longer experimental. This builds Emacs with Cairo drawing, and supports built-in printing when Emacs is built with GTK+. ** Emacs no longer defaults to using ImageMagick to display images, due to security and stability concerns. To override the default, use 'configure --with-imagemagick'. ** Several configure options now accept an option-argument 'ifavailable'. For example, './configure --with-xpm=ifavailable' now configures Emacs to attempt to use libxpm but to continue building even if libxpm is absent. The other affected options are '--with-gif', '--with-gnutls', '--with-jpeg', '--with-png', and '--with-tiff'. ** 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. ** Emacs has been ported to the '-fcheck-pointer-bounds' option of GCC. 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. ** 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 catch typos and supports '-fcheck-pointer-bounds'. The 'configure' option '--enable-check-lisp-object-type' is therefore no longer as useful and so is no longer enabled by default in developer builds, to reduce differences between developer and production builds. +++ ** Emacs now uses a "portable dumper" instead of unexec. This improves compatibility with memory allocation on modern systems, and in particular better supports the Address Space Layout Randomization (ASLR) feature, a security technique used by most modern operating systems. When built with the portable dumping support (which is the default), Emacs looks for the 'emacs.pdmp' file, generated during the build, in its data directory at startup, and loads the dumped state from there. The new command-line argument '--dump-file=FILE' allows to specify a non-default '.pdmp' file to load the state from; see the node "Initial Options" in the Emacs manual for more information. An Emacs started via a dump file can create a new dump file only if it was invoked with the '-batch' option. Although the portable dumper has been tested, it may have a bug on unusual platforms. If you require traditional unexec dumping you can use the configure-time option '--with-dumping=unexec'; however, please file a bug report describing the situation, as unexec dumping is deprecated. +++ ** The new configure option '--enable-checking=structs' attempts to check that the portable dumper code has been updated to match the last change to one of the data structures that it relies on. +++ ** The configure options '--enable-checking=conslist' and '--enable-checking=xmallocoverrun' have been withdrawn. The former made Emacs irredeemably slow, and the latter made it crash. Neither option was useful with modern debugging tools such as AddressSanitizer. (See etc/DEBUG for the details of using the modern replacements of the removed configure options.) +++ ** The distribution tarball now has test cases; 'make check' runs them. This is intended mostly to help developers. --- ** Emacs now requires GTK 2.24 and GTK 3.10 for the GTK 2 and GTK 3 builds respectively. ** New make target 'help' shows a summary of common make targets. * Startup Changes in Emacs 27.1 +++ ** Emacs now uses the XDG convention for init files. For example, it looks for init.el in ~/.config/emacs/init.el, and similarly for other init files. The XDG_CONFIG_HOME environment variable (which defaults to ~/.config) specifies the parent directory of these and other configuration files, and will override their traditional locations (the home directory, ~/.emacs.d, etc.). Emacs will still look for init files in their traditional locations if XDG_CONFIG_HOME does not exist, so invoking Emacs with XDG_CONFIG_HOME='/nowhere' might be useful if your new-location init files are scrambled, or if you want to force Emacs to ignore files under XDG_CONFIG_HOME for some other reason. +++ ** 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). 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. +++ ** Installed packages are now activated *before* loading the init file. 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' 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. - You can use the new 'package-quickstart' so activation of packages does not need to pay attention to 'package-load-list' or 'package-user-dir' any more. --- ** 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 emacs.service file to eg "~/.config/systemd/user/", you will need to copy the new version of the file again.) * Changes in Emacs 27.1 ** emacsclient +++ *** emacsclient now supports an 'EMACS_SOCKET_NAME' environment variable. The command-line argument '--socket-name' overrides it. (The same behavior as for the pre-existing 'EMACS_SERVER_FILE' variable.) +++ *** Emacs and emacsclient now default to "$XDG_RUNTIME_DIR/emacs" as the directory for client/server sockets, if Emacs is running under an X Window System desktop that sets the 'XDG_RUNTIME_DIR' environment variable to indicate where session sockets should go. To get the old, less-secure behavior, you can set the 'EMACS_SOCKET_NAME' environment variable to an appropriate value. --- *** 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.) ** New function 'network-lookup-address-info'. This does IPv4 and/or IPv6 address lookups on hostnames. --- ** Control of the threshold for using the 'distant-foreground' color. The threshold for color distance below which the 'distant-foreground' color of the face will be used instead of the foreground color can now be controlled via the new variable 'face-near-same-color-threshold'. The default value is 30000, as the previously hard-coded threshold. +++ ** The function 'read-passwd' uses "*" as default character to hide passwords. ** Lexical binding is now used when evaluating interactive Elisp forms. More specifically, lexical-binding is now used for 'M-:', '--eval', as well as in the "*scratch*" and "*ielm*" buffers. --- ** 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. --- ** Show mode line tooltips only if the corresponding action applies. 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. +++ ** 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. +++ ** The functions 'set-frame-height' and 'set-frame-width' are now commands, and will set the currently selected frame to the height/ width specified by the numeric prefix. +++ ** New function 'logcount' calculates an integer's Hamming weight. +++ ** 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. +++ ** 'libxml-parse-xml-region' and 'libxml-parse-html-region' take a parameter that's called DISCARD-COMMENTS, but it really only discards the top-level comment. Therefore this parameter is now obsolete, and the new utility function 'xml-remove-comments' can be used to remove comments before calling the libxml functions to parse the data. +++ ** The Network Security Manager now allows more fine-grained control of what checks to run via the 'network-security-protocol-checks' variable. +++ ** 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. (In addition, several new TLS weaknesses are now warned about.) 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). --- ** New user option 'nsm-trust-local-network'. Allows skipping Network Security Manager checks for hosts on your local subnet(s). It defaults to nil. Usually, there should be no need to set this non-nil, and doing that risks opening your local network connections to attacks. So be sure you know what you are doing before changing the value. +++ ** Native GnuTLS connections can now use client certificates. Previously, this support was only available when using the external 'gnutls-cli' command. Call 'open-network-stream' with ':client-certificate t' to trigger looking up of per-server certificates via 'auth-source'. +++ ** 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. +++ ** 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\} --- ** The German prefix and postfix input methods now support Capital sharp S. --- ** New input methods 'hawaiian-postfix' and 'hawaiian-prefix'. --- ** New input methods 'georgian-qwerty' and 'georgian-nuskhuri'. --- ** New input methods for several variants of the Sami language. The Sami input methods include: 'norwegian-sami-prefix', 'bergsland-hasselbrink-sami-prefix', 'southern-sami-prefix', 'ume-sami-prefix', 'northern-sami-prefix', 'inari-sami-prefix', 'skolt-sami-prefix', and 'kildin-sami-prefix'. +++ ** In Japanese environments that do not specify encodings and are not based on MS-Windows, the default encoding is now utf-8 instead of japanese-iso-8bit. +++ ** 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. +++ ** The function 'executable-find' supports an optional argument REMOTE. This triggers to search the program on the remote host as indicated by 'default-directory'. +++ ** New variable 'auto-save-no-message'. When set to t, no message will be shown when auto-saving (default value: nil). --- ** 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. +++ ** New variable 'emacs-repository-branch'. It reports the git branch from which Emacs was built. +++ ** New user option 'switch-to-buffer-obey-display-actions'. When non-nil, 'switch-to-buffer' uses 'pop-to-buffer-same-window' that respects display actions specified by 'display-buffer-alist' and 'display-buffer-overriding-action'. ** New 'flex' completion style An implementation of popular "flex/fuzzy/scatter" completion which matches strings where the pattern appears as a subsequence. Put simply, makes "foo" complete to both "barfoo" and "frodo". Add 'flex' to 'completion-styles' or 'completion-category-overrides' to use it. ** Connection-local variables +++ *** Connection-local variables are applied by default like file-local and directory-local variables. +++ *** The macro 'with-connection-local-variables' has been renamed from 'with-connection-local-profiles'. No argument PROFILES needed any longer. --- ** New variable 'next-error-verbose' controls when 'next-error' outputs a message about the error locus. --- ** New variable 'grep-search-path' defines the directories searched for grep hits (this used to be controlled by 'compilation-search-path'). --- ** New variable 'emacs-lisp-compilation-search-path' defines the directories searched for byte-compiler error messages (this used to be controlled by 'compilation-search-path'). ** Multicolor fonts such as "Noto Color Emoji" can be displayed on Emacs configured with Cairo drawing and linked with cairo >= 1.16.0. +++ ** Emacs now optionally displays a fill column indicator. This is similar to what 'fill-column-indicator' package provides, but much faster and compatible with 'show-trailing-whitespace'. Customize the buffer-local variables 'display-fill-column-indicator' and 'display-fill-column-indicator-character' to activate the indicator. The indicator is not displayed at all in minibuffer windows and in tooltips, as it is not useful there. There are 2 new buffer local variables and 1 face to customize this mode they are described in the manual "(emacs) Display". +++ ** 'progress-reporter-update' accepts a suffix string to display. --- ** New variable 'xref-file-name-display' controls the display of file names in xref buffers. ** New customizable variable 'byte-count-to-string-function'. It is used for displaying file sizes and disk space in some cases. +++ ** Emacs now interprets RGB triplets like HTML, SVG, and CSS do. The X convention previously used differed slightly, particularly for RGB triplets with a single hexadecimal digit per component. --- ** The toolbar now shows the equivalent key binding in its tooltips. * Editing Changes in Emacs 27.1 --- ** The 'newline-and-indent' command (commonly bound to 'RET' in many modes) now takes an optional numeric argument to specify how many times is should insert newlines (and indent). +++ ** New command 'make-empty-file'. --- ** 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). +++ ** 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 typographic quotes, “like this”, in text modes, and in comments in non-text modes. --- ** 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. --- ** 'write-abbrev-file' now includes special properties. 