Changes and New Features in 24.01.1:

   • Revert a bug introduced with the ‘ess-request-a-process’ change

   Changes and New Features in 24.01.0:

   • fix docstring warnings in ess-custom

   • :package-version is now set to "VERSION" in ess-custom.  By make
     this is replaced with "24.01.0" (or similar).

   • Better “collaboration” with org-mode Now ‘ess-request-a-process’
     obeys ‘ess-gen-proc-buffer-name-function’, thanks to Ihor
     Radchenko.

   Changes and New Features in 19.04 (unreleased):

   • ESS[R]: When a background command is interrupted with C-g, ESS now
     asks the user if they want to disable background evaluations
     altogether.  This is a resiliency measure against cases where
     background evals cause cascading errors or hangs.

   • ESS[R]: Background commands now propagate errors to Emacs.

   • ESS[R]: Background commands can now be disabled by process instad
     of globally.  For instance when a process has failed to initialize
     properly, background evals are disabled for that particular process
     to avoid cascading errors.  Other processes may still use
     background commands.

   • ESS[R]: ESSR commands are now more robust when ESSR is not in
     scope.  This can happen when using ‘browser()’ in an environment
     that doesn’t inherit from the search path.

   • ESS[R]: Unexpected exits are now detected during startup.  In that
     case an error is thrown with advice about how to recover.

   • ESS[R]: ‘options(width = )’ is now set on startup based on the
     width of the inferior window.

   • ESS[R]: Add support for R projects and start R by default in the
     project folder.

   • ESS[R]: Backticked symbols in the process buffer are no longer
     fontified as strings.

   • ESS[R]: ‘ess-command’ now runs R code in a sandboxed environment.
     Use ‘.ess.environment()’ to inspect the current environment.

   • ESS[R]: Added support for new syntax in R 4.0 and R 4.1.  This
     concerns raw strings, lambda functions, and the pipe operator.

   • ESS[R]: Highlight error locations in rlang style backtraces

   • ESS[R]: Fixed issue that caused ESS-help to hang when usage blocks
     include R comments (#1025).  Fix contributed by Bill Evans.

   • ESS: New ‘ess-elisp-trace-mode’ minor mode.  Toggle it to start or
     stop tracing all ‘ess’-prefixed functions with ‘trace-function’.
     Tracing is useful for debugging background ESS behaviour.

   • ESS[R]: ‘ess-get-help-aliases-list’ now caches the aliases on the R
     side.  This should speed up help lookup when the search path has
     changed and the aliases are read again.

   • ESS: ‘ess-command’ now uses a default timeout of 30 seconds.  It
     should normally be avoided with long-running tasks because it
     causes Emacs to block while the command is running.  If the timeout
     is reached, an error is thrown.  An interrupt is also sent to the
     process in case of early exit.

     This is a behaviour change: you will now have to explicitly opt in
     blocking the whole Emacs UI for more than 30 seconds by supplying a
     larger timeout (use ‘most-positive-fixnum’ for infinity).

   • ESS: ‘ess-wait-for-process’ now returns nil if a timeout is
     reached.

   • ESS: ‘ess-get-words-from-vector’ gains a ‘timeout’ argument.

   • ESS[R]: Fixed performance issue with argument completions.  The
     help summary for the argument is no longer displayed in the echo
     area.  This fixes delays and hangs (#1062).

   • ESS[R]: ‘ess-command’ is now more robust and resilient to hangs and
     custom prompts (#1043).  It also strips continuation prompts (‘+’
     prompts) automatically and reliably (#1116).

   • ESS[R]: ‘ess-command’ now handles sinked consoles correctly.

   • ESS[R]: ‘ess-command’ no longer changes ‘.Last.value’.  As a
     result, background tasks like completions no longer affect the last
     value binding (#1058).

   • ESS[R]: Namespaced evaluation is disable in roxygen examples
     (#1026).  Part of this change is that namespaced evaluation has
     become a buffer-local rather than process-local setting (#1046).
     This makes it possible to disable namespaced evaluation in specific
     buffers or contexts.

   • iESS: Inferior processes can now properly reuse frames (#987).
     Fixed issue that caused the current buffer to be incorrectly
     displayed in the new frame when ‘display-buffer’ is set to pop up
     frames.

