Release 0.07037
[dbsrgits/DBIx-Class-Schema-Loader.git] / lib / DBIx / Class / Schema / Loader / RelBuilder.pm
index 5345749..9d76031 100644 (file)
@@ -6,17 +6,19 @@ use base 'Class::Accessor::Grouped';
 use mro 'c3';
 use Carp::Clan qw/^DBIx::Class/;
 use Scalar::Util 'weaken';
+use DBIx::Class::Schema::Loader::Utils qw/split_name slurp_file array_eq/;
+use Try::Tiny;
+use List::Util 'first';
+use List::MoreUtils qw/apply uniq any/;
+use namespace::clean;
 use Lingua::EN::Inflect::Phrase ();
 use Lingua::EN::Tagger ();
-use DBIx::Class::Schema::Loader::Utils 'split_name';
-use File::Slurp 'slurp';
-use Try::Tiny;
+use String::ToIdentifier::EN ();
+use String::ToIdentifier::EN::Unicode ();
 use Class::Unload ();
 use Class::Inspector ();
-use List::MoreUtils 'apply';
-use namespace::clean;
 
-our $VERSION = '0.07010';
+our $VERSION = '0.07037';
 
 # Glossary:
 #
@@ -41,16 +43,17 @@ is module is not (yet) for external use.
 
 =head2 new
 
-Arguments: $base object
+Arguments: $loader object
 
 =head2 generate_code
 
-Arguments: 
-    
-    {
-        local_moniker (scalar) => [ fk_info (arrayref), uniq_info (arrayref) ]
+Arguments:
+
+    [
+        [ local_moniker1 (scalar), fk_info1 (arrayref), uniq_info1 (arrayref) ]
+        [ local_moniker2 (scalar), fk_info2 (arrayref), uniq_info2 (arrayref) ]
         ...
-    }
+    ]
 
 This generates the code for the relationships of each table.
 
@@ -59,14 +62,20 @@ statements.  The fk_info arrayref's contents should take the form:
 
     [
         {
-            local_columns => [ 'col2', 'col3' ],
-            remote_columns => [ 'col5', 'col7' ],
+            local_table    => 'some_table',
+            local_moniker  => 'SomeTable',
+            local_columns  => [ 'col2', 'col3' ],
+            remote_table   => 'another_table_moniker',
             remote_moniker => 'AnotherTableMoniker',
+            remote_columns => [ 'col5', 'col7' ],
         },
         {
-            local_columns => [ 'col1', 'col4' ],
-            remote_columns => [ 'col1', 'col2' ],
+            local_table    => 'some_other_table',
+            local_moniker  => 'SomeOtherTable',
+            local_columns  => [ 'col1', 'col4' ],
+            remote_table   => 'yet_another_table_moniker',
             remote_moniker => 'YetAnotherTableMoniker',
+            remote_columns => [ 'col1', 'col2' ],
         },
         # ...
     ],
@@ -100,18 +109,19 @@ arguments, like so:
 =cut
 
 __PACKAGE__->mk_group_accessors('simple', qw/
-    base
+    loader
     schema
     inflect_plural
     inflect_singular
     relationship_attrs
     rel_collision_map
+    rel_name_map
     _temp_classes
     __tagger
 /);
 
 sub new {
-    my ( $class, $base ) = @_;
+    my ($class, $loader) = @_;
 
     # from old POD about this constructor:
     # C<$schema_class> should be a schema class name, where the source
@@ -123,23 +133,24 @@ sub new {
     # are better documented in L<DBIx::Class::Schema::Loader::Base>.
 
     my $self = {
-        base               => $base,
-        schema             => $base->schema,
-        inflect_plural     => $base->inflect_plural,
-        inflect_singular   => $base->inflect_singular,
-        relationship_attrs => $base->relationship_attrs,
-        rel_collision_map  => $base->rel_collision_map,
+        loader             => $loader,
+        schema             => $loader->schema,
+        inflect_plural     => $loader->inflect_plural,
+        inflect_singular   => $loader->inflect_singular,
+        relationship_attrs => $loader->relationship_attrs,
+        rel_collision_map  => $loader->rel_collision_map,
+        rel_name_map       => $loader->rel_name_map,
         _temp_classes      => [],
     };
 
-    weaken $self->{base}; #< don't leak
+    weaken $self->{loader}; #< don't leak
 
     bless $self => $class;
 