'write-abbrev-file' now writes special properties like ':case-fixed' for abbrevs that have them. +++ ** '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. +++ ** The new functions and commands 'text-property-search-forward' and 'text-property-search-backward' have been added. These provide an interface that's more like functions like 'search-forward'. --- ** More commands support noncontiguous rectangular regions, namely 'upcase-dwim', 'downcase-dwim', 'capitalize-dwim', 'capitalize-region', 'upcase-initials-region', 'replace-string', 'replace-regexp', and 'delimit-columns-region'. +++ ** 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. --- ** '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. +++ ** Network connections using 'local' can now use IPv6. 'make-network-process' now uses the correct loopback address when asked to use ':host 'local' and ':family 'ipv6'. +++ ** The new function 'replace-region-contents' replaces the current region using a given replacement-function in a non-destructive manner (in terms of 'replace-buffer-contents'). +++ ** The command 'replace-buffer-contents' now has two optional arguments mitigating performance issues when operating on huge buffers. +++ ** The command 'delete-indentation' now operates on the active region. If the region is active, the command joins all the lines in the region. When there's no active region, the command works on the current and the previous or the next line, as before. * Changes in Specialized Modes and Packages in Emacs 27.1 --- ** 'autoconf-mode' is now used instead of 'm4-mode' for the acinclude.m4/aclocal.m4/acsite.m4 files. --- ** On GNU/Linux, 'M-x battery' will now list all batteries, no matter what they're named, and the 'battery-linux-sysfs-regexp' variable has been removed. ** The 'list-processes' command now includes port numbers in the network connection information (in addition to the host name). ** The 'cl' package is now officially deprecated in favor of 'cl-lib'. +++ ** winner *** A new variable, 'winner-boring-buffers-regexp', has been added. ** table ** 'table-generate-source' and friends now support outputting wiki and mediawiki format tables. --- ** telnet-mode *** Reverting a buffer in 'telnet-mode' will restart a closed connection. ** goto-addr *** A way to more conveniently specify what URI address schemes that should be ignored have been added via the 'goto-address-uri-schemes-ignored' variable. +++ ** tex-mode *** 'latex-noindent-commands' controls indentation of certain commands. You can use this new variable to control indentation of arguments of \emph, \footnote, and similar commands. ** byte compiler *** 'byte-compile-dynamic' is now obsolete. This is because on the one hand it suffers from various misbehaviors in corner cases that have plagued it for years, and on the other experiments indicated that it doesn't bring any measurable benefit. ** compile.el --- *** In 'compilation-error-regexp-alist', 'line' (and 'end-line') can be functions. +++ *** 'compilation-context-lines' can now take the value t; this is like nil, but instead of scrolling the current line to the top of the screen when there is no left fringe, it inserts a visible arrow before column zero. ** cl-lib.el +++ *** 'cl-defstruct' has a new ':noinline' argument to prevent inlining its functions. +++ *** 'cl-defstruct' slots accept a ':documentation' property --- *** 'cl-values-list' will now signal an error if its argument isn't a list. ** doc-view.el *** New commands 'doc-view-presentation' and 'doc-view-fit-window-to-page'. *** Added support for password-protected PDF files ** Ido *** New user option 'ido-big-directories' to mark directories whose names match certain regular expressions as big. Ido won't attempt to list the contents of such directories when completing file names. ** Minibuffer --- *** Minibuffer now uses 'minibuffer-message' to display error messages at the end of the active minibuffer. ** map.el *** Now also understands plists. *** Now defined via generic functions that can be extended via 'cl-defmethod'. *** Deprecate the 'map-put' macro in favor of a new 'map-put!' function. *** 'map-contains-key' now returns a boolean rather than the key. *** Deprecate the 'testfn' args of 'map-elt' and 'map-contains-key'. *** New generic function 'map-insert'. +++ ** seq.el New convenience functions 'seq-first' and 'seq-rest' give easy access to respectively the first and all but the first elements of sequences. The new predicate function 'seq-contains-p' should be used instead of the now obsolete 'seq-contains'. --- ** 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. +++ ** New variable 'warning-fill-column' for 'display-warning'. ** Windmove *** 'windmove-create-window' when non-nil makes a new window on moving off the edge of the frame. *** Windmove supports directional window display and selection. The new command 'windmove-display-default-keybindings' binds default keys with provided modifiers (by default, Shift-Meta) to the commands that display the next buffer in the window at the specified direction. This is like 'windmove-default-keybindings' that binds keys to commands that select the window in the specified direction, but additionally it displays the buffer from the next command in that window. For example, 'S-M-right C-h i' displays the "*Info*" buffer in the right window, creating the window if necessary. A special key can be customized to display the buffer in the same window, for example, 'S-M-0 C-h e' displays the "*Messages*" buffer in the same window. *** Windmove also supports directional window deletion. The new command 'windmove-delete-default-keybindings' binds default keys with provided prefix (by default, 'C-x') and modifiers (by default, 'Shift') to the commands that delete the window in the specified direction. For example, 'C-x S-down' deletes the window below. With a prefix arg 'C-u', also kills the buffer in that window. With 'M-0', deletes the selected window and selects the window that was in the specified direction. *** New command 'windmove-swap-states-in-direction' binds default keys to the commands that swap the states of the selected window with the window in the specified direction. ** Octave mode The mode is automatically enabled in files that start with the 'function' keyword. ** project.el *** New commands 'project-search' and 'project-query-replace-regexp'. *** New customizable variable 'project-read-file-name-function'. ** Etags +++ *** 'next-file' is now an obsolete alias of 'tags-next-file'. *** 'tags-loop-revert-buffers' is an obsolete alias of 'fileloop-revert-buffers'. *** The 'tags-loop-continue' function along with the 'tags-loop-operate' and 'tags-loop-scan' variables are now obsolete; use the new 'fileloop-initialize' and 'fileloop-continue' functions instead. +++ *** etags is now able to read Zstandard-compressed files. ** bibtex --- *** New commands 'bibtex-next-entry' and 'bibtex-previous-entry'. In 'bibtex-mode-map', 'forward-paragraph' and 'backward-paragraph' are remapped to these, respectively. ** Dired +++ *** New command 'dired-create-empty-file'. +++ *** New command and keystroke 'dired-number-of-marked-files' bound to '* N'. *** The marking commands now report how many files were marked by the command itself, not how many files are marked in total. --- *** A new face, 'dired-special', is used to highlight sockets, named pipes, block devices and character devices. ** Find-Dired *** New customizable variable 'find-dired-refine-function'. The default value is 'find-dired-sort-by-filename'. *** New sorting options for the variable 'find-ls-option'. --- *** Zstandard compression is now supported for 'dired-do-compress' and 'dired-do-compress-to'. ** Change Logs and VC +++ *** New command 'log-edit-generate-changelog-from-diff', bound to C-c C-w. This generates ChangeLog entries from the VC fileset diff. *** 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. *** New customizable variable 'vc-find-revision-no-save'. With non-nil, 'vc-find-revision' doesn't write the created buffer to file. --- *** 'vc-dir-ignore' now takes a prefix argument to ignore all marked files. *** 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. *** 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. *** The new hook 'vc-retrieve-tag-hook' runs after retrieving a tag. --- *** 'vc-hg' now invokes 'smerge-mode' when visiting files. Code that attempted to invoke 'smerge-mode' when visiting an Hg file with conflicts existed in earlier versions of Emacs, but incorrectly never detected a conflict due to invalid assumptions about cached values. +++ *** 'C-u C-x v D' ('vc-root-version-diff') prompts for two revisions and compares their entire trees. *** New user option 'vc-hg-revert-switches' specifies switches to pass to Hg revert. *** 'C-x v M D' ('vc-diff-mergebase') and 'C-x v M L' ('vc-log-mergebase') print diffs and logs between the merge base (common ancestor) of two given revisions. +++ *** The new 'd' command ('vc-dir-clean-files') in 'vc-dir-mode' buffers will delete the marked files (or if no files are marked, the file under point). This command does not notify the VC backend, and is mostly useful for unregistered files. *** New command 'vc-log-search' asks