0.11.3 • Public • Published


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    ECMAScript code beautifier/formatter.


    This tool is still missing support for many important features. Please report any bugs you find, the code is only as good as the test cases. Feature requests are very welcome.

    We are looking for contributors!!

    Why? doesn't have enough options and not all IDEs/Editors have a good JavaScript code formatter. I would like to have a command line tool (and standalone lib) at least as powerful/flexible as the WebStorm and FDT code formatters so that it can be plugged into any editor and reused by other tools like escodegen.

    For more reasoning behind it and history of the project see: esformatter & rocambole


    This tool uses rocambole and babylon to recursively parse the tokens and transform it in place.


    • granular control about white spaces, indent and line breaks.
    • command line interface (cli).
    • be non-destructive.
    • support for local/global config file so settings can be shared between team members.
    • be extensive (plugins and other cli tools).
    • support most popular style guides through plugins (Google, jQuery, Idiomatic.js).
    • be the best JavaScript code formatter!


    var esformatter = require('esformatter');
    var fs = require('fs');
    var codeStr = fs.readFileSync('path/to/js/file.js').toString();
    // for a list of available options check "lib/preset/default.js"
    var options = {
      indent : {
        value : '  '
      lineBreak : {
        before : {
          // at least one line break before BlockStatement
          BlockStatement : '>=1',
          // only one line break before DoWhileStatementOpeningBrace
          DoWhileStatementOpeningBrace : 1,
          // ...
      whiteSpace : {
        // ...
    // return a string with the formatted code
    var formattedCode = esformatter.format(codeStr, options);

    See the doc/ file for a list of all the public methods and detailed documentation about each one.

    See doc/ for more info about the configuration options.


    You can also use the simple command line interface to process the stdin or read from a file.

    npm install [-g] esformatter


    Pass the --help flag to see the available options or see doc/cli.txt.

    esformatter --help


    # Format 
    # ====== 
    # format "test.js" and output result to stdout 
    esformatter test.js
    # you can also pipe other shell commands (read file from stdin) 
    cat test.js | esformatter
    # format "test.js" using options in "options.json" and output result to stdout 
    esformatter --config options.json test.js
    # process "test.js" and writes to "test.out.js" 
    esformatter test.js > test.out.js
    # you can override the default settings, see lib/preset/default.js for 
    # a list of available options 
    esformatter test.js --indent.value="\t" --lineBreak.before.IfStatementOpeningBrace=0
    # format "test.js" and output result to "test.js" 
    esformatter -i test.js
    # format and overwrite all the ".js" files inside the "lib/" folder 
    esformatter -i 'lib/*.js'
    # format and overwrite all the ".js" files inside "lib/" and it's subfolders 
    esformatter -i 'lib/**/*.js'
    # **important:** surround the glob with single quotes to avoid expansion; [glob 
    # syntax reference]( 
    # Diff 
    # ====== 
    # check if "test.js" matches style and output diff to stdout 
    esformatter --diff test.js
    # check if "test.js" matches style and output unified diff to stdout 
    esformatter --diff-unified test.js
    # check if "test.js" matches "options.json" style and output diff to stdout 
    esformatter --diff --config options.json test.js
    # check all files inside "lib/" and it's subfolders 
    esformatter --diff 'lib/**/*.js'

    Local version

    If a locally installed esformatter is found, the CLI uses that instead of the global executable (this means you can have multiple projects depending on different versions of esformatter).

    protip: add esformatter and all the plugins that you need on your project to the package.json devDependencies that way you can use locally installed plugins and also make sure everyone on your team is using the same version/settings.

      "devDependencies": {
        "esformatter": "~0.6.0",
        "esformatter-quotes": "^1.0.1"
      "esformatter": {
        "plugins": ["esformatter-quotes"],
        "quotes": {
          "type": "single"

    IDE / Editor integration

    Since esformatter is available as a command-line tool, it can be used in any editor that supports external shell commands.


    See doc/


    Presets are reusable config files that can require other presets/plugins and override configs.

      // presets are used as "base settings"
      "extends": [
        "preset:foobar", // load "esformatter-preset-foobar" from "./node_modules"
        "./lorem_ipsum.json" // load relative config file
      // you can still override any setting from the preset if needed
      "indent": {
        "value": "  "

    For more info see

    Pipe other CLI tools

    Since we don't expect everyone to write plugins that only works with esformatter we decided to encourage the usage of standalone CLI tools.

      // pipe is a simple way to "pipe" multiple binaries input/output
      "pipe": {
        // scripts listed as "before" will be executed before esformatter
        // and will forward output to next command in the queue
        "before": [
          "./bin/ --foo true -zx"
        // scripts listed as "after" will be executed after esformatter
        "after": [
          "baz --keepLineBreaks"


    Plugins are automatically loaded from node_modules if you pass the module id in the config file:

      "plugins": [ "esformatter-sample-plugin", "foobar" ]

    List of plugins and plugins wish list:

    List of plugins with easy filterable search:

    For detailed information about plugins structure and API see doc/


    We have an IRC channel #esformatter on for quick discussions about the project development/structure.


    See project Wiki for more info:

    Project structure / Contributing


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    Released under the MIT license


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