diff --git a/lib/Rethinkdb/Query.pm b/lib/Rethinkdb/Query.pm
index b347675..6316a54 100644
--- a/lib/Rethinkdb/Query.pm
+++ b/lib/Rethinkdb/Query.pm
@@ -414,17 +414,21 @@ sub sample {
 sub group {
   my $self = shift;
   my $args = [@_];
+  my $optargs = {};
 
-  my $reductor;
-  if ( ref $args->[ $#{$args} ] ) {
-    $reductor = pop @{$args};
-    $args = [ $args, $reductor ];
+  if ( ref $args->[ $#{$args} ] eq 'HASH' ) {
+    $optargs = pop @{$args};
+  }
+
+  if( ref $args->[0] && ref $args->[0] ne 'CODE' ) {
+    $args = Rethinkdb::Util->_wrap_func($args->[0]);
   }
 
   my $q = Rethinkdb::Query->new(
     _parent => $self,
     _type   => $self->_termType->group,
-    args    => $args
+    args    => $args,
+    optargs => $optargs
   );
 
   return $q;
@@ -469,7 +473,7 @@ sub count {
 
 sub sum {
   my $self = shift;
-  my $args = {@_};
+  my $args = [@_];
 
   my $q = Rethinkdb::Query->new(
     _parent => $self,
@@ -495,7 +499,7 @@ sub avg {
 
 sub min {
   my $self = shift;
-  my $args = {@_};
+  my $args = [@_];
 
   my $q = Rethinkdb::Query->new(
     _parent => $self,
@@ -508,7 +512,7 @@ sub min {
 
 sub max {
   my $self = shift;
-  my $args = {@_};
+  my $args = [@_];
 
   my $q = Rethinkdb::Query->new(
     _parent => $self,
diff --git a/t/aggregation.t b/t/aggregation.t
index 593b34a..1b5da27 100644
--- a/t/aggregation.t
+++ b/t/aggregation.t
@@ -161,6 +161,49 @@ r->table('dc')->insert(
   ]
 )->run;
 
+# group
+$res = r->table('marvel')->group('age')->avg('strength')->run;
+
+is $res->type, 1, 'Correct response type';
+is_deeply $res->response,
+  {
+  '1035' => '2035',
+  '35'   => '543.166666666667',
+  '135'  => '1035',
+  '20'   => '200',
+  },
+  'Correct response';
+
+# group by more than one field (we have to use `group_format=>'raw'`)
+$res = r->table('marvel')->group( 'age', 'active' )
+  ->run( { group_format => 'raw' } );
+
+is_deeply $res->response->{data}->[0][0], [ 20, 0 ];
+is $res->response->{data}->[0][1][0]->{superhero}, 'Spider-Man';
+
+# group using a function
+$res = r->table('marvel')->group(
+  sub {
+    my $row = shift;
+    return $row->pluck( 'age', 'active' );
+  }
+)->run( { group_format => 'raw' } );
+
+is_deeply $res->response->{data}->[0][0], { age => 20, active => 0 };
+is $res->response->{data}->[0][1][0]->{superhero}, 'Spider-Man';
+
+# group `multi=true`
+# r.table('games2').group(r.row['matches'].keys(), multi=True).run()
+$res = r->table('marvel')
+  ->group( r->row->bracket('dc_buddies'), { multi => r->true } )->run;
+
+is $#{ $res->response->{Batman} }, 3, 'Correct `multi=true` response';
+
+# ungroup
+$res = r->table('marvel')->group('age')->avg('strength')->ungroup->run;
+
+is_deeply [ sort keys %{ $res->response->[0] } ], [ 'group', 'reduction' ];
+
 # reduce
 $res = r->table('marvel')->map( r->row->bracket('age') )->reduce(
   sub ($$) {
@@ -199,6 +242,84 @@ $res = r->table('marvel')->count(
 is $res->type,     1,   'Correct response type';
 is $res->response, '4', 'Correct number of documents';
 
