diff --git a/t/mojo/delay.t b/t/mojo/delay.t
index 30e53d4ed0..15b83b99b9 100644
--- a/t/mojo/delay.t
+++ b/t/mojo/delay.t
@@ -6,197 +6,210 @@ use Test::More;
 use Mojo::IOLoop;
 use Mojo::IOLoop::Delay;
 
-# Promise (all)
-my $delay  = Mojo::IOLoop::Delay->new->then(sub {@_});
-my $delay2 = Mojo::IOLoop::Delay->new->then(sub {@_});
-my $delay3 = Mojo::IOLoop::Delay->new->then(sub {@_});
-my @results;
-Mojo::Promise->all($delay, $delay2, $delay3)->then(sub { @results = @_ });
-$delay2->resolve('second');
-$delay3->resolve('third');
-$delay->resolve('first');
-Mojo::IOLoop->one_tick;
-is_deeply \@results, [['first'], ['second'], ['third']], 'promises resolved';
-
-# Basic functionality
-$delay   = Mojo::IOLoop::Delay->new;
-@results = ();
-for my $i (1, 1) {
-  my $end = $delay->begin;
-  Mojo::IOLoop->next_tick(sub { push @results, $i; $end->() });
-}
-my $end  = $delay->begin;
-my $end2 = $delay->begin;
-$end->();
-$end2->();
-$delay->wait;
-is_deeply \@results, [1, 1], 'right results';
-
-# Argument splicing
-$delay = Mojo::IOLoop::Delay->new;
-Mojo::IOLoop->next_tick($delay->begin);
-$delay->begin(1)->(1, 2, 3);
-$delay->begin(1, 1)->(4, 5, 6);
-$delay->begin(0, 1)->(7, 8);
-$delay->begin(2)->(9, 10, 11);
-$delay->begin(0, 0)->(12, 13);
-$delay->begin(0, 2)->(14, 15, 16);
-$delay->begin(2, 5)->(17, 18, 19, 20);
-my @numbers;
-$delay->steps(sub { (undef, @numbers) = @_ })->wait;
-is_deeply \@numbers, [2, 3, 5, 7, 11, 14, 15, 19, 20], 'right values';
-
-# Steps
-my $result;
-$delay = Mojo::IOLoop::Delay->new;
-$delay->steps(
-  sub {
-    my $delay = shift;
-    my $end   = $delay->begin;
-    $delay->begin->(3, 2, 1);
-    Mojo::IOLoop->next_tick(sub { $end->(1, 2, 3)->pass(5) });
-  },
-  sub {
-    my ($delay, @numbers) = @_;
+subtest 'Promise (all)' => sub {
+  my $delay  = Mojo::IOLoop::Delay->new->then(sub {@_});
+  my $delay2 = Mojo::IOLoop::Delay->new->then(sub {@_});
+  my $delay3 = Mojo::IOLoop::Delay->new->then(sub {@_});
+  my @results;
+  Mojo::Promise->all($delay, $delay2, $delay3)->then(sub { @results = @_ });
+  $delay2->resolve('second');
+  $delay3->resolve('third');
+  $delay->resolve('first');
+  Mojo::IOLoop->one_tick;
+  is_deeply \@results, [['first'], ['second'], ['third']], 'promises resolved';
+};
+
+subtest 'Basic functionality' => sub {
+  my $delay = Mojo::IOLoop::Delay->new;
+  my @results;
+  for my $i (1, 1) {
     my $end = $delay->begin;
-    Mojo::IOLoop->next_tick(sub { $end->(undef, @numbers, 4) });
-  },
-  sub {
-    my ($delay, @numbers) = @_;
-    $result = \@numbers;
-  }
-)->wait;
-is_deeply $result, [2, 3, 2, 1, 4, 5], 'right results';
-
-# One step
-$result = undef;
-$delay  = Mojo::IOLoop::Delay->new;
-$delay->steps(sub { ++$result });
-$delay->begin->();
-is $result, undef, 'no result';
-Mojo::IOLoop->next_tick($delay->begin);
-is $result, undef, 'no result';
-$end = $delay->begin;
-Mojo::IOLoop->next_tick(sub { $end->() });
-is $result, undef, 'no result';
-$delay->wait;
