Add Scala Native support

Modelled after [toml-scala](https://github.com/sparsetech/toml-scala).

Closes #20.

.travis.yml

@@ -1,8 +1,29 @@
-language: scala
-scala:
-  - 2.11.12
-  - 2.12.8
+language: java
+env:
+  - TRAVIS_SCALA_VERSION=2.11.11
+  - TRAVIS_SCALA_VERSION=2.12.8
 jdk:
   - oraclejdk8
+
+dist: trusty
+sudo: required
+
+addons:
+  apt:
+    update: true
+
+# Cache directory to S3 at the end of the build
+cache:
+  directories:
+    - $HOME/.cache/coursier
+
+# From https://raw.githubusercontent.com/scalalandio/chimney/master/.travis.yml
+before_script:
+  - if [[ "$TRAVIS_SCALA_VERSION" == 2.11.* ]]; then curl https://raw.githubusercontent.com/scala-native/scala-native/master/scripts/travis_setup.sh | bash -x; fi
+
 script:
-  sbt ++$TRAVIS_SCALA_VERSION trailJS/test trailJVM/test
+  - set -x &&
+    if [[ "$TRAVIS_SCALA_VERSION" == 2.11.* ]]; then testNative=trailNative/test; else testNative=""; fi &&
+    curl -o csbt https://raw.githubusercontent.com/coursier/sbt-launcher/master/csbt &&
+    chmod +x csbt &&
+    ./csbt --add-coursier=true ++$TRAVIS_SCALA_VERSION trailJVM/test trailJS/test $testNative

README.md

@@ -3,7 +3,7 @@
 [![Join the chat at https://gitter.im/sparsetech/trail](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/sparsetech/trail?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 [![Maven Central](https://img.shields.io/maven-central/v/tech.sparse/trail_2.12.svg)](http://search.maven.org/#search%7Cga%7C1%7Cg%3A%22tech.sparse%22%20AND%20a%3A%22trail_2.12%22)
 
-Trail is a routing library for Scala and Scala.js.
+Trail is a routing library for Scala. It is available for the JVM, Scala.js and Scala Native.
 
 ## Example
 ```scala

build.sbt

@@ -5,17 +5,20 @@ val Leaf       = "0.1.0"
 val Scala2_11  = "2.11.12"
 val Scala2_12  = "2.12.8"
 val ScalaTest  = "3.0.5"
+val ScalaTestNative = "3.2.0-SNAP10"
 
 val SharedSettings = Seq(
-  name := "trail",
+  name         := "trail",
   organization := "tech.sparse",
-  scalaVersion := Scala2_12,
+
+  scalaVersion       := Scala2_12,
   crossScalaVersions := Seq(Scala2_12, Scala2_11),
-  scalacOptions := Seq(
+  scalacOptions      := Seq(
     "-unchecked",
     "-deprecation",
     "-encoding", "utf8"
   ),
+
   pomExtra :=
     <url>https://github.com/sparsetech/trail</url>
     <licenses>
@@ -36,20 +39,30 @@ val SharedSettings = Seq(
     </developers>
 )
 
-lazy val trail = crossProject(JSPlatform, JVMPlatform)
-  .crossType(CrossType.Full)
+lazy val root = project.in(file("."))
+  .aggregate(trail.js, trail.jvm, trail.native)
+  .settings(SharedSettings: _*)
+  .settings(skip in publish := true)
+
+lazy val trail = crossProject(JSPlatform, JVMPlatform, NativePlatform)
   .in(file("."))
   .settings(SharedSettings: _*)
   .settings(
     autoAPIMappings := true,
     apiMappings += (scalaInstance.value.libraryJar -> url(s"http://www.scala-lang.org/api/${scalaVersion.value}/")),
-    libraryDependencies ++= Seq(
-      "org.scalatest" %%% "scalatest" % ScalaTest % "test"
-    )
   )
   .jsSettings(
-    /* Use io.js for faster compilation of test cases */
-    scalaJSStage in Global := FastOptStage
+    libraryDependencies += "org.scalatest" %%% "scalatest" % ScalaTest % "test"
+  )
+  .jvmSettings(
+    libraryDependencies += "org.scalatest" %%% "scalatest" % ScalaTest % "test"
+  ).nativeSettings(
+    scalaVersion       := Scala2_11,
+    crossScalaVersions := Seq(Scala2_11),
+    // See https://github.com/scalalandio/chimney/issues/78#issuecomment-419705142
+    nativeLinkStubs    := true,
+    libraryDependencies +=
+      "org.scalatest" %%% "scalatest" % ScalaTestNative % "test"
   )
 
 lazy val manual = project.in(file("manual"))

manual/introduction.md

@@ -1,12 +1,12 @@
 # Introduction
-Trail is a routing library for Scala and Scala.js. It allows to define type-safe routes, generate URLs and perform pattern matching.
+Trail is a routing library for Scala. It allows to define type-safe routes, generate URLs and perform pattern matching.
 
 ## Installation
 Add the following dependencies to your build configuration:
 
