Redbush is a Neovim plugin for Clojure repls. It supports both nrepl and Clojure's own socket repl (clojure.core.server/io-prepl). Plugin itself is written in rust so it has almost instant startup time provided of course that you have nrepl/prepl-server up and running. Redbush uses neovim-lib for neovim integration.

Redbush supports very basic set of interactions with the repl (send forms to repl, receive and show evaluation results) and should be accompanied with other more specialized clojure-related plugins (e.g. for linting, documentation lookup, completion, etc.) to have more complete clojure development environment with neovim.

What makes redbush different from other similar neovim clojure-plugins? As redbush is written in rust it has fast and almost instant startup time and it has effortless/automatic support for both nrepl and prepl (clojure's standard socket repl). Those features were the main goals for redbush from the beginning.

While the basic functionality is considered done, redbush is still taking baby steps and it's definitely not yet battle-tested thoroughly.

Basic installation requires that you have rust and cargo installed in your system. Example installation using vim-plug:

Plug 'jasilven/redbush', { 'do': 'cargo install --path .' }

This fetches, compiles and installs the latest version of redbush binary executable using cargo (see https://doc.rust-lang.org/cargo/commands/cargo-install.html for details). Redbush binary executable is placed according to your cargo settings (typically in $HOME/.cargo/bin).

Example configuration with default values (.vimrc/init.vim):

let g:redbush_bin = 'redbush'
let g:redbush_filepath = '/tmp/redbush-eval.clj'
let g:redbush_filesize = 1000 
let g:redbush_is_vertical = v:true
let g:redbush_winsize = 40

• g:redbush_bin tells where the redbush binary is located. If it's not in your $PATH then full path is required.
• g:redbush_filepath file path/name of the redbush evaluation buffer, that is used to record and show REPL responses.
• g:redbush_filesize redbush evaluation buffer size in lines.
• g:redbush_is_vertical if this is v:true then evaluation buffer is shown as vertical split window in neovim otherwise horizontal.
• g:redbush_winsize evaluation buffer window size. For vertical window it's the width and for horizontal window it's the height of the evaluation buffer window.

You only need to configure those if you are not happy with the defaults.

First start your nrepl/prepl server however you wish. Here is an example of leiningen project.clj that will start both repls:

(defproject myproject "0.1"
  :dependencies [[org.clojure/clojure "1.10.0"]]
  :repl-options {:init (let [port (+ 6000 (rand-int 1000))]
                         (spit ".prepl-port" port)
                         (clojure.core.server/start-server {:accept 'clojure.core.server/io-prepl
                                                            :address "localhost"
                                                            :port port
                                                            :name "prepl"}))})

With the above project.clj in place in your project root run:

$ lein repl

Now you should have both nrepl and prepl available in different ports and the port numbers can be found inside the .nrepl-port and .prepl-port files accordingly.

There are several neovim commands available that you can use to interact with the plugin and the repl:

• RedBushStart starts redbush plugin which connects to the repl port if there is either .nrepl-port or .prepl-port file containing the repl port number in the current working directory. If both of the port-files are missing you should use RedBushConnect <port> to start redbush and connect it to the repl you wish.
• RedBushConnect <port> starts and connects redbush to the repl in port <port>. With RedBushConnect the .nrepl-port or .prepl-port files are ignored.
• RedBushRestart restart redbush.
• RedBushStop stop and exit redbush.

• RedBushEvalRange evaluate (visual) range.
• RedBushEvalForm evaluate surrounding clojure-form.
• RedBushEvalFile evaluate whole file.
• RedBushEvalFormTime evaluate surrounding clojure-form with clojure.core/time.

• RedBushToggle toggle evaluation buffer.

• RedBushRunTests run current namespace tests (using clojure.test/run-tests).

All of the above neovim-commands can be mapped as usual to keyboard shortcuts as you like.