X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FSQL%2FAbstract%2FExtraClauses.pm;h=c0e753dd75a03fe1a1b1cd99a66c2ab0e266ff6c;hb=ec49a2e10ad2cca513719dc04f410fb9cae85978;hp=00e4d2aea8da406ddb8614b7871309928bc6d792;hpb=ee706e89c8703b720f970a16163d36de9a30e7d4;p=scpubgit%2FQ-Branch.git

diff --git a/lib/SQL/Abstract/ExtraClauses.pm b/lib/SQL/Abstract/ExtraClauses.pm
index 00e4d2a..c0e753d 100644
--- a/lib/SQL/Abstract/ExtraClauses.pm
+++ b/lib/SQL/Abstract/ExtraClauses.pm
@@ -1,68 +1,154 @@
 package SQL::Abstract::ExtraClauses;
 
-use strict;
-use warnings;
-use if $] < '5.010', 'MRO::Compat';
-use mro 'c3';
-use base qw(SQL::Abstract::Clauses);
-
-BEGIN { *puke = \&SQL::Abstract::puke }
-
-sub register_defaults {
-  my $self = shift;
-  $self->next::method(@_);
-  $self->clauses_of(
-    select => $self->clauses_of('select'), qw(group_by having)
-  );
-  $self->clause_expanders(
-    'select.group_by', sub {
-      $_[0]->_expand_maybe_list_expr($_[1], -ident)
-    },
-    'select.having', 'expand_expr',
+use Moo;
+
+has sqla => (
+  is => 'ro', init_arg => undef,
+  handles => [ qw(
+    expand_expr expand_maybe_list_expr render_aqt join_query_parts
+  ) ],
+);
+
+sub cb {
+  my ($self, $method, @args) = @_;
+  return sub {
+    local $self->{sqla} = shift;
+    $self->$method(@args, @_)
+  };
+}
+
+sub register {
+  my ($self, $method, @pairs) = @_;
+  my $sqla = $self->sqla;
+  while (my ($car, $cdr) = splice(@pairs, 0, 2)) {
+    my $cb = $self->cb($cdr);
+    $sqla->$method($car, $cb);
+  }
+  return $self;
+}
+
+sub apply_to {
+  my ($self, $sqla) = @_;
+  $self = $self->new unless ref($self);
+  local $self->{sqla} = $sqla;
+  $self->register_extensions($sqla);
+}
+
+sub register_extensions {
+  my ($self, $sqla) = @_;
+  my @clauses = $sqla->clauses_of('select');
+  my @before_setop;
+  CLAUSE: foreach my $idx (0..$#clauses) {
+    if ($clauses[$idx] eq 'order_by') {
+      @before_setop = @clauses[0..$idx-1];
+      splice(@clauses, $idx, 0, qw(setop group_by having));
+      last CLAUSE;
+    }
+  }
+  die "Huh?" unless @before_setop;
+  $sqla->clauses_of(select => 'with', @clauses);
+  $self->register(
+    clause_expanders =>
+      'select.group_by'
+        => sub { $_[0]->expand_maybe_list_expr($_[2], -ident) },
+      'select.having'
+        => sub { $_[0]->expand_expr($_[2]) },
   );
   foreach my $thing (qw(join from_list)) {
-    $self->expander($thing => "_expand_${thing}")
-         ->renderer($thing => "_render_${thing}")
+    $sqla->expander($thing => $self->cb("_expand_${thing}"))
+         ->renderer($thing => $self->cb("_render_${thing}"))
   }
-  $self->op_expander(as => '_expand_op_as');
-  $self->expander(as => '_expand_op_as');
-  $self->renderer(as => '_render_as');
+  $sqla->binop_expander(as => $self->cb('_expand_op_as'));
+  $sqla->renderer(as => $self->cb('_render_as'));
+  $sqla->expander(alias => $self->cb('_expand_alias'));
+  $sqla->renderer(alias => $self->cb('_render_alias'));
 
-  $self->clauses_of(update => sub {
+  $sqla->clauses_of(update => sub {
     my ($self, @clauses) = @_;
     splice(@clauses, 2, 0, 'from');
     @clauses;
   });
 
-  $self->clauses_of(delete => sub {
+  $sqla->clauses_of(delete => sub {
     my ($self, @clauses) = @_;
     splice(@clauses, 1, 0, 'using');
     @clauses;
   });
 
