use strict;
use warnings FATAL => 'all';
use Test::More qw(no_plan);

BEGIN {

  package MyExporter;

  use base qw(Exporter);

  our @EXPORT_OK = qw(thing);

  sub thing { 'thing' }

  $INC{"MyExporter.pm"} = 1;

  package MultiExporter;

  use Import::Into;

  sub import {
    my $target = caller;
    warnings->import::into($target);
    MyExporter->import::into($target, 'thing');
    CheckFile->import::into(1);

  }

  $INC{"MultiExporter.pm"} = 1;
}

my @checkcaller;
my $checkversion;
BEGIN {

  package CheckFile;

  sub import {
    @checkcaller = caller;
  }
  sub VERSION {
    $checkversion = $_[1];
  }

  $INC{"CheckFile.pm"} = 1;
}

eval q{

  package TestPackage;

  no warnings FATAL => 'all';

#line 1 "import_into_inline.pl"
  use MultiExporter;

  sub test {
    thing . undef
  }
  1;
} or die $@;

my @w;

is(do {
  local $SIG{__WARN__} = sub { push @w, @_; };
  TestPackage::test();
}, 'thing', 'returned thing ok');

is(scalar @w, 1, 'Only one entry in @w');

like($w[0], qr/uninitialized/, 'Correct warning');

is $checkcaller[0], 'TestPackage', 'import by level has correct package';
is $checkcaller[1], 'import_into_inline.pl', 'import by level has correct file';
is $checkcaller[2], 1, 'import by level has correct line';

CheckFile->import::into({
  package  => 'ExplicitPackage',
  filename => 'explicit-file.pl',
  line     => 42,
  version  => 219,
});

is $checkcaller[0], 'ExplicitPackage',  'import with hash has correct package';
is $checkcaller[1], 'explicit-file.pl', 'import with hash has correct file';
is $checkcaller[2], 42,                 'import with hash has correct line';
is $checkversion, 219,                  'import with hash has correct version';

ok( !IPC::Open3->can("open3"), "IPC::Open3 is unloaded" );
IPC::Open3->import::into("TestPackage");
ok( TestPackage->can("open3"), "IPC::Open3 was use'd and import::into'd" );