Generate one-to-one accessors for unique foreign keys

diff --git a/lib/DBIx/Class/Schema/Loader/Base.pm b/lib/DBIx/Class/Schema/Loader/Base.pm
index 77695c0..2d1b8fa 100644 (file)
--- a/lib/DBIx/Class/Schema/Loader/Base.pm
+++ b/lib/DBIx/Class/Schema/Loader/Base.pm
@@ -666,9 +666,10 @@ sub _load_relationships {
         $fkdef->{remote_source} =
             $self->monikers->{delete $fkdef->{remote_table}};
     }
+    my $tbl_uniq_info = $self->_table_uniq_info($table);
 
     my $local_moniker = $self->monikers->{$table};
-    my $rel_stmts = $self->{relbuilder}->generate_code($local_moniker, $tbl_fk_info);
+    my $rel_stmts = $self->{relbuilder}->generate_code($local_moniker, $tbl_fk_info, $tbl_uniq_info);
 
     foreach my $src_class (sort keys %$rel_stmts) {
         my $src_stmts = $rel_stmts->{$src_class};

diff --git a/lib/DBIx/Class/Schema/Loader/RelBuilder.pm b/lib/DBIx/Class/Schema/Loader/RelBuilder.pm
index 196d09e..a292f2d 100644 (file)
--- a/lib/DBIx/Class/Schema/Loader/RelBuilder.pm
+++ b/lib/DBIx/Class/Schema/Loader/RelBuilder.pm
@@ -121,8 +121,19 @@ sub _inflect_singular {
     return Lingua::EN::Inflect::Number::to_S($relname);
 }
 
+sub _array_eq {
+    my ($a, $b) = @_;
+
+    return unless @$a == @$b;
+
+    for (my $i = 0; $i < @$a; $i++) {
+        return unless $a->[$i] eq $b->[$i];
+    }
+    return 1;
+}
+
 sub generate_code {
-    my ($self, $local_moniker, $rels) = @_;
+    my ($self, $local_moniker, $rels, $uniqs) = @_;
 
     my $all_code = {};
 
@@ -187,6 +198,16 @@ sub generate_code {
             delete $rev_cond{$_};
         }
 
+        my $remote_method = 'has_many';
+
+        # If the local columns have a UNIQUE constraint, this is a one-to-one rel
+        my $primary = [ $self->{schema}->source($local_moniker)->primary_columns ];
+        if (_array_eq($primary, $local_cols) ||
+            grep { _array_eq($_->[1], $local_cols) } @$uniqs) {
+            $remote_method = 'might_have';
+            $local_relname = $self->_inflect_singular($local_relname);
+        }
+
         push(@{$all_code->{$local_class}},
             { method => 'belongs_to',
               args => [ $remote_relname,
@@ -197,7 +218,7 @@ sub generate_code {
         );
 
         push(@{$all_code->{$remote_class}},
-            { method => 'has_many',
+            { method => $remote_method,
               args => [ $local_relname,
                         $local_class,
                         \%rev_cond,

diff --git a/t/lib/dbixcsl_common_tests.pm b/t/lib/dbixcsl_common_tests.pm
index ac32964..2495b3b 100644 (file)
--- a/t/lib/dbixcsl_common_tests.pm
+++ b/t/lib/dbixcsl_common_tests.pm
@@ -43,7 +43,7 @@ sub _monikerize {
 sub run_tests {
     my $self = shift;
 
-    plan tests => 88;
+    plan tests => 97;
 
     $self->create();
 
@@ -310,6 +310,18 @@ sub run_tests {
         my $class26   = $classes->{loader_test26};
         my $rsobj26   = $conn->resultset($moniker26);
 
+        my $moniker27 = $monikers->{loader_test27};
+        my $class27   = $classes->{loader_test27};
+        my $rsobj27   = $conn->resultset($moniker27);
+
+        my $moniker28 = $monikers->{loader_test28};
+        my $class28   = $classes->{loader_test28};
+        my $rsobj28   = $conn->resultset($moniker28);
+
+        my $moniker29 = $monikers->{loader_test29};
+        my $class29   = $classes->{loader_test29};
+        my $rsobj29   = $conn->resultset($moniker29);
+
         isa_ok( $rsobj3, "DBIx::Class::ResultSet" );
         isa_ok( $rsobj4, "DBIx::Class::ResultSet" );
         isa_ok( $rsobj5, "DBIx::Class::ResultSet" );
@@ -326,6 +338,9 @@ sub run_tests {
         isa_ok( $rsobj22, "DBIx::Class::ResultSet" );
         isa_ok( $rsobj25, "DBIx::Class::ResultSet" );
         isa_ok( $rsobj26, "DBIx::Class::ResultSet" );
+        isa_ok( $rsobj27, "DBIx::Class::ResultSet" );
+        isa_ok( $rsobj28, "DBIx::Class::ResultSet" );
+        isa_ok( $rsobj29, "DBIx::Class::ResultSet" );
 
         # basic rel test
         my $obj4 = $rsobj4->find(123);
@@ -384,6 +399,20 @@ sub run_tests {
         isa_ok($rs_rel26->first, $class26);
         is($rs_rel26->first->id, 3);
 
+        # test one-to-one rels
+        my $obj27 = $rsobj27->find(1);
+        my $obj28 = $obj27->loader_test28;
+        isa_ok($obj28, $class28);
+        is($obj28->get_column('id'), 1);
+
+        my $obj29 = $obj27->loader_test29;
+        isa_ok($obj29, $class29);
+        is($obj29->id, 1);
+
+        $obj27 = $rsobj27->find(2);
+        is($obj27->loader_test28, undef);
+        is($obj27->loader_test29, undef);
+
         # from Chisel's tests...
         SKIP: {
             if($self->{vendor} =~ /sqlite/i) {
@@ -758,6 +787,34 @@ sub create {
 
         q{ INSERT INTO loader_test26 (id,rel1,rel2) VALUES (33,5,7) },
         q{ INSERT INTO loader_test26 (id,rel1,rel2) VALUES (3,42,42) },
+
+        qq{
+            CREATE TABLE loader_test27 (
+                id INTEGER NOT NULL PRIMARY KEY
+            ) $self->{innodb}
+        },
+
+        q{ INSERT INTO loader_test27 (id) VALUES (1) },
+        q{ INSERT INTO loader_test27 (id) VALUES (2) },
+
+        qq{
+            CREATE TABLE loader_test28 (
+                id INTEGER NOT NULL PRIMARY KEY,
+                FOREIGN KEY (id) REFERENCES loader_test27 (id)
+            ) $self->{innodb}
+        },
+
+        q{ INSERT INTO loader_test28 (id) VALUES (1) },
+
+        qq{
+            CREATE TABLE loader_test29 (
+                id INTEGER NOT NULL PRIMARY KEY,
+                fk INTEGER UNIQUE,
+                FOREIGN KEY (fk) REFERENCES loader_test27 (id)
+            ) $self->{innodb}
+        },
+
+        q{ INSERT INTO loader_test29 (id,fk) VALUES (1,1) },
     );
 
     my @statements_advanced = (
@@ -884,6 +941,9 @@ sub drop_tables {
         loader_test21
         loader_test26
         loader_test25
+        loader_test28
+        loader_test29
+        loader_test27
     /;
 
     my @tables_advanced = qw/