X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FRelationship%2FBelongsTo.pm;h=535fa751f1541249e191cd55a096f4f9a1f508ab;hb=75d079145a507a0e5ff89b2676d383f4fd1a5511;hp=aca69aa0e1ffb35cec1fab09996f4258d9b2fd45;hpb=103647d504eeadac7d179057e9f4d5eda0cd7c1b;p=dbsrgits%2FDBIx-Class.git

diff --git a/lib/DBIx/Class/Relationship/BelongsTo.pm b/lib/DBIx/Class/Relationship/BelongsTo.pm
index aca69aa..535fa75 100644
--- a/lib/DBIx/Class/Relationship/BelongsTo.pm
+++ b/lib/DBIx/Class/Relationship/BelongsTo.pm
@@ -6,22 +6,34 @@ use warnings;
 sub belongs_to {
   my ($class, $rel, $f_class, $cond, $attrs) = @_;
   eval "require $f_class";
-  my %f_primaries;
-  $f_primaries{$_} = 1 for eval { $f_class->primary_columns };
-  my $f_loaded = !$@;
-  # single key relationship
-  if (not defined $cond) {
-    $class->throw("Can't infer join condition for ${rel} on ${class}; unable to load ${f_class}") unless $f_loaded;
+  if ($@) {
+    $class->throw_exception($@) unless $@ =~ /Can't locate/;
+  }
+  
+  # no join condition or just a column name
+  if (!ref $cond) {
+    my %f_primaries = map { $_ => 1 } eval { $f_class->primary_columns };
+    $class->throw_exception("Can't infer join condition for ${rel} on ${class}; unable to load ${f_class}")
+      if $@;
+
     my ($pri, $too_many) = keys %f_primaries;
-    $class->throw("Can't infer join condition for ${rel} on ${class}; ${f_class} has multiple primary key") if $too_many;
-    my $acc_type = ($class->has_column($rel)) ? 'filter' : 'single';
+    $class->throw_exception("Can't infer join condition for ${rel} on ${class}; ${f_class} has no primary keys")
+      unless defined $pri;
+    $class->throw_exception("Can't infer join condition for ${rel} on ${class}; ${f_class} has multiple primary keys")
+      if $too_many;
+
+    my $fk = defined $cond ? $cond : $rel;
+    $class->throw_exception("Can't infer join condition for ${rel} on ${class}; $fk is not a column")
+      unless $class->has_column($fk);
+
+    my $acc_type = $class->has_column($rel) ? 'filter' : 'single';
     $class->add_relationship($rel, $f_class,
-      { "foreign.${pri}" => "self.${rel}" },
+      { "foreign.${pri}" => "self.${fk}" },
       { accessor => $acc_type, %{$attrs || {}} }
     );
   }
-  # multiple key relationship
-  else {
+  # explicit join condition
+  elsif (ref $cond eq 'HASH') {
     my $cond_rel;
     for (keys %$cond) {
       if (m/\./) { # Explicit join condition
@@ -30,11 +42,15 @@ sub belongs_to {
       }
       $cond_rel->{"foreign.$_"} = "self.".$cond->{$_};
     }
+    my $acc_type = (keys %$cond_rel == 1 and $class->has_column($rel)) ? 'filter' : 'single';
     $class->add_relationship($rel, $f_class,
       $cond_rel,
-      { accessor => 'single', %{$attrs || {}} }
+      { accessor => $acc_type, %{$attrs || {}} }
     );
   }
+  else {
+    $class->throw_exception('third argument for belongs_to must be undef, a column name, or a join condition');
+  }
   return 1;
 }