Lesser-watch NPM

lesser-watch

watch LESS files and selectively recompiles them whenever (directly or indirectly) @import-ed files change

Motivation

This package provides a smarter way to watch LESS files.

If you like your stylesheets to be DRY and modular, you'll ave a deep dependency graph of file imported by multiple other files.

Yet not all of the stylesheets will import a file.

So you can watch your entire styles/ directory and recompile all of your "root" files everytime something changes (which is unefficient if you have a large codebase and literally hell if you use something like livereload), or you can do it better by selectively recompile only those "root" files which are affected by the change. This is exactly what lesser-watch does.

Installation

$ npm install lesser-watch --save-dev

This is a CLI tool, so you might want it installed globally.

Anyway, lesser-watch expects LESS to be installed in the same directory it is installed, be it local or global.

Usage

Get usage information by running lesser-watch --help:

lesser-watch <command> [options]

Commands:
  lesser-watch  watch LESS files and selectively recompiles them whenever (directly or indirectly) @import-ed files change

Options:
  --version      Show version number  [boolean]
  -h, --help     Show help  [boolean]
  -c, --command  The command to execute to recompile a file.
                 The command will receive the file contents from stdin and its stdout will get piped to the output file
                 Useful if you have a non-trivial build pipeline (e.g. 'lessc - | postcss') or if you need to provide options to LESS. If you need to provide the source filename as an argument, the env variable SOURCE_FILE_PATH will be set to that when calling the provided command.
				         [default: "node_modules/.bin/lessc -"]
  -e, --entries  Entry files. Any of them will recompile if one of its direct or indirect dependencies gets updated
                 [array] [required]
  -d, --dest     Destination folder. Compiled files are put here
                 [required]
  -p, --polling  If set to 0, disable polling. Otherwise, watch with polling using the interval provided (in milliseconds)
                 [default: 0]

Examples:
  lesser-watch -c 'lessc --source-map-map-inline -x' -e main.less -d static

  Watch main.less dependencies and recompile with flags --source-map-map-inline and -x


  lesser-watch -c 'lessc --source-map-map-inline | postcss --map | exorcist static/`basename $SOURCE_FILE_PATH`.map' -e main.less critical.less -d static

  Watch main.less and critical.less. Recompile creating sourcemaps and then save them as main.less.map and critical.less.map

The underlying watching is done by the awesome chokidar. The CLI logic is handled by the even more awesome yargs.