MisTTY is a major mode for Emacs 29.1 and up that runs
a shell inside of a buffer, similarly to comint mode. It is built on
top of term.el.
M-x mistty creates a buffer with an interactive shell. See
launching
for details.
MisTTY feels very much like comint mode: you can move around freely
and run any Emacs command you want - until you press TAB and end up
with the native completion or notice the shell autosuggestions. With
MisTTY you have access to both Emacs and the shell commands and
editing tools. Like comint, MisTTY supports remote shells with
TRAMP.
Additionally, commands that take over the entire screen, such as
less or vi also work, temporarily taking over the window, while
scrollback remains available in another buffer.
MisTTY works well with Bash and ZSH, but it is especially well suited to running Fish: you get autosuggestions, completion in full colors. Here's what the end result might look like:
MisTTY is known to work on Linux and MacOS. It also supports non-shell command-line programs, such as python or ipython. MisTTY should work with most shells, but it is possible that a shell confuses it, especially advanced ones. In such a case, please file a bug report.
MisTTY isn't a terminal emulator, but rather a frontend to an existing
terminal emulator, the built-in term.el. Its goal is to make it more
convenient to use while inside of Emacs and better integrate with
Emacs itself. In theory, other terminal emulators than term.el might
be used as engine for MisTTY, such as vterm and eat.
MisTTY has some similarities with coterm; it offers the same switch
between full-screen and line mode.
Coterm, ansi-term and eat all have a line mode, just like
comint. While in line mode, rendering is done by Emacs and editing
commands are Emacs commands. In constrast, with MisTTY, all rendering
is done by the shell through the terminal. This is why native shell
completion and autosuggestion is available with MisTTY and not with
these other line modes and why you can freely mix shell commands with
Emacs commands while editing the command line.
ansi-term and eat also have a char mode, where rendering and
command execution is handled by the shell, and editing with Emacs
isn't available. The difference with MisTTY is then that MisTTY makes
Emacs editing commands available when possible.
eat also has a semi-char mode, which is the closest there is to
MisTTY. In that mode, Emacs movements commands are available. However,
Emacs commands that modify the buffer, aren't available to edit the
command line. In contrast, MisTTY allows Emacs to navigate to and edit
the whole buffer, then replays changes made to the command-line.
The following is just a quick introduction. Read the full documentation at https://mistty.readthedocs.io/en/latest/
You can install MisTTY:
- from MELPA, by typing
M-x package-install mistty - from source, by executing
(package-vc-install "https://github.com/szermatt/mistty")
Type M-x mistty to launch a new shell buffer in MisTTY mode, then
use it as you would comint.
You'll quickly notice some differences. For example TAB completion working just like in a terminal instead of relying of Emacs completion.
The purple line on the left indicates the portion of the buffer that's a terminal. What you type in there gets sent to the program, usually a shell, and translated by that program. The rest of the buffer is normal, editable, text.
Commands that takes the whole screen such as less or vi take you
into terminal mode for the duration of that command. You can still
access previous commands in the "scrollback" MisTTY buffer by typing
C-c C-j.
If you ever get into a situation where a command needs you to press
keys normally sent to Emacs, such as the arrow keys, press C-c C-q.
It'll send all key strokes directly to the terminal until you exit
the mode by pressing C-g. To send a single key to the terminal
you can also press C-q <key> instead.
You will very likely want to send some keys you use often directly
to the terminal. This is done by binding keys to mistty-send-key
in mistty-prompt-map. For example:
(use-package mistty
:bind (("C-c s" . mistty)
;; bind here the shortcuts you'd like the
;; shell to handle instead of Emacs.
:map mistty-prompt-map
;; fish: directory history
("M-<up>" . mistty-send-key)
("M-<down>" . mistty-send-key)
("M-<left>" . mistty-send-key)
("M-<right>" . mistty-send-key)))In addition to that, unless you're using Bash, which supports it out of the box, you'll also likely want to enable directory tracking in your shell.
See also the documentation for more details on configuring MisTTY .
Please check the FAQ and, if that doesn't help, take the time to file a bug report.
See the Contributing section of the documentation.
MisTTY requires Emacs 29.1 or later.
