Fold column_info() into columns_info()

[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 bca5e5b..46e18e3 100644 (file)
--- a/lib/DBIx/Class/Relationship/HasOne.pm
+++ b/lib/DBIx/Class/Relationship/HasOne.pm
@@ -1,7 +1,17 @@
-package DBIx::Class::Relationship::HasOne;
+package # hide from PAUSE
+    DBIx::Class::Relationship::HasOne;
 
 use strict;
 use warnings;
+use DBIx::Class::Carp;
+use Try::Tiny;
+use DBIx::Class::_Util 'dbic_internal_try';
+use namespace::clean;
+
+our %_pod_inherit_config =
+  (
+   class_map => { 'DBIx::Class::Relationship::HasOne' => 'DBIx::Class::Relationship' }
+  );
 
 sub might_have {
   shift->_has_one('LEFT' => @_);
@@ -13,41 +23,93 @@ sub has_one {
 
 sub _has_one {
   my ($class, $join_type, $rel, $f_class, $cond, $attrs) = @_;
-  eval "require $f_class";
-  if ($@) {
-    $class->throw($@) unless $@ =~ /Can't locate/;
-  }
-
   unless (ref $cond) {
-    my ($pri, $too_many) = $class->primary_columns;
-    $class->throw( "might_have/has_one can only infer join for a single primary key; ${class} has more" )
-      if $too_many;
-    my $f_key;
-    my $f_class_loaded = eval { $f_class->columns };
-    my $guess;
+    my $pri = $class->result_source_instance->_single_pri_col_or_die;
+
+    my ($f_key,$guess,$f_rsrc);
     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( "might_have/has_one can only infer join for a single primary key; ${f_class} has more" )
-        if $too_many;
-      $guess = "using primary key of foreign class for foreign key";
     }
-    $class->throw("No such column ${f_key} on foreign class ${f_class} ($guess)")
-      if $f_class_loaded && !$f_class->has_column($f_key);
+    else {
+      # at this point we need to load the foreigner, expensive or not
+      $class->ensure_class_loaded($f_class);
+
+      $f_rsrc = dbic_internal_try {
+        my $r = $f_class->result_source_instance;
+        die "There got to be some columns by now... (exception caught and rewritten by catch below)"
+          unless $r->columns;
+        $r;
+      }
+      catch {
+        $class->throw_exception(
+          "Foreign class '$f_class' does not seem to be a Result class "
+        . "(or it simply did not load entirely due to a circular relation chain)"
+        );
+      };
+
+      if ($f_rsrc->has_column($rel)) {
+        $f_key = $rel;
+        $guess = "using given relationship name '$rel' as foreign key column name";
+      }
+      else {
+        $f_key = $f_rsrc->_single_pri_col_or_die;
+        $guess = "using primary key of foreign class for foreign key";
+      }
+    }
+
+# FIXME - this check needs to be moved to schema-composition time...
+#    # only perform checks if the far side was not preloaded above *AND*
+#    # appears to have been loaded by something else (has a rsrc_instance)
+#    if (! $f_rsrc and $f_rsrc = dbic_internal_try { $f_class->result_source_instance }) {
+#      $class->throw_exception(
+#        "No such column '$f_key' on foreign class ${f_class} ($guess)"
+#      ) if !$f_rsrc->has_column($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 => $default_cascade,
+     is_depends_on => 0,
      ($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
+    # exception
+    return unless $self_id =~ /^self\.(.*)$/;
+
+    my $key = $1;
+
+    my $column_info = $class->result_source->columns_info->{$key}
+      or $class->throw_exception(
+        "Defining rel on ${class} that includes '$key' "
+      . 'but no such column defined there yet'
+      );
+
+    carp(
+      "'might_have'/'has_one' must not be used on columns with is_nullable "
+    . "set to true ($class/$key). This almost certainly indicates an "
+    . "incorrect use of these relationship helpers instead of 'belongs_to'"
+    ) if $column_info->{is_nullable};
+  }
+}
+
 1;