Minimising plugin code for sbt

gistfile1.scala

object JSHintPlugin extends NodeJsPlugin {

  object JshintKeys {

    val jshint = TaskKey[Unit]("jshint", "Perform JavaScript linting.")

    val jshintOptions = TaskKey[String]("jshint-options", "An array of jshint options to pass to the linter. This options are found via jshint-resolved-config. If there is no config then the options will be specified such that the JSHint defaults are used.")

    val config = SettingKey[Option[File]]("jshint-config", "The location of a JSHint configuration file.")
    val resolvedConfig = TaskKey[Option[File]]("jshint-resolved-config", "The actual location of a JSHint configuration file if present. If jshint-config is none then the task will seek a .jshintrc in the project folder. If that's not found then .jshintrc will be searched for in the user's home folder. This behaviour is consistent with other JSHint tooling.")

  }

  import WebKeys._
  import JshintKeys._

  implicit val opInputHasher =
    OpInputHasher[File](source => OpInputHash.hashString(source + "|" + jshintOptions))

  def jshintSettings = nodeJsSettings ++ Seq(

    config := None,
    resolvedConfig := {
      config.value.orElse {
        val JsHintRc = ".jshintrc"
        val projectRc = baseDirectory.value / JsHintRc
        if (projectRc.exists()) {
          Some(projectRc)
        } else {
          val homeRc = file(System.getProperty("user.home")) / JsHintRc
          if (homeRc.exists()) {
            Some(homeRc)
          } else {
            None
          }
        }
      }: Option[File]
    },
    jshintOptions := {
      resolvedConfig.value
        .map(config => IO.read(config))
        .getOrElse("{}"): String
    },

    jshint in Assets := jsTask(Assets, jsFilter, jshintOptions, "JavaScript linting"),
    jshint in TestAssets := jsTask(TestAssets, jsFilter, jshintOptions, "JavaScript test linting"),

    compile in Compile := (compile in Compile).dependsOn(jshint in Assets).value,
    test in Test := (test in Test).dependsOn(jshint in Assets, jshint in TestAssets).value

  )

}

gistfile2.js

/*global process, require */

/*
 * Lint a number of files.
 *
 * Arguments:
 * 0 - name given to the command invoking the script (unused)
 * 1 - filepath of this script (unused)
 * 2 - array of file paths to the files to lint
 * 3 - jshint options as a Json object
 *
 * Json array tuples are sent to stdout for each file in error (if any). Each tuple is an array where the
 * element 0 corresponds to the file path of the file linted, and element 1 is JSHINT.errors.
 */

(function () {

    "use strict";

    var args = process.argv;
    var console = require("console");
    var fs = require("fs");
    var jshint = require("jshint");

    var SOURCE_FILE_PATHS_ARG = 2;
    var OPTIONS_ARG = 3;

    var options = JSON.parse(args[OPTIONS_ARG]);

    var sourceFilePaths = JSON.parse(args[SOURCE_FILE_PATHS_ARG]);
    var sourceFilesToProcess = sourceFilePaths.length;
    var results = [];
    var problems = [];
    sourceFilePaths.forEach(function (sourceFilePath) {
        fs.readFile(sourceFilePath, "utf8", function (e, source) {
            if (e) {
                console.error("Error while trying to read " + source, e);
            } else {
                var status = jshint.JSHINT(source, options);
                results.push({
                    source: sourceFilePath, 
                    result: status ? null : {filesRead: [sourceFilePath], filesWritten: []}
                });
                jshint.JSHINT.errors.forEach(function(e) {
                    problems.push({
                        message: e.reason,
                        severity: e.id.substring(1, e.id.length - 1),
                        lineNumber: e.line,
                        characterOffset: e.character - 1,
                        lineContent: e.evidence,
                        source: sourceFilePath
                    });
                });
            }
            if (--sourceFilesToProcess === 0) {
                console.log(JSON.stringify({results: results, problems: problems}));
            }
        });
    });
}());