Awesome

sbt-traceur

sbt-web plugin to compile ES6 to ES5 with traceur-compiler.

Changelog

Version	Changes
2.1.0	Upgrade traceur-compiler to v0.0.111.<br>Improve plugin by supporting all traceur-compiler options.
2.0.0	Upgrade traceur-compiler to v0.0.90.<br>Refactor plugin to use pipeline stage.
1.0.2	First try with Scala, sbt and Bintray. Experimental, don't use it!
1.0.1	Last version forked from arielscarpinelli/sbt-traceur

I decided to fork the sbt-web plugin of arielscarpinelli because I couldn't control traceur within the pipeline stage. You can now call traceur in the pipeline stage where ever you want.

How to use

You first need to add this resolver in your project's plugins.sbt file:

    resolvers += Resolver.bintrayRepo("rayshader", "sbt")

Then, add the dependency with the addSbtPlugin command:

    addSbtPlugin("rayshader" % "sbt-traceur" % "2.1.0")

Your project's build.sbt file also needs to enable sbt-web plugins:

    lazy val root = (project in file(".")).enablePlugins(SbtWeb)

Finally, you need to include the plugin into the pipeline stage like:

    pipelineStages := Seq(traceur)

NB: the plugin will remove .js files from the sourceDir path. As only the output file seems necessary. This is due to an issue encountered with sbt-uglify. If you want to keep these files in your pipeline you can turn off the option removeJs.

Example

You may want to compile ES6 to ES5, then minify javascript and concat everything. Let's say your main entry point of ES6 code is app.js. Then, you can minify app.js and traceur-runtime.js. Finally you can concat the whole to output a single main.min.js file:

    pipelineStages := Seq(traceur, uglify, concat)
    
    TraceurKeys.sourceDir := "js"
    TraceurKeys.outputDir := "js"
    TraceurKeys.sourceFiles := Seq("app.js")
    TraceurKeys.outputFile := "app.js"
    
    UglifyKeys.uglifyOps := UglifyOps.singleFile
    
    Concat.groups := Seq(
      "js/main.min.js" -> group(Seq("js/traceur-runtime.min.js", "js/app.min.js"))
    )

Configuration

All options are available within the object TraceurKeys. For example, to enable sourceMaps you'll do:

    import rayshader.traceur._
    
    TraceurKeys.sourceMaps := true

For option modules, you will found constants in the object TraceurModules.

For option moduleName, you will found constants in the object TraceurModuleName.

For example:

    import rayshader.traceur._
    
    TraceurKeys.modules := TraceurModules.AMD
    TraceurKeys.moduleName := TraceurModuleName.Named

Option	Description	Default
sourceDir	The relative path where your ES6 files are located.	`javascripts`
outputDir	The relative path where your compiled ES6 files will be located.	`javascripts`
useDir	If true will use the option `--dir in out` where `in` and `out` are `sourceDir` and `outputDir`.	`false`
sourceFiles	Relative paths of the files to compile. Should just be the 'root' module, traceur will pull the rest.	`Seq("main.js")`
outputFile	The name of the compiled file.	`main.js`
sourceMaps	Enable source maps generation.	`false`
experimental	Turns on all experimental features.	`false`
modules	Select the output format for modules between AMD, CommonJS, Closure, Instantiate, Inline, Bootstrap.	`Bootstrap`
moduleName	`Named` for named, `Anonymous` for anonymous modules; `Default` depends on `modules`.	`Default`
options	Provide extra options to traceur-compiler.
includeRuntime	If traceur-runtime.js code should be copied in the outputDir.	`true`
removeJs	Remove .js files from sourceDir within the pipeline.	`true`

How to test

First clone the project.
Use the command clean compile package publishLocal with sbt to compile and publish locally the plugin.
Use commands clean webStage within test/[NAME_OF_THE_TEST] directory to try the plugin.
Open index.html from src/main/assets/ directory.
Output section shall show some texts and display a green background.

Feel free to contribute for more features and bug fixes through issues :).