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#! /usr/bin/env perl -w
BEGIN {
  if ($ENV{PERL_CORE}){
    chdir('t') if -d 't';
    @INC = ('.', 'lib', '../lib');
  } else {
    unshift @INC, 't';
  }
  require Config;
  if ($ENV{PERL_CORE} and ($Config::Config{'extensions'} !~ /\bB\b/) ){
    print "1..0 # Skip -- Perl configured without B module\n";
    exit 0;
  }
  require 'test.pl';
}

use strict;
use Config;
use File::Spec;
use File::Path;

my $path = File::Spec->catdir( 'lib', 'B' );
unless (-d $path) {
  mkpath( $path ) or skip_all( 'Cannot create fake module path' );
}

my $file = File::Spec->catfile( $path, 'success.pm' );
local *OUT;
open(OUT, '>', $file) or skip_all( 'Cannot write fake backend module');
print OUT while <DATA>;
close *OUT;

plan tests => 9; # And someone's responsible.

# use() makes it difficult to avoid O::import()
require_ok( 'O' );

my @args = ('-Ilib', '-MO=success,foo,bar', $ENV{HARNESS_PERL_SWITCHES} || '', '-e', '1' );
my @lines = get_lines( @args );

is( $lines[0], 'Compiling!', 'Output should not be saved without -q switch' );
is( $lines[1], '(foo) <bar>', 'O.pm should call backend compile() method' );
is( $lines[2], '[]', 'Nothing should be in $O::BEGIN_output without -q' );
SKIP: {
  skip( 'stderr redirection to stdout does not work on Win32 cmd', 1)
    if $^O eq 'MSWin32';
  is( $lines[3], '-e syntax OK', 'O.pm should not munge perl output without -qq');
}

$args[1] = '-MO=-q,success,foo,bar';
@lines = get_lines( @args );
isnt( $lines[1], 'Compiling!', 'Output should not be printed with -q switch' );

SKIP: {
  skip( '-q redirection does not work without PerlIO', 2)
    unless $Config{useperlio};
  is( $lines[1], "[Compiling!", '... but should be in $O::BEGIN_output' );

  $args[1] = '-MO=-qq,success,foo,bar';
  @lines = get_lines( @args );
  is( scalar @lines, 3, '-qq should suppress even the syntax OK message' );
}

SKIP: {
  skip( 'Wrong O.pm die eval message with 5.6', 1) if $] < 5.007;
  skip( 'stderr redirection to stdout does not work on Win32 cmd', 1)
    if $^O eq 'MSWin32';

  $args[1] = '-MO=success,fail';
  @lines = get_lines( @args );
  like( $lines[1], qr/fail at .eval/,
        'O.pm should die if backend compile() does not return a subref' );
}

sub get_lines {
  split(/[\r\n]+/, runperl( args => [ @_ ], stderr => 1 ));
}

END {
  1 while unlink($file);
  rmdir($path); # not "1 while" since there might be more in there
}

__END__
package B::success;

$| = 1;
print "Compiling!\n";

sub compile {
  return 'fail' if ($_[0] eq 'fail');
  print "($_[0]) <$_[1]>\n";
  return sub { print "[$O::BEGIN_output]\n" };
}

1;