From: Matt S Trout <mst@shadowcat.co.uk>
Date: Mon, 6 Feb 2006 00:46:41 +0000 (+0000)
Subject: multi-join to same rel works now
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=489709af09215594801ecdbe208f542e0432d0a0;p=dbsrgits%2FDBIx-Class-Historic.git

multi-join to same rel works now
---

diff --git a/Changes b/Changes
index 3f20f63..639470e 100644
--- a/Changes
+++ b/Changes
@@ -1,6 +1,7 @@
 Revision history for DBIx::Class
 
 0.05001
+        - added multi-join (join => [ 'foo', 'foo' ]), aliases second to foo_2
         - hack PK::Auto::Pg for "table" names referencing a schema
         - find() with attributes works
         - added experimental Serialize and ResultSetManager components
diff --git a/lib/DBIx/Class/ResultSet.pm b/lib/DBIx/Class/ResultSet.pm
index 32e4177..799b8d6 100644
--- a/lib/DBIx/Class/ResultSet.pm
+++ b/lib/DBIx/Class/ResultSet.pm
@@ -110,11 +110,10 @@ sub new {
         push(@{$attrs->{from}}, $source->resolve_join($p, $attrs->{alias}))
             unless $seen{$p};
       }
-      my @cols = ();
-      push @cols, $source->resolve_prefetch($p, $attrs->{alias});
+      my @prefetch = $source->resolve_prefetch($p, $attrs->{alias});
       #die Dumper \@cols;
-      push(@{$attrs->{select}}, @cols);
-      push(@{$attrs->{as}}, @cols);
+      push(@{$attrs->{select}}, map { $_->[0] } @prefetch);
+      push(@{$attrs->{as}}, map { $_->[1] } @prefetch);
     }
   }
 
diff --git a/lib/DBIx/Class/ResultSource.pm b/lib/DBIx/Class/ResultSource.pm
index ceb5d36..8ea0b1f 100644
--- a/lib/DBIx/Class/ResultSource.pm
+++ b/lib/DBIx/Class/ResultSource.pm
@@ -352,26 +352,31 @@ Returns the join structure required for the related result source
 =cut
 
 sub resolve_join {
-  my ($self, $join, $alias) = @_;
+  my ($self, $join, $alias, $seen) = @_;
+  $seen ||= {};
   if (ref $join eq 'ARRAY') {
-    return map { $self->resolve_join($_, $alias) } @$join;
+    return map { $self->resolve_join($_, $alias, $seen) } @$join;
   } elsif (ref $join eq 'HASH') {
-    return map { $self->resolve_join($_, $alias),
-                 $self->related_source($_)->resolve_join($join->{$_}, $_) }
+    return
+      map { $self->resolve_join($_, $alias, $seen),
+            $self->related_source($_)->resolve_join($join->{$_}, $_, $seen) }
            keys %$join;
   } elsif (ref $join) {
     $self->throw_exception("No idea how to resolve join reftype ".ref $join);
   } else {
+    my $count = ++$seen->{$join};
+    #use Data::Dumper; warn Dumper($seen);
+    my $as = ($count > 1 ? "${join}_${count}" : $join);
     my $rel_info = $self->relationship_info($join);
     $self->throw_exception("No such relationship ${join}") unless $rel_info;
     my $type = $rel_info->{attrs}{join_type} || '';
-    return [ { $join => $self->related_source($join)->from,
+    return [ { $as => $self->related_source($join)->from,
                -join_type => $type },
-             $self->resolve_condition($rel_info->{cond}, $join, $alias) ];
+             $self->resolve_condition($rel_info->{cond}, $as, $alias) ];
   }
 }
 
-=head2 resolve_condition($cond, $rel, $alias|$object)
+=head2 resolve_condition($cond, $as, $alias|$object)
 
