Consolidate single-pk checks from relationship inferrence codepaths

[dbsrgits/DBIx-Class.git] / lib / DBIx / Class / Relationship / HasOne.pm

diff --git a/lib/DBIx/Class/Relationship/HasOne.pm b/lib/DBIx/Class/Relationship/HasOne.pm
index 4c910b8..57885b3 100644 (file)
--- a/lib/DBIx/Class/Relationship/HasOne.pm
+++ b/lib/DBIx/Class/Relationship/HasOne.pm
@@ -3,8 +3,11 @@ package # hide from PAUSE
 
 use strict;
 use warnings;
+use DBIx::Class::Carp;
+use Try::Tiny;
+use namespace::clean;
 
-our %_pod_inherit_config = 
+our %_pod_inherit_config =
   (
    class_map => { 'DBIx::Class::Relationship::HasOne' => 'DBIx::Class::Relationship' }
   );
@@ -21,46 +24,63 @@ sub _has_one {
   my ($class, $join_type, $rel, $f_class, $cond, $attrs) = @_;
   unless (ref $cond) {
     $class->ensure_class_loaded($f_class);
-    my ($pri, $too_many) = $class->primary_columns;
 
-    $class->throw_exception(
-      "might_have/has_one can only infer join for a single primary key; ".
-      "${class} has more"
-    ) if $too_many;
-
-    $class->throw_exception(
-      "might_have/has_one needs a primary key  to infer a join; ".
-      "${class} has none"
-    ) if !defined $pri && (!defined $cond || !length $cond);
+    my $pri = $class->result_source_instance->_single_pri_col_or_die;
 
-    my $f_class_loaded = eval { $f_class->columns };
+    my $f_class_loaded = try { $f_class->columns };
     my ($f_key,$guess);
     if (defined $cond && length $cond) {
       $f_key = $cond;
       $guess = "caller specified foreign key '$f_key'";
     } elsif ($f_class_loaded && $f_class->has_column($rel)) {
       $f_key = $rel;
-      $guess = "using given relationship '$rel' for foreign key";
-    } else {
-      ($f_key, $too_many) = $f_class->primary_columns;
-      $class->throw_exception(
-        "might_have/has_one can only infer join for a single primary key; ".
-        "${f_class} has more"
-      ) if $too_many;
+      $guess = "using given relationship name '$rel' as foreign key column name";
+    } elsif ($f_class_loaded and my $f_pri = try {
+      $f_class->result_source_instance->_single_pri_col_or_die
+    }) {
+      $f_key = $f_pri;
       $guess = "using primary key of foreign class for foreign key";
     }
+
     $class->throw_exception(
-      "No such column ${f_key} on foreign class ${f_class} ($guess)"
+      "No such column '$f_key' on foreign class ${f_class} ($guess)"
     ) if $f_class_loaded && !$f_class->has_column($f_key);
+
     $cond = { "foreign.${f_key}" => "self.${pri}" };
   }
+  $class->_validate_has_one_condition($cond);
+
+  my $default_cascade = ref $cond eq 'CODE' ? 0 : 1;
+
   $class->add_relationship($rel, $f_class,
    $cond,
    { accessor => 'single',
-     cascade_update => 1, cascade_delete => 1,
+     cascade_update => $default_cascade,
+     cascade_delete => $default_cascade,
      ($join_type ? ('join_type' => $join_type) : ()),
      %{$attrs || {}} });
   1;
 }
 
+sub _validate_has_one_condition {
+  my ($class, $cond )  = @_;
+
+  return if $ENV{DBIC_DONT_VALIDATE_RELS};
+  return unless 'HASH' eq ref $cond;
+  foreach my $foreign_id ( keys %$cond ) {
+    my $self_id = $cond->{$foreign_id};
+
+    # we can ignore a bad $self_id because add_relationship handles this
+    # warning
+    return unless $self_id =~ /^self\.(.*)$/;
+    my $key = $1;
+    $class->throw_exception("Defining rel on ${class} that includes '$key' but no such column defined here yet")
+        unless $class->has_column($key);
+    my $column_info = $class->column_info($key);
+    if ( $column_info->{is_nullable} ) {
+      carp(qq'"might_have/has_one" must not be on columns with is_nullable set to true ($class/$key). This might indicate an incorrect use of those relationship helpers instead of belongs_to.');
+    }
+  }
+}
+
 1;