Merge pull request #342 from RafalSumislawski/scala_2_13

Upgrade to scala 2.13 and http4s 0.21.0 (second attempt)

Author: zarthross

Diff for: .travis.yml

@@ -1,7 +1,7 @@
 language: scala
 scala:
-- 2.11.12
-- 2.12.8
+- 2.12.10
+- 2.13.1
 jdk:
 - openjdk8
 - openjdk11

Diff for: build.sbt

@@ -16,19 +16,31 @@ lazy val rho = project
 
 lazy val `rho-core` = project
   .in(file("core"))
-  .settings(rhoPreviousArtifacts(lastVersion = "0.19.0", "core"))
-  .settings(buildSettings: _*)
+  .settings(mimaConfiguration)
+  .settings(buildSettings ++ Seq(
+    Compile / unmanagedSourceDirectories ++= {
+      val baseDir = baseDirectory.value
+
+      val mainSrcDir = "src/main/scala"
+      CrossVersion.partialVersion(scalaVersion.value) match {
+        case Some((2, minor)) if minor <= 12 => Seq(baseDir / s"$mainSrcDir-2.12-")
+        case Some((2, minor)) if minor >= 13 => Seq(baseDir / s"$mainSrcDir-2.13+")
+        case _ => Nil
+      }
+    },
+    libraryDependencies ++= Seq("org.scala-lang.modules" %% "scala-collection-compat" % "2.0.0")
+  ): _*)
 
 lazy val `rho-hal` = project
   .in(file("hal"))
   .settings(buildSettings :+ halDeps: _*)
-  .settings(rhoPreviousArtifacts(lastVersion = "0.19.0", "hal"))
+  .settings(mimaConfiguration)
   .dependsOn(`rho-core`)
 
 lazy val `rho-swagger` = project
   .in(file("swagger"))
   .settings(buildSettings :+ swaggerDeps: _*)
-  .settings(rhoPreviousArtifacts(lastVersion = "0.19.0", "swagger"))
+  .settings(mimaConfiguration)
   .dependsOn(`rho-core` % "compile->compile;test->test")
 
 lazy val docs = project
@@ -46,7 +58,7 @@ lazy val docs = project
       version.value,
       apiVersion.value
     ),
-    scalacOptions in (ScalaUnidoc, unidoc) += "-Ypartial-unification",
+    scalacOptions in (ScalaUnidoc, unidoc) ++= versionSpecificEnabledFlags(scalaVersion.value),
     unidocProjectFilter in (ScalaUnidoc, unidoc) := inProjects(
       `rho-core`,
       `rho-hal`,
@@ -77,18 +89,22 @@ lazy val `rho-examples` = project
       ): _*)
   .dependsOn(`rho-swagger`, `rho-hal`)
 
-lazy val compileFlags = Seq(
+lazy val compilerFlags = Seq(
   "-feature",
   "-deprecation",
   "-unchecked",
   "-language:higherKinds",
   "-language:existentials",
   "-language:implicitConversions",
   "-Ywarn-unused",
-  "-Ypartial-unification",
   "-Xfatal-warnings"
 )
 
+def versionSpecificEnabledFlags(version: String) = (CrossVersion.partialVersion(version) match {
+  case Some((2, 13)) => Seq.empty[String]
+  case _ => Seq("-Ypartial-unification")
+})
+
 /* Don't publish setting */
 lazy val dontPublish = packagedArtifacts := Map.empty
 
@@ -99,9 +115,9 @@ lazy val license = licenses in ThisBuild := Seq(
 
 lazy val buildSettings = publishing ++
   Seq(
-    scalaVersion := "2.12.8",
-    crossScalaVersions := Seq(scalaVersion.value, "2.11.12"),
-    scalacOptions ++= compileFlags,
+    scalaVersion := "2.13.1",
+    crossScalaVersions := Seq(scalaVersion.value, "2.12.10"),
+    scalacOptions := compilerFlags ++ versionSpecificEnabledFlags(scalaVersion.value),
     resolvers += Resolver.sonatypeRepo("snapshots"),
     fork in run := true,
     organization in ThisBuild := "org.http4s",