for a pattern, searches it in the revision log, and displays matched log entries in the log buffer. For example, 'M-x vc-log-search RET bug#36644 RET' displays all entries whose log messages match the bug number. With a prefix argument asks for a command, so for example, 'C-u M-x vc-log-search RET git log -1 f302475 RET' will display just one log entry found by its revision number. *** 'C-x v =' can now mimic Magit's diff format. Set the new user option 'diff-font-lock-prettify' to t for that, see below under "Diff mode". ** Diff mode +++ *** Hunks are now automatically refined by font-lock. To disable refinement, set the new user option 'diff-refine' to nil. To get back the old behavior where hunks are refined as you navigate through a diff, set 'diff-refine' to the symbol 'navigate'. +++ *** 'diff-auto-refine-mode' is deprecated in favor of 'diff-refine'. It is no longer enabled by default and binding it no longer has any effect. +++ *** Better syntax highlighting of Diff hunks. Fragments of source in Diff hunks are now by default highlighted according to the appropriate major mode. Customize the new option 'diff-font-lock-syntax' to nil to disable this. *** File headers can be shortened, mimicking Magit's diff format. To enable it, set the new user option 'diff-font-lock-prettify' to t. On GUI frames, this option also displays the insertion and deletion indicators on the left fringe. +++ *** 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. ** Texinfo +++ *** New function for inserting '@pxref', '@xref', or '@ref' commands. The function 'texinfo-insert-dwim-@ref', bound to 'C-c C-c r' by default, inserts one of three types of references based on the text surrounding point, namely '@pxref' near a parenthesis, '@xref' at the start of a sentence or at '(point-min)', else '@ref'. ** Browse-url *** 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. *** A new function, 'browse-url-add-buttons' can be used to add clickable links to most ordinary special-mode buffers that display text that have URLs embedded. 'browse-url-button-regexp' controls what's considered a button. *** A new variable, 'browse-url-secondary-browser-function', has been added. ** Comint +++ *** 'send-invisible' is now an obsolete alias for 'comint-send-invisible'. Also, 'shell-strip-ctrl-m' is declared obsolete. +++ *** '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. +++ *** 'comint-run' can now accept a list of switches to pass to the program. 'C-u M-x comint-run' will prompt for the switches interactively. ** SQL *** SQL Indent Minor Mode SQL Mode now supports the ELPA 'sql-indent' package for assisting sophisticated SQL indenting rules. Note, however, that 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. The 'sql-indent' package from ELPA must be installed to get the 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 you have existing customizations to these variables, you should make sure that the new default entry is included. *** Connection Wallet Database passwords can now by stored in NETRC or JSON data files that may optionally be encrypted. When establishing an interactive session with the database via 'sql-connect' or a product specific function, like 'sql-mysql' or 'my-postgres', the password wallet will be searched for the password. The 'sql-product', 'sql-server', 'sql-database', and the 'sql-username' will be used to identify the appropriate authorization. This eliminates the discouraged practice of embedding database passwords in your Emacs initialization. See the 'auth-source' module for complete documentation on the file formats. By default, the wallet file is expected to be in the 'user-emacs-directory', named 'sql-wallet' or '.sql-wallet', with '.json' (JSON) or no (NETRC) suffix. Both file formats can optionally be encrypted with GPG by adding an additional '.gpg' suffix. ** Term --- *** 'term-read-noecho' is now obsolete, use 'read-passwd' instead. +++ *** 'serial-term' now takes an optional parameter to leave the emulator in line mode. ** Flymake +++ *** The variable 'flymake-diagnostic-types-alist' is obsolete. You should instead set properties on known diagnostic symbols, like ':error' and ':warning', as demonstrated in the Flymake manual. *** New customizable variable 'flymake-start-on-save-buffer'. Control whether Flymake starts checking the buffer on save. *** Flymake and backend functions may exchange hints about buffer changes. This enables more efficient backends. See the docstring of 'flymake-diagnostic-functions' or the Flymake manual for details. +++ *** 'flymake-start-syntax-check-on-newline' is now obsolete, use 'post-self-insert-hook' to check on newline. ** Ruby *** The Rubocop Flymake diagnostic function will only run Lint cops if it can't find the config file. *** Rubocop is called with 'bundle exec' if Gemfile mentions it. *** New command 'ruby-find-library-file' bound to 'C-c C-f'. ** Package *** Change of 'package-check-signature' for packages with multiple sigs In previous Emacsen, 't' checked that all signatures are valid. Now 't' only checks that at least one signature is valid and the new 'all' value needs to be used if you want to enforce that all signatures are valid. This only affects packages with multiple signatures. +++ *** The meaning of 'allow-unsigned' in 'package-check-signature' has changed slightly: If a usable OpenPGP configuration can't be found (for instance, if gpg isn't installed), it now has the same meaning as nil. *** New function 'package-get-version' lets packages query their own version. Example use in auctex.el: '(defconst auctex-version (package-get-version))' *** New 'package-quickstart' feature. 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'. --- *** Imenu support has been added to 'package-menu-mode'. ** Info +++ *** Clicking on the left/right arrow icon in the Info tool-bar while holding down the Ctrl key pops up a menu of previously visited Info nodes where you can select a node to go back (like in browsers). --- *** 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. ** 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. +++ *** 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. --- *** 'xref-find-definitions' now sets the mark at the buffer position where it was invoked. --- *** New xref faces 'xref-file-header', 'xref-line-number', 'xref-match'. *** New variable 'xref-show-definitions-function'. It encapsulates the logic pertinent to showing the result of 'xref-find-definitions'. The user can change it to customize its behavior and the display of results. *** Search results show the buffer even for one hit. The search-type Xref commands (e.g. 'xref-find-references' or 'project-find-regexp') now show the results buffer even when there is only one hit. This can be altered by changing 'xref-show-xrefs-function'. *** Xref buffers support refreshing the search results. A new command 'xref-revert-buffer' is bound to 'g'. --- *** Imenu support has been added to 'xref--xref-buffer-mode'. ** Ecomplete *** The ecomplete sorting has changed to a decay-based algorithm. This can be controlled by the new 'ecomplete-sort-predicate' variable. *** The 'ecompleterc' file is now placed in '~/.emacs.d/ecompleterc' by default. Of course it will still find it if you have it in '~/.ecompleterc'. ** Gnus +++ *** New option 'gnus-use-atomic-windows' makes Gnus window layouts atomic. See the "Atomic Windows" section of the Elisp manual for details. +++ *** There's a new value for 'gnus-article-date-headers', 'combined-local-lapsed', which will show both the time (in the local timezone) and the lapsed time. --- *** Gnus now maps imaps to 993 only on old MS-Windows versions. The nnimap backend used to do this unconditionally to work around problems on old versions of MS-Windows. This is now done only for Windows XP and older. +++ *** 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. +++ *** A prefix argument to 'gnus-summary-limit-to-score' will limit reverse. Limit to articles with score at below. *** The function 'gnus-score-find-favorite-words' has been renamed from 'gnus-score-find-favourite-words'. --- *** Gmane has been removed as an nnir backend, since Gmane no longer has a search engine. +++ *** Splitting mail on common mailing list headers has been added. See the concept index in the Gnus manual for the 'match-list' entry. +++ *** nil is no longer an allowed value for 'mm-text-html-renderer'. +++ The default value of 'mm-inline-large-images' has changed from nil to 'resize', which means that large images will be resized instead of displayed with an external program by default. +++ *** A new Gnus summary mode command, 'S A' ('gnus-summary-attach-article') can be used to attach the current article(s) to a pre-existing Message buffer, or create a new Message buffer with the article(s) attached. +++ *** A new Gnus summary mode command, 'w' ('gnus-summary-browse-url') scans the article buffer for URLs, and offers them to the user to open with 'browse-url'. --- *** 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'. --- +++ The buttons in the Gnus article buffer were formerly widgets (i.e., buttons from widget.el). This has now changed, and they are now buttons (from button.el), and commands like 'TAB' now search for buttons instead of widgets. There should be no user-visible changes, but out-of-tree code that relied on widgets being present might now fail. ** erc --- *** 'erc-button-google-url' has been renamed to 'erc-button-search-url' and its value has been changed to Duck Duck Go. --- *** 'erc-send-pre-hook' and 'erc-send-this' have been obsoleted. The variable to use instead to alter text to be sent is now 'erc-pre-send-functions'. ** EUDC *** XEmacs support has been removed. ** eww/shr +++ *** The new variable 'shr-cookie-policy' can be used to control when to use cookies when fetching embedded images. The default is to use them when the images are from the same domain as the main HTML document. +++ *** The 'eww' command can now create a new EWW buffer. Invoking the command with a prefix argument will cause it to create a new EWW buffer for the URL instead of reusing the default one. +++ *** The 'd' ('eww-download') command now falls back to current page's URL. If this command is invoked with no URL at point, it now downloads the current page instead of signaling an error. *** When opening external links in eww/shr (typically with the '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 has been executed. +++ *** 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. +++ *** 'shr-external-browser' has been made into an obsolete alias of 'browse-url-secondary-browser-function'. --- *** 