Force rendering package object when a validated newtype is present (#1656)

Author: kubukoz

CHANGELOG.md

@@ -8,6 +8,8 @@ Thank you!
 # 0.18.30
 
 * Add utilities for Service.Builder in [#1644](https://github.com/disneystreaming/smithy4s/pull/1644)
+* Use correct cross path for protobuf-runtime-scala in [#1648](https://github.com/disneystreaming/smithy4s/pull/1648)
+* Force rendering package object when a validated newtype is present in [#1656](https://github.com/disneystreaming/smithy4s/pull/1656)
 
 # 0.18.29
 

modules/codegen/src/smithy4s/codegen/internals/Renderer.scala

@@ -81,15 +81,17 @@ private[internals] object Renderer {
   def apply(unit: CompilationUnit): List[Result] = {
     val r = new Renderer(unit)
 
-    val pack = Result(
-      unit.namespace,
-      "package",
-      r.renderPackageContents.list
-        .map(_.segments.toList.map(_.show).mkString)
-        .mkString(
-          System.lineSeparator()
-        )
-    )
+    val packageObjectFile = r.renderPackageContents.map { packageLines =>
+      Result(
+        unit.namespace,
+        "package",
+        packageLines.list
+          .map(_.segments.toList.map(_.show).mkString)
+          .mkString(
+            System.lineSeparator()
+          )
+      )
+    }
 
     val classes = unit.declarations.map { decl =>
       val renderResult = r.renderDecl(decl) ++ newline
@@ -161,13 +163,7 @@ private[internals] object Renderer {
       Result(unit.namespace, decl.name, content)
     }
 
-    val packageApplicableDecls = unit.declarations.filter {
-      case _: TypeAlias | _: Service => true
-      case _                         => false
-    }
-
-    if (packageApplicableDecls.isEmpty) classes
-    else pack :: classes
+    packageObjectFile.toList ::: classes
   }
 
 }
@@ -271,7 +267,7 @@ private[internals] class Renderer(compilationUnit: CompilationUnit) { self =>
       }
   }
 
-  def renderPackageContents: Lines = {
+  def renderPackageContents: Option[Lines] = {
     val typeAliases = compilationUnit.declarations
       .collect {
         case TypeAlias(_, name, _, _, _, hints) =>
@@ -288,24 +284,31 @@ private[internals] class Renderer(compilationUnit: CompilationUnit) { self =>
         )
       }
 
-    val blk =
-      block(
-        line"package object ${compilationUnit.namespace.split('.').last}"
-      )(
-        compilationUnit.declarations.map(renderDeclPackageContents),
-        newline,
-        typeAliases,
-        newline
-      )
+    val serviceAliases =
+      compilationUnit.declarations.map(renderDeclPackageContents)
 
-    val parts = compilationUnit.namespace.split('.').filter(_.nonEmpty)
-    if (parts.size > 1) {
-      lines(
-        line"package ${parts.dropRight(1).mkString(".")}",
-        newline,
-        blk
-      )
-    } else blk
+    val packageContents = lines(serviceAliases, newline, typeAliases, newline)
+
+    packageContents.some
+      .filterNot(_.isBlank)
+      .map { contents =>
+        block(
+          line"package object ${compilationUnit.namespace.split('.').last}"
+        )(
+          contents
+        )
+      }
+      .map { blk =>
+        val parts = compilationUnit.namespace.split('.').filter(_.nonEmpty)
+
+        if (parts.size > 1) {
+          lines(
+            line"package ${parts.dropRight(1).mkString(".")}",
+            newline,
+            blk
+          )
+        } else blk
+      }
   }
 
   private def renderDeclPackageContents(decl: Decl): Lines = decl match {

modules/codegen/src/smithy4s/codegen/internals/ToLine.scala

@@ -23,6 +23,7 @@ import cats.kernel.Monoid
 import java.util.UUID
 
 import LineSegment._
+import cats.kernel.Eq
 
 private[internals] trait ToLine[A] {
   def render(a: A): Line
@@ -168,5 +169,6 @@ private[internals] object Line {
   val space: Line = Line(" ")
   val dot: Line = Line(".")
   implicit val monoid: Monoid[Line] = Monoid.instance(empty, _ + _)
+  implicit val eq: Eq[Line] = Eq.fromUniversalEquals
 
 }

modules/codegen/src/smithy4s/codegen/internals/ToLines.scala

@@ -58,6 +58,7 @@ private[internals] object ToLines {
 
 private[internals] case class Lines(list: List[Line]) {
   def isEmpty: Boolean = list.isEmpty
+  def isBlank: Boolean = list.forall(_.isEmpty)
 
   def block(l: LinesWithValue*): Lines = {
     val openBlock: List[Line] =

modules/codegen/test/src/smithy4s/codegen/internals/RendererSpec.scala

@@ -686,4 +686,27 @@ final class RendererSpec extends munit.ScalaCheckSuite {
       )
     )
   }
+
+  // regression test for https://github.com/disneystreaming/smithy4s/issues/1655
+  test("validated newtypes force creation of a package object") {
+    val smithy =
+      """$version: "2"
+        |
+        |namespace smithy4s.example
+        |
+        |use smithy4s.meta#validateNewtype
+        |
+        |@validateNewtype
+        |@length(min: 1)
+        |string SomeValidatedNewtype
+        |""".stripMargin
+
+    val files = generateScalaCode(smithy).keySet
+
+    assert(
+      files.contains("smithy4s.example.package"),
+      files.toString + " should contain smithy4s.example.package"
+    )
+
+  }
 }