Scala.js contains a reimplementation of part of the JDK in Scala.js itself.
To contribute to this code, it is strictly forbidden to even look at the source code of the Oracle JDK or OpenJDK!
This is for license considerations: these JDKs are under a GPL-based license, which is not compatible with our BSD 3-clause license.
It is also recommended not to look at any other JDK implementation (such as Apache Harmony), to minimize the chance of copyright debate.
Scala.js is entirely built with sbt, and also requires Node.js to be installed. For complete support, Node.js >= 10.0.0 is required.
The first time, or in the rare events where package.json
changes
(history),
you need to run
$ npm install
from your shell. If you really do not want to do this, you can avoid that
step, but you will need to use
set MyScalaJSPlugin.wantSourceMaps in testSuite := false
within sbt to
by-pass source-map-related tests. In addition, bootstrap tests will not pass.
Otherwise, everything happens within sbt.
Run the normal test suite using the entire Scala.js toolchain using
> testSuite/test
In order to test the tests themselves, run the cross-compiling tests on the JVM with:
> testSuiteJVM/test
If you have changed the IR or the compiler, you typically need to
> clean
before testing anew.
If you have changed the IR, the linker, the JS environments, the test adapter or the sbt plugin, you typically need to
> reload
To test in fullOpt stage:
> set scalaJSStage in Global := FullOptStage
There are also a few additional tests in a separate testing project:
> testSuiteEx/test
The compiler tests (mostly verifying expected compile error messages) can be run with
> compiler/test
The full partest suite (tests of the Scala language, ported in Scala.js) are run with:
> partestSuite/test
or, more typically,
> partestSuite/testOnly -- --fastOpt
The JUnit tests from scala/scala can be run with
> scalaTestSuite/test
If you want to develop in Eclipse, use sbteclipse. Projects as created by the build by default are not suited for Eclipse. You can create somewhat appropriate projects with:
$ GENERATING_ECLIPSE=true sbt "eclipse with-source=true"
You will still have to fix a few things:
- Uncheck the "Allow output directories per source directory" in Build path
- Add transitive project dependencies in Build path
The repository is organized as follows:
ir/
The Intermediate Representation, produced by the compiler and consumed by the linkercompiler/
The scalac compiler pluginio/
Virtual I/O abstractionslogging/
A tiny logging APIlinker/
The linker, optimizer, verifier, etc.: everything that happens at link time
library/
The Scala.js standard library (everything insidescala.scalajs.*
)javalanglib/
Implementation in Scala.js of the classes injava.lang.*
javalib/
Implementation in Scala.js of other classes injava.*
scalalib/
Almost void project for recompiling the Scala library for Scala.jslibrary-aux/
A few files of the Scala library that need to be compiled separately
All of these are packaged in scalajs-library.jar
.
The JS environments are JVM libraries that abstract the details of using a JavaScript engine to run JS code.
js-envs/
The generic definitions of JavaScript environments and runnersnodejs-env/
The Node.js environment
Other JS environments are developed in separate repositories under the
scala-js
organization.
There is a generic infrastructure that maps the sbt-testing-interface API across the JVM/JS boundary, so that Scala.js testing frameworks can be piloted from JVM processes such as sbt.
test-interface/
JS side of the bridge, as well as the JS definition of the sbt-testing-interface APItest-adapter/
JVM side of the bridge
This repository also contains a specific implementation of JUnit:
junit-runtime/
The run-time library for JUnitjunit-plugin/
The JUnit compiler plugin
sbt-plugin/
The sbt plugin itself
test-suite/
The main test suite of Scala.jstest-suite-ex/
Additional testspartest-suite/
The partest suite of Scalascala-test-suite/
The JUnit suite of Scala
examples/helloworld/
A simple Hello World, typically used as sandbox for quick testingexamples/reversi/
The historical Reversi demo - we use it to track the impact of changes on the emitted code sizeexamples/testing/
A simple project with tests using the DOM, mostly used to testtestHtml
with DOM interaction
The helloworld and reversi also have HTML pages to run them in real browsers.
The build itself contains the entire sbt plugin (and all its dependencies) as
part of its sources.
If you change any of the IR, virtual IO, logging API, linker, JS environments,
test adapter, or the sbt plugin itself, chances are you need to reload
the
build for your changes to take effect.
To publish your changes locally to be used in a separate project, use the
following incantations.
SCALA_VERSION
refers to the Scala version used by the separate project.
> ++SCALA_VERSION
> ;compiler/publishLocal;library/publishLocal;testInterface/publishLocal;testBridge/publishLocal;jUnitRuntime/publishLocal;jUnitPlugin/publishLocal
> ++2.10.7
> ;ir/publishLocal;io/publishLocal;logging/publishLocal;linker/publishLocal;jsEnvs/publishLocal;jsEnvsTestKit/publishLocal;nodeJSEnv/publishLocal;testAdapter/publishLocal;sbtPlugin/publishLocal