'shr-tag-ol' now respects the ordered list 'start' attribute. --- *** The following tags are now handled: '', '', and ''. ** Htmlfontify *** 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'. +++ ** 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. ** Smtpmail *** Authentication mechanisms can be added via external packages, by defining new 'cl-defmethod' of 'smtpmail-try-auth-method'. *** To always force smtpmail to send credentials over on the first attempt when communicating with the SMTP server(s), the 'smtpmail-servers-requiring-authorization' variable can be used. +++ *** smtpmail will now try resending mail when getting a transient 4xx error message from the SMTP server. The new 'smtpmail-retries' variable says how many times to retry. ** Footnote mode *** Support Hebrew-style footnotes *** Footnote text lines are now aligned. Can be controlled via the new variable 'footnote-align-to-fn-text'. ** 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'. --- *** CSS mode, SCSS mode, and Less CSS mode now have support for Imenu. ** SGML mode --- *** 'sgml-quote' now handles double quotes and apostrophes when escaping text and in addition all numeric entities when unescaping text. ** 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. ** 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. ** Help --- *** Description of variables and functions give an estimated first release. --- *** 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'. --- *** The list of help commands produced by 'C-h C-h' ('help-for-help') can now be searched via 'C-s'. ** Ibuffer --- *** New filter 'ibuffer-filter-by-process'; bound to '/E'. --- *** 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. ** Search and Replace *** Isearch supports a prefix argument for 'C-s' ('isearch-repeat-forward') and 'C-r' ('isearch-repeat-backward'). With a prefix argument, these commands repeat the search for the specified occurrence of the search string. A negative argument repeats the search in the opposite direction. This makes possible also to use a prefix argument for 'M-s .' ('isearch-forward-symbol-at-point') to find the next Nth symbol. *** To go to the first/last occurrence of the current search string is possible now with new commands 'isearch-beginning-of-buffer' and 'isearch-end-of-buffer' bound to 'M-s M-<' and 'M-s M->' in Isearch. With a numeric argument, they go to the Nth absolute occurrence counting from the beginning/end of the buffer. This complements 'C-s'/'C-r' that searches for the next Nth relative occurrence with a numeric argument. *** '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. *** '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. +++ *** New isearch bindings. 'C-M-z' invokes new function 'isearch-yank-until-char', which yanks everything from point up to but not including the specified character into the search string. This is especially useful for keyboard macros. 'C-M-w' in isearch changed from 'isearch-del-char' to the new function 'isearch-yank-symbol-or-char'. 'isearch-del-char' is now bound to 'C-M-d'. +++ 'M-s h l' invokes 'highlight-lines-matching-regexp' using the search string to highlight lines matching the search string. This is similar to the existing binding 'M-s h r' ('highlight-regexp') that highlights JUST the search string. +++ *** New variable 'isearch-yank-on-move' provides options 't' and 'shift' to extend the search string by yanking text that ends at the new position after moving point in the current buffer. 'shift' extends the search string by motion commands while holding down the shift key. *** 'isearch-allow-scroll' provides new option 'unlimited' to allow scrolling any distance off screen. --- *** Isearch now remembers the regexp-based search mode for words/symbols and case-sensitivity together with search strings in the search ring. --- *** Isearch now has its own tool-bar and menu-bar menu. +++ *** 'flush-lines' prints and returns the number of deleted matching lines. --- *** 'char-fold-to-regexp' now matches more variants of a base character. The table used to check for equivalence of characters is now built using the complete chain of unicode decompositions of a character, rather than stopping after one level, such that searching for e.g. "GREEK SMALL LETTER IOTA" will now also find "GREEK SMALL LETTER IOTA WITH OXIA". +++ *** New char-folding options: 'char-fold-include' lets you add ad hoc foldings, 'char-fold-exclude' to remove foldings from default decomposition, and 'char-fold-symmetric' to search for any of an equivalence class of characters. For example, with a 'nil' value of 'char-fold-symmetric' you can search for "e" to find "é", but not vice versa. With a non-nil value you can search for either, for example, you can search for "é" to find "e". ** Debugger +++ *** The Lisp Debugger is now based on 'backtrace-mode'. Backtrace mode adds fontification and commands for changing the appearance of backtrace frames. See the node "(elisp) Backtraces" in the Elisp manual for documentation of the new mode and its commands. ** Edebug +++ *** The runtime behavior of Edebug's instrumentation can be changed using the new variables 'edebug-behavior-alist', 'edebug-after-instrumentation-function' and 'edebug-new-definition-function'. Edebug's behavior can be changed globally or for individual definitions. +++ *** Edebug's backtrace buffer now uses 'backtrace-mode'. Backtrace mode adds fontification, links and commands for changing the appearance of backtrace frames. See the node "(elisp) Backtraces" in the Elisp manual for documentation of the new mode and its commands. 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. ** Enhanced xterm support *** New variable 'xterm-set-window-title' controls whether Emacs sets the XTerm window title. This feature is experimental and is disabled by default. ** Grep +++ *** 'rgrep', 'lgrep' and 'zrgrep' now hide part of the command line that contains a list of ignored directories and files. 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. *** 'grep-find-use-xargs' is now customizable with sorting options. ** ERT +++ *** New variable 'ert-quiet' allows to make ERT output in batch mode less verbose by removing non-essential information. +++ *** ERT's backtrace buffer now uses 'backtrace-mode'. Backtrace mode adds fontification and commands for changing the appearance of backtrace frames. See the node "(elisp) Backtraces" in the Elisp manual for documentation of the new mode and its commands. ** Gamegrid --- *** Gamegrid now determines its default glyph size based on display dimensions, instead of always using 16 pixels. As a result, Tetris, Snake and Pong are more playable on HiDPI displays. --- *** 'gamegrid-add-score' can now sort scores from lower to higher. This is useful for games where lower scores are better, like time-based games. ** Filecache --- *** Completing filenames in the minibuffer via 'C-TAB' now uses the styles as configured by the variable 'completion-styles'. ** New macros 'thunk-let' and 'thunk-let*'. These macros are analogue to 'let' and 'let*', but create bindings that are evaluated lazily. ** next-error +++ *** New customizable variable 'next-error-find-buffer-function'. 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'. ** nxml-mode --- *** The default value of 'nxml-sexp-element-flag' is now t. This means that pressing 'C-M-SPACE' now selects the entire tree by default, and not just the opening element. ** Eshell *** TAB completion uses the standard 'completion-at-point' rather than 'pcomplete'. Its UI is slightly different but can be customized to behave similarly, e.g. Pcomplete's default cycling can be obtained with '(setq completion-cycle-threshold 5)'. --- *** Eshell no longer re-initializes its keymap every call. This allows users to use (define-key eshell-mode-map ...) as usual. Some modules have their own minor mode now to account for these changes. +++ *** 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) --- *** The function 'eshell-uniquify-list' has been renamed from 'eshell-uniqify-list'. *** 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 process. It now accepts signals specified either by name or by its number. --- *** Emacs now follows symlinks in history-related files. The files specified by 'eshell-history-file-name' and 'eshell-last-dir-ring-file-name' can include symlinks; these are now followed when Emacs writes the relevant history variables to the disk. ** Shell --- *** Program name completion inside remote shells works now as expected. +++ *** The variable 'shell-file-name' can be set now as connection-local variable for remote shells. It still defaults to "/bin/sh". ** Single shell commands +++ *** 'async-shell-command-width' defines the number of display columns available for output of asynchronous shell commands. ** Pcomplete *** The function 'pcomplete-uniquify-list' has been renamed from 'pcomplete-uniqify-list'. --- *** 'pcomplete/make' now completes on targets in included files, recursively. To recover the previous behavior, set new user option 'pcmpl-gnu-makefile-includes' to nil. ** Auth-source --- *** The Secret Service backend supports the ':create' key now. *** .authinfo and .netrc files now use a new mode: 'authinfo-mode'. This is just like 'fundamental-mode', except that it hides passwords under a "****" display property. When the cursor moves to this text, the real password is revealed (via 'reveal-mode'). The 'authinfo-hidden' variable can be used to control what to hide. ** Tramp +++ *** New connection method "nextcloud", which allows to access OwnCloud or NextCloud hosted files and directories. +++ *** New connection method "rclone", which allows to access system storages via the 'rclone' program. This feature is experimental. +++ *** New connection method "sudoedit", which allows to edit local files with different user credentials. Contrary to the "sudo" method, no session is run permanently in the background. This is for security reasons. +++ *** Connection methods "obex" and "synce" are removed, because they are obsoleted in GVFS. +++ *** Validated passwords are saved by auth-source backends which support this. +++ *** During user and host name completion in the minibuffer, results from auth-source search are taken into account. This can be disabled by setting the user option 'tramp-completion-use-auth-sources' to nil. +++ *** The user option 'tramp-ignored-file-name-regexp' allows to disable Tramp for some look-alike remote file names. +++ *** For some connection methods, like "su" or "sudo", the host name in ad-hoc multi-hop file names must match the previous hop. Default host names are adjusted