Empty case clauses ignored in switch statements

[Alhadis]

GraalJS doesn't branch to an empty case clause if there's a default specified. For example:

let value = 2;
switch(value){
    default:
        console.log("Default");
        break;
    case 1:
        console.log("One");
        break;
    case 2:
}

In other JS engines, this script will (correctly) output nothing. In GraalJS, however, it prints "Default" as if case 2 didn't match. Note that adding a break statement changes this:

 let value = 2;
 switch(value){
    default:
        console.log("Default");
        break;
    case 1:
        console.log("One");
        break;
    case 2:
+       break;
 }

[iamstolis]

Thank you for the report! Yes, this looks like a bug in GraalJS. It seems that we "overoptimize" the empty case.

[iamstolis]

Fixed by https://github.com/graalvm/graaljs/commit/bec8d9eea00cb140f3c6ec8aaab9fbd853de191a