     # validate the relationship_attrs arg
     if( defined $self->relationship_attrs ) {
-       ref $self->relationship_attrs eq 'HASH'
-           or croak "relationship_attrs must be a hashref";
+        (ref $self->relationship_attrs eq 'HASH' || ref $self->relationship_attrs eq 'CODE')
+            or croak "relationship_attrs must be a hashref or coderef";
     }
 
     return $self;
@@ -152,16 +163,26 @@ sub _inflect_plural {
 
     return '' if !defined $relname || $relname eq '';
 
+    my $result;
+    my $mapped = 0;
+
     if( ref $self->inflect_plural eq 'HASH' ) {
-        return $self->inflect_plural->{$relname}
-            if exists $self->inflect_plural->{$relname};
+        if (exists $self->inflect_plural->{$relname}) {
+            $result = $self->inflect_plural->{$relname};
+            $mapped = 1;
+        }
     }
     elsif( ref $self->inflect_plural eq 'CODE' ) {
         my $inflected = $self->inflect_plural->($relname);
-        return $inflected if $inflected;
+        if ($inflected) {
+            $result = $inflected;
+            $mapped = 1;
+        }
     }
 
-    return $self->_to_PL($relname);
+    return ($result, $mapped) if $mapped;
+
+    return ($self->_to_PL($relname), 0);
 }
 
 # Singularize a relationship name
@@ -170,16 +191,26 @@ sub _inflect_singular {
 
     return '' if !defined $relname || $relname eq '';
 
+    my $result;
+    my $mapped = 0;
+
     if( ref $self->inflect_singular eq 'HASH' ) {
-        return $self->inflect_singular->{$relname}
-            if exists $self->inflect_singular->{$relname};
+        if (exists $self->inflect_singular->{$relname}) {
+            $result = $self->inflect_singular->{$relname};
+            $mapped = 1;
+        }
     }
     elsif( ref $self->inflect_singular eq 'CODE' ) {
         my $inflected = $self->inflect_singular->($relname);
-        return $inflected if $inflected;
+        if ($inflected) {
+            $result = $inflected;
+            $mapped = 1;
+        }
     }
 
-    return $self->_to_S($relname);
+    return ($result, $mapped) if $mapped;
+
+    return ($self->_to_S($relname), 0);
 }
 
 sub _to_PL {
@@ -218,46 +249,58 @@ sub _default_relationship_attrs { +{
     },
 } }
 
-# accessor for options to be passed to each generated relationship
-# type.  take single argument, the relationship type name, and returns
-# either a hashref (if some options are set), or nothing
+# Accessor for options to be passed to each generated relationship type. takes
+# the relationship type name and optionally any attributes from the database
+# (such as FK ON DELETE/UPDATE and DEFERRABLE clauses), and returns a
+# hashref or undef if nothing is set.
+#
+# The attributes from the database override the default attributes, which in
+# turn are overridden by user supplied attributes.
 sub _relationship_attrs {
-    my ( $self, $reltype ) = @_;
+    my ( $self, $reltype, $db_attrs, $params ) = @_;
     my $r = $self->relationship_attrs;
 
     my %composite = (
         %{ $self->_default_relationship_attrs->{$reltype} || {} },
-        %{ $r->{all} || {} }
+        %{ $db_attrs || {} },
+        (
+            ref $r eq 'HASH' ? (
+                %{ $r->{all} || {} },
+                %{ $r->{$reltype} || {} },
+            )
+            :
+            ()
+        ),
     );
 
-    if( my $specific = $r->{$reltype} ) {
-       while( my ($k,$v) = each %$specific ) {
-           $composite{$k} = $v;
-       }
+    if (ref $r eq 'CODE') {
+        $params->{attrs} = \%composite;
+
+        my %ret = %{ $r->(%$params) || {} };
+
+        %composite = %ret if %ret;
     }
-    return \%composite;
+
+    return %composite ? \%composite : undef;
 }
 
-sub _array_eq {
-    my ($self, $a, $b) = @_;
+sub _strip_id_postfix {
+    my ($self, $name) = @_;
 
-    return unless @$a == @$b;
+    $name =~ s/_?(?:id|ref|cd|code|num)\z//i;
 
-    for (my $i = 0; $i < @$a; $i++) {
-        return unless $a->[$i] eq $b->[$i];
-    }
-    return 1;
+    return $name;
 }
 
 sub _remote_attrs {
-    my ($self, $local_moniker, $local_cols) = @_;
+    my ($self, $local_moniker, $local_cols, $fk_attrs, $params) = @_;
 
-    # get our base set of attrs from _relationship_attrs, if present
-    my $attrs = $self->_relationship_attrs('belongs_to') || {};
+    # get our set of attrs from _relationship_attrs, which uses the FK attrs if available
+    my $attrs = $self->_relationship_attrs('belongs_to', $fk_attrs, $params) || {};
 