to the host name from the previous hop. +++ *** For the connection methods "sudo" and "doas" there exists a timeout, after which the underlying session is disabled. This is for security reasons. +++ *** For some connection methods, like "sshx" or "plink", it is possible to configure the remote login shell. This avoids problems with remote hosts, where "/bin/sh" is a link to a shell which cooperates badly with Tramp. ** 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. --- *** The default '/quit' and '/part' reasons are now configurable. Two new user options are provided for this: 'rcirc-default-part-reason' and 'rcirc-default-quit-reason'. ** Register --- *** The return value of method 'register-val-describe' includes the names of buffers shown by the windows of a window configuration. --- ** The options.el library has been removed. It was obsolete since Emacs 22.1, replaced by customize. ** 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. ** Message *** 'message-mode' now supports highlighting citations of different depths. This can be customized via 'message-cite-level-function' and the new 'message-cited-text-*' faces. +++ *** Messages can now be systematically encrypted when the PGP keyring contains a public key for every recipient. To achieve this, add 'message-sign-encrypt-if-all-keys-available' to 'message-send-hook'. --- *** When replying a message that have addresses on the form '"foo@bar.com" ', Message will elide the repeated "name" from the address field in the response. --- *** The default of 'message-forward-as-mime' has changed from t to nil as it has been reported that many recipients can't read forwards that are formatted as MIME digests. +++ *** 'message-forward-included-headers' has changed its default to exclude most headers when forwarding. *** 'mml-secure-openpgp-sign-with-sender' sets also "gpg --sender" When 'mml-secure-openpgp-sign-with-sender' is non-nil message sender's email address (in addition to its old behaviour) will also be used to set gpg's "--sender email@domain" option. The option is useful for two reasons when verifying the signature: 1. GnuPG's TOFU statistics are updated for the specific user id (email) only. See gpg(1) man page about "--sender". 2. GnuPG's '--auto-key-retrieve' functionality can use WKD (web key directory) method for finding the signer's key. You need GnuPG 2.2.17 to fully benefit from this feature. See gpg(1) man page for '--auto-key-retrieve'. --- ** EasyPG --- *** 'epa-pinentry-mode' is renamed to 'epg-pinentry-mode'. It now applies to epg functions as well as epa functions. --- *** 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. *** 'epg-context' structure supports now 'sender' slot. The value of the new 'sender' slot (if a string) is used to set gpg's '--sender' option. This feature is used by 'mml-secure-openpgp-sign-with-sender'. See gpg(1) manual page about '--sender' for more information. --- ** 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. *** 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. ** 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. +++ *** 'thread-signal' does not propagate errors to the main thread. Instead, error messages are just printed in the main thread. --- *** 'thread-alive-p' is now obsolete, use 'thread-live-p' instead. +++ *** 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'. ** thingatpt.el --- *** 'thing-at-point' supports a new "thing" called 'uuid'. A symbol 'uuid' can be passed to 'thing-at-point' and it returns the UUID at point. --- *** 'number-at-point' will now recognize hex number like 0xAb09 and #xAb09 and return them as numbers. --- *** 'word-at-point' and 'sentence-at-point' accept NO-PROPERTIES. Just like 'thing-at-point' itself. ** Interactive automatic highlighting +++ *** 'highlight-regexp' can now highlight subexpressions. The new command accepts a prefix numeric argument to choose the subexpression. ** Mouse display of minor mode menu --- *** 'minor-mode-menu-from-indicator' now displays full minor mode name. When there is no menu for a mode, display the mode name after the indicator instead of just the indicator (which is sometimes cryptic). ** rx --- *** rx now handles raw bytes in character alternatives correctly, when given in a string. Previously, '(any "\x80-\xff")' would match characters U+0080...U+00FF. Now the expression matches raw bytes in the 128...255 range, as expected. --- *** The rx 'or' and 'seq' forms no longer require any arguments. (or) produces a regexp that never matches anything, while (seq) matches the empty string, each being an identity for the operation. This also works for their aliases: '|' for 'or'; ':', 'and' and 'sequence' for 'seq'. --- *** 'regexp' and new 'literal' accept arbitrary lisp as arguments. In this case, 'rx' will generate code which produces a regexp string at run time, instead of a constant string. ** Frames +++ *** New command 'make-frame-on-monitor' makes a frame on the specified monitor. +++ *** New value of 'minibuffer' frame parameter 'child-frame'. This allows to create and parent immediately a minibuffer-only child frame when making a frame. --- *** New predicates 'display-blink-cursor-p' and 'display-symbol-keys-p'. These predicates are to be preferred over 'display-graphic-p' when testing for blinking cursor capability and the capability to have symbols (e.g., '[return]', '[tab]', '[backspace]') as keys respectively. ** Tabulated List mode +++ *** New user options for tabulated list sort indicators. You can now customize which sorting indicator character to display near the current column in Tabulated Lists (see variables 'tabulated-list-gui-sort-indicator-asc', 'tabulated-list-gui-sort-indicator-desc', 'tabulated-list-tty-sort-indicator-asc', and 'tabulated-list-tty-sort-indicator-desc'). +++ *** Two new commands and keystrokes have been added to the tabulated list mode: 'w' (which widens the current column) and 'c' which makes the current column contract. ** Text mode +++ *** 'text-mode-variant' is now obsolete, use 'derived-mode-p' instead. ** CUA mode --- *** New user option 'cua-rectangle-terminal-modifier-key'. This user option allows for the customization of the modifier key used in a terminal frame. ** JS mode --- *** JSX syntax is now automatically detected and enabled. If a file imports Facebook's 'React' library, or if the file uses the extension '.jsx', then various features supporting XML-like syntax will be supported in 'js-mode' and derivative modes. ('js-jsx-mode' no longer needs to be enabled.) --- *** New user option 'js-jsx-detect-syntax' disables automatic detection. This is turned on by default. --- *** New user option 'js-jsx-syntax' enables JSX syntax unconditionally. This is off by default. --- *** New variable 'js-jsx-regexps' controls JSX detection. --- *** JSX syntax is now highlighted like SGML. --- *** JSX code is properly indented in many more scenarios. Previously, JSX indentation usually only worked when an element was wrapped in parenthesis (e.g. in a 'return' statement or a function call). It would also fail in many intricate cases. Now, indentation should work anywhere without parenthesis; many more intricacies are supported; and, indentation conventions align more closely with those of the React developer community (see 'js-jsx-align->-with-<'), otherwise still adhering to SGML conventions. --- *** New user option 'js-jsx-align->-with-<' controls '>' indents. Commonly in JSX code, a '>' on its own line is indented at the same level as its opening '<'. This is the new default for JSX. This behavior is slightly different than that used by SGML in Emacs, where '>' is indented at the same level as attributes, which was also the old default for JSX. This is turned on by default. To get back the old default indentation behavior of aligning '>' with attributes, set 'js-jsx-align->-with-<' to nil. --- *** Indentation uses 'js-indent-level' instead of 'sgml-basic-offset'. Since JSX is a syntax extension of JavaScript, it makes the most sense for JSX expressions to be indented the same number of spaces as other JS expressions. This is a breaking change, but it probably aligns with how you'd expect this indentation to behave. If you want JSX to be indented like JS, you won't need to change your config. The old behavior can be emulated by controlling JSX indentation independently of JS, by setting 'js-jsx-indent-level'. --- *** New user option 'js-jsx-indent-level' for different JSX indentation. If you wish to indent JSX by a different number of spaces than JS, set this user option to the desired number. --- *** New user option 'js-jsx-attribute-offset' for JSX attribute indents. --- *** New variable 'js-syntactic-mode-name' controls mode name display. Previously, the mode name was simply 'JavaScript'. Now, when a syntax extension like JSX is enabled, the mode name is 'JavaScript[JSX]'. Set this variable to nil to disable the new behavior. --- *** New function 'js-use-syntactic-mode-name' for deriving modes. Packages deriving from 'js-mode' with 'define-derived-mode' should call this function to add enabled syntax extensions to their mode name, too. ** Autorevert *** New variable 'auto-revert-avoid-polling' for saving power. When set to a non-nil value, buffers in Auto Revert mode are no longer polled for changes periodically. This reduces the power consumption of an idle Emacs, but may fail on some network file systems; set 'auto-revert-notify-exclude-dir-regexp' to match files where notification is not supported. The default value is nil. *** New variable 'buffer-auto-revert-by-notification' A major mode can declare that notification on the buffer's default directory is sufficient to know when updates are required, by setting the new variable 'buffer-auto-revert-by-notification' to a non-nil value. Auto Revert mode can use this information to avoid polling the buffer periodically when 'auto-revert-avoid-polling' is non-nil. --- *** 'global-auto-revert-ignore-buffer' can now also be a predicate function that can be used for more fine-grained control of which buffers to auto-revert. ** auth-source-pass +++ *** New customizable variable 'auth-source-pass-filename'. Allows setting the path to the password-store, defaults to "~/.password-store". +++ *** New customizable variable 'auth-source-pass-port-separator'. Specifies separator between host and port, defaults to colon ":". --- *** Minimize the number of decryptions during password lookup. This makes the package usable with physical tokens requiring touching a sensor for every decryption. --- *** 'auth-source-pass-get' is now autoloaded. ** Bookmarks --- *** 'bookmark-file' and 'bookmark-old-default-file' are