Diff for: core/src/main/scala-2.12-/jdk/CollectionConverters.scala

@@ -0,0 +1,5 @@
+package scala.jdk
+
+import scala.collection.convert.{DecorateAsJava, DecorateAsScala}
+
+object CollectionConverters extends DecorateAsJava with DecorateAsScala

Diff for: core/src/main/scala-2.12-/scala/collection/compat/view/MapViewExtensionMethods.scala

@@ -0,0 +1,13 @@
+package scala.collection.compat.view
+
+import scala.collection.generic.CanBuildFrom
+
+class MapViewExtensionMethods[K, V, C <: scala.collection.Map[K, V]](private val self: IterableView[(K, V), C]) extends AnyVal {
+  def mapValues[W, That](f: V => W)(implicit bf: CanBuildFrom[IterableView[(K, V), C], (K, W), That]): That =
+    self.map[(K, W), That] { case (k, v) => (k, f(v)) }
+}
+
+trait MapViewExtensions {
+  implicit def toMapViewExtensionMethods[K, V, C <: scala.collection.Map[K, V]](self: IterableView[(K, V), C]): MapViewExtensionMethods[K, V, C] =
+    new MapViewExtensionMethods[K, V, C](self)
+}

Diff for: core/src/main/scala-2.12-/scala/collection/compat/view/package.scala

@@ -0,0 +1,7 @@
+package scala.collection.compat
+
+import scala.collection.{IterableView => SCIterableView}
+
+package object view extends MapViewExtensions {
+  type IterableView[A, B] = SCIterableView[A, B]
+}

Diff for: core/src/main/scala-2.13+/scala/collection/compat/view/package.scala

@@ -0,0 +1,7 @@
+package scala.collection.compat
+
+import scala.collection.{IterableOps, View}
+
+package object view {
+  type IterableView[A, _] = IterableOps[A, View, View[A]]
+}

Diff for: core/src/main/scala/org/http4s/rho/CompileRoutes.scala

@@ -2,11 +2,8 @@ package org.http4s
 package rho
 
 import scala.collection.immutable.Seq
-
-import cats.Monad
-import cats.data.Kleisli
+import cats.effect.Sync
 import shapeless.HList
-
 import org.http4s.rho.RhoRoute.Tpe
 import org.http4s.rho.bits.PathTree
 
@@ -43,8 +40,8 @@ object CompileRoutes {
     * @param routes `Seq` of routes to bundle into a service.
     * @return An `HttpRoutes`
     */
-  def foldRoutes[F[_]: Monad](routes: Seq[RhoRoute.Tpe[F]]): HttpRoutes[F] = {
+  def foldRoutes[F[_]: Sync](routes: Seq[RhoRoute.Tpe[F]]): HttpRoutes[F] = {
     val tree = routes.foldLeft(PathTree[F]()){ (t, r) => t.appendRoute(r) }
-    Kleisli((req: Request[F]) => tree.getResult(req).toResponse)
+    HttpRoutes((req: Request[F]) => tree.getResult(req).toResponse)
   }
 }

Diff for: core/src/main/scala/org/http4s/rho/RhoDslPathExtractors.scala

@@ -2,19 +2,27 @@ package org.http4s.rho
 
 import org.http4s.rho.bits.PathAST._
 import org.http4s.rho.bits._
+import org.http4s.rho.RhoDslPathExtractors._
 import shapeless.{::, HNil}
 
 import scala.reflect.runtime.universe.TypeTag
 
 trait RhoDslPathExtractors[F[_]] {
 
-  private val stringTag = implicitly[TypeTag[String]]
-
   implicit def pathMatch(s: String): TypedPath[F, HNil] = TypedPath(PathMatch(s))
 
-  implicit def pathMatch(s: Symbol): TypedPath[F, String :: HNil] =
+  /**
+    * Provides 'pathVar syntax for String path variables (Scala 2.12 only)
+    */
+  implicit def pathCapture(s: Symbol): TypedPath[F, String :: HNil] =
     TypedPath(PathCapture(s.name, None, StringParser.strParser, stringTag))
 
+  /**
+    * Provides pv"pathVarName" syntax for String path variables as an alternative for 'pathVar (Symbol) syntax which was removed in Scala 2.13.
+    */
+  implicit def pathCapture(sc: StringContext): PathCaptureStringContext[F] =
+    new PathCaptureStringContext[F](sc)
+
   /**
     * Defines a path variable of a URI that should be bound to a route definition
     */
@@ -34,3 +42,13 @@ trait RhoDslPathExtractors[F[_]] {
     TypedPath(PathCapture[F](id, Some(description), parser, stringTag))
 
