Tuple-based Tables.scala file generated by Codegen does not compile

[ludwiggj]

I'm playing with slick 2 and codegen, using MySql for the database. I started with the Coffee / Suppliers example from the hello slick activator template.

I'm trying to use codegen to create a new Tables.scala file from the Coffee and Suppliers database tables, which will allow the existing client code to work e.g.

db.withSession { implicit session =>
  ...
  suppliers += (101, "Acme, Inc.", "99 Market Street", "Groundsville", "CA", "95199")
  suppliers += ( 49, "Superior Coffee", "1 Party Place", "Mendocino", "CA", "95460")
  suppliers += (150, "The High Ground", "100 Coffee Lane", "Meadows", "CA", "93966")
  ...
}

I've been posting to the slick google group for help. I've had to use a custom generator to use tuples for the rows instead of case classes:

import scala.slick.driver.MySQLDriver
import scala.slick.driver.MySQLDriver.simple._
import scala.slick.codegen.SourceCodeGenerator
import scala.slick.model.Model

object SlickAutoGen {
  def main(args: Array[String]) {

    val db = Database.forConfig("db")

    val model = db.withSession { implicit session =>
        MySQLDriver.profile.createModel()
    }

    case class SourceGen(model: Model) extends SourceCodeGenerator(model) {
      override def Table = new Table(_) {
        override lazy val EntityType = new EntityType {
          override val classEnabled: Boolean = false
        }
      }
    }

    SourceGen(model).writeToFile(
      "scala.slick.driver.MySQLDriver", "src/main/scala", "org.ludwiggj.finance.database", "Tables", "Tables.scala")
  }
}

This generates the following code for Tables.scala (relevant parts shown only):

trait Tables {
  ...
  /** Row type of table Coffees */
  type CoffeesRow = (String, Int, Double, Int, Int)
  /** Constructor for CoffeesRow providing default values if available in the database schema. */
  def CoffeesRow(name: String, supId: Int, price: Double, sales: Int, total: Int): CoffeesRow = {
    (name, supId, price, sales, total)
  }
  /** GetResult implicit for fetching CoffeesRow objects using plain SQL queries */
  implicit def GetResultCoffeesRow(implicit e0: GR[String], e1: GR[Int], e2: GR[Double]): GR[CoffeesRow] = GR{
    prs => import prs._
    CoffeesRow.tupled((<<[String], <<[Int], <<[Double], <<[Int], <<[Int]))
  }
  /** Table description of table COFFEES. Objects of this class serve as prototypes for rows in queries. */
  class Coffees(_tableTag: Tag) extends Table[CoffeesRow](_tableTag, "COFFEES") {
    def * = (name, supId, price, sales, total) <> (CoffeesRow.tupled, CoffeesRow.unapply)
    /** Maps whole row to an option. Useful for outer joins. */
    def ? = (name.?, supId.?, price.?, sales.?, total.?).shaped.<>({r=>import r._; _1.map(_=>
        CoffeesRow.tupled((_1.get, _2.get, _3.get, _4.get, _5.get)))}, (_:Any) =>
        throw new Exception("Inserting into ? projection not supported."))   
    ...
  }
  ...
}

This results in the following compilation errors:

Error:(28, 5) missing arguments for method CoffeesRow in trait Tables;
follow this method with `_' if you want to treat it as a partially applied function
CoffeesRow.tupled((<<[String], <<[Int], <<[Double], <<[Int], <<[Int]))

Error:(32, 52) missing arguments for method CoffeesRow in trait Tables;
follow this method with `_' if you want to treat it as a partially applied function
def * = (name, supId, price, sales, total) <> (CoffeesRow.tupled, CoffeesRow.unapply)

Error:(32, 71) missing arguments for method CoffeesRow in trait Tables;
follow this method with `_' if you want to treat it as a partially applied function
def * = (name, supId, price, sales, total) <> (CoffeesRow.tupled, CoffeesRow.unapply)

Error:(34, 95) missing arguments for method CoffeesRow in trait Tables;
follow this method with `_' if you want to treat it as a partially applied function
def ? = (name.?, supId.?, price.?, sales.?, total.?).shaped.<>({r=>import r._; _1.map(_=> CoffeesRow.tupled((_1.get, _2.get, _3.get, _4.get, _5.get)))}, (_:Any) =>  throw new Exception("Inserting into ? projection not supported."))

I've been advised on the forum to raise this as a bug against CodeGenerator, and that I could disable the PlainSqlMapper as follows:

case class SourceGen(model: m.Model) extends SourceCodeGenerator(model) {
    override def Table = new Table(_) {
        override lazy val EntityType = new EntityType {
            override val classEnabled: Boolean = false
        }
        override lazy val PlainSqlMapper = new PlainSqlMapper{
            override val enabled = false
        }
    }
}

Disabling the PlainSqlMapper as above removes the first compilation error, but not those connected with the incorrect definitions of the * and ? methods, so it still won't compile.

I know I can fix this code by hand, but obviously codegen should produce the correctly compiling code!

(As an aside, I also wonder why the default behaviour of the code generator is to create Tables.scala with case classes; will this change in future to generate the tuples only version, so that the existing way of populating the database works with the schema classes generated by codegen?)