difference in behaviour with import module java.base

[Max Rydahl Andersen]

Hi,

I got reported a "fun" issue on jbang
https://github.com/jbangdev/jbang/issues/2072 which boils down to the
following calls to jshell behaving differently for reasons I can't really
explain.

I've boiled it down to what *looks* like a bug/change of behaviour and
wondering if intentional or not:

Take this code and put in test.jsh (you can also manually type it but whats
the fun in that):

String[] args = { "arg1", "arg2" }
import module java.base;
import static java.util.stream.Collectors.*;
System.out.println(args.length);
/exit

now run this using:

jshell --enable-preview -J--enable-preview --startup=DEFAULT
--execution=local test.jsh

And you will get printed:
2

the correct length of the args array.

Now change it to:

String[] args = { "arg1", "arg2" }
import static java.util.stream.Collectors.*;
import module java.base;
System.out.println(args.length);
/exit

Note, the import order is changed.

Now you get:

WARNING: Using incubator modules: jdk.incubator.vector
Exception java.lang.NullPointerException: Cannot read the array length
because "REPL.$JShell$11B.args" is null
      at (#4:1)

question is why is this happening?

Also, if you remove `--startup=DEFAULT` OR `--execution=local` the
behaviour stays the same and 2 is printed in all cases.

Bug or expected ?

Hope it all makes sense :)

-- 
/max
https://about.me/maxandersen
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