replace graal with karate-js engine

[ptrthomas]

refer: https://github.com/karatelabs/karate-js for full background

this will give us the following advantages:

• reduce JAR size by at least 30 MB if not more
• no limits to re-using JS code, even by call-once and call-single
• no more depending on 3rd party project (fewer CVEs and less risk in case that project changes direction)
• possibly improve performance
• foundation for extending karate in the future (e.g. an alternative to cucumber for those who want BDD)
• support debugging of even JS blocks in IDE plugins

[ptrthomas]

the build passes on github-actions (that too on Java 23 EA) 🎉

this is a very big deal ! tagging a few power users, please do try this on your local test suites when you get a chance, the thing to look out for is if you have used any JS apis or tricks that we don't yet support @edwardsph @ericdriggs @joelpramos @brown-kaew @fabio-andre-rodrigues @rwong-gw @cl-weclapp @AKushWarrior @bouncysteve @bondar-artem @f-delahaye @dvargas46 @maxandersen @arnault01 @jkeys089 @bischoffdev @staffier

this is the issue that tipped me over the edge: #2536

full changeset: https://github.com/karatelabs/karate/commit/ba931c8a5b9c1690f923638ff34fe27167f68eee

[maxandersen]

very interesting - will try it out.

I have to ask - why not just use and possibly fork nashhorn standalone? https://github.com/openjdk/nashorn ..maybe as an option?

anyhow - just curious. will see if i can make karata with this PR run jbang testsuite in near future.

[ptrthomas]

@maxandersen pretty sure Nashorn does not support some ES6 features - the big one being arrow-functions. I could be wrong on specifics, but it certainly fails the small set of ECMA conformance tests that we tried. Interestingly there are some folks who are keeping Rhino alive - for e.g. the HTMLUnit project who are now looking for new engine.

[ericdriggs]

Thank you for directly addressing this risk. I look forward to the potential improvements in speed, performance, concurrency, flakiness, and reduced maintenance and reduced frequency of breaking js engine changes.

Excellent start.

[woess]

pretty sure Nashorn does not support some ES6 features - the big one being arrow-functions

Basic arrow functions are supported (in --language=es6 mode).