-  $self->clause_expanders(
-    'update.from' => '_expand_select_clause_from',
-    'delete.using' => sub {
-      +(using => $_[0]->_expand_from_list(undef, $_[1]));
-    },
-    'insert.rowvalues' => sub {
-      +(from => $_[0]->expand_expr({ -values => $_[1] }));
-    },
-    'insert.select' => sub {
-      +(from => $_[0]->expand_expr({ -select => $_[1] }));
-    },
+  $sqla->clause_expanders(
+    'update.from' => $self->cb('_expand_from_list'),
+    'delete.using' => $self->cb('_expand_from_list'),
+    'insert.rowvalues' => $self->cb(sub {
+      +(from => $_[0]->expand_expr({ -values => $_[2] }));
+    }),
+    'insert.select' => $self->cb(sub {
+      +(from => $_[0]->expand_expr({ -select => $_[2] }));
+    }),
   );
-  return $self;
+
+  # set ops
+  $sqla->wrap_expander(select => sub {
+    $self->cb('_expand_select', $_[0], \@before_setop);
+  });
+
+  $sqla->clause_renderer(
+    'select.setop' => $self->cb(sub { $_[0]->render_aqt($_[2]); })
+  );
+
+  foreach my $setop (qw(union intersect except)) {
+    $sqla->expander($setop => $self->cb('_expand_setop'));
+    $sqla->renderer($setop => $self->cb('_render_setop'));
+  }
+
+  my $setop_expander = $self->cb('_expand_clause_setop');
+
+  $sqla->clause_expanders(
+    map +($_ => $setop_expander),
+      map "select.${_}",
+        map +($_, "${_}_all", "${_}_distinct"),
+          qw(union intersect except)
+  );
+
+  my $w_exp = $self->cb('_expand_with');
+  my $w_rdr = $self->cb('_render_with');
+  $sqla->clause_expander('select.with' => $w_exp);
+  $sqla->clause_expander('select.with_recursive' => $w_exp);
+  $sqla->clause_renderer('select.with' => $w_rdr);
+
+  foreach my $stmt (qw(insert update delete)) {
+    $sqla->clauses_of($stmt => 'with', $sqla->clauses_of($stmt));
+    $sqla->clause_expander("${stmt}.$_" => $w_exp)
+      for qw(with with_recursive);
+    $sqla->clause_renderer("${stmt}.with" => $w_rdr);
+  }
+
+  $sqla->expander(cast => $self->cb('_expand_cast'));
+
+  $sqla->clause_expanders(
+    "select.from", $self->cb('_expand_from_list'),
+    "update.target", $self->cb('_expand_update_clause_target'),
+    "update.update", $self->cb('_expand_update_clause_target'),
+  );
+
+  return $sqla;
 }
 
-sub _expand_select_clause_from {
-  my ($self, $from) = @_;
-  +(from => $self->_expand_from_list(undef, $from));
+sub _expand_select {
+  my ($self, $orig, $before_setop, @args) = @_;
+  my $exp = $self->sqla->$orig(@args);
+  return $exp unless my $setop = (my $sel = $exp->{-select})->{setop};
+  if (my @keys = grep $sel->{$_}, @$before_setop) {
+    my %inner; @inner{@keys} = delete @{$sel}{@keys};
+    unshift @{(values(%$setop))[0]{queries}},
+      { -select => \%inner };
+  }
+  return $exp;
 }
 
 sub _expand_from_list {
   my ($self, undef, $args) = @_;
   if (ref($args) eq 'HASH') {
+    return $args if $args->{-from_list};
     return { -from_list => [ $self->expand_expr($args) ] };
   }
   my @list;
@@ -94,13 +180,13 @@ sub _expand_join {
       : (to => $args->[0], @{$args}[1..$#$args])
   );
   if (my $as = delete $proto{as}) {
-    $proto{to} = { -as => [ $proto{to}, ref($as) eq 'ARRAY' ? @$as : $as ] };
+    $proto{to} = $self->expand_expr({ -as => [ $proto{to}, $as ] });
   }
   if (defined($proto{using}) and ref(my $using = $proto{using}) ne 'HASH') {
-    $proto{using} = { -row => [
+    $proto{using} = [
       map [ $self->expand_expr($_, -ident) ],
         ref($using) eq 'ARRAY' ? @$using: $using
-    ] };
+    ];
   }
   my %ret = map +($_ => $self->expand_expr($proto{$_}, -ident)),
               sort keys %proto;
@@ -108,65 +194,261 @@ sub _expand_join {
 }
 
