Zsh ships vcs_info, a function fetching information about theVCS state for the current directory and populating a variable that canbe used in a shell prompt. It supports several VCS, including Git andSVN. Here is an example of configuration:
autoload -Uz vcs_infozstyle ':vcs_info:*' enable git() { local formats="${PRCH[branch]} %b%c%u" local actionformats="${formats}%{${fg[default]}%} ${PRCH[sep]} %{${fg[green]}%}%a" zstyle ':vcs_info:*:*' formats $formats zstyle ':vcs_info:*:*' actionformats $actionformats zstyle ':vcs_info:*:*' stagedstr "%{${fg[green]}%}${PRCH[circle]}" zstyle ':vcs_info:*:*' unstagedstr "%{${fg[yellow]}%}${PRCH[circle]}" zstyle ':vcs_info:*:*' check-for-changes true}add-zsh-hook precmd vcs_info
You can use ${vcs_info_msg_0_} in your prompt to display the currentbranch, the presence of staged and unstaged changes, as well as theongoing action.1 Have a look at the documentation for moredetails.
On large repositories, some information are expensive to fetch. Whilevcs_info queries Git, interactions with Zsh are stuck. A possiblesolution is to execute vcs_info asynchronously with zsh-async.
The first step is to define a wrapper around vcs_info. Thiswrapper will run into a separate process and should communicate itsresult using the standard output. It expects the current directory asits first argument.
_vbe_vcs_info() { cd -q $1 vcs_info print ${vcs_info_msg_0_}}
The second step is to define a worker, vcs_info, and attach afunction to handle the result received from the wrapper. Theregistered function calls zle reset-prompt to force a refresh of theprompt with the updated information from ${vcs_info_msg_0_}.
source $ZSH/.../async.zshasync_initasync_start_worker vcs_infoasync_register_callback vcs_info _vbe_vcs_info_done_vbe_vcs_info_done() { local stdout=$3 vcs_info_msg_0_=$stdout zle reset-prompt}
The last step is to schedule the wrapper function in the workerqueue before displaying the prompt. This replaces the synchronousinvocation of vcs_info:
_vbe_vcs_precmd() { async_flush_jobs vcs_info async_job vcs_info _vbe_vcs_info $PWD}add-zsh-hook precmd _vbe_vcs_precmd
That’s it!
Without relying on vcs_info, it should be possible to have a betterexperience by fetching the current branch name before retrieving themore expensive information. However, without much effort, this simpleintegration can make your prompt snappier! Have a look at thecomplete code: it contains some small enhancements.
Actions include “merge,” “rebase” and “bisect.”↩︎