+# sum
+$res = r->expr( [ 3, 5, 7 ] )->sum->run($conn);
+
+is $res->response, 15, 'Correct response';
+
+# sum - document attributes
+$res = r->table('marvel')->sum('age')->run;
+
+is $res->response, 1400, 'Correct response';
+
+# sum - documents based on function
+$res = r->table('marvel')->sum(
+  sub {
+    my $row = shift;
+    return $row->bracket('strength')->mul( $row->bracket('active') );
+  }
+)->run;
+
+is $res->response, 6132, 'Correct response';
+
+# avg
+$res = r->expr( [ 3, 5, 7 ] )->avg->run($conn);
+
+is $res->response, 5, 'Correct response';
+
+# avg - document attributes
+$res = r->table('marvel')->avg('age')->run;
+
+is substr( $res->response, 0, 7 ), '155.555', 'Correct response';
+
+# avg - documents based on function
+$res = r->table('marvel')->avg(
+  sub {
+    my $row = shift;
+    return $row->bracket('strength')->mul( $row->bracket('active') );
+  }
+)->run;
+
+is substr( $res->response, 0, 7 ), '681.333', 'Correct response';
+
+# min
+$res = r->expr( [ 3, 5, 7 ] )->min->run($conn);
+
+is $res->response, 3, 'Correct response';
+
+# min - document attributes
+$res = r->table('marvel')->min('age')->run;
+is $res->response->{age}, 20, 'Correct response';
+
+# min - documents based on function
+$res = r->table('marvel')->min(
+  sub {
+    my $row = shift;
+    return $row->bracket('strength')->mul( $row->bracket('active') );
+  }
+)->run;
+
+is $res->response->{age}, 20, 'Correct response';
+
+# max
+$res = r->expr( [ 3, 5, 7 ] )->max->run($conn);
+
+is $res->response, 7, 'Correct response';
+
+# max - document attributes
+$res = r->table('marvel')->max('age')->run;
+is $res->response->{age}, 1035, 'Correct response';
+
+# max - documents based on function
+$res = r->table('marvel')->max(
+  sub {
+    my $row = shift;
+    return $row->bracket('strength')->mul( $row->bracket('active') );
+  }
+)->run;
+
+is $res->response->{age}, 1035, 'Correct response';
+
 # distinct (on table)
 $res = r->table('marvel')->distinct->run;
 
@@ -211,19 +332,6 @@ $res = r->expr( [ 1, 1, 1, 1, 1, 2, 3 ] )->distinct->run($conn);
 is $res->type, 1, 'Correct response type';
 is scalar @{ $res->response }, 3, 'Correct number of documents';
 
-# group_by
-$res = r->table('marvel')->group('age')->avg('strength')->run;
-
-is $res->type, 1, 'Correct response type';
-is_deeply $res->response,
-  {
-  '1035' => '2035',
-  '35'   => '543.166666666667',
-  '135'  => '1035',
-  '20'   => '200',
-  },
-  'Correct response';
-
 # contains
 $res = r->table('marvel')->get('Iron Man')->bracket('dc_buddies')
   ->contains('Superman')->run;
@@ -231,6 +339,17 @@ $res = r->table('marvel')->get('Iron Man')->bracket('dc_buddies')
 is $res->type, 1, 'Correct response type';
 is $res->response, r->true, 'Correct response value';
 
+$res = r->table('marvel')->filter(
+  sub {
+    my $hero = shift;
+    return r->expr( [ 'Smash', 'Size' ] )
+      ->contains( $hero->bracket('superpower') );
+  }
+)->bracket('superhero')->run;
+
+is_deeply sort $res->response, [ 'Ant-Man', 'Hulk' ],
+  'Correct filter & contains response';
+
 # clean up
 r->db('test')->drop->run;
 
diff --git a/t/control.t b/t/control.t
index f999306..26ab809 100644
--- a/t/control.t
+++ b/t/control.t
@@ -22,6 +22,7 @@ r->table('marvel')->insert(
       battles         => 3,
       villainDefeated => 'Mandarin',
       outfits         => 12,
+      gadget          => 'Shoulder-mounted rocket launcher'
     },
     {
       user_id         => 8,
@@ -40,7 +41,8 @@ r->table('marvel')->insert(
       age             => 20,
       victories       => 24,
       battles         => 3,
-      villainDefeated => 'Green Goblin'
+      villainDefeated => 'Green Goblin',
+      gadget          => 'Web-slinger'
     }
   ]
 )->run;
@@ -126,6 +128,13 @@ is $res->type, 2, 'Correct response type';
 is_deeply [ sort { $a <=> $b } @{ $res->response } ], [ '0', '2', '13' ],
   'Correct response';
 