-is $result, 1, 'right result';
-
-# One step (reverse)
-$result = undef;
-$delay  = Mojo::IOLoop::Delay->new;
-$end    = $delay->begin(0);
-Mojo::IOLoop->next_tick(sub { $end->(23) });
-$delay->steps(sub { $result = pop });
-is $result, undef, 'no result';
-$delay->wait;
-is $result, 23, 'right result';
-
-# End chain after first step
-$result = undef;
-$delay  = Mojo::IOLoop::Delay->new;
-$delay->steps(sub { $result = 'success' }, sub { $result = 'fail' });
-$delay->wait;
-is $result, 'success', 'right result';
-
-# End chain after third step
-$result = undef;
-$delay  = Mojo::IOLoop::Delay->new;
-$delay->steps(
-  sub { Mojo::IOLoop->next_tick(shift->begin) },
-  sub {
-    $result = 'fail';
-    shift->pass;
-  },
-  sub { $result = 'success' },
-  sub { $result = 'fail' }
-)->wait;
-is $result, 'success', 'right result';
-
-# End chain after second step
-@results = ();
-$delay   = Mojo::IOLoop::Delay->new;
-$delay->then(sub { push @results, [@_] });
-$delay->steps(sub { shift->pass(23) }, sub { shift; push @results, [@_] }, sub { push @results, 'fail' })->wait;
-is_deeply \@results, [[23], [23]], 'right results';
-
-# Nested delays
-$result = undef;
-$delay  = Mojo::IOLoop->delay(
-  sub {
-    my $first  = shift;
-    my $second = Mojo::IOLoop->delay($first->begin);
-    Mojo::IOLoop->next_tick($second->begin);
-    Mojo::IOLoop->next_tick($first->begin);
-    my $end = $second->begin(0);
-    Mojo::IOLoop->next_tick(sub { $end->(1, 2, 3) });
-  },
-  sub {
-    my ($first, @numbers) = @_;
-    $result = \@numbers;
-    my $end = $first->begin;
-    $first->begin->(3, 2, 1);
-    my $end2 = $first->begin(0);
-    my $end3 = $first->begin(0);
-    $end2->(4);
-    $end3->(5, 6);
-    $first->pass(23)->pass(24);
-    $end->(1, 2, 3);
-  },
-  sub {
-    my ($first, @numbers) = @_;
-    push @$result, @numbers;
+    Mojo::IOLoop->next_tick(sub { push @results, $i; $end->() });
   }
-)->wait;
-is_deeply $result, [1, 2, 3, 2, 3, 2, 1, 4, 5, 6, 23, 24], 'right results';
-
-# Exception in first step
-my $failed;
-$result = undef;
-$delay  = Mojo::IOLoop::Delay->new;
-$delay->steps(sub { die 'First step!' }, sub { $result = 'failed' })->catch(sub { $failed = shift })->wait;
-like $failed, qr/^First step!/, 'right error';
-ok !$result, 'no result';
-
-# Exception in last step
-$failed = undef;
-$delay  = Mojo::IOLoop::Delay->new;
-$delay->steps(sub { Mojo::IOLoop->next_tick(shift->begin) }, sub { die 'Last step!' })->catch(sub { $failed = pop })
-  ->wait;
-like $failed, qr/^Last step!/, 'right error';
-
-# Exception in second step
-($failed, $result) = ();
-$delay = Mojo::IOLoop::Delay->new;
-$delay->steps(
-  sub {
-    my $end = shift->begin;
-    Mojo::IOLoop->next_tick(sub {
-      $result = 'pass';
-      $end->();
-    });
-  },
-  sub { die 'Second step!' },
-  sub { $result = 'failed' }
-);
-$delay->catch(sub { $failed = shift })->wait;
-like $failed, qr/^Second step!/, 'right error';
-is $result,   'pass',            'right result';