   • ESS[R]: Better support for tramp.  Fixed package evaluation on
     remote servers with Tramp (#950); process reloading (#1001); and an
     evaluation issue (#1024).  These fixes were contributed by David
     Pritchard.

   • ESS[R]: Automatic offsetting of R process output is now disabled by
     default because it produces undesirable output in some situations.
     To re-enable, set ‘inferior-ess-fix-misaligned-output’ to t.

   • ESS[R]: Improved ‘xref’ lookup (‘M-.’).  Function locations are now
     always detected for package libraries listed in
     ‘ess-r-package-library-paths’.

   • ESS[R]: Evaluated lines starting with the Roxygen prefix are now
     always stripped from the prefix, so they can be sent to the process
     easily.  Previously, this was only the case inside the ‘examples’
     field.  Since roxygen is switching to R markdown, it becomes useful
     to evaluate chunks of R outside examples.

   • stata support is now obsolete since we were unable to elicit FSF
     paperwork from some of the original authors: see the lisp/obsolete
     sub-directory on the ESS github repo

   • ‘ess-set-working-directory’ no longer changes the active directory
     (as defined by the buffer-local variable ‘default-directory’) of
     the buffer where the command is called.  Instead, the active
     directory of the inferior buffer is updated to the new working
     directory.

   • The default of ess-eval-visibly is now ‘'nowait’.  With this change
     you should no longer experience freezes while evaluating code.

   • ESS[R]: There is a new menu entry for reloading the R process.  It
     is otherwise bound to ‘C-c C-e C-r’.  Reloading now reuses the same
     process name and start arguments that were used to start the
     process.

   • iESS: Process runners now return the inferior buffer.  Note that
     callers of inferior runners should not assume that the current
     buffer has been set to the inferior buffer.  Instead, use
     ‘with-current-buffer’ with the return value of the inferior.

   • iESS[SAS]: The SAS keymap was only set in iESS buffers called
     ‘*SAS*‘.  This is now fixed.

   • ESS[R]: Fixed longstanding indentation issues involving ‘::’ and
     ‘:::’ operators.

   • Implement a more reliable check for the process busy state.
     Background actions such as completion and directory synchronization
     should not block the process and should not cause printing of the
     extraneous output to the interpreter.

   • Activate ‘goto-address-mode’ for url and email highlighting in
     inferior buffers.

   • ‘smart-underscore’ and ‘ess-smart-S-assign-key’ have been removed.
     Users who liked the previous behavior (i.e.  underscore inserting
     “<-”) should bind ‘ess-insert-assign’ to the underscore in their
     Emacs initialization file.  For example, ‘(define-key
     ess-r-mode-map "_" #'ess-insert-assign)’ and ‘(define-key
     inferior-ess-r-mode-map "_" #'ess-insert-assign)’ will activate it
     in all ESS R buffers.

   • ESS major modes are now defined using ’define-derived-mode’.  This
     makes ESS major modes respect modern conventions such as having
     <language>-mode-hook and <language>-mode-map.  Users are encouraged
     to place customizations under the appropriate mode.

   • New option ess-auto-width controls setting the width option on
     window changes.  Users can change it to ’frame, ’window, or an
     integer.  See the documentation for details.
     ‘ess-auto-width-visible’ controls visibility.

   • ESS now respects ‘display-buffer-alist’.  Users can now use
     ‘display-buffer-alist’ to manage how and where windows appear.  For
     more information and examples, see *Note (ess)Controlling buffer
     display::.

   • ‘ess-roxy-mode’ can now be enabled in non-R buffers.  This is
     primarily intended to support roxygen documentation for cpp
     buffers.  Preview functionality is not supported outside R buffers.

   • ESS[R]: DESCRIPTION files now open in ‘conf-colon-mode’.

   • ‘ess-style’ now has effects when set as a file or directory local
     variable.

   • ‘ess-default-style’ is now obsolete, use ‘ess-style’ instead.