 Resolves the passed condition to a concrete query fragment. If given an alias,
 returns a join condition; if given an object, inverts that object to produce
@@ -380,7 +385,7 @@ a related conditional from that object.
 =cut
 
 sub resolve_condition {
-  my ($self, $cond, $rel, $for) = @_;
+  my ($self, $cond, $as, $for) = @_;
   #warn %$cond;
   if (ref $cond eq 'HASH') {
     my %ret;
@@ -393,12 +398,12 @@ sub resolve_condition {
         $ret{$k} = $for->get_column($v);
         #warn %ret;
       } else {
-        $ret{"${rel}.${k}"} = "${for}.${v}";
+        $ret{"${as}.${k}"} = "${for}.${v}";
       }
     }
     return \%ret;
   } elsif (ref $cond eq 'ARRAY') {
-    return [ map { $self->resolve_condition($_, $rel, $for) } @$cond ];
+    return [ map { $self->resolve_condition($_, $as, $for) } @$cond ];
   } else {
    die("Can't handle this yet :(");
   }
@@ -448,20 +453,21 @@ in the supplied relationships. Examples:
 =cut
 
 sub resolve_prefetch {
-  my( $self, $pre, $alias ) = @_;
+  my ($self, $pre, $alias, $seen) = @_;
+  $seen ||= {};
   use Data::Dumper;
   #$alias ||= $self->name;
   #warn $alias, Dumper $pre;
   if( ref $pre eq 'ARRAY' ) {
-    return map { $self->resolve_prefetch( $_, $alias ) } @$pre;
+    return map { $self->resolve_prefetch( $_, $alias, $seen ) } @$pre;
   }
   elsif( ref $pre eq 'HASH' ) {
     my @ret =
     map {
-      $self->resolve_prefetch($_, $alias),
-      $self->related_source($_)->resolve_prefetch( $pre->{$_}, $_ )
-    }
-    keys %$pre;
+      $self->resolve_prefetch($_, $alias, $seen),
+      $self->related_source($_)->resolve_prefetch(
+                                   $pre->{$_}, "${alias}.$_", $seen)
+        } keys %$pre;
     #die Dumper \@ret;
     return @ret;
   }
@@ -469,12 +475,15 @@ sub resolve_prefetch {
     $self->throw_exception( "don't know how to resolve prefetch reftype " . ref $pre);
   }
   else {
+    my $count = ++$seen->{$pre};
+    my $as = ($count > 1 ? "${pre}_${count}" : $pre);
     my $rel_info = $self->relationship_info( $pre );
     $self->throw_exception( $self->name . " has no such relationship '$pre'" ) unless $rel_info;
-    my $prefix = $alias && $alias ne 'me' ? "$alias.$pre" : $pre;
-    my @ret = map { "$prefix.$_" } $self->related_source($pre)->columns;
+    my $as_prefix = ($alias =~ /^.*?\.(.*)$/ ? $1.'.' : '');
+    return map { [ "${as}.$_", "${as_prefix}${pre}.$_", ] }
+      $self->related_source($pre)->columns;
     #warn $alias, Dumper (\@ret);
-    return @ret;
+    #return @ret;
   }
 }
 
diff --git a/t/run/16joins.tl b/t/run/16joins.tl
index 3ea71f1..87eaf0a 100644
--- a/t/run/16joins.tl
+++ b/t/run/16joins.tl
@@ -7,7 +7,7 @@ BEGIN {
     eval "use DBD::SQLite";
     plan $@
         ? ( skip_all => 'needs DBD::SQLite for testing' )
-        : ( tests => 33 );
+        : ( tests => 35 );
 }
 
 # test the abstract join => SQL generator
@@ -225,6 +225,15 @@ $rs = $schema->resultset("CD")->search(
 cmp_ok( $rs->count, '==', 3, "count() ok after group_by on related column" );
 
 cmp_ok( scalar $rs->all, '==', 3, "all() returns same count as count() after group_by on related column" );
-}
+
+$rs = $schema->resultset("Artist")->search(
+        { 'cds.title' => 'Spoonful of bees',
+          'cds_2.title' => 'Forkful of bees' },
+        { join => [ 'cds', 'cds' ] });
+
+cmp_ok($rs->count, '==', 1, "single artist returned from multi-join");
+is($rs->next->name, 'Caterwauler McCrae', "Correct artist returned");
+
+} # end run_tests
 
 1;