Ensure placeholders and parameters are processed in a consistent order

relate/src/main/scala/com/lucidchart/relate/Parameters.scala

@@ -632,14 +632,17 @@ trait MultipleParameter extends Parameter {
   }
 }
 
-class TupleParameter(val params: Iterable[SingleParameter]) extends MultipleParameter {
+class TupleParameter(_params: Iterable[SingleParameter]) extends MultipleParameter {
+  // get a `Seq` to make sure placeholder and parameterize get the same ordering
+  override protected val params = _params.toSeq
   def placeholder = params.iterator.map(_.placeholder).mkString(",")
 }
 
 object TupleParameter {
   def apply(params: SingleParameter*) = new TupleParameter(params)
 }
 
-class TuplesParameter(val params: Iterable[TupleParameter]) extends MultipleParameter {
+class TuplesParameter(_params: Iterable[TupleParameter]) extends MultipleParameter {
+  override protected val params = _params.toSeq
   def placeholder = if (params.isEmpty) "" else params.map(_.placeholder).mkString("(", "),(", ")")
 }

relate/src/test/scala/ParameterizationTest.scala

@@ -24,6 +24,23 @@ class ParameterizationTest extends Specification {
       val querySql = sql"SELECT * FROM myTable WHERE id IN ($hashSet)"
       querySql.toString mustEqual "SELECT * FROM myTable WHERE id IN (?,?,?)"
     }
+
+    "provide placeholders and parameters in the same order" in {
+      val setParams = scala.collection.mutable.Map.empty[Int, Int]
+      case class Param(int: Int) extends SingleParameter {
+        protected[this] def set(statement: PreparedStatement, i: Int) = setParams(i) = int
+        override def placeholder = int.toString
+      }
+
+      val paramsSet: Parameter = Set(Param(1), Param(2), Param(3))
+      paramsSet.parameterize(null, 1)
+      val query = sql"SELECT * FROM myTable WHERE id IN ($paramsSet)".toString
+
+      setParams must haveSize(3)
+      val order = setParams.toSeq.sortBy(_._1).map(_._2).mkString(",")
+      // the order of the "placeholders" should match the order of the parameters
+      query mustEqual s"SELECT * FROM myTable WHERE id IN ($order)"
+    }
   }
 
   "tuple paramater" should {