 ```scala
 libraryDependencies += "tech.sparse" %%  "trail" % "%version%"  // Scala
-libraryDependencies += "tech.sparse" %%% "trail" % "%version%"  // Scala.js
+libraryDependencies += "tech.sparse" %%% "trail" % "%version%"  // Scala.js, Scala Native
 ```
 
 ## Example

native/src/main/scala/trail/URI.scala

@@ -0,0 +1,48 @@
+package trail
+
+import java.net.URLEncoder
+import java.io.ByteArrayOutputStream
+
+object URI {
+  /** @see http://stackoverflow.com/questions/607176/ */
+  def encode(s: String): String =
+    URLEncoder.encode(s, "UTF-8")
+      .replaceAll("\\+", "%20")
+      .replaceAll("\\%21", "!")
+      .replaceAll("\\%27", "'")
+      .replaceAll("\\%28", "(")
+      .replaceAll("\\%29", ")")
+      .replaceAll("\\%7E", "~")
+
+  /** Taken from https://android.googlesource.com/platform/libcore/+/adc854b798c1cfe3bfd4c27d68d5cee38ca617da/luni/src/main/java/java/net/URLDecoder.java */
+  def decode(s: String): String = {
+    val result = new StringBuffer(s.length)
+    val out = new ByteArrayOutputStream
+    var i = 0
+
+    while (i < s.length) {
+      val c = s.charAt(i)
+      if (c == '+') result.append(' ')
+      else if (c == '%') {
+        out.reset()
+        do {
+          if (i + 2 >= s.length)
+            throw new IllegalArgumentException("Incomplete % sequence at: " + i)
+          val d1 = Character.digit(s.charAt(i + 1), 16)
+          val d2 = Character.digit(s.charAt(i + 2), 16)
+          if (d1 == -1 || d2 == -1)
+            throw new IllegalArgumentException(
+              s"Invalid % sequence (${s.substring(i, i + 3)}) at: ${String.valueOf(i)}.")
+          out.write(((d1 << 4) + d2).toByte)
+          i += 3
+        } while (i < s.length && s.charAt(i) == '%')
+        result.append(out.toString("UTF-8"))
+      } else {
+        result.append(c)
+        i += 1
+      }
+    }
+
+    result.toString
+  }
+}

project/build.properties

@@ -1 +1 @@
-sbt.version=1.2.6
+sbt.version=1.2.8

project/plugins.sbt

@@ -1,4 +1,6 @@
 logLevel := Level.Warn
 
-addSbtPlugin("org.portable-scala" % "sbt-scalajs-crossproject" % "0.6.0")
-addSbtPlugin("org.scala-js"       % "sbt-scalajs"              % "0.6.26")
+addSbtPlugin("org.portable-scala" % "sbt-scalajs-crossproject"      % "0.6.0")
+addSbtPlugin("org.portable-scala" % "sbt-scala-native-crossproject" % "0.6.0")
+addSbtPlugin("org.scala-js"       % "sbt-scalajs"                   % "0.6.26")
+addSbtPlugin("org.scala-native"   % "sbt-scala-native"              % "0.3.8")