- Rename `basePath` -> `millSourcePath`

- Make `T.worker`s not flush out their directories between instantiations

22 files changed, 119 insertions, 112 deletions

diff --git a/core/src/mill/define/Cross.scala b/core/src/mill/define/Cross.scala
index b51064be..aa730e0d 100644
--- a/core/src/mill/define/Cross.scala
+++ b/core/src/mill/define/Cross.scala
@@ -61,7 +61,7 @@ class Cross[T](cases: Any*)
       c,
       ctx.copy(
         segments = ctx.segments ++ Seq(ctx.segment),
-        basePath = ctx.basePath / relPath,
+        millSourcePath = ctx.millSourcePath / relPath,
         segment = Segment.Cross(crossValues)
       )
     )
diff --git a/core/src/mill/define/Ctx.scala b/core/src/mill/define/Ctx.scala
index 6d685521..ddbdca96 100644
--- a/core/src/mill/define/Ctx.scala
+++ b/core/src/mill/define/Ctx.scala
@@ -45,7 +45,7 @@ case class Segments(value: Segment*){
 case class Ctx(enclosing: String,
                lineNum: Int,
                segment: Segment,
-               basePath: Path,
+               millSourcePath: Path,
                segments: Segments,
                overrides: Int){
 }
diff --git a/core/src/mill/define/Module.scala b/core/src/mill/define/Module.scala
index 11a98d95..039011d8 100644
--- a/core/src/mill/define/Module.scala
+++ b/core/src/mill/define/Module.scala
@@ -24,8 +24,8 @@ class Module(implicit outerCtx0: mill.define.Ctx) extends mill.moduledefs.Cacher
 
   lazy val millModuleDirectChildren = millInternal.reflectNestedObjects[Module]
   def millOuterCtx = outerCtx0
-  def basePath: Path = millOuterCtx.basePath / millOuterCtx.segment.pathSegments
-  implicit def millModuleBasePath: BasePath = BasePath(basePath)
+  def millSourcePath: Path = millOuterCtx.millSourcePath / millOuterCtx.segment.pathSegments
+  implicit def millModuleBasePath: BasePath = BasePath(millSourcePath)
   implicit def millModuleSegments: Segments = {
     millOuterCtx.segments ++ Seq(millOuterCtx.segment)
   }
@@ -92,19 +92,19 @@ trait TaskModule extends Module {
 object BaseModule{
   case class Implicit(value: BaseModule)
 }
-class BaseModule(basePath0: Path)
+class BaseModule(millSourcePath0: Path)
                 (implicit millModuleEnclosing0: sourcecode.Enclosing,
                  millModuleLine0: sourcecode.Line,
                  millName0: sourcecode.Name)
   extends Module()(
-    mill.define.Ctx.make(implicitly, implicitly, implicitly, BasePath(basePath0), Segments(), Overrides(0))
+    mill.define.Ctx.make(implicitly, implicitly, implicitly, BasePath(millSourcePath0), Segments(), Overrides(0))
   ){
   // A BaseModule should provide an empty Segments list to it's children, since
   // it is the root of the module tree, and thus must not include it's own
   // sourcecode.Name as part of the list,
   override implicit def millModuleSegments: Segments = Segments()
-  override def basePath = millOuterCtx.basePath
-  override implicit def millModuleBasePath: BasePath = BasePath(basePath)
+  override def millSourcePath = millOuterCtx.millSourcePath
+  override implicit def millModuleBasePath: BasePath = BasePath(millSourcePath)
   implicit def millImplicitBaseModule: BaseModule.Implicit = BaseModule.Implicit(this)
 }
 
diff --git a/core/src/mill/define/Task.scala b/core/src/mill/define/Task.scala
index f74171ec..a94d9703 100644
--- a/core/src/mill/define/Task.scala
+++ b/core/src/mill/define/Task.scala
@@ -289,7 +289,7 @@ class Command[+T](t: Task[T],
 }
 
 class Worker[+T](t: Task[T], ctx0: mill.define.Ctx) extends NamedTaskImpl[T](ctx0, t) {
-
+  override def flushDest = false
   override def asWorker = Some(this)
 }
 class Persistent[+T](t: Task[T],
diff --git a/core/src/mill/eval/Evaluator.scala b/core/src/mill/eval/Evaluator.scala
index 31b59865..21e3d3a9 100644
--- a/core/src/mill/eval/Evaluator.scala
+++ b/core/src/mill/eval/Evaluator.scala
@@ -12,21 +12,21 @@ import mill.util.Strict.Agg
 
