First pass at implicitly propagating a `def basePath: Path` up the `Module` hierarchy, which each module receives and extends.

One constraint is that now must define your abstract modules as `trait`s rather than `class`es, or otherwise add an implicit `ctx: ModuleCtx` parameter to your class definition.

 So far this lets us remove some explicit `basePath` definitions in `build.sc`. Proper handling of `basePath` in `CrossModule`s is future work

2 files changed, 9 insertions, 11 deletions

diff --git a/scalalib/src/main/scala/mill/scalalib/Module.scala b/scalalib/src/main/scala/mill/scalalib/Module.scala
index c6fcfb4d..6cc47176 100644
--- a/scalalib/src/main/scala/mill/scalalib/Module.scala
+++ b/scalalib/src/main/scala/mill/scalalib/Module.scala
@@ -75,7 +75,6 @@ trait Module extends mill.Module with TaskModule { outer =>
   def compileIvyDeps = T{ Seq[Dep]() }
   def scalacPluginIvyDeps = T{ Seq[Dep]() }
   def runIvyDeps = T{ Seq[Dep]() }
-  def basePath: Path
 
   def scalacOptions = T{ Seq.empty[String] }
   def javacOptions = T{ Seq.empty[String] }
@@ -360,11 +359,10 @@ trait PublishModule extends Module { outer =>
 }
 
 trait SbtModule extends Module { outer =>
-  def basePath: Path
   override def sources = T.source{ basePath / 'src / 'main / 'scala }
   override def resources = T.source{ basePath / 'src / 'main / 'resources }
   trait Tests extends super.Tests{
-    def basePath = outer.basePath
+    override def basePath = outer.basePath
     override def sources = T.source{ basePath / 'src / 'test / 'scala }
     override def resources = T.source{ basePath / 'src / 'test / 'resources }
   }
diff --git a/scalalib/src/test/scala/mill/scalalib/HelloWorldTests.scala b/scalalib/src/test/scala/mill/scalalib/HelloWorldTests.scala
index 4cd1d58d..c9419d07 100644
--- a/scalalib/src/test/scala/mill/scalalib/HelloWorldTests.scala
+++ b/scalalib/src/test/scala/mill/scalalib/HelloWorldTests.scala
@@ -9,7 +9,7 @@ import mill.define.{Cross, Target}
 import mill.discover.Discovered
 import mill.eval.{Evaluator, Result}
 import mill.scalalib.publish._
-import mill.util.TestEvaluator
+import mill.util.{TestEvaluator, TestUtil}
 import sbt.internal.inc.CompileFailed
 import utest._
 
@@ -20,8 +20,8 @@ trait HelloWorldModule extends scalalib.Module {
   def basePath = HelloWorldTests.workingSrcPath
 }
 
-object HelloWorld extends HelloWorldModule
-object CrossHelloWorld extends mill.Module{
+object HelloWorld extends TestUtil.BaseModule with HelloWorldModule
+object CrossHelloWorld extends TestUtil.BaseModule {
   val cross =
     for(v <- Cross("2.10.6", "2.11.11", "2.12.3", "2.12.4"))
     yield new HelloWorldModule {
@@ -29,19 +29,19 @@ object CrossHelloWorld extends mill.Module{
     }
 }
 
-object HelloWorldWithMain extends HelloWorldModule {
+object HelloWorldWithMain extends TestUtil.BaseModule with HelloWorldModule {
   def mainClass = Some("Main")
 }
 
-object HelloWorldWarnUnused extends HelloWorldModule {
+object HelloWorldWarnUnused extends TestUtil.BaseModule with HelloWorldModule {
   def scalacOptions = T(Seq("-Ywarn-unused"))
 }
 
-object HelloWorldFatalWarnings extends HelloWorldModule {
+object HelloWorldFatalWarnings extends TestUtil.BaseModule with HelloWorldModule {
   def scalacOptions = T(Seq("-Ywarn-unused", "-Xfatal-warnings"))
 }
 
-object HelloWorldWithPublish extends HelloWorldModule with PublishModule {
+object HelloWorldWithPublish extends TestUtil.BaseModule with HelloWorldModule with PublishModule {
   def artifactName = "hello-world"
   def publishVersion = "0.0.1"
 
@@ -60,7 +60,7 @@ object HelloWorldWithPublish extends HelloWorldModule with PublishModule {
       Seq(Developer("lihaoyi", "Li Haoyi", "https://github.com/lihaoyi"))
   )
 }
-object HelloWorldScalaOverride extends HelloWorldModule {
+object HelloWorldScalaOverride extends TestUtil.BaseModule with HelloWorldModule {
   override def scalaVersion: Target[String] = "2.11.11"
 }
 object HelloWorldTests extends TestSuite {