perldb improperly handles blessed coderefs #23486
Description
Module: perldb
Description
When calling a blessed coderef as a sub, perldb requires both q{eq} and q{""} overloads, but passes a non-object to those methods.
Steps to Reproduce
Here's a simple class which triggers on a missing q{eq} overload:
use v5.10; package Bar { use Scalar::Util 'blessed'; use overload fallback => 0, bool => sub { 1 }, ; sub new { my $class = shift; return bless sub { 'foo' }, $class; } } say Bar->new->(); running under the debugger produces:
Operation "eq": no method found, left argument in overloaded package Bar, right argument has no overloaded magic at /home/dj/.plenv/versions/5.40/lib/perl5/5.40.0/perl5db.pl line 4475. at /home/dj/.plenv/versions/5.40/lib/perl5/5.40.0/perl5db.pl line 4475. Introducing an overload for q{eq}:
use v5.10; package Bar { use Scalar::Util 'blessed'; use overload fallback => 0, bool => sub { 1 }, eq => sub { say 'Class: ', blessed( $_[0] ) // '<no class>'; say 'Ref: ', ref $_[0]; !!0; }, ; sub new { my $class = shift; return bless sub { 'foo' }, $class; } } say Bar->new->(); results in
Class: <no class> Ref: CODE Operation """": no method found, argument in overloaded package Bar at /home/dj/.plenv/versions/5.40/lib/perl5/5.40.0/perl5db.pl line 4481. at /home/dj/.plenv/versions/5.40/lib/perl5/5.40.0/perl5db.pl line 4481. Strangely, the first argument passed to the overload sub is no longer an object, just a plain CODE ref.
Adding the q{""} operator gets through the debugger,
use v5.10; package Bar { use Scalar::Util 'blessed'; use overload fallback => 0, bool => sub { 1 }, eq => sub { say 'Class: ', blessed( $_[0] ) // '<no class>'; say 'Ref: ', ref $_[0]; !!0; }, q{""} => sub { say 'Class: ', blessed( $_[0] ) // '<no class>'; say 'Ref: ', ref $_[0]; 'Bar'; }, ; sub new { my $class = shift; return bless sub { 'foo' }, $class; } } say Bar->new->(); Class: <no class> Ref: CODE Class: <no class> Ref: CODE foo Debugged program terminated. Use q to quit or R to restart, With the same non-object passed to the q{""} overload sub.
Expected behavior
I think the debugger gets confused about coderefs which are blessed and makes assumptions about them which don't hold.
I expect that the debugger should handle blessed coderefs the same as ordinary coderefs and not require extra overloads from them (and if it does, that it passes the blessed object to them)
Perl configuration
Summary of my perl5 (revision 5 version 40 subversion 0) configuration: Platform: osname=linux osvers=6.9.7+bpo-amd64 archname=x86_64-linux uname='linux leafhopper 6.9.7+bpo-amd64 #1 smp preempt_dynamic debian 6.9.7-1~bpo12+1 (2024-07-03) x86_64 gnulinux ' config_args='-Dprefix=/home/dj/.plenv/versions/5.40 -de -Dversiononly -A'eval:scriptdir=/home/dj/.plenv/versions/5.40/bin'' hint=recommended useposix=true d_sigaction=define useithreads=undef usemultiplicity=undef use64bitint=define use64bitall=define uselongdouble=undef usemymalloc=n default_inc_excludes_dot=define Compiler: cc='cc' ccflags ='-fwrapv -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -D_FORTIFY_SOURCE=2' optimize='-O2' cppflags='-fwrapv -fno-strict-aliasing -pipe -fstack-protector-strong -I/usr/local/include' ccversion='' gccversion='12.2.0' gccosandvers='' intsize=4 longsize=8 ptrsize=8 doublesize=8 byteorder=12345678 doublekind=3 d_longlong=define longlongsize=8 d_longdbl=define longdblsize=16 longdblkind=3 ivtype='long' ivsize=8 nvtype='double' nvsize=8 Off_t='off_t' lseeksize=8 alignbytes=8 prototype=define Linker and Libraries: ld='cc' ldflags =' -fstack-protector-strong -L/usr/local/lib' libpth=/usr/local/lib /usr/lib/x86_64-linux-gnu /usr/lib /usr/lib64 libs=-lpthread -ldl -lm -lcrypt -lutil -lc perllibs=-lpthread -ldl -lm -lcrypt -lutil -lc libc=/lib/x86_64-linux-gnu/libc.so.6 so=so useshrplib=false libperl=libperl.a gnulibc_version='2.36' Dynamic Linking: dlsrc=dl_dlopen.xs dlext=so d_dlsymun=undef ccdlflags='-Wl,-E' cccdlflags='-fPIC' lddlflags='-shared -O2 -L/usr/local/lib -fstack-protector-strong' Characteristics of this binary (from libperl): Compile-time options: HAS_LONG_DOUBLE HAS_STRTOLD HAS_TIMES PERLIO_LAYERS PERL_COPY_ON_WRITE PERL_DONT_CREATE_GVSV PERL_HASH_FUNC_SIPHASH13 PERL_HASH_USE_SBOX32 PERL_MALLOC_WRAP PERL_OP_PARENT PERL_PRESERVE_IVUV PERL_USE_SAFE_PUTENV USE_64_BIT_ALL USE_64_BIT_INT USE_LARGE_FILES USE_LOCALE USE_LOCALE_COLLATE USE_LOCALE_CTYPE USE_LOCALE_NUMERIC USE_LOCALE_TIME USE_PERLIO USE_PERL_ATOF Built under linux Compiled at Aug 5 2024 00:46:42 %ENV: PERL_CPANM_OPT="--cascade-search --mirror-only --mirror /home/dj/Work/darkpan --mirror http://www.cpan.org" PERL_CPAN_MIRROR_TINY_BASE="/home/dj/Work/darkpan" PERL_DARKPAN="/home/dj/Work/darkpan" @INC: /home/dj/.plenv/versions/5.40/lib/perl5/site_perl/5.40.0/x86_64-linux /home/dj/.plenv/versions/5.40/lib/perl5/site_perl/5.40.0 /home/dj/.plenv/versions/5.40/lib/perl5/5.40.0/x86_64-linux /home/dj/.plenv/versions/5.40/lib/perl5/5.40.0