   • Options for ’ess-gen-proc-buffer-name-function’ have been renamed.
     ess-gen-proc-buffer-name:projectile-or-simple was renamed to
     ess-gen-proc-buffer-name:project-or-simple and
     ess-gen-proc-buffer-name:projectile-or-directory was renamed to
     ess-gen-proc-buffer-name:project-or-directory.  As the name
     suggests, these now rely on project.el (included with Emacs) rather
     than projectile.el, which is a third-party package.

   • Eldoc fully honors ‘eldoc-echo-area-use-multiline-p’

   • ESS[R]: ‘ess-r-rhub-check-package’ gained new ‘RECOMMENDED’.

   • ESS[R]: devtools commands ask about saving modified buffers before
     running.  Users can disable the questioning with
     ‘ess-save-silently’.

   • ESS[R] help pages now provide links to other help topics.  This is
     similar with what you would see with, for example
     ‘options(help_type = ``html'')’ but works with the plain-text
     version as well.  This only works with ‘options(useFancyQuotes =
     TRUE)’ (the default).

   • ‘ess-rdired’ buffers now derive from tabulated-list-mode.  They
     should look better and be a bit faster overall.  The size column
     now displays object sizes in bytes.

   • ‘ess-rdired’ buffers now auto-update.  The frequency is governed by
     the new option ‘ess-rdired-auto-update-interval’.

   • ESS[R]: ‘electric-layout-mode’ is now supported.  This
     automatically inserts a newline after an opening curly brace in R
     buffers.  To enable it, customize ‘ess-r-mode-hook’.

   • ESS[R]: imenu now supports assignment with the equals sign.

   • ESS[Rd]: Rd no longer writes abbrevs to user’s abbrev file.

   • ESS removed support for many unused languages.  This includes old
     versions of S+, ARC, OMG, VST, and XLS.

   • ess-r-runner-prefixes was modified to find R-4 and later.

   • ESS no longer activates eldoc if the user has disabled
     global-eldoc-mode.

   The following have been made obsolete or removed, see their
documentation for more detail:

   • Libraries for literate data analysis are obsolete and not loaded by
     default.  This includes ‘ess-noweb’, ‘ess-swv’, and related
     functionality like ‘Rnw-mode’.  Users are encouraged to switch to
     one of several other packages that deal with these modes.  For
     example, polymode <https://github.com/polymode/poly-R/>,
     <https://polymode.github.io/>, or markdown-mode with edit-indirect
     <https://jblevins.org/projects/markdown-mode>.

   • Support for ‘auto-complete’ is obsolete.  The ‘auto-complete’
     package is unmaintained and so ESS support is now obsolete.  Users
     are encouraged to switch to ‘company-mode’ instead.

   • User options for controlling display of buffers.  This includes
     ‘ess-show-buffer-action’, ‘inferior-ess-same-window’,
     ‘inferior-ess-own-frame’, and ‘inferior-ess-frame-alist’.  See
     above about ESS respecting ‘display-buffer-alist’.

   • Variables ‘ess-tab-always-indent’ and ‘ess-tab-complete-in-script’.
     Use the Emacs-wide setting of ‘tab-always-indent’ instead.

   • ‘inferior-ess-*-start-file’ variables.  All modes except Stata did
     not respect customization of this variable.  In order to load a
     file on startup, you should put a function on
     ‘ess-*-post-run-hook’.

   Bug Fixes in 18.10.3:
   • More ‘Makefile’ fixes, notably installing ‘*.el’s.

   Bug Fixes in 18.10.2:
   • ESS[R] Fix namespace evaluation in non-installed packages.
     Evaluation is directed into GlobalEnv as originally intended.
   • ‘Makefile’ fixes, notably for ‘make install’ and including full
     docs in the tarballs.

   Bug Fixes in 18.10.1:
   • New functions ‘ess-eval-line-visibly-and-step’ (‘C-c C-n’ and
     ‘ess-eval-region-or-line-visibly-and-step’ (‘C-RET’) which behave
     as the old versions of ‘ess-eval-line-and-step’ and
     ‘ess-eval-region-or-line-and-step’.

   Changes and New Features in 18.10:

   • This is the last release to support Emacs older than 25.1.  Going
     forward, only GNU Emacs 25.1 and newer will be supported.  Soon
     after this release, support for older Emacs versions will be
     dropped from the git master branch.  Note that MELPA uses the git
     master branch to produce ESS snapshots, so if you are using Emacs <
     25.1 from MELPA and are unable to upgrade, you should switch to
     MELPA-stable.

