X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FDBIx%2FClass%2FRelationship%2FBelongsTo.pm;h=b871266500d85be05a6afdf18a8991d1d47ce66c;hb=4d3a827d3c6009bbea3e08175dde81a0e4d96474;hp=ef6f904ea84aa78749b9f3c2f25558380ca28994;hpb=bfab575afa37545ee175b824cea554c9c37ab6f5;p=dbsrgits%2FDBIx-Class.git

diff --git a/lib/DBIx/Class/Relationship/BelongsTo.pm b/lib/DBIx/Class/Relationship/BelongsTo.pm
index ef6f904..b871266 100644
--- a/lib/DBIx/Class/Relationship/BelongsTo.pm
+++ b/lib/DBIx/Class/Relationship/BelongsTo.pm
@@ -1,38 +1,46 @@
-package DBIx::Class::Relationship::BelongsTo;
+package # hide from PAUSE
+    DBIx::Class::Relationship::BelongsTo;
+
+# Documentation for these methods can be found in
+# DBIx::Class::Relationship
 
 use strict;
 use warnings;
 
 sub belongs_to {
   my ($class, $rel, $f_class, $cond, $attrs) = @_;
-  eval "require $f_class";
-  if ($@) {
-    $class->throw($@) unless $@ =~ /Can't locate/;
-  }
-
-  my %f_primaries;
-  $f_primaries{$_} = 1 for eval { $f_class->primary_columns };
-  my $f_loaded = !$@;
-  
-  # single key relationship
+  # no join condition or just a column name
   if (!ref $cond) {
-    my ($pri,$too_many);
-    if (!defined $cond) {
-      $class->throw("Can't infer join condition for ${rel} on ${class}; unable to load ${f_class}") unless $f_loaded;
-      ($pri, $too_many) = keys %f_primaries;
-      $class->throw("Can't infer join condition for ${rel} on ${class}; ${f_class} has no primary keys") unless defined $pri;      
-      $class->throw("Can't infer join condition for ${rel} on ${class}; ${f_class} has multiple primary key") if $too_many;      
-    }
-    else {
-      $pri = $cond;
-    }
-    my $acc_type = ($class->has_column($rel)) ? 'filter' : 'single';
+    $class->ensure_class_loaded($f_class);
+    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_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 of $class"
+    ) 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
+  # explicit join condition
   elsif (ref $cond eq 'HASH') {
     my $cond_rel;
     for (keys %$cond) {
@@ -42,13 +50,19 @@ 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('third argument for belongs_to must be undef, a column name, or a join condition');
+    $class->throw_exception(
+      'third argument for belongs_to must be undef, a column name, '.
+      'or a join condition'
+    );
   }
   return 1;
 }