 sub _render_from_list {
-  my ($self, $list) = @_;
-  return $self->_join_parts(', ', map [ $self->render_aqt($_) ], @$list);
+  my ($self, undef, $list) = @_;
+  return $self->join_query_parts(', ', @$list);
 }
 
 sub _render_join {
-  my ($self, $args) = @_;
+  my ($self, undef, $args) = @_;
 
   my @parts = (
-    [ $self->render_aqt($args->{from}) ],
-    [ $self->_sqlcase(
-        ($args->{type}
-          ? join(' ', split '_', $args->{type}).' '
-          : ''
-        )
-        .'join'
-      )
-    ],
-    [ $self->render_aqt(
-        map +($_->{-ident} || $_->{-as} ? $_ : { -row => [ $_ ] }), $args->{to}
-    ) ],
+    $args->{from},
+    { -keyword => join '_', ($args->{type}||()), 'join' },
+    (map +($_->{-ident} || $_->{-as} ? $_ : ('(', $_, ')')), $args->{to}),
     ($args->{on} ? (
-      [ $self->_sqlcase('on') ],
-      [ $self->render_aqt($args->{on}) ],
+      { -keyword => 'on' },
+      $args->{on},
     ) : ()),
     ($args->{using} ? (
-      [ $self->_sqlcase('using') ],
-      [ $self->render_aqt($args->{using}) ],
+      { -keyword => 'using' },
+      '(', $args->{using}, ')',
     ) : ()),
   );
-  return $self->_join_parts(' ', @parts);
+  return $self->join_query_parts(' ', @parts);
 }
 
 sub _expand_op_as {
   my ($self, undef, $vv, $k) = @_;
-  my @as = map $self->expand_expr($_, -ident),
-             (defined($k) ? ($k) : ()), ref($vv) eq 'ARRAY' ? @$vv : $vv;
-  return { -as => \@as };
+  my @vv = (ref($vv) eq 'ARRAY' ? @$vv : $vv);
+  my $ik = $self->expand_expr($k, -ident);
+  return +{ -as => [ $ik, $self->expand_expr($vv[0], -alias) ] }
+    if @vv == 1 and ref($vv[0]) eq 'HASH';
+
+  my @as = map $self->expand_expr($_, -ident), @vv;
+  return { -as => [ $ik, { -alias => \@as } ] };
 }
 
 sub _render_as {
-  my ($self, $args) = @_;
-  my ($thing, $as, @cols) = @$args;
-  return $self->_join_parts(
+  my ($self, undef, $args) = @_;
+  my ($thing, $alias) = @$args;
+  return $self->join_query_parts(
     ' ',
-    [ $self->render_aqt($thing) ],
-    [ $self->_sqlcase('as') ],
-    (@cols
-      ? [ $self->_join_parts('',
-            [ $self->render_aqt($as) ],
-            [ '(' ],
-            [ $self->_join_parts(
-                ', ',
-                map [ $self->render_aqt($_) ], @cols
-            ) ],
-            [ ')' ],
-        ) ]
-      : [ $self->render_aqt($as) ]
-    ),
+    $thing,
+    { -keyword => 'as' },
+    $alias,
   );
 }
 