now obsolete aliases of 'bookmark-default-file'. *** New user option 'bookmark-watch-bookmark-file'. When non-nil, watch whether the bookmark file has changed on disk. --- *** The old bookmark file format is no longer supported. This bookmark file format has not been used in Emacs since at least version 19.34, released in 1996, and will no longer be automatically converted to the new bookmark file format. The following functions are now declared obsolete: bookmark-grok-file-format-version, bookmark-maybe-upgrade-file-format, bookmark-upgrade-file-format-from-0, bookmark-upgrade-version-0-alist --- ** The mantemp.el library is now marked obsolete. This library generates manual C++ template instantiations. It should no longer be useful on modern compilers, which do this automatically. ** Ispell --- *** New hook 'ispell-change-dictionary-hook'. This runs after changing the dictionary and could be used to automatically spellcheck a buffer when changing language without needing to advice 'ispell-change-dictionary'. ** scroll-lock --- *** New command 'scroll-lock-next-line-always-scroll'. This command is bound to 'S-down' and scrolls the buffer up in particular when the end of the buffer is visible in the window. ** mwheel.el --- *** 'mwheel-install' is now obsolete. Use 'mouse-wheel-mode' instead. Note that 'mouse-wheel-mode' is already enabled by default on most graphical displays. ** Gravatar +++ *** 'gravatar-cache-ttl' is now a number of seconds. The previously used timestamp format of a list of integers is still supported, but is deprecated. The default value has not changed. +++ *** 'gravatar-size' can now be nil. This results in the use of Gravatar's default size of 80 pixels. +++ *** The default fallback gravatar is now configurable. This is possible using the new user options 'gravatar-default-image' and 'gravatar-force-default'. ** ada-mode *** The built-in ada-mode is now deleted. The GNU ELPA package is a good replacement, even in very large source files. * New Modes and Packages in Emacs 27.1 ** fileloop.el lets one setup multifile operations like search&replace. +++ ** Emacs can now visit files in archives as if they were directories. This feature uses Tramp and works only on systems which support GVFS, i.e. GNU/Linux, roughly spoken. See the node "(tramp) Archive file names" in the Tramp manual for full documentation of these facilities. +++ ** New library for writing JSONRPC applications (https://jsonrpc.org). 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. +++ ** 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 and ERT. See the node "(elisp) Backtraces" in the Elisp manual for documentation of the new mode and its commands. +++ ** so-long.el helps to mitigate performance problems with long lines. When 'global-so-long-mode' has been enabled, visiting a file with very long lines will (subject to configuration) cause the user's preferred 'so-long-action' to be automatically invoked (by default, the buffer's major mode is replaced by 'so-long-mode'). In extreme cases this can prevent delays of several minutes, and make Emacs responsive almost immediately. Type 'M-x so-long-commentary' for full documentation. * Incompatible Lisp Changes in Emacs 27.1 --- ** The REGEXP in 'magic-mode-alist' is now matched case-sensitively. Likewise for 'magic-fallback-mode-alist'. +++ ** 'add-hook' does not always add to the front or the end any more. The replacement of 'append' with 'depth' implies that the function is not always added to the very front (when append/depth is nil) or the very end (when append/depth is t) any more because other functions on the hook may have specified higher/lower depths. This makes it possible to control the ordering of functions more precisely, as was already possible in 'add-function' and 'advice-add'. ** In 'compilation-error-regexp-alist' the old undocumented feature where 'line' could be a function of 2 arguments has been dropped. ** 'define-fringe-bitmap' is always defined, even when Emacs is built without any GUI support. --- ** 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 did before. However, loading the theme's file with 'M-x load-file', 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. ** The REPETITIONS argument of 'benchmark-run' can now also be a variable. ** 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. ** 'file-name-absolute-p' no longer considers "~foo" to be an absolute file name if there is no user named "foo". ** The FILENAME argument to 'file-name-base' is now mandatory and no longer defaults to 'buffer-file-name'. +++ ** File metadata primitives now signal an error if I/O, access, or other serious errors prevent them from determining the result. Formerly, these functions often (though not always) returned nil. For example, if there is an access error, I/O error or low-level integer overflow when getting the attributes of a file F, (file-attributes F) now signals an error instead of returning nil. These functions still behave as before if the only problem is that the file does not exist. The affected primitives are directory-files-and-attributes, file-acl, file-attributes, file-modes, file-newer-than-file-p, file-selinux-context, file-system-info, and set-visited-file-modtime. --- ** 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. ** 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. ** 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 implementation to format. ** 'logb' now returns infinity when given an infinite or zero argument, and returns a NaN when given a NaN. Formerly, it returned an extreme fixnum for such arguments. --- ** Some functions and variables obsolete since Emacs 22 have been removed: archive-mouse-extract, assoc-ignore-case, assoc-ignore-representation, backward-text-line, blink-cursor, bookmark-exit-hooks, c-opt-op-identitier-prefix, 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, 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, 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, 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, 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, tooltip-gud-toggle-dereference, unfocus-frame, unload-hook-features-list, 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, 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. ** Garbage collection no longer treats miscellaneous objects specially; 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. +++ ** Reversed character ranges are no longer permitted in 'rx'. Previously, ranges where the starting character is greater than the ending character were silently omitted. For example, '(rx (any "@z-a" (?9 . ?0)))' would match '@' only. Now, such 'rx' expressions generate an error. +++ ** 'text-mode' no longer sets the value of 'indent-line-function'. The global value of 'indent-line-function', which defaults to 'indent-relative', will no longer be reset locally when turning on 'text-mode'. To get back the old behavior, add a function to 'text-mode-hook' which performs '(setq-local indent-line-function #'indent-relative)'. ** 'make-process' no longer accepts a non-nil ':stop' key. This has never worked reliably, and now causes an error. +++ ** 'eventp' no longer returns non-nil for lists whose car is nil. This is consistent with the fact that nil, though a symbol, is not a valid event type. --- ** The obsolete package xesam.el (since Emacs 24) has been removed. * Lisp Changes in Emacs 27.1 ** 'reveal-mode' can now also be used for more than to toggle between invisible and visible: It can also toggle 'display' properties in overlays. This is only done on 'display' properties that have the 'reveal-toggle-invisible' property set. +++ ** 'process-contact' now takes an optional NO-BLOCK parameter to allow not waiting for a process to be set up. +++ ** The new 'quit-window-hook' is now run first when executing the 'quit-window' command. ** The variables 'help-enable-completion-auto-load', 'help-enable-auto-load' and 'vhdl-project-auto-load', as well as the 'vhdl-auto-load-project' have been renamed to have "autoload" without the hyphen in their names. Obsolete aliases from the old names have been added. +++ ** Buttons (created with 'make-button' and related functions) can now use the 'button-data' property. If present, the data in this property will be passed on to the 'action' function instead of the button itself in 'button-activate'. ** 'defcustom' now takes a ':local' keyword that can be either t or 'permanent', which mean that the variable should be automatically buffer-local. 'permanent' also sets the variable's 'permanent-local' property. +++ ** The new macro 'with-suppressed-warnings' can be used to suppress specific byte-compile warnings. +++ ** The new macro 'ignore-error' is like 'ignore-errors', but takes a specific error condition, and will only ignore that condition. (This can also be a list of conditions.) --- ** The new function 'byte-compile-info-message' can be used to output informational messages that look pleasing during the Emacs build. --- ** New 'help-fns-describe-variable-functions' hook. Makes it possible to add metadata information to 'describe-variable'. ** i18n (internationalization) *** ngettext can be used now to return the right plural form according to the given numeric value. +++ ** 'inhibit-null-byte-detection' is renamed to 'inhibit-nul-byte-detection'. +++ ** 'self-insert-command' takes the char to insert as (optional) argument. ** 'lookup-key' can take a list of keymaps as argument. +++ ** 'condition-case' now accepts 't' to match any error symbol. +++ ** New function 'proper-list-p'. Given a proper list as argument, this predicate returns its length; otherwise, it returns nil. 'format-proper-list-p' is now an obsolete alias for the new function. +++ ** 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.) 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. 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 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. ** Time values +++ *** New function time 'time-convert' converts Lisp time values to Lisp timestamps of various forms, including a new timestamp form (TICKS . HZ) where TICKS is an integer and HZ a positive integer denoting a clock frequency. +++ *** 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 'format-time-string', 'decode-time', and 'time-convert' rather than probing the innards of a timestamp directly, or creating a timestamp by hand. +++ *** Decoded (calendrical) timestamps now have subsecond resolution. This affects decode-time, which generates these timestamps, as well as functions like encode-time that accept them. The subsecond info is present as a (TICKS . HZ) value in the seconds element of a decoded timestamp, and decode-time has a new optional FORM argument specifying the form of the seconds member. For example, if X is the timestamp (1566009571321878186 . 