   • ESS now displays the language dialect in the mode-line.  So, for
     example, R buffers will now show ESS[R] rather than ESS[S].

   • The ESS manual has been updated and revised.

   • The ESS initialization process has been further streamlined.  If
     you update the autoloads (which installation from ‘package-install’
     does), you should not need to ‘(require 'ess-site)’ at all, as
     autoloads should automatically load ESS when it is needed (e.g.
     the first time an R buffer is opened).  In order to defer loading
     your ESS config, you may want to do something like
     ‘(with-require-after-load "ess" <ess-config-here>)’ in your Emacs
     init file.  Users of the popular ‘use-package’ Emacs package can
     now do ‘(use-package ess :defer t)’ to take advantage of this
     behavior.  For more information on this feature, see *Note
     (ess)Activating and Loading ESS::.

   • ESS now respects Emacs conventions for keybindings.  This means
     that The ‘C-c [letter]’ bindings have been removed.  This affects
     ‘C-c h’, which was bound to ‘ess-eval-line-and-step-invisibly’ in
     ‘sas-mode-local-map’; ‘C-c f’, which was bound to
     ‘ess-insert-function-outline’ in ‘ess-add-MM-keys’; and ‘C-c h’,
     which was bound to ‘ess-handy-commands’ in ‘Rd-mode-map’,
     ‘ess-noweb-minor-mode-map’, and ‘ess-help-mode-map’

   • Functions ‘ess-eval-line-and-step’ and
     ‘ess-eval-region-or-line-and-step’ now behave consistently with
     other evaluation function inside a package.

   • ESS[R]: ‘ess-r-package-use-dir’ now works with any mode.  This sets
     the working directory to the root of the current package including
     for example C or C++ files within ‘/src’).

   • ESS[R]: Long + + prompts in the inferior no longer offset output.

   • ESS[R]: New option ‘strip’ for ‘inferior-ess-replace-long+’.  This
     strips the entire + + sequence.

   • ESS modes now inherit from ‘prog-mode’.  In the next release, ESS
     modes will use ‘define-derived-mode’ so that each mode will have
     (for example) its own hooks and keymaps.

   • ESS[R]: Supports flymake in R buffers for Emacs 26 and newer.
     Users need to install the ‘lintr’ package to use it.  Customizable
     options include ‘ess-use-flymake’, ‘ess-r-flymake-linters’, and
     ‘ess-r-flymake-lintr-cache’.

   • ESS[R]: Gained support for xref in Emacs 25+ *Note (emacs)Xref::.

   • ESS[R]: The startup screen is cleaner.  It also displays the
     startup directory with an explicit ‘setwd()’.

   • ESS[R]: Changing the working directory is now always reflected in
     the process buffer.

   • ESS[R]: ‘Makevars’ files open with ‘makefile-mode’.

   • New variable ‘ess-write-to-dribble’.  This allows users to disable
     the dribble (‘*ESS*’) buffer if they wish.

   • All of the ‘*-program-name’ variables have been renamed to
     ‘*-program’.  Users who previously customized e.g.
     ‘inferior-ess-R-program-name’ will need to update their
     customization to ‘inferior-ess-R-program’.  These variables are
     treated as risky variables.

   • ‘ess-smart-S-assign’ was renamed to ‘ess-insert-assign’.  It
     provides similar functionality but for any keybinding, not just
     ‘_‘.  For instance if you bind it to ‘;‘, repeated invocations
     cycle through between assignment and inserting ‘;‘.

   • ‘C-c C-=’ is now bound to ‘ess-cycle-assign’ by default.  See the
     documentation for details.  New user customization option
     ‘ess-assign-list’ controls which assignment operators are cycled.

   • ESS[R] In remote sessions, the ESSR package is now fetched from
     GitHub.

   • Commands that send the region to the inferior process now deal with
     rectangular regions.  See the documentation of ‘ess-eval-region’
     for details.  This only works on Emacs 25.1 and newer.

