Add support for Dotty projects (#397)

* Abstract over the scala compiler organization

* Support using a locally published compiler

Publishing locally with sbt means publishing ivy-style, which uses
a different naming convention than maven, we now handle both cases.

* Add minimal support for Dotty projects

* Rewrite scalalib.Dep, introduce scalalib.CrossVersion

Instead of Dep being a trait with three cases (Java/Scala/Point), it is
now a case class where the cross field is an instance of the
CrossVersion trait which has three cases (Constant/Binary/Full). This is
more versatile since it allows for non-empty constant suffixes which
will be used to implement withDottyCompat in the next commit. It's
also a cleaner separation of concerns. We also deduplicate various
pieces of codes that computed the artifact name: this is now always handled in
Dep and CrossVersion.

* Add simple way to use Scala 2 deps in a Dotty project

This is similar to the withDottyCompat method in the sbt-dotty plugin.

* Turn off the Dotty test on Java >= 9

1 files changed, 21 insertions, 5 deletions

diff --git a/scalalib/test/src/mill/scalalib/HelloWorldTests.scala b/scalalib/test/src/mill/scalalib/HelloWorldTests.scala
index 7a1dd6df..1a89a0e3 100644
--- a/scalalib/test/src/mill/scalalib/HelloWorldTests.scala
+++ b/scalalib/test/src/mill/scalalib/HelloWorldTests.scala
@@ -14,6 +14,7 @@ import utest._
 import utest.framework.TestPath
 
 import scala.collection.JavaConverters._
+import scala.util.Properties.isJavaAtLeast
 
 
 object HelloWorldTests extends TestSuite {
@@ -190,11 +191,7 @@ object HelloWorldTests extends TestSuite {
   object HelloWorldTypeLevel extends HelloBase{
     object foo extends ScalaModule {
       def scalaVersion = "2.11.8"
-      override def mapDependencies = T.task{ d: coursier.Dependency =>
-        val artifacts = Set("scala-library", "scala-compiler", "scala-reflect")
-        if (d.module.organization != "org.scala-lang" || !artifacts(d.module.name)) d
-        else d.copy(module = d.module.copy(organization = "org.typelevel"))
-      }
+      override def scalaOrganization = "org.typelevel"
 
       def ivyDeps = Agg(
         ivy"com.github.julien-truffaut::monocle-macro::1.4.0"
@@ -238,6 +235,13 @@ object HelloWorldTests extends TestSuite {
     }
   }
 
+  object HelloDotty extends HelloBase{
+    object foo extends ScalaModule {
+      def scalaVersion = "0.9.0-RC1"
+      def ivyDeps = Agg(ivy"org.typelevel::cats-core:1.2.0".withDottyCompat(scalaVersion()))
+     }
+  }
+
   val resourcePath = pwd / 'scalalib / 'test / 'resources / "hello-world"
 
   def jarMainClass(jar: JarFile): Option[String] = {
@@ -815,5 +819,17 @@ object HelloWorldTests extends TestSuite {
       )
     }
 
+    'dotty - workspaceTest(
+      HelloDotty,
+      resourcePath = pwd / 'scalalib / 'test / 'resources / "hello-dotty"
+    ){ eval =>
+      if (isJavaAtLeast("9")) {
+        // Skip the test because Dotty does not support Java >= 9 yet
+        // (see https://github.com/lampepfl/dotty/pull/3138)
+      } else {
+        val Right((_, evalCount)) = eval.apply(HelloDotty.foo.run())
+        assert(evalCount > 0)
+      }
+    }
   }
 }