non-interactive REPL mode breaks STDIN

[zoffixznet]

$ perl6 <<< get                                                                                                                                                                                                
Failed to stat file descriptor: Bad file descriptor
  in block <unit> at - line 1

$ echo 'get' | perl6 -
MVMArray: Index out of bounds
  in block <unit> at - line 1

$ perl6 -v
This is Rakudo version 2018.03-265-g656ff77b9 built on MoarVM version 2018.03-126-g876aa90ee
implementing Perl 6.c.

And the cause is:

$ echo '$*IN.native-descriptor.say' | perl6 -
-1

And the fix is to stick unless $filename eq '-' for the .close line in NQP (a few lines up, we use the same condition to set that handle to stdin)

[uzluisf]

I already added:

unless $filename eq '-' {
     $in-handle.close;
}

in my local repo and running the same commands but I'm still getting the same output. I'm not sure what I should do next so any advice would be appreciated.

[zoffixznet]

Are you sure you rebuilt nqp and rakudo correctly? Which commands did you use?

[uzluisf]

I just used make and make install.

[zoffixznet]

Try this:

In your nqp dir:

make clean
make
make install

Then in your rakudo dir:

make clean
make
make install

That should make the fix available in your rakudo and fix the bug. You can then run:

make spectest

To run the spectest to ensure there are no new errors.

Alternatively, there's also Z-Script you could use:

Install and initialize in ~/R/:

    git clone https://github.com/zoffixznet/z ~/zscript &&
    cd ~/zscript &&
    zef --depsonly install .

    echo 'export PATH="$HOME/zscript/bin:$PATH"' >> ~/.bashrc
    . ~/.bashrc

    z init ~/R

Then swap nqp remote to your fork (you need to fork it. Click "Fork" button at the top right of the page):

    cd ~/R/nqp/
    git remote remove origin
    git remote add origin https://github.com/uzluisf/nqp

Then make the change, then run:

z n

That will rebuild NQP and rakudo and the change should fix the bug. Then you can run

z s

To run the spectest. Then commit the fix:

    cd ~/R/nqp
    git commit src/HLL/Compiler.nqp

Type a good commit message, then git push and then submit the PR on github.

[uzluisf]

So I ran the commands to rebuild nqp and rakudo and everything went apparently fine.

After that, I executed perl6 <<< get, echo 'get' | perl6 - and echo '$*IN.native-descriptor.say' | perl6 - to check if the fix took effect but I'm getting the same output you detailed in the issue.

[zoffixznet]

But is perl6 the rakudo you built or your system-installed one? In my builds, I have to use ./perl6 to run the one I built and running just perl6 without ./ runs the system one.

[uzluisf]

Yes, you're totally right. I was running the system's rakudo not the one I built. Sorry for that misunderstanding.

Regarding the commit message, can I reference the issue? I'm not really sure what I should put for the commit message.

[zoffixznet]

Regarding the commit message, can I reference the issue? I'm not really sure what I should put for the commit message.

Yeah, if you include a link to it, GitHub will even reference the commit on this Issue.

Message could be something like

Do not close STDIN it is the source of the program

Fixes https://github.com/rakudo/rakudo/issues/1824