t/op/coresubs.t

#!./perl

# This script tests the inlining and prototype of CORE:: subs.  Any generic
# tests that are not specific to &foo-style calls should go in this
# file, too.

BEGIN {
    chdir 't' if -d 't';
    require "./test.pl";
    set_up_inc(qw(. ../lib));
    skip_all_without_dynamic_extension('B');
    $^P |= 0x100;
}

use B;

my %unsupported = map +($_=>1), qw (
 __DATA__ __END__ ADJUST AUTOLOAD BEGIN UNITCHECK CORE DESTROY END INIT CHECK
  and catch class cmp default defer do dump else elsif eq eval field
  finally for foreach format ge given goto grep gt if isa last le local
  lt m map method my ne next no or our package print printf q qq qr qw qx
  redo require return s say sort state sub tr try unless until use
  when while x xor y
);
my %args_for = (
  dbmopen  => '%1,$2,$3',
 (dbmclose => '%1',
  keys     =>
  values   =>
  each     =>)[0,1,2,1,3,1,4,1],
  delete   => '$1[2]',
  exists   => '$1[2]',
 (push     => '@1',
  pop      =>
  shift    =>
  unshift  =>
  splice   =>)[0,1,2,1,3,1,4,1,5,1],
);
my %desc = (
  #pos => 'match position',
);

use File::Spec::Functions;
my $keywords_file = catfile(updir,'regen','keywords.pl');
open my $kh, $keywords_file
   or die "$0 cannot open $keywords_file: $!";
while(<$kh>) {
  if (m?__END__?..${\0} and /^[+-]/) {
    chomp(my $word = $');
    if($unsupported{$word}) {
      $tests ++;
      ok !defined &{"CORE::$word"}, "no CORE::$word";
    }
    else {
      $tests += 2;

      ok defined &{"CORE::$word"}, "defined &{'CORE::$word'}";

      my $proto = prototype "CORE::$word";
      *{"my$word"} = \&{"CORE::$word"};
      is prototype \&{"my$word"}, $proto, "prototype of &CORE::$word";

      CORE::state $protochar = qr/([^\\]|\\(?:[^[]|\[[^]]+\]))/;
      my $numargs =
            $word eq 'delete' || $word eq 'exists' ? 1 :
            (() = $proto =~ s/;.*//r =~ /\G$protochar/g);

      inlinable_ok($word, $args_for{$word} || join ",", map "\$$_", 1..$numargs);

      # High-precedence tests
      my $hpcode;
      if (!$proto && defined $proto) { # nullary
         $hpcode = "sub { () = my$word + 1 }";
      }
      elsif ($proto =~ /^;?$protochar\z/) { # unary
         $hpcode = "sub { () = my$word "
                           . ($args_for{$word}||'$a') . ' > $b'
                       .'}';
      }
      if ($hpcode) {
         $tests ++;
         # __FILE__ won’t fold with warnings on, and then we get
         # ‘(eval 21)’ vs ‘(eval 22)’.
         no warnings 'numeric';
         $core = op_list(eval $hpcode =~ s/my/CORE::/r or die);
         $my   = op_list(eval $hpcode or die);
         is $my, $core, "precedence of CORE::$word without parens";
      }

      next if ($proto =~ /\@/);
      # These ops currently accept any number of args, despite their
      # prototypes, if they have any:
      next if $word =~ /^(?:chom?p|exec|keys|each|not
                           |(?:prototyp|read(?:lin|pip))e
                           |reset|system|values|l?stat)|evalbytes/x;

      $tests ++;
      $code =
         "sub { () = (my$word("
             . (
                $args_for{$word}
                 ? $args_for{$word}.',$7'
                 : join ",", map "\$$_", 1..$numargs+5+(
                      $proto =~ /;/
                       ? () = $' =~ /\G$protochar/g
                       : 0
                   )
               )
       . "))}";
      eval $code;
      my $desc = $desc{$word} || $word;
      like $@, qr/^Too many arguments for $desc/,
          "inlined CORE::$word with too many args"
        or warn $code;

    }
  }
}

sub B::OP::pushname { push @op_names, shift->name }

sub op_list {
    local @op_names;
    B::walkoptree(B::svref_2object($_[0])->ROOT, 'pushname');
    return "@op_names";
}

sub inlinable_ok {
  my ($word, $args, $desc_suffix) = @_;
  $tests += 2;

  $desc_suffix //= '';

  for ([with => "($args)"], [without => " $args"]) {
    my ($preposition, $full_args) = @$_;
    my $core_code =
       "#line 1 This-line-makes-__FILE__-easier-to-test.
        sub { () = (CORE::$word$full_args) }";
    my $my_code = $core_code =~ s/CORE::$word/my$word/r;
    my $core = op_list(eval $core_code or die);
    my $my   = op_list(eval   $my_code or die);
    is $my, $core, "inlinability of CORE::$word $preposition parens $desc_suffix";
  }
}

$tests++;
# This subroutine is outside the warnings scope:
sub foo { goto &CORE::abs }
use warnings;
$SIG{__WARN__} = sub { like shift, qr\^Use of uninitialized\ };
foo(undef);

$tests+=2;
is runperl(prog => 'print CORE->lc, qq-\n-'), "core\n",
 'methods calls autovivify coresubs';
is runperl(prog => '@ISA=CORE; print main->uc, qq-\n-'), "MAIN\n",
 'inherted method calls autovivify coresubs';

{ # RT #117607
  $tests++;
  like runperl(prog => '$foo/; \&CORE::lc', stderr => 1),
    qr/^syntax error/, "RT #117607: \\&CORE::foo doesn't crash in error context";
}

$tests++;
ok eval { *CORE::exit = \42 },
  '[rt.cpan.org #74289] *CORE::foo is not accidentally made read-only';

inlinable_ok($_, '$_{k}', 'on hash')
    for qw<delete exists>;

@UNIVERSAL::ISA = CORE;
is "just another "->ucfirst . "perl hacker,\n"->ucfirst,
   "Just another Perl hacker,\n", 'coresubs do not return TARG';
++$tests;

done_testing $tests;

CORE::__END__