[perl #132923] RFE: enhancement of corelist script

# New Ticket Created by  Linda Walsh 
# Please include the string:  [perl #132923]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=132923 >



This is a bug report for perl from perl-diddler@tlinx.org,
generated with the help of perlbug 1.40 running under perl 5.26.0.


-----------------------------------------------------------------
[Please describe your issue here]

I would like to propose an enhancement for the 'corelist'
command that comes with the CORE module 'Modules::CoreList'

Proposal is to add switch(es) '-t|--test' that would
act like '-v $] <MODNAME>' with the difference that
instead of telling you what version of the module is
in the given version of perl ($]=current), it returns
status via the script exit value: 0 if present, 1 if not.

This gives an easy way to test if a module is present in
CORE vs. need to be fetched from CPAN.

I threw together a sample patch against 5.26.0
for the 'corelist' program for my own use, and thought
it would be a good feature addition for the module in
CORE.

=====================
--- corelist.orig	2017-09-26 10:05:01.000000000 -0700
+++ corelist	2018-02-28 13:38:09.750160500 -0800
@@ -14,6 +14,7 @@
 =head1 SYNOPSIS
 
    corelist -v
+   corelist -t [ <ModuleName ]
    corelist [-a|-d] <ModuleName> | /<ModuleRegex>/ [<ModuleVersion>] ...
    corelist [-v <PerlVersion>] [ <ModuleName> | /<ModuleRegex>/ ] ...
    corelist [-r <PerlVersion>] ...
@@ -145,7 +146,8 @@
 
 GetOptions(
     \%Opts,
-    qw[ help|?! man! r|release:s v|version:s a! d diff|D feature|f u|upstream ]
+    qw[ help|?! man! r|release:s v|version:s a! d diff|D feature|f u|upstream 
+	t|test a!]
 );
 
 pod2usage(1) if $Opts{help};
@@ -175,6 +177,8 @@
     exit 0;
 }
 
+$Opts{v}=$] if exists($Opts{t}) ? 1 : 0;
+
 if(exists $Opts{v} ){
     if( !$Opts{v} ) {
	 print "\nModule::CoreList has info on the following perl versions:\n";
@@ -278,6 +282,8 @@
     pod2usage(0);
 }
 
+my $exit_status=0;
+
 while (@ARGV) {
	my ($mod, $ver);
	if ($ARGV[0] =~ /=/) {
@@ -288,7 +294,7 @@
	}
 
	if ($mod !~ m|^/(.*)/([imosx]*)$|) { # not a regex
-	    module_version($mod,$ver);
+	    ++$exit_status if module_version($mod,$ver);
	} else {
	    my $re;
	    eval { $re = $2 ? qr/(?$2)($1)/ : qr/$1/; }; # trap exceptions while building regex
@@ -310,7 +316,7 @@
	}
 }
 
-exit();
+exit($exit_status);
 
 sub module_version {
     my($mod,$ver) = @_;
@@ -319,8 +325,9 @@
	my $numeric_v = numify_version($Opts{v});
	my $version_hash = Module::CoreList->find_version($numeric_v);
	if ($version_hash) {
+	    return $version_hash->{$mod} ? 0 : 1 if $Opts{t};
	    print $mod, " ", $version_hash->{$mod} || 'undef', "\n";
-	    return;
+	    return 0;
	}
	else { die "Shouldn't happen" }
     }
=====================

The above is the simple case of checking for the module
in the running vesrion of perl

Thanks,
Linda Walsh

[Please do not change anything below this line]
-----------------------------------------------------------------
---
Flags:
    category=core
    severity=wishlist
---
Site configuration information for perl 5.26.0:

Configured by law at Sat Oct  7 15:42:15 PDT 2017.

Summary of my perl5 (revision 5 version 26 subversion 0) configuration:
   
  Platform:
    osname=linux
    osvers=4.13.5-isht-van
    archname=x86_64-linux-thread-multi-ld
    uname='linux ishtar 4.13.5-isht-van #2 smp preempt thu oct 5 15:26:06 pdt 2017 x86_64 gnulinux '
    config_args=''
    hint=recommended
    useposix=true
    d_sigaction=define
    useithreads=define
    usemultiplicity=define
    use64bitint=define
    use64bitall=define
    uselongdouble=define
    usemymalloc=n
    default_inc_excludes_dot=undef
    bincompat5005=undef
  Compiler:
    cc='gcc'
    ccflags ='-D_REENTRANT -D_GNU_SOURCE -fwrapv -fno-strict-aliasing -pipe -fstack-protector-explicit -I/home/perl/perl-5.26.0/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64'
    optimize='-O2'
    cppflags='-D_REENTRANT -D_GNU_SOURCE -fwrapv -fno-strict-aliasing -pipe -fstack-protector-explicit -I/home/perl/perl-5.26.0/include'
    ccversion=''
    gccversion='7.1.0'
    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='long double'
    nvsize=16
    Off_t='off_t'
    lseeksize=8
    alignbytes=16
    prototype=define
  Linker and Libraries:
    ld='gcc'
    ldflags ='-fstack-protector-explicit -I/home/perl/perl-5.26.0/include'
    libpth=/usr/local/lib //lib /usr/lib64/gcc/x86_64-pc-linux-gnu/7/include-fixed /usr/lib /lib/../lib64 /usr/lib/../lib64 /lib /lib64 /usr/lib64
    libs=-lpthread -lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lc -lgdbm_compat
    perllibs=-lpthread -lnsl -ldl -lm -lcrypt -lutil -lc
    libc=libc-2.19.so
    so=so
    useshrplib=true
    libperl=libperl-5.26.0.so
    gnulibc_version='2.19'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs
    dlext=so
    d_dlsymun=undef
    ccdlflags='-Wl,-E -Wl,-rpath,/home/perl/perl-5.26.0/usr/lib/5.26.0/x86_64-linux-thread-multi-ld/CORE'
    cccdlflags='-fPIC'
    lddlflags='-shared -O2'


---
@INC for perl 5.26.0:
    /home/law/bin/lib
    /home/perl/perl-5.26.0/usr/lib/site_perl/5.26.0/x86_64-linux-thread-multi-ld
    /home/perl/perl-5.26.0/usr/lib/site_perl/5.26.0
    /home/perl/perl-5.26.0/usr/lib/5.26.0/x86_64-linux-thread-multi-ld
    /home/perl/perl-5.26.0/usr/lib/5.26.0

---
Environment for perl 5.26.0:
    HOME=/home/law
    LANG (unset)
    LANGUAGE (unset)
    LC_COLLATE=C
    LC_CTYPE=en_US.UTF-8
    LC_MESSAGES=C
    LC_MONETARY=C
    LC_NUMERIC=C
    LC_TIME=C
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/home/perl/perl-5.26.0:.:/sbin:/home/law/bin/lib:/home/law/bin:/usr/local/bin:/usr/bin:/bin:/opt/kde3/bin:/usr/sbin:/etc/local/func_lib:/home/law/lib
    PERL5OPT=-Mutf8 -CSA -I/home/law/bin/lib
    PERL_BADLANG (unset)
    SHELL=/bin/bash

• [perl #132923] RFE: enhancement of corelist script by Linda Walsh