-
-# Exception in second step (with active event)
-($failed, $result) = ();
-$delay = Mojo::IOLoop::Delay->new;
-$delay->steps(
-  sub { Mojo::IOLoop->next_tick(shift->begin) },
-  sub {
-    Mojo::IOLoop->next_tick(sub { Mojo::IOLoop->stop });
-    Mojo::IOLoop->next_tick(shift->begin);
-    die 'Second step!';
-  },
-  sub { $result = 'failed' }
-)->catch(sub { $failed = shift });
-Mojo::IOLoop->start;
-like $failed, qr/^Second step!/, 'right error';
-ok !$result, 'no result';
+  my $end  = $delay->begin;
+  my $end2 = $delay->begin;
+  $end->();
+  $end2->();
+  $delay->wait;
+  is_deeply \@results, [1, 1], 'right results';
+};
+
+subtest 'Argument splicing' => sub {
+  my $delay = Mojo::IOLoop::Delay->new;
+  Mojo::IOLoop->next_tick($delay->begin);
+  $delay->begin(1)->(1, 2, 3);
+  $delay->begin(1, 1)->(4, 5, 6);
+  $delay->begin(0, 1)->(7, 8);
+  $delay->begin(2)->(9, 10, 11);
+  $delay->begin(0, 0)->(12, 13);
+  $delay->begin(0, 2)->(14, 15, 16);
+  $delay->begin(2, 5)->(17, 18, 19, 20);
+  my @numbers;
+  $delay->steps(sub { (undef, @numbers) = @_ })->wait;
+  is_deeply \@numbers, [2, 3, 5, 7, 11, 14, 15, 19, 20], 'right values';
+};
+
+subtest 'Steps' => sub {
+  my $result;
+  my $delay = Mojo::IOLoop::Delay->new;
+  $delay->steps(
+    sub {
+      my $delay = shift;
+      my $end   = $delay->begin;
+      $delay->begin->(3, 2, 1);
+      Mojo::IOLoop->next_tick(sub { $end->(1, 2, 3)->pass(5) });
+    },
+    sub {
+      my ($delay, @numbers) = @_;
+      my $end = $delay->begin;
+      Mojo::IOLoop->next_tick(sub { $end->(undef, @numbers, 4) });
+    },
+    sub {
+      my ($delay, @numbers) = @_;
+      $result = \@numbers;
+    }
+  )->wait;
+  is_deeply $result, [2, 3, 2, 1, 4, 5], 'right results';
+};
+
+subtest 'One step' => sub {
+  my $result;
+  my $delay = Mojo::IOLoop::Delay->new;
+  $delay->steps(sub { ++$result });
+  $delay->begin->();
+  is $result, undef, 'no result';
+  Mojo::IOLoop->next_tick($delay->begin);
+  is $result, undef, 'no result';
+  my $end = $delay->begin;
+  Mojo::IOLoop->next_tick(sub { $end->() });
+  is $result, undef, 'no result';
+  $delay->wait;
+  is $result, 1, 'right result';
+};
+
+subtest 'One step (reverse)' => sub {
+  my $result;
+  my $delay = Mojo::IOLoop::Delay->new;
+  my $end   = $delay->begin(0);
+  Mojo::IOLoop->next_tick(sub { $end->(23) });
+  $delay->steps(sub { $result = pop });
+  is $result, undef, 'no result';
+  $delay->wait;
+  is $result, 23, 'right result';
+};
+
+subtest 'End chain after first step' => sub {
+  my $result;
+  my $delay = Mojo::IOLoop::Delay->new;
+  $delay->steps(sub { $result = 'success' }, sub { $result = 'fail' });
+  $delay->wait;
+  is $result, 'success', 'right result';
+};
+
+subtest 'End chain after third step' => sub {
+  my $result;
+  my $delay = Mojo::IOLoop::Delay->new;
+  $delay->steps(
+    sub { Mojo::IOLoop->next_tick(shift->begin) },
+    sub {
+      $result = 'fail';
+      shift->pass;
+    },