1000000000), which represents 2019-08-17 02:39:31.321878186 UTC, (decode-time X t t) returns ((31321878186 . 1000000000) 39 2 17 8 2019 6 nil 0) instead of the traditional (31 39 2 17 8 2019 6 nil 0) returned by plain (decode-time X t). Although the default FORM is currently 'integer', which truncates the seconds to an integer and is the traditional behavior, this default may change in future Emacs versions, so callers requiring an integer should specify FORM explicitly. +++ *** 'encode-time' supports a new API '(encode-time TIME)'. The old 'encode-time' API is still supported. +++ *** A new package to parse ISO 8601 time, date, durations and intervals has been added. The main function to use is 'iso8601-parse', but there's also 'iso8601-parse-date', 'iso8601-parse-time', 'iso8601-parse-duration' and 'iso8601-parse-interval'. All these functions return decoded time structures, except the final one, which returns three of them (start, end and duration). +++ *** '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. If both arguments are finite, these functions now return exact results instead of rounding in some cases, and they also avoid excess precision when that is easy. +++ *** New function 'time-equal-p' compares time values for equality. +++ *** 'format-time-string' supports a new conversion specifier flag '+' that acts like the '0' flag but also puts a '+' before nonnegative years containing more than four digits. This is for compatibility with POSIX.1-2017. +++ *** To access (or alter) the elements a decoded time value, the 'decoded-time-second', 'decoded-time-minute', 'decoded-time-hour', 'decoded-time-day', 'decoded-time-month', 'decoded-time-year', 'decoded-time-weekday', 'decoded-time-dst' and 'decoded-time-zone' accessors can be used. *** The new functions 'date-days-in-month' (which will say how many days there are in a month in a specific year), 'date-ordinal-to-time' (that computes the date of an ordinal day), 'decoded-time-add' for doing computations on a decoded time structure), 'make-decoded-time' (for making a decoded time structure with only the given keywords filled out), and 'encoded-time-set-defaults' (which fills in nil elements as if it's midnight January 1st, 1970) have been added. ** 'define-minor-mode' automatically documents the meaning of ARG. +++ ** 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. +++ ** New functions 'major-mode-suspend' and 'major-mode-restore'. Use them when switching temporarily to another major mode, e.g. for 'hexl-mode', or to switch between 'c-mode' and 'image-mode' in XPM. +++ ** New macro 'dolist-with-progress-reporter'. This works like 'dolist', but reports progress similar to 'dotimes-with-progress-reporter'. +++ ** New hook 'after-delete-frame-functions'. This works like 'delete-frame-functions', but runs after the frame to be deleted has been made dead and removed from the frame list. --- ** The function 'provided-mode-derived-p' was extended to support aliases. The function now returns non-nil when the argument MODE is derived from any alias of any of MODES. +++ ** New frame focus state inspection interface. The hooks 'focus-in-hook' and 'focus-out-hook' are now obsolete. Instead, attach to 'after-focus-change-function' using 'add-function' and inspect the focus state of each frame using 'frame-focus-state'. +++ ** Emacs now requests and recognizes focus-change notifications from TTYs. On terminal emulators that support the feature, Emacs can now support 'focus-in-hook' and 'focus-out-hook' for TTY frames. +++ ** Window-specific face remapping. Face specifications (of the kind used in 'face-remapping-alist') now support filters, allowing faces to vary between different windows displaying the same buffer. See the node "(elisp) Face Remapping" of the Emacs Lisp Reference manual for more detail. +++ ** Window change functions have been redesigned. Hooks reacting to window changes run now only when redisplay detects that a change has actually occurred. Six hooks are now provided: 'window-buffer-change-functions' (run after window buffers have changed), 'window-size-change-functions' (run after a window was assigned a new buffer or size), 'window-configuration-change-hook' (like the former but run also when a window was deleted), 'window-selection-change-functions' (run when the selected window changed) and 'window-state-change-functions' and 'window-state-change-hook' (run when any of the preceding ones is run). Applications can enforce running the latter two using the new function 'set-frame-window-state-change'. 'window-scroll-functions' are unaffected by these changes. In addition, a number of functions now allow the caller to detect what has changed since last redisplay: 'window-old-buffer' returns for any window the buffer it showed at that time. ‘old-selected-window’ and 'old-selected-frame' return the window and frame that were selected during last redisplay. 'window-old-pixel-width' (renamed from 'window-pixel-width-before-size-change'), 'window-old-pixel-height' (renamed from 'window-pixel-height-before-size-change'), 'window-old-body-pixel-width' and 'window-old-body-pixel-height' return the total and body sizes of any window during last redisplay. See the section "(elisp) Window Hooks" in the Elisp manual for a detailed explanation of the new behavior. +++ ** Making scroll bar and fringe settings persistent for windows. The functions 'set-window-scroll-bars' and 'set-window-fringes' now have a new optional argument that makes the settings they produce reliably survive subsequent invocations of 'set-window-buffer'. +++ ** New option 'resize-mini-frames'. This option allows to automatically resize minibuffer-only frames similarly to how minibuffer windows are resized on "normal" frames. +++ ** New buffer display action function 'display-buffer-in-direction'. This function allows to specify the location of the window chosen by 'display-buffer' in various ways. +++ ** New buffer display action alist entry 'dedicated'. Such an entry allows to specify the dedicated status of a window created by 'display-buffer'. +++ ** New buffer display action alist entry 'window-min-height'. Such an entry allows to specify a minimum height of the window used for displaying a buffer. 'display-buffer-below-selected' is the only action function to respect it at the moment. +++ ** New buffer display action alist entry 'direction'. This entry is used to specify the location of the window chosen by 'display-buffer-in-direction'. +++ ** Additional meaning of display action alist entry 'window'. A 'window' entry can now also specify a reference window for 'display-buffer-in-direction'. +++ ** The function 'assoc-delete-all' now takes an optional predicate argument. +++ ** New function 'string-distance' to calculate the Levenshtein distance between two strings. ** 'print-quoted' now defaults to t, so if you want to see '(quote x)' instead of 'x you will have to bind it to nil where applicable. +++ ** Numbers formatted via '%o' or '%x' are now formatted as signed integers. This avoids problems in calls like '(read (format "#x%x" -1))', and is more compatible with bignums. To get the traditional machine-dependent behavior, set the experimental variable 'binary-as-unsigned' to t, and if the new behavior breaks your code please email <32252@debbugs.gnu.org>. Because '%o' and '%x' can now format signed integers, they now support the '+' and space flags. ** To avoid confusion caused by "smart quotes", the reader signals an error when reading Lisp symbols which begin with one of the following quotation characters: ‘’‛“”‟〞＂＇. A symbol beginning with such a character can be written by escaping the quotation character with a backslash. For example: (read "‘smart") => (invalid-read-syntax "strange quote" "‘") (read "\\‘smart") == (intern "‘smart") +++ ** Omitting variables after '&optional' and '&rest' is now allowed. For example '(defun foo (&optional))' is no longer an error. This is sometimes convenient when writing macros. See the ChangeLog entry titled "Allow '&rest' or '&optional' without following variable (Bug#29165)" for a full listing of which arglists are accepted across versions. ** Internal parsing commands now use 'syntax-ppss' and disregard 'open-paren-in-column-0-is-defun-start'. This affects mostly things like 'forward-comment', 'scan-sexps', and 'forward-sexp' when parsing backward. The new variable 'comment-use-syntax-ppss' can be set to nil to recover the old behavior if needed. ** The 'server-name' and 'server-socket-dir' variables are set when a socket has been passed to Emacs. --- ** The 'file-system-info' function is now available on all platforms. instead of just Microsoft platforms. This fixes a 'get-free-disk-space' bug on OS X 10.8 and later. --- ** The function 'get-free-disk-space' returns now a non-nil value for remote systems, which support this check. +++ ** 'memory-limit' now returns a better estimate of memory consumption. +++ ** When interpreting 'gc-cons-percentage', Emacs now estimates the heap size more often and (we hope) more accurately. E.g., formerly (progn (let ((gc-cons-percentage 0.8)) BODY1) BODY2) continued to use the 0.8 value during BODY2 until the next garbage collection, but that is no longer true. Applications may need to re-tune their GC tricks. +++ ** New macro 'combine-change-calls' arranges to call the change hooks ('before-change-functions' and 'after-change-functions') just once each around a sequence of lisp forms, given a region. This is useful when a function makes a possibly large number of repetitive changes and the change hooks are time consuming. +++ ** 'eql', 'make-hash-table', etc. now treat NaNs consistently. Formerly, some of these functions ignored signs and significands of NaNs. Now, all these functions treat NaN signs and significands as significant. For example, '(eql 0.0e+NaN -0.0e+NaN)' now returns nil because the two NaNs have different signs; formerly it returned t. Also, Emacs now reads and prints NaN significands; e.g., if X is a NaN, '(format "%s" X)' now returns "0.0e+NaN", "1.0e+NaN", etc., depending on X's significand. +++ ** The function 'make-string' accepts an additional optional argument. If the optional third argument is non-nil, 'make-string' will produce a multibyte string even if its second argument is an ASCII character. ** '(format "%d" X)' no longer mishandles a floating-point number X that does not fit in a machine integer. --- ** New coding-system 'ibm038'. This is the International EBCDIC encoding, also available as aliases 'ebcdic-int' and 'cp038'. +++ ** In the DST slot, 'encode-time' and 'parse-time-string' now return -1 if it is not known whether daylight saving time is in effect. Formerly they were inconsistent: 'encode-time' returned t in this situation, whereas 'parse-time-string' returned nil. Now they consistently use use nil to mean that DST is not in effect, and use -1 to mean that it is not known whether DST is in effect. ** New JSON parsing and serialization functions 'json-serialize', 'json-insert', 'json-parse-string', and 'json-parse-buffer'. These are implemented in C using the Jansson library. +++ ** New function 'ring-resize'. 