-    # If the referring column is nullable, make 'belongs_to' an
+    # If any referring column is nullable, make 'belongs_to' an
     # outer join, unless explicitly set by relationship_attrs
-    my $nullable = grep { $self->schema->source($local_moniker)->column_info($_)->{is_nullable} } @$local_cols;
+    my $nullable = first { $self->schema->source($local_moniker)->column_info($_)->{is_nullable} } @$local_cols;
     $attrs->{join_type} = 'LEFT' if $nullable && !defined $attrs->{join_type};
 
     return $attrs;
@@ -266,14 +309,9 @@ sub _remote_attrs {
 sub _sanitize_name {
     my ($self, $name) = @_;
 
-    if (ref $name) {
-        # scalar ref for weird table name (like one containing a '.')
-        ($name = $$name) =~ s/\W+/_/g;
-    }
-    else {
-        # remove 'schema.' prefix if any
-        $name =~ s/^[^.]+\.//;
-    }
+    $name = $self->loader->_to_identifier('relationships', $name, '_');
+
+    $name =~ s/\W+/_/g; # if naming >= 8 to_identifier takes care of it
 
     return $name;
 }
@@ -283,7 +321,7 @@ sub _normalize_name {
 
     $name = $self->_sanitize_name($name);
 
-    my @words = split_name $name;
+    my @words = split_name $name, $self->loader->_get_naming_v('relationships');
 
     return join '_', map lc, @words;
 }
@@ -296,12 +334,11 @@ sub _remote_relname {
     # name, to make filter accessors work, but strip trailing _id
     if(scalar keys %{$cond} == 1) {
         my ($col) = values %{$cond};
-        $col = $self->_normalize_name($col);
-        $col =~ s/_id$//;
-        $remote_relname = $self->_inflect_singular($col);
+        $col = $self->_strip_id_postfix($self->_normalize_name($col));
+        ($remote_relname) = $self->_inflect_singular($col);
     }
     else {
-        $remote_relname = $self->_inflect_singular($self->_normalize_name($remote_table));
+        ($remote_relname) = $self->_inflect_singular($self->_normalize_name($remote_table));
     }
 
     return $remote_relname;
@@ -312,9 +349,9 @@ sub _resolve_relname_collision {
 
     return $relname if $relname eq 'id'; # this shouldn't happen, but just in case
 
-    my $table = $self->base->tables->{$moniker};
+    my $table = $self->loader->moniker_to_table->{$moniker};
 
-    if ($self->base->_is_result_class_method($relname, $table)) {
+    if ($self->loader->_is_result_class_method($relname, $table)) {
         if (my $map = $self->rel_collision_map) {
             for my $re (keys %$map) {
                 if (my @matches = $relname =~ /$re/) {
@@ -324,13 +361,12 @@ sub _resolve_relname_collision {
         }
 
         my $new_relname = $relname;
-        while ($self->base->_is_result_class_method($new_relname, $table)) {
+        while ($self->loader->_is_result_class_method($new_relname, $table)) {
             $new_relname .= '_rel'
         }
 
         warn <<"EOF";
-Relationship '$relname' in source '$moniker' for columns '@{[ join ',', @$cols ]}' collides with an inherited method.
-Renaming to '$new_relname'.
+Relationship '$relname' in source '$moniker' for columns '@{[ join ',', @$cols ]}' collides with an inherited method. Renaming to '$new_relname'.
 See "RELATIONSHIP NAME COLLISIONS" in perldoc DBIx::Class::Schema::Loader::Base .
 EOF
 
@@ -342,7 +378,7 @@ EOF
 
 sub generate_code {
     my ($self, $tables) = @_;
-    
+
     # make a copy to destroy
     my @tables = @$tables;
 
@@ -379,19 +415,36 @@ sub generate_code {
 
             my ( $local_relname, $remote_relname, $remote_method ) =
                 $self->_relnames_and_method( $local_moniker, $rel, \%cond,  $uniqs, \%counters );
+            my $local_method  = 'belongs_to';
+
+            ($remote_relname) = $self->_rel_name_map($remote_relname, $local_method, $local_class, $local_moniker, $local_cols, $remote_class, $remote_moniker, $remote_cols);
+            ($local_relname)  = $self->_rel_name_map($local_relname, $remote_method, $remote_class, $remote_moniker, $remote_cols, $local_class, $local_moniker, $local_cols);
 
-            $remote_relname = $self->_resolve_relname_collision($local_moniker,  $local_cols,  $remote_relname);
-            $local_relname  = $self->_resolve_relname_collision($remote_moniker, $remote_cols, $local_relname);
+            $remote_relname   = $self->_resolve_relname_collision($local_moniker,  $local_cols,  $remote_relname);
+            $local_relname    = $self->_resolve_relname_collision($remote_moniker, $remote_cols, $local_relname);
+
+            my $rel_attrs_params = {
+                rel_name      => $remote_relname,
+                rel_type      => $local_method,
+                local_source  => $self->schema->source($local_moniker),
+                remote_source => $self->schema->source($remote_moniker),
+                local_table   => $rel->{local_table},
+                local_cols    => $local_cols,
+                remote_table  => $rel->{remote_table},
+                remote_cols   => $remote_cols,
+            };
 
             push(@{$all_code->{$local_class}},
-                { method => 'belongs_to',
+                { method => $local_method,
                   args => [ $remote_relname,
                             $remote_class,
                             \%cond,
-                            $self->_remote_attrs($local_moniker, $local_cols),
+                            $self->_remote_attrs($local_moniker, $local_cols, $rel->{attrs}, $rel_attrs_params),
                   ],
                   extra => {
-                      moniker => $local_moniker,
+                      local_class    => $local_class,
+                      local_moniker  => $local_moniker,
+                      remote_moniker => $remote_moniker,
                   },
                 }
             );
@@ -402,26 +455,41 @@ sub generate_code {
                 delete $rev_cond{$_};
             }
 
+            $rel_attrs_params = {
+                rel_name      => $local_relname,
+                rel_type      => $remote_method,
+                local_source  => $self->schema->source($remote_moniker),
+                remote_source => $self->schema->source($local_moniker),
+                local_table   => $rel->{remote_table},
+                local_cols    => $remote_cols,
+                remote_table  => $rel->{local_table},
+                remote_cols   => $local_cols,
+            };
+
             push(@{$all_code->{$remote_class}},
                 { method => $remote_method,
                   args => [ $local_relname,
                             $local_class,
                             \%rev_cond,
-                            $self->_relationship_attrs($remote_method),
+                            $self->_relationship_attrs($remote_method, {}, $rel_attrs_params),
                   ],
                   extra => {
-                      moniker => $remote_moniker,
+                      local_class    => $remote_class,
+                      local_moniker  => $remote_moniker,
+                      remote_moniker => $local_moniker,
                   },
                 }
             );
         }
     }
 
+    $self->_generate_m2ms($all_code);
+
     # disambiguate rels with the same name
     foreach my $class (keys %$all_code) {
         my $dups = $self->_duplicates($all_code->{$class});
 
-        $self->_disambiguate($all_code->{$class}, $dups) if $dups;
+        $self->_disambiguate($all_code, $class, $dups) if $dups;
     }
 
     $self->_cleanup;
@@ -429,6 +497,164 @@ sub generate_code {
     return $all_code;
 }
 
+# Find classes with only 2 FKs which are the PK and make many_to_many bridges for them.
+sub _generate_m2ms {
+    my ($self, $all_code) = @_;
+
+    while (my ($class, $rels) = each %$all_code) {
+        next unless (grep $_->{method} eq 'belongs_to', @$rels) == 2;
+
+        my $class1_local_moniker  = $rels->[0]{extra}{remote_moniker};
+        my $class1_remote_moniker = $rels->[1]{extra}{remote_moniker};
+
+        my $class2_local_moniker  = $rels->[1]{extra}{remote_moniker};
+        my $class2_remote_moniker = $rels->[0]{extra}{remote_moniker};
+
+        my $class1 = $rels->[0]{args}[1];
+        my $class2 = $rels->[1]{args}[1];
+
+        my $class1_to_link_table_rel = first {
+            $_->{method} eq 'has_many' && $_->{args}[1] eq $class
+        } @{ $all_code->{$class1} };
+
+        next unless $class1_to_link_table_rel;
+
+        my $class1_to_link_table_rel_name = $class1_to_link_table_rel->{args}[0];
+
+        my $class2_to_link_table_rel = first {
+            $_->{method} eq 'has_many' && $_->{args}[1] eq $class
+        } @{ $all_code->{$class2} };
+
+        next unless $class2_to_link_table_rel;
+
+        my $class2_to_link_table_rel_name = $class2_to_link_table_rel->{args}[0];
+
+        my $class1_link_rel = $rels->[1]{args}[0];
+        my $class2_link_rel = $rels->[0]{args}[0];
+
+        my @class1_from_cols = apply { s/^self\.//i } values %{
+            $class1_to_link_table_rel->{args}[2]
+        };
+
+        my @class1_link_cols = apply { s/^self\.//i } values %{ $rels->[1]{args}[2] };
+
+        my @class1_to_cols = apply { s/^foreign\.//i } keys %{ $rels->[1]{args}[2] };
+
+        my @class2_from_cols = apply { s/^self\.//i } values %{
+            $class2_to_link_table_rel->{args}[2]
+        };
+
+        my @class2_link_cols = apply { s/^self\.//i } values %{ $rels->[0]{args}[2] };
+
+        my @class2_to_cols = apply { s/^foreign\.//i } keys %{ $rels->[0]{args}[2] };
+
+        my $link_moniker = $rels->[0]{extra}{local_moniker};
+
+        my @link_table_cols =
+            @{[ $self->schema->source($link_moniker)->columns ]};
+
+        my @link_table_primary_cols =
+            @{[ $self->schema->source($link_moniker)->primary_columns ]};
+
+        next unless @class1_link_cols + @class2_link_cols == @link_table_cols
+            && @link_table_cols == @link_table_primary_cols;
+
+        my ($class1_to_class2_relname) = $self->_rel_name_map(
+            ($self->_inflect_plural($class1_link_rel))[0],
+            'many_to_many',
+            $class1,
+            $class1_local_moniker,
+            \@class1_from_cols,
+            $class2,
+            $class1_remote_moniker,
+            \@class1_to_cols,
+            {
+                link_class => $class,
+                link_moniker => $link_moniker,
+                link_rel_name => $class1_to_link_table_rel_name,
+            },
+        );
+
+        $class1_to_class2_relname = $self->_resolve_relname_collision(
+            $class1_local_moniker,
+            \@class1_from_cols,
+            $class1_to_class2_relname,
+        );
+
+        my ($class2_to_class1_relname) = $self->_rel_name_map(
+            ($self->_inflect_plural($class2_link_rel))[0],
+            'many_to_many',
+            $class1,
+            $class2_local_moniker,
+            \@class2_from_cols,
+            $class2,
+            $class2_remote_moniker,
+            \@class2_to_cols,
+            {
+                link_class => $class,
+                link_moniker => $link_moniker,
+                link_rel_name => $class2_to_link_table_rel_name,
+            },
+        );
+
+        $class2_to_class1_relname = $self->_resolve_relname_collision(
+            $class2_local_moniker,
+            \@class2_from_cols,
+            $class2_to_class1_relname,
+        );
+
+        push @{$all_code->{$class1}}, {
+            method => 'many_to_many',
+            args   => [
+                $class1_to_class2_relname,
+                $class1_to_link_table_rel_name,
+                $class1_link_rel,
+                $self->_relationship_attrs('many_to_many', {}, {
+                    rel_type => 'many_to_many',
+                    rel_name => $class1_to_class2_relname,
+                    local_source => $self->schema->source($class1_local_moniker),
+                    remote_source => $self->schema->source($class1_remote_moniker),
+                    local_table => $self->loader->class_to_table->{$class1},
+                    local_cols => \@class1_from_cols,
+                    remote_table => $self->loader->class_to_table->{$class2},
+                    remote_cols => \@class2_from_cols,
+                }) || (),
+            ],
+            extra  => {
+                local_class    => $class1,
+                link_class     => $class,
+                local_moniker  => $class1_local_moniker,
+                remote_moniker => $class1_remote_moniker,
+            },
+        };
+
+        push @{$all_code->{$class2}}, {
+            method => 'many_to_many',
+            args   => [
+                $class2_to_class1_relname,
+                $class2_to_link_table_rel_name,
+                $class2_link_rel,
+                $self->_relationship_attrs('many_to_many', {}, {
+                    rel_type => 'many_to_many',
+                    rel_name => $class2_to_class1_relname,
+                    local_source => $self->schema->source($class2_local_moniker),
+                    remote_source => $self->schema->source($class2_remote_moniker),
+                    local_table => $self->loader->class_to_table->{$class2},
+                    local_cols => \@class2_from_cols,
+                    remote_table => $self->loader->class_to_table->{$class1},
+                    remote_cols => \@class1_from_cols,
+                }) || (),
+            ],
+            extra  => {
+                local_class    => $class2,
+                link_class     => $class,
+                local_moniker  => $class2_local_moniker,
+                remote_moniker => $class2_remote_moniker,
+            },
+        };
+    }
+}
+
 sub _duplicates {
     my ($self, $rels) = @_;
 
@@ -473,14 +699,59 @@ sub _adjectives {
     return @adjectives;
 }
 
+sub _name_to_identifier {
+    my ($self, $name) = @_;
+
+    my $to_identifier = $self->loader->naming->{force_ascii} ?
+        \&String::ToIdentifier::EN::to_identifier
+        : \&String::ToIdentifier::EN::Unicode::to_identifier;
+
+    return join '_', map lc, split_name $to_identifier->($name, '_');
+}
+
 sub _disambiguate {
-    my ($self, $all_rels, $dups) = @_;
+    my ($self, $all_code, $in_class, $dups) = @_;
 
-    foreach my $dup (keys %$dups) {
+    DUP: foreach my $dup (keys %$dups) {
         my @rels = @{ $dups->{$dup} };
 
+        # Check if there are rels to the same table name in different
+        # schemas/databases, if so qualify them.
+        my @tables = map $self->loader->moniker_to_table->{$_->{extra}{remote_moniker}},
+                        @rels;
+
+        # databases are different, prepend database
+        if ($tables[0]->can('database') && (uniq map $_->database||'', @tables) > 1) {
+            # If any rels are in the same database, we have to distinguish by
+            # both schema and database.
+            my %db_counts;
+            $db_counts{$_}++ for map $_->database, @tables;
+            my $use_schema = any { $_ > 1 } values %db_counts;
+
+            foreach my $i (0..$#rels) {
+                my $rel   = $rels[$i];
+                my $table = $tables[$i];
+
+                $rel->{args}[0] = $self->_name_to_identifier($table->database)
+                    . ($use_schema ? ('_' . $self->name_to_identifier($table->schema)) : '')
+                    . '_' . $rel->{args}[0];
+            }
+            next DUP;
+        }
+        # schemas are different, prepend schema
+        elsif ((uniq map $_->schema||'', @tables) > 1) {
+            foreach my $i (0..$#rels) {
+                my $rel   = $rels[$i];
+                my $table = $tables[$i];
+
+                $rel->{args}[0] = $self->_name_to_identifier($table->schema)
+                    . '_' . $rel->{args}[0];
+            }
+            next DUP;
+        }
+
         foreach my $rel (@rels) {
-            next if $rel->{method} eq 'belongs_to';
+            next if $rel->{method} =~ /^(?:belongs_to|many_to_many)\z/;
 
             my @to_cols = apply { s/^foreign\.//i }
                 keys %{ $rel->{args}[2] };
@@ -494,7 +765,7 @@ sub _disambiguate {
 
             if ((not @adjectives)
                 && (grep { $_->{method} eq 'might_have'
-                           && $_->{args}[1] eq $to_class } @$all_rels) == 1) {
+                           && $_->{args}[1] eq $to_class } @{ $all_code->{$in_class} }) == 1) {
 
                 @adjectives = 'active';
             }
@@ -502,17 +773,21 @@ sub _disambiguate {
             if (@adjectives) {
                 my $rel_name = join '_', sort(@adjectives), $rel->{args}[0];
 
-                $rel_name = $rel->{method} eq 'might_have' ?
+                ($rel_name) = $rel->{method} eq 'might_have' ?
                     $self->_inflect_singular($rel_name)
                     :
                     $self->_inflect_plural($rel_name);
 
-                my $moniker = $rel->{extra}{moniker};
+                my ($local_class, $local_moniker, $remote_moniker)
+                    = @{ $rel->{extra} }
+                        {qw/local_class local_moniker remote_moniker/};
 
                 my @from_cols = apply { s/^self\.//i }
                     values %{ $rel->{args}[2] };
 
-                $rel_name = $self->_resolve_relname_collision($moniker, \@from_cols, $rel_name);
+                ($rel_name) = $self->_rel_name_map($rel_name, $rel->{method}, $local_class, $local_moniker, \@from_cols, $to_class, $remote_moniker, \@to_cols);
+
+                $rel_name = $self->_resolve_relname_collision($local_moniker, \@from_cols, $rel_name);
 
                 $rel->{args}[0] = $rel_name;
             }
@@ -521,40 +796,74 @@ sub _disambiguate {
 
     # Check again for duplicates, since the heuristics above may not have resolved them all.
 
-    if ($dups = $self->_duplicates($all_rels)) {
+    if ($dups = $self->_duplicates($all_code->{$in_class})) {
         foreach my $dup (keys %$dups) {
             # sort by method
             my @rels = map $_->[1], sort { $a->[0] <=> $b->[0] } map [
-                ($_->{method} eq 'belongs_to' ? 3 : $_->{method} eq 'has_many' ? 2 : 1), $_
+                {
+                    belongs_to   => 3,
+                    has_many     => 2,
+                    might_have   => 1,
+                    many_to_many => 0,
+                }->{$_->{method}}, $_
             ], @{ $dups->{$dup} };
 
             my $rel_num = 2;
 
             foreach my $rel (@rels[1 .. $#rels]) {
-                my $inflect_type = $rel->{method} eq 'has_many' ?
+                my $inflect_type = $rel->{method} =~ /^(?:many_to_many|has_many)\z/ ?
                     'inflect_plural'
                     :
                     'inflect_singular';
 
                 my $inflect_method = "_$inflect_type";
 
-                my $relname_new_uninflected =
-                    $self->_inflect_singular($rel->{args}[0]) . "_$rel_num";
+                my $relname_new_uninflected = $rel->{args}[0] . "_$rel_num";
 
                 $rel_num++;
 
-                my $relname_new = $self->$inflect_method($relname_new_uninflected);
+                my ($local_class, $local_moniker, $remote_moniker)
+                    = @{ $rel->{extra} }
+                        {qw/local_class local_moniker remote_moniker/};
+
+                my (@from_cols, @to_cols, $to_class);
+
+                if ($rel->{method} eq 'many_to_many') {
+                    @from_cols = apply { s/^self\.//i } values %{
+                        (first { $_->{args}[0] eq $rel->{args}[1] } @{ $all_code->{$local_class} })
+                            ->{args}[2]
+                    };
+                    @to_cols   = apply { s/^foreign\.//i } keys %{
+                        (first { $_->{args}[0] eq $rel->{args}[2] }
+                            @{ $all_code->{ $rel->{extra}{link_class} } })
+                                ->{args}[2]
+                    };
+                    $to_class  = $self->schema->source($remote_moniker)->result_class;
+                }
+                else {
+                    @from_cols = apply { s/^self\.//i }    values %{ $rel->{args}[2] };
+                    @to_cols   = apply { s/^foreign\.//i } keys   %{ $rel->{args}[2] };
+                    $to_class  = $rel->{args}[1];
+                }
 
-                my $moniker = $rel->{extra}{moniker};
+                my ($relname_new, $inflect_mapped) =
+                    $self->$inflect_method($relname_new_uninflected);
 
-                my @from_cols = apply { s/^self\.//i }
-                    values %{ $rel->{args}[2] };
+                my $rel_name_mapped;
+
+                ($relname_new, $rel_name_mapped) = $self->_rel_name_map($relname_new, $rel->{method}, $local_class, $local_moniker, \@from_cols, $to_class, $remote_moniker, \@to_cols);
 
-                warn <<"EOF";
-Could not find a proper name for relationship '$relname_new' in source '$moniker' for columns '@{[ join ',', @from_cols ]}'.
-Supply a value in '$inflect_type' for '$relname_new_uninflected' to name this relationship.
+                my $mapped = $inflect_mapped || $rel_name_mapped;
+
+                warn <<"EOF" unless $mapped;
+Could not find a proper name for relationship '$relname_new' in source
+'$local_moniker' for columns '@{[ join ',', @from_cols ]}'. Supply a value in
+'$inflect_type' for '$relname_new_uninflected' or 'rel_name_map' for
+'$relname_new' to name this relationship.
 EOF
 
+                $relname_new = $self->_resolve_relname_collision($local_moniker, \@from_cols, $relname_new);
+
                 $rel->{args}[0] = $relname_new;
             }
         }
@@ -564,26 +873,26 @@ EOF
 sub _relnames_and_method {
     my ( $self, $local_moniker, $rel, $cond, $uniqs, $counters ) = @_;
 
-    my $remote_moniker = $rel->{remote_source};
-    my $remote_obj     = $self->schema->source( $remote_moniker );
-    my $remote_class   = $self->schema->class(  $remote_moniker );
-    my $remote_relname = $self->_remote_relname( $remote_obj->from, $cond);
+    my $remote_moniker  = $rel->{remote_source};
+    my $remote_obj      = $self->schema->source( $remote_moniker );
+    my $remote_class    = $self->schema->class(  $remote_moniker );
+    my $remote_relname  = $self->_remote_relname( $rel->{remote_table}, $cond);
 
-    my $local_cols     = $rel->{local_columns};
-    my $local_table    = $self->schema->source($local_moniker)->from;
-    my $local_class    = $self->schema->class($local_moniker);
-    my $local_source   = $self->schema->source($local_moniker);
+    my $local_cols      = $rel->{local_columns};
+    my $local_table     = $rel->{local_table};
+    my $local_class     = $self->schema->class($local_moniker);
+    my $local_source    = $self->schema->source($local_moniker);
 
     my $local_relname_uninflected = $self->_normalize_name($local_table);
-    my $local_relname = $self->_inflect_plural($self->_normalize_name($local_table));
+    my ($local_relname) = $self->_inflect_plural($self->_normalize_name($local_table));
 
     my $remote_method = 'has_many';
 
