This appeared to have been fixed. The above now generate the right results.

The description was updated.

Thanks, the actual author reference solution was wrong, but it passed the fixed cases. It was updated.

Can confirm - the reference solution doesn't check that the stack is empty before returning.

Got the following test case when attempting full suite with JS:

didn't work on the following argument array: ()()((() - Expected: true, instead got: false

There are also four hidden test cases that are marked as false but the test value is hidden. Based on the above, I don't trust that these cases are accurate.