 }
+
+object RhoDslPathExtractors {
+
+  private val stringTag = implicitly[TypeTag[String]]
+
+  class PathCaptureStringContext[F[_]](val sc: StringContext) extends AnyVal {
+    def pv(): TypedPath[F, String :: HNil] =
+      TypedPath[F, String :: HNil](PathCapture(sc.parts.mkString, None, StringParser.strParser, stringTag))
+  }
+}

Diff for: core/src/main/scala/org/http4s/rho/RhoRoutes.scala

@@ -2,8 +2,7 @@ package org.http4s
 package rho
 
 import scala.collection.immutable.Seq
-
-import cats.Monad
+import cats.effect.Sync
 import org.http4s.rho.bits.PathAST.TypedPath
 import org.log4s.getLogger
 import shapeless.{HList, HNil}
@@ -24,7 +23,7 @@ import shapeless.{HList, HNil}
   *
   * @param routes Routes to prepend before elements in the constructor.
   */
-class RhoRoutes[F[_]: Monad](routes: Seq[RhoRoute[F, _ <: HList]] = Vector.empty)
+class RhoRoutes[F[_]: Sync](routes: Seq[RhoRoute[F, _ <: HList]] = Vector.empty)
     extends bits.MethodAliases
     with bits.ResponseGeneratorInstances[F]
     with RoutePrependable[F, RhoRoutes[F]]

Diff for: core/src/main/scala/org/http4s/rho/RoutesBuilder.scala

@@ -2,12 +2,14 @@ package org.http4s.rho
 
 import scala.collection.immutable.VectorBuilder
 import scala.collection.immutable.Seq
-import cats.Monad
+import cats.effect.Sync
 import shapeless.HList
 import org.http4s._
 
+import scala.collection.compat._
+
 /** CompileRoutes which accumulates routes and can build a `HttpRoutes` */
-final class RoutesBuilder[F[_]: Monad] private(internalRoutes: VectorBuilder[RhoRoute.Tpe[F]]) extends CompileRoutes[F, RhoRoute.Tpe[F]] {
+final class RoutesBuilder[F[_]: Sync] private(internalRoutes: VectorBuilder[RhoRoute.Tpe[F]]) extends CompileRoutes[F, RhoRoute.Tpe[F]] {
 
   /** Turn the accumulated routes into an `HttpRoutes`
     *
@@ -25,8 +27,8 @@ final class RoutesBuilder[F[_]: Monad] private(internalRoutes: VectorBuilder[Rho
     * @param routes Routes to accumulate.
     * @return `this` instance with its internal state mutated.
     */
-  def append(routes: TraversableOnce[RhoRoute.Tpe[F]]): this.type = {
-    internalRoutes ++= routes
+  def append(routes: IterableOnce[RhoRoute.Tpe[F]]): this.type = {
+    internalRoutes ++= routes.iterator.to(Iterable)
     this
   }
 
@@ -46,10 +48,10 @@ final class RoutesBuilder[F[_]: Monad] private(internalRoutes: VectorBuilder[Rho
 
 object RoutesBuilder {
   /** Constructor method for new `RoutesBuilder` instances */
-  def apply[F[_]: Monad](): RoutesBuilder[F] = apply(Seq.empty)
+  def apply[F[_]: Sync](): RoutesBuilder[F] = apply(Seq.empty)
 
   /** Constructor method for new `RoutesBuilder` instances with existing routes */
-  def apply[F[_]: Monad](routes: Seq[RhoRoute.Tpe[F]]): RoutesBuilder[F] = {
+  def apply[F[_]: Sync](routes: Seq[RhoRoute.Tpe[F]]): RoutesBuilder[F] = {
     val builder = new VectorBuilder[RhoRoute.Tpe[F]]
     builder ++= routes
 

Diff for: core/src/main/scala/org/http4s/rho/bits/HeaderAppendable.scala

@@ -1,8 +1,6 @@
 package org.http4s
 package rho.bits
 
-import scala.language.higherKinds
-
 import shapeless.HList
 import shapeless.ops.hlist.Prepend
 

