(Better) Vim Tmux Resizer

Resize tmux panes and Vim windows with ease.

This is a fork of vim-tmux-navigator which allows resizing panes and windows instead of navigating between them. It is 100% compatible with vim-tmux-navigator so you can have both installed and navigate/resize with similar hotkeys.

NOTE: This requires tmux v1.8 or higher.

Why not use vim-tmux-resizer?

Because this plugin allows for a seamless experience between tmux panes and Vim windows. Vim-tmux-resizer doesn't pass resize bindings to tmux when inside a pane running Vim. Better-vim-tmux-resizer gives more seamless control by enabling resizing tmux within a pane running Vim.

Usage

This plugin provides the following mappings which allow you to resize Vim panes and tmux splits seamlessly.

• <meta-h> => Left
• <meta-j> => Down
• <meta-k> => Up
• <meta-l> => Right

NOTE: You don't need to use your tmux prefix key sequence before using the mappings.

If you want to use alternate key mappings, see the configuration section below.

Installation

Vim

If you don't have a preferred installation method, I recommend using Plug. Assuming you have Plug installed and configured, the following steps will install the plugin:

Add the following line to your ~/.vimrc file:

Plug 'RyanMillerC/better-vim-tmux-resizer'

Then run:

:PlugInstall

tmux

To configure the tmux side of this customization there are two options:

Add a snippet

Add the following to your ~/.tmux.conf file:

# Smart pane resizing with awareness of Vim splits.
# See: https://github.com/RyanMillerC/better-vim-tmux-resizer
is_vim="ps -o state= -o comm= -t '#{pane_tty}' \
    | grep -iqE '^[^TXZ ]+ +(\\S+\\/)?g?(view|n?vim?x?)(diff)?$'"

# Edit values if you use custom resize_count variables
bind-key -n M-h if-shell "$is_vim" "send-keys M-h"  "resize-pane -L 10"
bind-key -n M-j if-shell "$is_vim" "send-keys M-j"  "resize-pane -D 5"
bind-key -n M-k if-shell "$is_vim" "send-keys M-k"  "resize-pane -U 5"
bind-key -n M-l if-shell "$is_vim" "send-keys M-l"  "resize-pane -R 10"

bind-key -T copy-mode-vi M-h resize-pane -L 10
bind-key -T copy-mode-vi M-j resize-pane -D 5
bind-key -T copy-mode-vi M-k resize-pane -U 5
bind-key -T copy-mode-vi M-l resize-pane -R 10

NOTE: If you use vim-tmux-navigator, you can omit the is_vim line since it should already be in your ~/.tmux.conf file.

TPM

If you'd prefer, you can use the Tmux Plugin Manager (TPM) instead of copying the snippet. When using TPM, add the following lines to your ~/.tmux.conf:

set -g @plugin 'RyanMillerC/better-vim-tmux-resizer'
run '~/.tmux/plugins/tpm/tpm'

Configuration

Custom Key Bindings

If you don't want the plugin to create any mappings, you can use the four provided functions to define your own custom maps. You will need to define custom mappings in your ~/.vimrc as well as update the bindings in tmux to match.

Vim

Add the following to your ~/.vimrc to define your custom maps:

let g:tmux_resizer_no_mappings = 1

nnoremap <silent> {Left-Mapping} :TmuxResizeLeft<CR>
nnoremap <silent> {Down-Mapping} :TmuxResizeDown<CR>
nnoremap <silent> {Up-Mapping} :TmuxResizeUp<CR>
nnoremap <silent> {Right-Mapping} :TmuxResizeRight<CR>

NOTE: Each instance of {Left-Mapping} or {Down-Mapping} must be replaced in the above code with the desired mapping. Ie, the mapping for <meta-h> => Left would be created with nnoremap <silent> <meta-h> :TmuxResizeLeft<cr>.

Window Resize Counts

If the default increments for resizing do not suit your taste, you can configure this plugin to resize by specific increments both horizontally and vertically. These are configured with two variables in your ~/.vimrc file.

For horizontal resizing, set:

let g:tmux_resizer_resize_count = 5

For vertical resizing, set:

let g:tmux_resizer_vertical_resize_count = 10

Tmux

Alter each of the four lines of the tmux configuration listed above to use your custom mappings. Note each line contains two references to the desired mapping.

Troubleshooting

Vim -> Tmux doesn't work!

This is likely due to conflicting key mappings in your ~/.vimrc. You can use the following search pattern to find conflicting mappings \vn(nore)?map\s+\<c-[hjkl]\>. Any matching lines should be deleted or altered to avoid conflicting with the mappings from the plugin.

Another option is that the pattern matching included in the .tmux.conf is not recognizing that Vim is active. To check that tmux is properly recognizing Vim, use the provided Vim command :TmuxNavigatorProcessList. The output of that command should be a list like:

Ss   -zsh
S+   vim
S+   tmux

If you encounter a different output please open an issue with as much info about your OS, Vim version, and tmux version as possible.

Tmux Can't Tell if Vim Is Active

This functionality requires tmux version 1.8 or higher. You can check your version to confirm with this shell command:

tmux -V # should return 'tmux 1.8'

It Doesn't Work in tmate

tmate is a tmux fork that aids in setting up remote pair programming sessions. It is designed to run alongside tmux without issue, but occasionally there are hiccups. Specifically, if the versions of tmux and tmate don't match, you can have issues.

See this issue from vim-tmux-navigator for more detail.

It Still Doesn't Work!!!

The tmux configuration uses an inlined grep pattern match to help determine if the current pane is running Vim. If you run into any issues with the resize not happening as expected, you can open an issue here.