'ring-resize' can be used to grow or shrink a ring. +++ ** New function 'flatten-tree'. 'flatten-list' is provided as an alias. These functions take a tree and 'flatten' it such that the result is a list of all the terminal nodes. +++ ** 'zlib-decompress-region' can partially decompress corrupted data. If the new optional ALLOW-PARTIAL argument is passed, then the data that was decompressed successfully before failing will be inserted into the buffer. ** Mailcap --- *** The new function 'mailcap-file-name-to-mime-type' has been added. It's a simple convenience function for looking up MIME types based on file name extensions. *** The default way the list of possible external viewers for MIME types is sorted and chosen has changed. Earlier, the most specific viewer was chosen, even if there was a general override in "~/.mailcap". For instance, if "/etc/mailcap" has an entry for "image/gif", that one will be chosen even if you have an entry for "image/*" in your "~/.mailcap" file. But with the new method, entries from "~/.mailcap" overrides all system and Emacs-provided defaults. To get the old method back, set 'mailcap-prefer-mailcap-viewers' to nil. ** URL *** The 'file:' handler no longer looks for "index.html" in directories if you ask it for a "file:///dir" URL. Since this is a low-level library, such decisions (if they are to be made at all) are left to higher-level functions. ** Image mode *** New library Exif. An Exif library has been added that can parse JPEG files and output data about creation times and orientation and the like. 'exif-parse-file' and 'exif-parse-buffer' are the main interface functions. *** 'image-mode' now uses this library to automatically rotate images according to the orientation in the Exif data, if any. *** 'imagemagick-types-inhibit' disables using ImageMagick by default. 'image-mode' started using ImageMagick by default for all images some years back. It now respects 'imagemagick-types-inhibit' as a way to disable that. --- *** Some 'image-mode' variables are now buffer-local. The image parameters 'image-transform-rotation', 'image-transform-scale' and 'image-transform-resize' are now declared buffer-local, so each buffer could have its own values for these parameters. +++ *** The command 'image-rotate' now accepts a prefix argument. With a prefix argument, 'image-rotate' now rotates the image at point 90 degrees counter-clockwise, instead of the default clockwise. ** Modules *** The function 'load' now behaves correctly when loading modules. Specifically, it puts the module name into 'load-history', prints loading messages if requested, and protects against recursive loads. *** New module environment function 'process_input' to process user input while module code is running. *** New module environment functions 'make_time' and 'extract_time' to convert between timespec structures and Emacs Lisp time values. *** New module environment functions 'make_big_integer' and 'extract_big_integer' to create and extract arbitrary-size integer values. *** emacs-module.h now defines a macro 'EMACS_MAJOR_VERSION' that expands to the major version of the latest Emacs supported by the header. +++ ** The function 'read-variable' now uses its own history list. The history of variable names read by 'read-variable' is recorded in the new variable 'custom-variable-history'. --- ** The functions 'string-to-unibyte' and 'string-to-multibyte' are no longer declared obsolete. We have found that there are legitimate use cases for these functions, where there's no better alternative. We believe that the incorrect uses of these functions all but disappeared by now, so we are un-obsoleting them. +++ ** New function 'group-name' returns a group name corresponding to GID. +++ ** 'make-process' now takes a keyword argument ':file-handler'; if that is non-nil, it will look for a file name handler for the current buffer's 'default-directory' and invoke that file name handler to make the process. That way 'make-process' can start remote processes. +++ ** Emacs now supports resizing and rotating images without ImageMagick. All modern systems support this feature. (On GNU and Unix systems, Cairo drawing or the XRender extension to X11 is required for this to be available; the configure script will test for it and, if found, enable scaling.) The new function 'image-transforms-p' can be used to test whether any given frame supports these capabilities. +++ ** '(locale-info 'paper)' now returns the paper size on systems that support it. This is currently supported on GNUish hosts and on modern versions of MS-Windows. +++ ** The function 'regexp-opt' accepts an additional optional argument. By default, the regexp returned by 'regexp-opt' may match the strings in any order. If the new third argument is non-nil, the match is guaranteed to be performed in the order given, as if the strings were made into a regexp by joining them with '\|'. +++ ** The function 'regexp-opt', when given an empty list of strings, now returns a regexp that never matches anything, which is an identity for this operation. Previously, the empty string was returned in this case. ** New constant 'regexp-unmatchable' contains a never-matching regexp. It is a convenient and readable way to specify a regexp that should not match anything, and is as fast as any such regexp can be. ++++ ** New functions to handle the URL variant of base-64 encoding. New functions 'base64url-encode-string' and 'base64url-encode-region' implement the url-variant of base-64 encoding as defined in RFC4648. The functions 'base64-decode-string' and 'base64-decode-region' now accept an optional argument to decode the URL variant of base-64 encoding. +++ ** The function 'file-size-human-readable' accepts more optional arguments. The new third argument is a string put between the number and unit; it defaults to the empty string. The new fourth argument is a string representing the unit to use; it defaults to "B" when the second argument is 'iec' and the empty string otherwise. We recomment a space or non-breaking space as third argument, and "B" as fourth argument, circumstances allowing. +++ ** 'format-spec' has been expanded with several modifiers to allow greater flexibility when customizing variables. The modifiers include zero-padding, upper- and lower-casing, and limiting the length of the interpolated strings. The function has now also been documented in the Emacs Lisp manual. +++ ** 'directory-files-recursively' can now take an optional PREDICATE parameter to control descending into subdirectories, and a FOLLOW-SYMLINK parameter to say that symbolic links that point to other directories should be followed. +++ ** New function 'xor' returns the boolean exclusive-or of its args. The function was previously defined in array.el, but has been moved to subr.el so that it is available by default. It now always returns the non-nil argument when the other is nil. Several duplicates of 'xor' in other packages are now obsolete aliases of 'xor'. +++ ** 'define-globalized-minor-mode' now takes BODY forms. * Changes in Emacs 27.1 on Non-Free Operating Systems --- ** Battery status is now supported in all Cygwin builds. Previously it was supported only in the Cygwin-w32 build. ** Emacs now handles key combinations involving the macOS "command" and "option" modifier keys more correctly. ** The special handling of 'frame-title-format' on NS where setting it to 't' would enable the macOS proxy icon has been replaced with a separate variable, 'ns-use-proxy-icon'. 'frame-title-format' will now work as on other platforms. --- ** New primitive 'w32-read-registry'. This primitive lets Lisp programs access the MS-Windows Registry by retrieving values stored under a given key. It is intended to be used for supporting features such as XDG-like location of important files and directories. +++ ** The default value of 'w32-pipe-read-delay' is now zero. This speeds up reading output from sub-processes that produce a lot of data. This variable may need to be non-zero only when running DOS programs as Emacs subprocesses, which by now is not supported on modern versions of MS-Windows. Set this variable to 50 if for some reason you need the old behavior (and please report such situations to Emacs developers). --- ** New variable 'w32-multibyte-code-page'. This variable holds the value of the multibyte code page used by the system. It is usually zero, which indicates that 'w32-ansi-code-page' is being used, except in Far Eastern locales. When this variable is non-zero, Emacs at startup sets 'locale-coding-system' to the corresponding encoding, instead of using 'w32-ansi-code-page'. --- ** The default value of 'inhibit-compacting-font-caches' is t on MS-Windows. Experience shows that compacting font caches causes more trouble on MS-Windows than it helps. +++ ** Font lookup on MS-Windows was improved to support rare scripts. To activate the improvement, run the new function 'w32-find-non-USB-fonts' once per Emacs session, or assign to the new variable 'w32-non-USB-fonts' the list of scripts and the corresponding fonts. See the documentation of this function and variable in the Emacs manual for more details. +++ ** On NS the behaviour of drag and drop can now be modified by use of modifier keys in line with Apples guidelines. This makes the drag and drop behaviour more consistent, as previously the sending application was able to 'set' modifiers without the knowledge of the user. ** On NS multicolor font display is enabled again since it is also implemented in Emacs on free operating systems via Cairo drawing. ---------------------------------------------------------------------- This file is part of GNU Emacs. GNU Emacs is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. GNU Emacs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Emacs. If not, see . Local variables: coding: utf-8 mode: outline paragraph-separate: "[ ]*$" end: