From @usev6

Some of the newly added tests for IO​::Handle.open with different
modes fail on the JVM backend. The basic modes (​:r, :w, :x, :a) and
combinations of those do work as expected, but there are problems
with :append and :create and :ra.

Just now I found rakudo/rakudo@36f773eb01
where those modes where added (I only looked at docs.perl6.org
before). From the commit message I learned​:

  :append was not meant as a synonym for :a

  :ra was not meant to stand for "read + append"

  :r, :a was not meant to stand for "read + append"

The first one surprised me the most. But indeed :a and :append work
differently​:

  $ rm -f foo 2>/dev/null; ./perl6-m -e '"foo".IO.open(​:a)'; ls -s foo
  0 foo

  $ rm -f foo 2>/dev/null; ./perl6-m -e '"foo".IO.open(​:append)'; ls -s foo
  Failed to open file /path/to/rakudo.moar/foo​: no such file or directory
  in block <unit> at -e line 1

  Actually thrown at​:
  in block <unit> at -e line 1

  ls​: foo​: No such file or directory

What poses a problem for rakudo-j is, that :append and :create
(without :w) are assumed to mean "read" with Java and those
combinations (append + read) and (create + read) do not work well. [2]

IMHO a clarification is needed. If we want the additional modes as
described in rakudo commit 36f773eb01 (and as implemented, bugs
notwithstanding) then we should

* define that :append and :create always imply "write"

* change the implementation for the JVM backend so that the newly
  added tests pass

* expand the documentation of "open"

See also the discussion on #perl6-dev​:
https://irclog.perlgeek.de/perl6-dev/2017-04-13#i_14424307

[1] https://docs.oracle.com/javase/8/docs/api/java/nio/channels/FileChannel.html#open-java.nio.file.Path-java.util.Set-java.nio.file.attribute.FileAttribute...-

From @usev6

On Thu, 13 Apr 2017 12​:21​:57 -0700, bartolin@​gmx.de wrote​:

[...]
* expand the documentation of "open"

That was done by Zoffix++ with Raku/doc@ca2a3a0bfb

@usev6 - Status changed from 'new' to 'open'

From @usev6

On Thu, 13 Apr 2017 12​:21​:57 -0700, bartolin@​gmx.de wrote​:

[...]
* define that :append and :create always imply "write"

That was also done by Zoffix++ -- mainly with Raku/roast@091931a717

From @usev6

On Sat, 10 Mar 2018 11​:40​:24 -0800, bartolin@​gmx.de wrote​:

On Thu, 13 Apr 2017 12​:21​:57 -0700, bartolin@​gmx.de wrote​:

[...]
* define that :append and :create always imply "write"

That was also done by Zoffix++ -- mainly with
Raku/roast@091931a717

Sorry, that comment wasn't clear. What I meant was, that the different open modes were specced in S32-io/open.t with said commit.

From @usev6

On Thu, 13 Apr 2017 12​:21​:57 -0700, bartolin@​gmx.de wrote​:

[...] then we should

* change the implementation for the JVM backend so that the newly
added tests pass

The tests for open modes are passing now on the JVM backend. I'm closing this ticket as 'resolved'.

@usev6 - Status changed from 'open' to 'resolved'