Diff for: core/src/main/scala/org/http4s/rho/bits/PathTree.scala

@@ -258,12 +258,12 @@ private[rho] trait PathTreeOps[F[_]] extends RuleExecutor[F] {
 
             if (!result.isEmpty || end.isEmpty || method == Method.OPTIONS) result
             else FailureResponse.pure[F] {
-              val ms = end.keys
+              val ms = end.keySet
               val allowedMethods = ms.mkString(", ")
               val msg = s"$method not allowed. Defined methods: $allowedMethods\n"
 
               F.map(MethodNotAllowed.pure(msg))(
-                _.putHeaders(headers.Allow(ms.head, ms.tail.toList:_*)))
+                _.putHeaders(headers.Allow(ms)))
             }
         }
       }

Diff for: core/src/main/scala/org/http4s/rho/bits/QueryParser.scala

@@ -6,7 +6,7 @@ import org.http4s.rho.bits.QueryParser.Params
 
 import scala.annotation.tailrec
 import scala.collection.immutable.Seq
-import scala.collection.generic.CanBuildFrom
+import scala.collection.compat._
 
 /** Extract a value from the `Request` `Query`
   *
@@ -41,9 +41,9 @@ trait QueryParsers[F[_]] extends FailureResponseOps[F] {
     *
     * The elements must have the same name and each be a valid representation of the requisite type.
     */
-  implicit def multipleParse[A, B[_]](implicit F: Monad[F], p: StringParser[F, A], cbf: CanBuildFrom[Seq[_], A, B[A]]) = new QueryParser[F, B[A]] {
+  implicit def multipleParse[A, B[_]](implicit F: Monad[F], p: StringParser[F, A], cbf: Factory[A, B[A]]) = new QueryParser[F, B[A]] {
     override def collect(name: String, params: Params, default: Option[B[A]]): ResultResponse[F, B[A]] = {
-      val b = cbf()
+      val b = cbf.newBuilder
       params.get(name) match {
         case None => SuccessResponse(default.getOrElse(b.result))
         case Some(Seq()) => SuccessResponse(default.getOrElse(b.result))

Diff for: core/src/main/scala/org/http4s/rho/package.scala

@@ -6,8 +6,6 @@ import org.http4s.rho.bits._
 import org.http4s.rho.bits.PathAST._
 import shapeless.{HList, HNil}
 
-import scala.language.implicitConversions
-
 package object rho extends org.http4s.syntax.AllSyntax {
   type RhoMiddleware[F[_]] = Seq[RhoRoute[F, _ <: HList]] => Seq[RhoRoute[F, _ <: HList]]
 

Diff for: core/src/test/scala/ApiExamples.scala

@@ -39,8 +39,8 @@ class ApiExamples extends Specification {
         GET / "helloworldnumber" / pathVar[Int] / "foo" |>> { i: Int =>
           Ok(s"Received $i")
         }
-        // the symbol 'world just says 'capture a String' with variable name "world"
-        GET / "helloworldstring" / 'world / "foo" |>> { i: String =>
+        // the pv"world" (pv stands for path variable) says 'capture a String' with variable name "world"
+        GET / "helloworldstring" / pv"world" / "foo" |>> { i: String =>
           Ok(s"Received $i")
         }
         // capture dates
@@ -118,7 +118,7 @@ class ApiExamples extends Specification {
         val path2 = "two" / pathVar[Int]
 
         val getLength = captureMap(`Content-Length`)(_.length)
-        val getTag = captureMap(ETag)(_ => -1l)
+        val getTag = captureMap(ETag)(_ => -1L)
 
         GET / (path1 || path2) +? param[String]("foo") >>> (getLength || getTag) |>> {
           (i: Int, foo: String, v: Long) => Ok(s"Received $i, $foo, $v")
@@ -134,7 +134,7 @@ class ApiExamples extends Specification {
         GET / "request" |>> { _: Request[IO] =>
           Ok("I don't actually need a request...")
         }
-        GET / "request" / 'foo |>> { (_: Request[IO], _: String) =>
+        GET / "request" / pv"foo" |>> { (_: Request[IO], _: String) =>
           Ok("I wanted a request")
         }
       }