     # If the local columns have a UNIQUE constraint, this is a one-to-one rel
-    if ($self->_array_eq([ $local_source->primary_columns ], $local_cols) ||
-            grep { $self->_array_eq($_->[1], $local_cols) } @$uniqs) {
-        $remote_method = 'might_have';
-        $local_relname = $self->_inflect_singular($local_relname_uninflected);
+    if (array_eq([ $local_source->primary_columns ], $local_cols) ||
+            first { array_eq($_->[1], $local_cols) } @$uniqs) {
+        $remote_method   = 'might_have';
+        ($local_relname) = $self->_inflect_singular($local_relname_uninflected);
     }
 
     # If more than one rel between this pair of tables, use the local
@@ -591,11 +900,11 @@ sub _relnames_and_method {
     if ($counters->{$remote_moniker} > 1) {
         my $relationship_exists = 0;
 
-        if (-f (my $existing_remote_file = $self->base->get_dump_filename($remote_class))) {
+        if (-f (my $existing_remote_file = $self->loader->get_dump_filename($remote_class))) {
             my $class = "${remote_class}Temporary";
 
             if (not Class::Inspector->loaded($class)) {
-                my $code = slurp $existing_remote_file;
+                my $code = slurp_file $existing_remote_file;
 
                 $code =~ s/(?<=package $remote_class)/Temporary/g;
 
@@ -611,7 +920,7 @@ sub _relnames_and_method {
                 my $rel_cols = [ sort { $a cmp $b } apply { s/^foreign\.//i }
                     (keys %{ $class->relationship_info($local_relname)->{cond} }) ];
 
-                $relationship_exists = 1 if $self->_array_eq([ sort @$local_cols ], $rel_cols);
+                $relationship_exists = 1 if array_eq([ sort @$local_cols ], $rel_cols);
             }
         }
 
@@ -619,20 +928,65 @@ sub _relnames_and_method {
             my $colnames = q{_} . $self->_normalize_name(join '_', @$local_cols);
             $remote_relname .= $colnames if keys %$cond > 1;
 
-            $local_relname = $self->_normalize_name($local_table . $colnames);
-            $local_relname =~ s/_id$//;
+            $local_relname = $self->_strip_id_postfix($self->_normalize_name($local_table . $colnames));
 
             $local_relname_uninflected = $local_relname;
-            $local_relname = $self->_inflect_plural($local_relname);
+            ($local_relname) = $self->_inflect_plural($local_relname);
 
             # if colnames were added and this is a might_have, re-inflect
             if ($remote_method eq 'might_have') {
-                $local_relname = $self->_inflect_singular($local_relname_uninflected);
+                ($local_relname) = $self->_inflect_singular($local_relname_uninflected);
             }
         }
     }
 
-    return ( $local_relname, $remote_relname, $remote_method );
+    return ($local_relname, $remote_relname, $remote_method);
+}
+
+sub _rel_name_map {
+    my ($self, $relname, $method, $local_class, $local_moniker, $local_cols,
+        $remote_class, $remote_moniker, $remote_cols, $extra) = @_;
+
+    my $info = {
+        %{$extra || {}},
+        name           => $relname,
+        type           => $method,
+        local_class    => $local_class,
+        local_moniker  => $local_moniker,
+        local_columns  => $local_cols,
+        remote_class   => $remote_class,
+        remote_moniker => $remote_moniker,
+        remote_columns => $remote_cols,
+    };
+
+    my $new_name = $relname;
+
+    my $map = $self->rel_name_map;
+    my $mapped = 0;
+
+    if ('HASH' eq ref($map)) {
+        my $name = $info->{name};
+        my $moniker = $info->{local_moniker};
+        if ($map->{$moniker} and 'HASH' eq ref($map->{$moniker})
+            and $map->{$moniker}{$name}
+        ) {
+            $new_name = $map->{$moniker}{$name};
+            $mapped   = 1;
+        }
+        elsif ($map->{$name} and not 'HASH' eq ref($map->{$name})) {
+            $new_name = $map->{$name};
+            $mapped   = 1;
+        }
+    }
+    elsif ('CODE' eq ref($map)) {
+        my $name = $map->($info);
+        if ($name) {
+            $new_name = $name;
+            $mapped   = 1;
+        }
+    }
+
+    return ($new_name, $mapped);
 }
 
 sub _cleanup {