+sub _render_alias {
+  my ($self, undef, $args) = @_;
+  my ($as, @cols) = @$args;
+  return (@cols
+    ? $self->join_query_parts('',
+         $as,
+         '(',
+         $self->join_query_parts(
+           ', ',
+           @cols
+         ),
+         ')',
+      )
+    : $self->render_aqt($as)
+  );
+}
+
+sub _expand_update_clause_target {
+  my ($self, undef, $target) = @_;
+  +(target => $self->_expand_from_list(undef, $target));
+}
+
+sub _expand_cast {
+  my ($self, undef, $thing) = @_;
+  return { -func => [ cast => $thing ] } if ref($thing) eq 'HASH';
+  my ($cast, $to) = @{$thing};
+  +{ -func => [ cast => { -as => [
+    $self->expand_expr($cast),
+    $self->expand_expr($to, -ident),
+  ] } ] };
+}
+
+sub _expand_alias {
+  my ($self, undef, $args) = @_;
+  if (ref($args) eq 'HASH' and my $alias = $args->{-alias}) {
+    $args = $alias;
+  }
+  +{ -alias => [
+      map $self->expand_expr($_, -ident),
+      ref($args) eq 'ARRAY' ? @{$args} : $args
+    ]
+  }
+}
+
+sub _expand_with {
+  my ($self, $name, $with) = @_;
+  my (undef, $type) = split '_', $name;
+  if (ref($with) eq 'HASH') {
+    return +{
+      %$with,
+      queries => [
+        map +[
+          $self->expand_expr({ -alias => $_->[0] }, -ident),
+          $self->expand_expr($_->[1]),
+        ], @{$with->{queries}}
+      ]
+    }
+  }
+  my @with = @$with;
+  my @exp;
+  while (my ($alias, $query) = splice @with, 0, 2) {
+    push @exp, [
+      $self->expand_expr({ -alias => $alias }, -ident),
+      $self->expand_expr($query)
+    ];
+  }
+  return +(with => { ($type ? (type => $type) : ()), queries => \@exp });
+}
+
+sub _render_with {
+  my ($self, undef, $with) = @_;
+  my $q_part = $self->join_query_parts(', ',
+    map {
+      my ($alias, $query) = @$_;
+      $self->join_query_parts(' ',
+          $alias,
+          { -keyword => 'as' },
+          $query,
+      )
+    } @{$with->{queries}}
+  );
+  return $self->join_query_parts(' ',
+    { -keyword => join '_', 'with', ($with->{type}||'') },
+    $q_part,
+  );
+}
+
+sub _expand_setop {
+  my ($self, $setop, $args) = @_;
+  +{ "-${setop}" => {
+       %$args,
+       queries => [ map $self->expand_expr($_), @{$args->{queries}} ],
+  } };
+}
+
+sub _render_setop {
+  my ($self, $setop, $args) = @_;
+  $self->join_query_parts(
+    { -keyword => ' '.join('_', $setop, ($args->{type}||())).' ' },
+    @{$args->{queries}}
+  );
+}
+
+sub _expand_clause_setop {
+  my ($self, $setop, $args) = @_;
+  my ($op, $type) = split '_', $setop;
+  +(setop => $self->expand_expr({
+    "-${op}" => {
+      ($type ? (type => $type) : ()),
+      queries => (ref($args) eq 'ARRAY' ? $args : [ $args ])
+    }
+  }));
+}
+
 1;
+
+__END__
+
+=head1 NAME
+
+SQL::Abstract::ExtraClauses - new/experimental additions to L<SQL::Abstract>
+
+=head1 SYNOPSIS
+
+  my $sqla = SQL::Abstract->new;
+  SQL::Abstract::ExtraClauses->apply_to($sqla);
+
+=head1 METHODS
+
+=head2 apply_to
+
+Applies the plugin to an L<SQL::Abstract> object.
+
+=head2 cb
+
+For plugin authors, creates a callback to call a method on the plugin.
+
+=head2 sqla
+
+Available only during plugin callback executions, contains the currently
+active L<SQL::Abstract> object.
+
+=head1 NODE TYPES
+
+=head2 alias
+
+Represents a table alias. Expands name and column names with ident as default.
+
+  # expr
+  { -alias => [ 't', 'x', 'y', 'z' ] }
+
+  # aqt
+  { -alias => [
+      { -ident => [ 't' ] }, { -ident => [ 'x' ] },
+      { -ident => [ 'y' ] }, { -ident => [ 'z' ] },
+  ] }
+
+  # query
+  t(x, y, z)
+  []
+
+=head2 as
+
+Represents an sql AS. LHS is expanded with ident as default, RHS is treated
+as a list of arguments for the alias node.
+
+  # expr
+  { foo => { -as => 'bar' } }
+
+  # aqt
+  { -as =>
+      [
+        { -ident => [ 'foo' ] },
+        { -alias => [ { -ident => [ 'bar' ] } ] },
+      ]
+  }
+
+  # query
+  foo AS bar
+  []
+
+  # expr
+  { -as => [ { -select => { _ => 'blah' } }, 't', 'blah' ] }
+
+  # aqt
+  { -as => [
+      { -select =>
+          { select => { -op => [ ',', { -ident => [ 'blah' ] } ] } }
+      },
+      { -alias => [ { -ident => [ 't' ] }, { -ident => [ 'blah' ] } ] },
+  ] }
+
+  # query
+  (SELECT blah) AS t(blah)
+  []
+
+=head2 cast
+
+  # expr
+  { -cast => [ { -ident => 'birthday' }, 'date' ] }
+
+  # aqt
+  { -func => [
+      'cast', {
+        -as => [ { -ident => [ 'birthday' ] }, { -ident => [ 'date' ] } ]
+      },
+  ] }
+
+  # query
+  CAST(birthday AS date)
+  []
+
+=cut