   • ESS[R]: Improvements to interacting with iESS in non-R files.
     Interaction with inferior process in non-R files within packages
     (for instance C or C++ files) has been improved.  This is a work in
     progress.

   • ESS[R]: Changing the working directory is now always reflected in
     the process buffer.

   • ESS[JAGS]: *.jog and *.jmd files no longer automatically open in
     JAGS mode.

   Many improvements to fontification:

   • Improved customization for faces.  ESS now provides custom faces
     for (nearly) all faces used and places face customization options
     into their own group.  Users can customize these options using ‘M-x
     customize-group RET ess-faces’.

   • Many new keywords were added to ‘ess-R-keywords’ and
     ‘ess-R-modifiers’.  See the documentation for details.

   • ESS[R]: ‘in’ is now only fontified when inside a ‘for’ construct.
     This avoids spurious fontification, especially in the output buffer
     where ‘in‘ is a common English word.

   • ESS: Font-lock keywords are now generated lazily.  That means you
     can now add or remove keywords from variables like ‘ess-R-keywords’
     in your Emacs configuration file after loading ESS (i.e.  in the
     ‘:config’ section for ‘use-package’ users).

   • ESS[R]: Fontification of roxygen ‘@param’ keywords now supports
     comma-separated parameters.

   • ESS[R]: Certain keywords are only fontified if followed by a
     parenthesis.  Function-like keywords such as ‘if ()’ or ‘stop()’
     are no longer fontified as keyword if not followed by an opening
     parenthesis.  The same holds for search path modifiers like
     ‘library()’ or ‘require()’.

   • ESS[R]: Fixed fontification toggling.  Especially certain syntactic
     elements such as ‘%op%’ operators and backquoted function
     definitions.

   • ESS[R]: ‘ess-font-lock-toggle-keyword’ can be called interactively.
     This command asks with completion for a font-lock group to toggle.
     This functionality is equivalent to the font-lock menu.

   Notable bug fixes:

   • ‘prettify-symbols-mode’ no longer breaks indentation.  This is
     accomplished by having the pretty symbols occupy the same number of
     characters as their non-pretty cousins.  You may customize the new
     variable ‘ess-r-prettify-symbols’ to control this behavior.

   • ESS: Inferior process buffers are now always displayed on startup.
     Additionally, they don’t hang Emacs on failures.

   Obsolete libraries, functions, and variables:

   • The ‘ess-r-args.el’ library has been obsoleted and will be removed
     in the next release.  Use ‘eldoc-mode’ instead, which is on by
     default.

   • Functions and options dealing with the smart assign key are
     obsolete.  The following functions have been made obsolete and will
     be removed in the next release of ESS: ‘ess-smart-S-assign’,
     ‘ess-toggle-S-assign’, ‘ess-toggle-S-assign-key’,
     ‘ess-disable-smart-S-assign’.

     The variable ‘ess-smart-S-assign-key’ is now deprecated and will be
     removed in the next release.  If you would like to continue using
     ‘_‘ for inserting assign in future releases, please bind
     ‘ess-insert-assign’ in ‘ess-mode-map’ the normal way.

   • ESS[S]: Variable ‘ess-s-versions-list’ is obsolete and ignored.
     Use ‘ess-s-versions’ instead.  You may pass arguments by starting
     the inferior process with the universal argument.

   Changes and New Features in 17.11:

   • The ESS initialization process has been streamlined.  You can now
     load the R and Stata modes independently from the rest of ESS. Just
     put ‘(require 'ess-r-mode)’ or ‘(require 'ess-stata-mode)’ in your
     init file.  This is for experienced Emacs users as this requires
     setting up autoloads for ‘.R’ files manually.  We will keep
     maintaining ‘ess-site’ for easy loading of all ESS features.

   • Reloading and quitting the process is now more robust.  If no
     process is attached, ESS now switches automatically to one
     (prompting you for selection if there are several running).
     Reloading and quitting will now work during a debug session or when
     R is prompting for input (for instance after a crash).  Finally,
     the window configuration is saved and restored after reloading to
     prevent the buffer of the new process from capturing the cursor.

   • ESS[R]: New command ‘ess-r-package-use-dir’.  It sets the working
     directory of the current process to the current package directory.

