entc/gen: add edge-field api for schema and codegen (#1213)

examples/start/ent/car/car.go

@@ -15,10 +15,8 @@ const (
 	FieldModel = "model"
 	// FieldRegisteredAt holds the string denoting the registered_at field in the database.
 	FieldRegisteredAt = "registered_at"
-
 	// EdgeOwner holds the string denoting the owner edge name in mutations.
 	EdgeOwner = "owner"
-
 	// Table holds the table name of the car in the database.
 	Table = "cars"
 	// OwnerTable is the table the holds the owner relation/edge.
@@ -37,7 +35,8 @@ var Columns = []string{
 	FieldRegisteredAt,
 }
 
-// ForeignKeys holds the SQL foreign-keys that are owned by the Car type.
+// ForeignKeys holds the SQL foreign-keys that are owned by the "cars"
+// table and are not defined as standalone fields in the schema.
 var ForeignKeys = []string{
 	"user_cars",
 }

examples/start/ent/car_create.go

@@ -173,6 +173,7 @@ func (cc *CarCreate) createSpec() (*Car, *sqlgraph.CreateSpec) {
 		for _, k := range nodes {
 			edge.Target.Nodes = append(edge.Target.Nodes, k)
 		}
+		_node.user_cars = &nodes[0]
 		_spec.Edges = append(_spec.Edges, edge)
 	}
 	return _node, _spec

examples/start/ent/group/group.go

@@ -13,10 +13,8 @@ const (
 	FieldID = "id"
 	// FieldName holds the string denoting the name field in the database.
 	FieldName = "name"
-
 	// EdgeUsers holds the string denoting the users edge name in mutations.
 	EdgeUsers = "users"
-
 	// Table holds the table name of the group in the database.
 	Table = "groups"
 	// UsersTable is the table the holds the users relation/edge. The primary key declared below.

examples/start/ent/user/user.go

@@ -15,12 +15,10 @@ const (
 	FieldAge = "age"
 	// FieldName holds the string denoting the name field in the database.
 	FieldName = "name"
-
 	// EdgeCars holds the string denoting the cars edge name in mutations.
 	EdgeCars = "cars"
 	// EdgeGroups holds the string denoting the groups edge name in mutations.
 	EdgeGroups = "groups"
-
 	// Table holds the table name of the user in the database.
 	Table = "users"
 	// CarsTable is the table the holds the cars relation/edge.