Fix refined newtypes

CHANGELOG.md

@@ -7,6 +7,7 @@ Thank you!
 
 # 0.18.25
 
+* Fixes an issue in which refinements wouldn't work on custom simple shapes (newtypes) (see [#1595](https://github.com/disneystreaming/smithy4s/pull/1595))
 * Fixes a regression from 0.18.4 which incorrectly rendered default values for certain types (see [#1593](https://github.com/disneystreaming/smithy4s/pull/1593))
 * Fixes an issue in which union members targetting Unit would fail to compile when used as traits (see [#1600](https://github.com/disneystreaming/smithy4s/pull/1600)).
 * Make the `transform` method in generated `*Gen` algebras final. This should make it possible to derive e.g. `FunctorK` instances in cats-tagless automatically (see [#1588](https://github.com/disneystreaming/smithy4s/pull/1588)).

modules/bootstrapped/src/generated/smithy4s/example/HasConstrainedNewtype.scala

@@ -0,0 +1,22 @@
+package smithy4s.example
+
+import smithy4s.Hints
+import smithy4s.Schema
+import smithy4s.ShapeId
+import smithy4s.ShapeTag
+import smithy4s.schema.Schema.struct
+
+final case class HasConstrainedNewtype(s: CityId)
+
+object HasConstrainedNewtype extends ShapeTag.Companion[HasConstrainedNewtype] {
+  val id: ShapeId = ShapeId("smithy4s.example", "HasConstrainedNewtype")
+
+  val hints: Hints = Hints.empty
+
+  // constructor using the original order from the spec
+  private def make(s: CityId): HasConstrainedNewtype = HasConstrainedNewtype(s)
+
+  implicit val schema: Schema[HasConstrainedNewtype] = struct(
+    CityId.schema.validated(smithy.api.Length(min = Some(1L), max = None)).required[HasConstrainedNewtype]("s", _.s),
+  )(make).withId(id).addHints(hints)
+}

modules/bootstrapped/src/generated/smithy4s/example/HasConstrainedNewtypes.scala

@@ -0,0 +1,26 @@
+package smithy4s.example
+
+import smithy4s.Hints
+import smithy4s.Schema
+import smithy4s.ShapeId
+import smithy4s.ShapeTag
+import smithy4s.schema.Schema.struct
+
+final case class HasConstrainedNewtypes(a: BucketName, b: CityId, c: Option[ObjectSize] = None, d: Option[IndexedSeq[String]] = None, e: Option[PNG] = None)
+
+object HasConstrainedNewtypes extends ShapeTag.Companion[HasConstrainedNewtypes] {
+  val id: ShapeId = ShapeId("smithy4s.example", "HasConstrainedNewtypes")
+
+  val hints: Hints = Hints.empty
+
+  // constructor using the original order from the spec
+  private def make(a: BucketName, b: CityId, c: Option[ObjectSize], d: Option[IndexedSeq[String]], e: Option[PNG]): HasConstrainedNewtypes = HasConstrainedNewtypes(a, b, c, d, e)
+
+  implicit val schema: Schema[HasConstrainedNewtypes] = struct(
+    BucketName.schema.validated(smithy.api.Length(min = Some(1L), max = None)).required[HasConstrainedNewtypes]("a", _.a),
+    CityId.schema.validated(smithy.api.Length(min = Some(1L), max = None)).required[HasConstrainedNewtypes]("b", _.b),
+    ObjectSize.schema.validated(smithy.api.Range(min = Some(scala.math.BigDecimal(1.0)), max = None)).optional[HasConstrainedNewtypes]("c", _.c),
+    SomeIndexSeq.underlyingSchema.validated(smithy.api.Length(min = Some(1L), max = None)).optional[HasConstrainedNewtypes]("d", _.d),
+    PNG.schema.validated(smithy.api.Length(min = Some(1L), max = None)).optional[HasConstrainedNewtypes]("e", _.e),
+  )(make).withId(id).addHints(hints)
+}

modules/core/src/smithy4s/RefinementProvider.scala

@@ -202,9 +202,14 @@ private[smithy4s] trait LowPriorityImplicits {
       : RefinementProvider[Pattern, E, E] =
     new RefinementProvider.PatternConstraint[E](e => e.value)
 
-  implicit def isomorphismConstraint[C, A, A0](implicit
+  @deprecated("Use isomorphismConstraint2 instead", "0.18.25")
+  def isomorphismConstraint[C, A, A0](implicit
       constraintOnA: RefinementProvider.Simple[C, A],
       iso: Bijection[A, A0]
-  ): RefinementProvider[C, A0, A0] = constraintOnA.imapFull[A0, A0](iso, iso)
+  ): RefinementProvider[C, A0, A0] = isomorphismConstraint2
 
+  implicit def isomorphismConstraint2[C, A, A0](implicit
+      iso: Bijection[A, A0],
+      constraintOnA: RefinementProvider.Simple[C, A]
+  ): RefinementProvider[C, A0, A0] = constraintOnA.imapFull[A0, A0](iso, iso)
 }

sampleSpecs/memberConstraints.smithy

@@ -14,3 +14,23 @@ map ConstrainedMap {
     value: String
 }
 
+// Regression test for https://github.com/disneystreaming/smithy4s/issues/1594
+structure HasConstrainedNewtypes {
+    // string newtype
+    @length(min: 1)
+    @required
+    a: BucketName
+    // string newtype, double-constrained
+    @length(min: 1)
+    @required
+    b: CityId
+    // int newtype
+    @range(min: 1)
+    c: ObjectSize
+    // list newtype, oh wait these are just lists. Still.
+    @length(min: 1)
+    d: SomeIndexSeq
+    // blob newtype
+    @length(min: 1)
+    e: PNG
+}