   • ESS[R] Lookup for references in inferior buffers has been improved.
     New variable ‘ess-r-package-source-roots’ contains package
     sub-directories which are searched recursively during the file
     lookup point.  Directories in ‘ess-tracebug-search-path’ are now
     also searched recursively.

   • ESS[R] Namespaced evaluation is now automatically enabled only in
     the ‘R/’ directory.  This way ESS will not attempt to update
     function definitions from a package if you are working from e.g.  a
     test file.

   Changes and New Features in 16.10:

   • ESS[R]: Syntax highlighting is now more consistent.  Backquoted
     names are not fontified as strings (since they really are
     identifiers).  Furthermore they are now correctly recognized when
     they are function definitions or function calls.
   • ESS[R]: Backquoted names and ‘%op%’ operators are recognized as
     sexp.  This is useful for code navigation, e.g.  with ‘C-M-f’ and
     ‘C-M-b’.
   • ESS[R]: Integration of outline mode with roxygen examples fields.
     You can use outline mode’s code folding commands to fold the
     examples field.  This is especially nice to use with well
     documented packages with long examples set.  Set
     ‘ess-roxy-fold-examples’ to non-nil to automatically fold the
     examples field when you open a buffer.
   • ESS[R]: New experimental feature: syntax highlighting in roxygen
     examples fields.  This is turned off by default.  Set
     ‘ess-roxy-fontify-examples’ to non-nil to try it out.
   • ESS[R]: New package development command ‘ess-r-devtools-ask’ bound
     to ‘C-c C-w C-a’.  It asks with completion for any devtools command
     that takes ‘pkg’ as argument.
   • ESS[R]: New command ‘C-c C-e C-r’ to reload the inferior process.
     Currently only implemented for R. The R method runs
     ‘inferior-ess-r-reload-hook’ on reloading.
   • ESS[R]: ‘ess-r-package-mode’ is now activated in non-file buffers
     as well.

   Bug fixes in 16.10:
   • ESS[R]: Fix broken (un)flagging for debugging inside packages
   • ESS[R]: Fixes (and improvements) in Package development
   • ESS[R]: Completion no longer produces ‘...=’ inside ‘list( )’.
   • ESS[R]: Better debugging and tracing in packages.
   • ESS[R]: Better detection of symbols at point.
   • ESS[R]: No more spurious warnings on deletion of temporary files.
   • ESS[julia]: help and completion work (better)
   • ESS[julia]: available via ‘ess-remote’

   Changes and New Features in 16.04:

   • ESS[R]: ‘developer’ functionality has been refactored.  The new
     user interface consists of a single command
     ‘ess-r-set-evaluation-env’ bound by default to ‘C-c C-t C-s’.  Once
     an evaluation environment has been set with, all subsequent ESS
     evaluation will source the code into that environment.  By default,
     for file within R packages the evaluation environment is set to the
     package environment.  Set ‘ess-r-package-auto-set-evaluation-env’
     to ‘nil’ to disable this.
   • ESS[R]: New ‘ess-r-package-mode’ This development mode provides
     features to make package development easier.  Currently, most of
     the commands are based on the ‘devtools’ packages and are
     accessible with ‘C-c C-w’ prefix.  See the documentation of
     ‘ess-r-package-mode’ function for all available commands.  With
     ‘C-u’ prefix each command asks for extra arguments to the
     underlying devtools function.  This mode is automatically enabled
     in all files within R packages and is indicated with ‘[pkg:NAME]’
     in the mode-line.
   • ESS[R]: Help lookup has been improved.  It is now possible to get
     help for namespaced objects such as pkg::foobar.  Furthermore, ESS
     recognizes more reliably when you change ‘options('html_type')’.
   • ESS[R]: New specialized breakpoints for debugging magrittr pipes
   • ESS: ESS now implements a simple message passing interface to
     communicate between ESS and inferior process.

   Bug fixes in 16.04:
   • ESS[R]: Roxygen blocks with backtics are now correctly filled
   • ESS[R]: Don’t skip breakpoints in magrittr’s ‘debug_pipe’
   • ESS[R]: Error highlighting now understands ‘testthat‘ type errors
   • ESS[Julia]: Added getwd and setwd generic commands