+$res = r->table('marvel')->map(r->row->bracket('gadget')->default)->run;
+
+is $res->type, 2, 'Correct response type';
+is_deeply [ sort @{ $res->response } ], [ undef, 'Shoulder-mounted rocket launcher', 'Web-slinger' ],
+  'Correct response';
+
+
 # expr
 $res = r->expr( { 'a' => 'b' } )->merge( { 'b' => [ 1, 2, 3 ] } )->run($conn);
 
diff --git a/t/document.t b/t/document.t
index 49b6717..8dec517 100644
--- a/t/document.t
+++ b/t/document.t
@@ -226,6 +226,54 @@ $res = r->table('marvel')->get('Iron Man')->bracket('equipment')
 is $res->type, 1, 'Correct response type';
 is_deeply $res->response, ['oldHelm'];
 
+# get_field
+$res = r->table('marvel')->get('Iron Man')->get_field('reactorState')->run;
+
+is $res->type,     1,        'Correct response type';
+is $res->response, 'medium', 'Correct response';
+
+$res = r->table('marvel')->get_field('superpower')->run;
+
+is $res->type, 2, 'Correct response type';
+is_deeply [sort @{$res->response}],
+  [
+  'Adamantium', 'Bio-lasers', 'Bow-n-arrow', 'God-like powers',
+  'Size',       'Smash',      'Spidy Sense', 'Super Strength',
+  ],
+  'Correct response';
+
+# bracket
+$res = r->table('marvel')->get('Iron Man')->bracket('reactorState')->run;
+
+is $res->type,     1,        'Correct response type';
+is $res->response, 'medium', 'Correct response';
+
+$res = r->table('marvel')->bracket('superpower')->run;
+
+is $res->type, 2, 'Correct response type';
+is_deeply [sort @{$res->response}],
+  [
+  'Adamantium', 'Bio-lasers', 'Bow-n-arrow', 'God-like powers',
+  'Size',       'Smash',      'Spidy Sense', 'Super Strength',
+  ],
+  'Correct response';
+
+# attr - depercated
+$res = r->table('marvel')->get('Iron Man')->attr('reactorState')->run;
+
+is $res->type,     1,        'Correct response type';
+is $res->response, 'medium', 'Correct response';
+
+$res = r->table('marvel')->attr('superpower')->run;
+
+is $res->type, 2, 'Correct response type';
+is_deeply [sort @{$res->response}],
+  [
+  'Adamantium', 'Bio-lasers', 'Bow-n-arrow', 'God-like powers',
+  'Size',       'Smash',      'Spidy Sense', 'Super Strength',
+  ],
+  'Correct response';
+
 # Plucks out one or more attributes from either an object or a sequence of
 # objects (projection).
 $res = r->table('marvel')->get('Iron Man')
diff --git a/t/string.t b/t/string.t
index f96810d..7a26196 100644
--- a/t/string.t
+++ b/t/string.t
@@ -23,4 +23,31 @@ isa_ok $res, 'Rethinkdb::Response';
 is $res->type,     1,     'Correct status code';
 is $res->response, undef, 'Correct number of updates';
 
+# split
+$res = r->expr('foo  bar bax')->split->run($conn);
+
+isa_ok $res, 'Rethinkdb::Response';
+is $res->type,     1,     'Correct status code';
+is_deeply $res->response, ['foo', 'bar', 'bax'], 'Correct split response';
+
+$res = r->expr('id:0,foo:bar,stuff:good')->split(',')->run($conn);
+
+isa_ok $res, 'Rethinkdb::Response';
+is $res->type,     1,     'Correct status code';
+is_deeply $res->response, ['id:0', 'foo:bar', 'stuff:good'], 'Correct split response';
+
+# upcase
+$res = r->expr('Sentence about LaTeX.')->upcase->run($conn);
+
+isa_ok $res, 'Rethinkdb::Response';
+is $res->type,     1,     'Correct status code';
+is $res->response, 'SENTENCE ABOUT LATEX.', 'Correct split response';
+
+# downcase
+$res = r->expr('Sentence about LaTeX.')->downcase->run($conn);
+
+isa_ok $res, 'Rethinkdb::Response';
+is $res->type,     1,     'Correct status code';
+is $res->response, 'sentence about latex.', 'Correct split response';
+
 done_testing();