+#!perl -T
+
+use strict;
+use warnings;
+
+BEGIN { $ENV{PERL_TEST_LEANER_USES_TEST_MORE} = 1 }
+
+use Test::Leaner;
+
+BEGIN {
+ my $loaded;
+ if ($INC{'Test/More.pm'}) {
+ $loaded = 1;
+ } else {
+ $loaded = 0;
+ require Test::More;
+ Test::More->import;
+ }
+ Test::More::plan(tests => 1 + 4 * 15 + 3 * 3 + 2 * 8);
+ Test::More::is($loaded, 1, 'Test::More has been loaded');
+}
+
+sub get_subroutine {
+ my ($stash, $name) = @_;
+
+ my $glob = $stash->{$name};
+ return undef unless $glob;
+
+ return *$glob{CODE};
+}
+
+my $leaner_stash = \%Test::Leaner::;
+my $more_stash = \%Test::More::;
+my $this_stash = \%main::;
+
+my @exported = qw<
+ plan
+ skip
+ done_testing
+ pass
+ fail
+ ok
+ is
+ isnt
+ like
+ unlike
+ cmp_ok
+ is_deeply
+ diag
+ note
+ BAIL_OUT
+>;
+
+for (@exported) {
+ my $more_variant = get_subroutine($more_stash, $_);
+
+ my $leaner_variant = get_subroutine($leaner_stash, $_);
+ Test::More::ok(defined $leaner_variant,
+ "Test::Leaner variant of $_ is defined");
+ my $imported_variant = get_subroutine($this_stash, $_);
+ Test::More::ok(defined $imported_variant, "imported variant of $_ is defined");
+
+ SKIP: {
+ Test::More::skip('Need leaner and imported variants to be defined' => 2)
+ unless defined $leaner_variant
+ and defined $imported_variant;
+
+ if (defined $more_variant) {
+ Test::More::is($leaner_variant, $more_variant,
+ "Test::Leaner variant of $_ is Test::More variant");
+ Test::More::is($imported_variant, $more_variant,
+ "imported variant of $_ is Test::More variant");
+ } else {
+ Test::More::is($imported_variant, $leaner_variant,
+ "imported variant of $_ is Test::Leaner variant");
+ {
+ local $@;
+ eval { $leaner_variant->() };
+ Test::More::like($@, qr/^\Q$_\E is not implemented.*at \Q$0\E line \d+/,
+ "Test::Leaner of $_ variant croaks");
+ }
+ }
+ }
+}
+
+my @only_in_test_leaner = qw<
+ tap_stream
+ diag_stream
+ THREADSAFE
+>;
+
+for (@only_in_test_leaner) {
+ Test::More::ok(exists $leaner_stash->{$_},
+ "$_ still exists in Test::Leaner");
+ Test::More::ok(!exists $more_stash->{$_},
+ "$_ was not imported into Test::More");
+ Test::More::ok(!exists $this_stash->{$_},
+ "$_ was not imported into main");
+}
+
+my @only_in_test_more = qw<
+ use_ok
+ require_ok
+ can_ok
+ isa_ok
+ new_ok
+ subtest
+ explain
+ todo_skip
+>;
+
+for (@only_in_test_more) {
+ my $more_variant = get_subroutine($more_stash, $_);
+
+ SKIP: {
+ Test::More::skip("$_ is not implemented in this version of Test::More" => 2)
+ unless defined $more_variant;
+
+ Test::More::ok(!exists $leaner_stash->{$_},
+ "$_ was not imported into Test::Leaner");
+ Test::More::ok(!exists $this_stash->{$_},
+ "$_ was not imported into main");
+ }
+}