From: Peter Rabbitson <ribasushi@cpan.org>
Date: Mon, 8 Feb 2010 11:42:09 +0000 (+0000)
Subject: Merge fix of RT54039 from prefetch branch
X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=commitdiff_plain;h=13d0694958bdf4711743bc0c9b70f8a9d7e93522;p=dbsrgits%2FDBIx-Class-Historic.git

Merge fix of RT54039 from prefetch branch
---

diff --git a/Changes b/Changes
index 36bb1ac..2ba69d7 100644
--- a/Changes
+++ b/Changes
@@ -1,6 +1,7 @@
 Revision history for DBIx::Class
 
-        - Fix a bug causing UTF8 columns not to be decoded (RT #54395)
+        - Fix a bug causing UTF8 columns not to be decoded (RT#54395)
+        - Fix bug in One->Many->One prefetch-collapse handling (RT#54039)
         - Cleanup handling of relationship accessor types
 
 0.08117 2010-02-05 17:10:00 (UTC)
diff --git a/lib/DBIx/Class/Row.pm b/lib/DBIx/Class/Row.pm
index e4a1865..eafafe9 100644
--- a/lib/DBIx/Class/Row.pm
+++ b/lib/DBIx/Class/Row.pm
@@ -1062,9 +1062,10 @@ sub inflate_result {
   my ($source_handle) = $source;
 
   if ($source->isa('DBIx::Class::ResultSourceHandle')) {
-      $source = $source_handle->resolve
-  } else {
-      $source_handle = $source->handle
+    $source = $source_handle->resolve
+  } 
+  else {
+    $source_handle = $source->handle
   }
 
   my $new = {
@@ -1073,17 +1074,29 @@ sub inflate_result {
   };
   bless $new, (ref $class || $class);
 
-  my $schema;
   foreach my $pre (keys %{$prefetch||{}}) {
-    my $pre_val = $prefetch->{$pre};
-    my $pre_source = $source->related_source($pre);
-    $class->throw_exception("Can't prefetch non-existent relationship ${pre}")
-      unless $pre_source;
-    if (ref($pre_val->[0]) eq 'ARRAY') { # multi
-      my @pre_objects;
 
-      for my $me_pref (@$pre_val) {
+    my $pre_source = $source->related_source($pre)
+      or $class->throw_exception("Can't prefetch non-existent relationship ${pre}");
+
+    my $accessor = $source->relationship_info($pre)->{attrs}{accessor}
+      or $class->throw_exception("No accessor for prefetched $pre");
+
+    my @pre_vals;
+    if (ref $prefetch->{$pre}[0] eq 'ARRAY') {
+      @pre_vals = @{$prefetch->{$pre}};
+    }
+    elsif ($accessor eq 'multi') {
+      $class->throw_exception("Implicit prefetch (via select/columns) not supported with accessor 'multi'");
+    }
+    else {
+      @pre_vals = $prefetch->{$pre};
+    }
+
+    my @pre_objects;
+    for my $me_pref (@pre_vals) {
 
+        # FIXME - this should not be necessary
         # the collapser currently *could* return bogus elements with all
         # columns set to undef
         my $has_def;
@@ -1098,31 +1111,16 @@ sub inflate_result {
         push @pre_objects, $pre_source->result_class->inflate_result(
           $pre_source, @$me_pref
         );
-      }
-
-      $new->related_resultset($pre)->set_cache(\@pre_objects);
-    } elsif (defined $pre_val->[0]) {
-      my $fetched;
-      unless ($pre_source->primary_columns == grep { exists $pre_val->[0]{$_}
-         and !defined $pre_val->[0]{$_} } $pre_source->primary_columns)
-      {
-        $fetched = $pre_source->result_class->inflate_result(
-                      $pre_source, @{$pre_val});
-      }
-      my $acc_type = $source->relationship_info($pre)->{attrs}{accessor}
-        or $class->throw_exception("No accessor type for prefetched $pre");
+    }
 
-      if ($acc_type eq 'single') {
-        $new->{_relationship_data}{$pre} = $fetched;
-      }
-      elsif ($acc_type eq 'filter') {
-        $new->{_inflated_column}{$pre} = $fetched;
-      }
-      else {
-       $class->throw_exception("Implicit prefetch (via select/columns) not supported with accessor type '$acc_type'");
-      }
-      $new->related_resultset($pre)->set_cache([ $fetched ]);
+    if ($accessor eq 'single') {
+      $new->{_relationship_data}{$pre} = $pre_objects[0];
     }
+    elsif ($accessor eq 'filter') {
+      $new->{_inflated_column}{$pre} = $pre_objects[0];
+    }
+
+    $new->related_resultset($pre)->set_cache(\@pre_objects);
   }
 
   $new->in_storage (1);
diff --git a/t/prefetch/one_to_many_to_one.t b/t/prefetch/one_to_many_to_one.t
new file mode 100644
index 0000000..daa76bd
--- /dev/null
+++ b/t/prefetch/one_to_many_to_one.t
@@ -0,0 +1,35 @@
+use strict;
+use warnings;
+
+use Test::More;
+use Test::Exception;
+
+use lib qw(t/lib);
+use DBICTest;
+
+my $schema = DBICTest->init_schema();
+
+my $artist = $schema->resultset ('Artist')->find ({artistid => 1});
+is ($artist->cds->count, 3, 'Correct number of CDs');
+is ($artist->cds->search_related ('genre')->count, 1, 'Only one of the cds has a genre');
+
+my $queries = 0;
+my $orig_cb = $schema->storage->debugcb;
+$schema->storage->debugcb(sub { $queries++ });
+$schema->storage->debug(1);
+
+
+my $pref = $schema->resultset ('Artist')
+                     ->search ({ 'me.artistid' => $artist->id }, { prefetch => { cds => 'genre' } })
+                      ->next;
+
+is ($pref->cds->count, 3, 'Correct number of CDs prefetched');
+is ($pref->cds->search_related ('genre')->count, 1, 'Only one of the prefetched cds has a prefetched genre');
+
+
+is ($queries, 1, 'All happened within one query only');
+$schema->storage->debugcb($orig_cb);
+$schema->storage->debug(0);
+
+
+done_testing;