From @usev6

Today I got a failure while spectesting for rakudo.jvm​:

Failure summary​:
S02-names-vars/perl.rakudo.jvm 84 - .perl on user-defined type roundtrips okay

I investigated and the test in question runs fine most of the time but fails only once in a while. The test in question is on the last line of following code​:

# RT #​61918
#?niecza skip ">>>Stub code executed"
{
  class RT61918 {
  has $.inst is rw;
  has $!priv;
  has $.string = 'krach';

  method init {
  $.inst = [ rand, rand ];
  $!priv = [ rand, rand ].perl;
  }
  }

  my $t1 = RT61918.new();
  my $t1_new = $t1.perl;
  $t1.init;
  my $t1_init = $t1.perl;

  ok $t1_new ne $t1_init, 'changing object changes .perl output';

  # TODO​: more tests that show EVAL($t1_init) has the same guts as $t1.
  ok $t1_new ~~ /<< krach >>/, 'attribute value appears in .perl output';

  # RT #​62002 -- validity of default .perl
  my $t2_init = EVAL($t1_init).perl;
  is $t1_init, $t2_init, '.perl on user-defined type roundtrips okay';
}

To me it looks as if "rand" (in method "init") sporadically generates values that don't survive the roundtrip on JVM. I tried to reproduce the failure and eventually came up with an example​:

$ perl6-j -e 'my $a = 0.219947518065601987e0; say $a.perl; say EVAL($a.perl).perl'
0.21994751806560198e0
0.219947518065602e0

Moar and Parrot return less decimal places for $a.perl already​:

$ perl6-m -e 'my $a = 0.219947518065601987e0; say $a.perl; say EVAL($a.perl).perl'
0.219947518065602e0
0.219947518065602e0

So .perl behaves differently in this case on JVM and Moar/Parrot.

Maybe I'm looking in the wrong direction, but the test failure should not occur. I'm going to fudge the test ('skip') for rakudo.jvm.

From @moritz

Hi,

On 10/24/2014 06​:16 PM, Christian Bartolomaeus (via RT) wrote​:

# New Ticket Created by Christian Bartolomaeus
# Please include the string​: [perl #​123048]
# in the subject line of all future correspondence about this issue.
# <URL​: https://rt-archive.perl.org/perl6/Ticket/Display.html?id=123048 >

Today I got a failure while spectesting for rakudo.jvm​:

Failure summary​:
S02-names-vars/perl.rakudo.jvm 84 - .perl on user-defined type roundtrips okay

I investigated and the test in question runs fine most of the time but fails only once in a while. The test in question is on the last line of following code​:

# RT #​61918
#?niecza skip ">>>Stub code executed"
{
class RT61918 {
has $.inst is rw;
has $!priv;
has $.string = 'krach';

     method init \{
         $\.inst = \[ rand, rand \];
         $\!priv = \[ rand, rand \]\.perl;
     \}
 \}

 my $t1 = RT61918\.new\(\);
 my $t1\_new = $t1\.perl;
 $t1\.init;
 my $t1\_init = $t1\.perl;

 ok $t1\_new ne $t1\_init, 'changing object changes \.perl output';

 \# TODO​: more tests that show EVAL\($t1\_init\) has the same guts as $t1\.
 ok $t1\_new ~~ /\<\< krach >>/, 'attribute value appears in \.perl output';

 \# RT #&#8203;62002 \-\- validity of default \.perl
 my $t2\_init = EVAL\($t1\_init\)\.perl;
 is $t1\_init, $t2\_init, '\.perl on user\-defined type roundtrips okay';

}

To me it looks as if "rand" (in method "init") sporadically generates values that don't survive the roundtrip on JVM. I tried to reproduce the failure and eventually came up with an example​:

$ perl6-j -e 'my $a = 0.219947518065601987e0; say $a.perl; say EVAL($a.perl).perl'
0.21994751806560198e0
0.219947518065602e0

Moar and Parrot return less decimal places for $a.perl already​:

$ perl6-m -e 'my $a = 0.219947518065601987e0; say $a.perl; say EVAL($a.perl).perl'
0.219947518065602e0
0.219947518065602e0

So .perl behaves differently in this case on JVM and Moar/Parrot.

Maybe I'm looking in the wrong direction, but the test failure should not occur. I'm going to fudge the test ('skip') for rakudo.jvm.

The better approach is to isolate the user-defined type roundtrips test
from roundtripping floats with many digits.

So rather remove the rand's, replace them by fixed values, and have
separate tests for round-tripping 0.21994751806560198e0. Then fudge that
test for JVM as needed.

Cheers,
Moritz

The RT System itself - Status changed from 'new' to 'open'

From @usev6

Hi,

On Mon Oct 27 02​:19​:48 2014, moritz wrote​:

[...]
To me it looks as if "rand" (in method "init") sporadically generates
values that don't survive the roundtrip on JVM. I tried to reproduce
the failure and eventually came up with an example​:

$ perl6-j -e 'my $a = 0.219947518065601987e0; say $a.perl; say
EVAL($a.perl).perl'
0.21994751806560198e0
0.219947518065602e0

Moar and Parrot return less decimal places for $a.perl already​:

$ perl6-m -e 'my $a = 0.219947518065601987e0; say $a.perl; say
EVAL($a.perl).perl'
0.219947518065602e0
0.219947518065602e0

So .perl behaves differently in this case on JVM and Moar/Parrot.

Maybe I'm looking in the wrong direction, but the test failure should
not occur. I'm going to fudge the test ('skip') for rakudo.jvm.

The better approach is to isolate the user-defined type roundtrips
test from roundtripping floats with many digits.

So rather remove the rand's, replace them by fixed values, and have
separate tests for round-tripping 0.21994751806560198e0. Then fudge
that test for JVM as needed.

Cheers,
Moritz

I did that with commit Raku/roast@2cba5c0ede
I'm gonna change the subject of this ticket accordingly.

Thanks for the suggestion!

Cheers,
Christian

From @usev6

The test in S02-names-vars/perl.t is passing now. I'm closing this ticket as 'resolved'.

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