XS is the JavaScript engine at the center of the Moddable SDK.

Please visit Moddable to get the source code, documentation and licence of XS

This repository only releases xst, a JavaScript engine to test XS on Linux, macOS and Windows and xsbug, the XS debugger.

You can use the jsvu CLI to install or update xst from this repostiory.

xst [-h] [-e] [-m] [-s] [-t] [-v] strings...

• -h: print this help message
• -e: eval strings
• -m: strings are paths to modules
• -s: strings are paths to scripts
• -t: strings are paths to test262 cases or directories
• -v: print XS version

without -e, -m, -s, or -t:

• if ../harness exists, strings are paths to test262 cases or directories
• else if the extension is .mjs, strings are paths to modules
• else strings are paths to scripts

To test XS with eshost, install the eshost CLI. Then add XS to the hosts:

eshost --add 'XS' xs ~/.jsvu/xst

eshost uses the -s option of xst.

To test XS with test262, clone test262 and change the directory to the test directory inside the test262 directory. For instance:

cd ~/test262/test
xst language/block-scope
xst built-ins/TypedArrays/buffer-arg-*

See XS Conformance for details about how XS currently passes test262 cases.

Running xsbug while passing a bunch of test262 cases can be cumbersome. Just quit xsbug or at least uncheck Break - On Exceptions in the preferences.

See the xsbug documentation in the Moddable SDK.