Honor scalar context for sort returned from a subroutine

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#1,991 1 comentario 0 reacciones 0 asignados Ver en GitHub

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@fglock ya está trabajando en esto.

Desde el 6/11/2026.

  • #1992 de @fglock — abierto

Evaluación

Dificultad
3/5
Tiempo estimado
1-2 días
Aptitud para principiantes
25/100
Tipo de issue
Error
Claridad
Bien especificado
Estado de actividad
Estancado
Stack tecnológico
perl
Área
backend

Línea de trabajo

Start by reviewing PR #1992, which is already open and describes the fix across the JVM and interpreter backends. Trace how a subroutine return passes runtime context to sort, then run the focused regression and scalar-sort tests on both backends. Done means scalar callers receive Perl's undef result while list behavior remains covered.

Escrito por el modelo de indexación a partir del texto del issue.

Descripción

area:runtime bug

Summary

sort in a subroutine return did not honor the caller's scalar context. Perl returns undef for sort in scalar context, but PerlOnJava returned the number of sorted values. This broke DataCube 0.01's tables method, which returns sort keys ... and is called in scalar context by its test suite.

Minimal reproducer

sub f { return sort qw(a b c) }
my $x = f();
print defined($x) ? "<$x>\n" : "undef\n";

Expected under system Perl: undef

Before the fix, PerlOnJava returned <3> on both JVM and interpreter backends.

Evidence

  • CPAN distribution: DataCube 0.01; random tester run 20261106-154847-45334.
  • System Perl 5.42.2: upstream make test passed, 26 tests.
  • PerlOnJava 5.44.1, build commit 13db7bd4a0: t/00_use.t exited 255 on both JVM and interpreter after 15 assertions, with Can't use string ("40") as a HASH ref.
  • The DataCube test assigns $cube->tables to a scalar. DataCube::tables returns sort keys ...; the scalar result was then treated as a hash reference.

Confirmed cause and fix

Static scalar-context sort was already handled. In a subroutine return, however, the caller's context is dynamic: PerlOnJava retained the sorted list and generic return handling scalarized it to the list length. PR #1992 passes the runtime context to sort on both backends, preserving input evaluation while skipping the comparator and returning undef for a scalar caller.

The focused regression and existing scalar-sort tests pass on system Perl, JVM, and interpreter. The full repository make and documentation link check pass. The DataCube suite progresses beyond the former failure, but later tests exceed the bounded 180-second runs; a full post-fix DataCube suite pass is not claimed.

Lenguaje dominante
Perl
Estrellas
65
Forks
8
Merge medio
5 h 57 min
PR fusionados (30 d)
177

Preparar el entorno

Primeros pasos

  1. Lee el issue completo y luego la guía de contribución del proyecto.
  2. Comenta en el issue que vas a ocuparte — evita que dos personas hagan lo mismo.
  3. Haz un fork del repositorio y trabaja en una rama.
  4. Abre un pull request que haga referencia al número del issue.

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