+    sub { $result = 'success' },
+    sub { $result = 'fail' }
+  )->wait;
+  is $result, 'success', 'right result';
+};
+
+subtest 'End chain after second step' => sub {
+  my @results;
+  my $delay = Mojo::IOLoop::Delay->new;
+  $delay->then(sub { push @results, [@_] });
+  $delay->steps(sub { shift->pass(23) }, sub { shift; push @results, [@_] }, sub { push @results, 'fail' })->wait;
+  is_deeply \@results, [[23], [23]], 'right results';
+};
+
+subtest 'Nested delays' => sub {
+  my $result;
+  my $delay = Mojo::IOLoop->delay(
+    sub {
+      my $first  = shift;
+      my $second = Mojo::IOLoop->delay($first->begin);
+      Mojo::IOLoop->next_tick($second->begin);
+      Mojo::IOLoop->next_tick($first->begin);
+      my $end = $second->begin(0);
+      Mojo::IOLoop->next_tick(sub { $end->(1, 2, 3) });
+    },
+    sub {
+      my ($first, @numbers) = @_;
+      $result = \@numbers;
+      my $end = $first->begin;
+      $first->begin->(3, 2, 1);
+      my $end2 = $first->begin(0);
+      my $end3 = $first->begin(0);
+      $end2->(4);
+      $end3->(5, 6);
+      $first->pass(23)->pass(24);
+      $end->(1, 2, 3);
+    },
+    sub {
+      my ($first, @numbers) = @_;
+      push @$result, @numbers;
+    }
+  )->wait;
+  is_deeply $result, [1, 2, 3, 2, 3, 2, 1, 4, 5, 6, 23, 24], 'right results';
+};
+
+subtest 'Exception in first step' => sub {
+  my ($failed, $result);
+  my $delay = Mojo::IOLoop::Delay->new;
+  $delay->steps(sub { die 'First step!' }, sub { $result = 'failed' })->catch(sub { $failed = shift })->wait;
+  like $failed, qr/^First step!/, 'right error';
+  ok !$result, 'no result';
+};
+
+subtest 'Exception in last step' => sub {
+  my $failed;
+  my $delay = Mojo::IOLoop::Delay->new;
+  $delay->steps(sub { Mojo::IOLoop->next_tick(shift->begin) }, sub { die 'Last step!' })->catch(sub { $failed = pop })
+    ->wait;
+  like $failed, qr/^Last step!/, 'right error';
+};
+
+subtest 'Exception in second step' => sub {
+  my ($failed, $result);
+  my $delay = Mojo::IOLoop::Delay->new;
+  $delay->steps(
+    sub {
+      my $end = shift->begin;
+      Mojo::IOLoop->next_tick(sub {
+        $result = 'pass';
+        $end->();
+      });
+    },
+    sub { die 'Second step!' },
+    sub { $result = 'failed' }
+  );
+  $delay->catch(sub { $failed = shift })->wait;
+  like $failed, qr/^Second step!/, 'right error';
+  is $result,   'pass',            'right result';
+};
+
+subtest 'Exception in second step (with active event)' => sub {
+  my ($failed, $result);
+  my $delay = Mojo::IOLoop::Delay->new;
+  $delay->steps(
+    sub { Mojo::IOLoop->next_tick(shift->begin) },
+    sub {
+      Mojo::IOLoop->next_tick(sub { Mojo::IOLoop->stop });
+      Mojo::IOLoop->next_tick(shift->begin);
+      die 'Second step!';
+    },
+    sub { $result = 'failed' }
+  )->catch(sub { $failed = shift });
+  Mojo::IOLoop->start;
+  like $failed, qr/^Second step!/, 'right error';
+  ok !$result, 'no result';
+};
 
 done_testing();