 import scala.collection.mutable
 import scala.util.control.NonFatal
-case class Labelled[T](target: NamedTask[T],
+case class Labelled[T](task: NamedTask[T],
                        segments: Segments){
-  def format = target match{
+  def format = task match{
     case t: Target[T] => Some(t.readWrite.asInstanceOf[upickle.default.ReadWriter[T]])
     case _ => None
   }
-  def writer = target match{
+  def writer = task match{
     case t: mill.define.Command[T] => Some(t.writer.asInstanceOf[upickle.default.Writer[T]])
     case t: Target[T] => Some(t.readWrite.asInstanceOf[upickle.default.ReadWriter[T]])
     case _ => None
   }
 }
-class Evaluator[T](val workspacePath: Path,
-                   val basePath: Path,
-                   val externalBasePath: Path,
+class Evaluator[T](val outPath: Path,
+                   val millSourcePath: Path,
+                   val externalOutPath: Path,
                    val rootModule: mill.Module,
                    val discover: Discover[T],
                    log: Logger,
@@ -35,7 +35,7 @@ class Evaluator[T](val workspacePath: Path,
 
   val workerCache = mutable.Map.empty[Segments, (Int, Any)]
   def evaluate(goals: Agg[Task[_]]): Evaluator.Results = {
-    mkdir(workspacePath)
+    mkdir(outPath)
 
     val transitive = Graph.transitiveTargets(goals)
     val topoSorted = Graph.topoSorted(transitive)
@@ -125,8 +125,13 @@ class Evaluator[T](val workspacePath: Path,
           counterMsg = counterMsg
         )
       case Right(labelledNamedTask) =>
-        val paths = Evaluator.resolveDestPaths(workspacePath, labelledNamedTask.segments)
-        val groupBasePath = basePath / Evaluator.makeSegmentStrings(labelledNamedTask.segments)
+
+        val paths = if (labelledNamedTask.task.asTarget.exists(rootModule.millInternal.targets.contains)){
+          Evaluator.resolveDestPaths(outPath, labelledNamedTask.segments)
+        }else{
+          Evaluator.resolveDestPaths(externalOutPath, labelledNamedTask.segments)
+        }
+        val groupBasePath = millSourcePath / Evaluator.makeSegmentStrings(labelledNamedTask.segments)
         mkdir(paths.out)
         val cached = for{
           json <- scala.util.Try(upickle.json.read(read(paths.meta))).toOption
@@ -136,14 +141,14 @@ class Evaluator[T](val workspacePath: Path,
           parsed <- reader.read.lift(terminalResult)
         } yield parsed
 
-        val workerCached = labelledNamedTask.target.asWorker
+        val workerCached = labelledNamedTask.task.asWorker
           .flatMap{w => workerCache.get(w.ctx.segments)}
           .collect{case (`inputsHash`, v) => v}
 
         workerCached.map((_, inputsHash)) orElse cached.map(p => (p, p.hashCode())) match{
           case Some((v, hashCode)) =>
             val newResults = mutable.LinkedHashMap.empty[Task[_], Result[(Any, Int)]]
-            newResults(labelledNamedTask.target) = Result.Success((v, hashCode))
+            newResults(labelledNamedTask.task) = Result.Success((v, hashCode))
 
             (newResults, Nil)
 
@@ -155,7 +160,8 @@ class Evaluator[T](val workspacePath: Path,
               case Segment.Cross(s) => "[" + s.mkString(",") + "]"
             }
 
-            if (labelledNamedTask.target.flushDest) rm(paths.dest)
+            if (labelledNamedTask.task.flushDest) rm(paths.dest)
+
             val (newResults, newEvaluated) = evaluateGroup(
               group,
               results,
@@ -166,9 +172,9 @@ class Evaluator[T](val workspacePath: Path,
               counterMsg = counterMsg
             )
 
-            newResults(labelledNamedTask.target) match{
+            newResults(labelledNamedTask.task) match{
               case Result.Success((v, hashCode)) =>
-                labelledNamedTask.target.asWorker match{
+                labelledNamedTask.task.asWorker match{
                   case Some(w) =>
                     workerCache(w.ctx.segments) = (inputsHash, v)
                   case None =>
diff --git a/core/src/mill/main/RunScript.scala b/core/src/mill/main/RunScript.scala
index f09acf66..dfe49c57 100644
--- a/core/src/mill/main/RunScript.scala
+++ b/core/src/mill/main/RunScript.scala
@@ -185,7 +185,7 @@ object RunScript{
           t match {
             case t: mill.define.NamedTask[_] =>
               val jsonFile = Evaluator
-                .resolveDestPaths(evaluator.workspacePath, t.ctx.segments)
+                .resolveDestPaths(evaluator.outPath, t.ctx.segments)
                 .meta
               val metadata = upickle.json.read(jsonFile.toIO)
               Some(metadata(1))
diff --git a/core/test/resources/examples/javac/build.sc b/core/test/resources/examples/javac/build.sc
index 4a0882c6..8f250014 100644
--- a/core/test/resources/examples/javac/build.sc
+++ b/core/test/resources/examples/javac/build.sc
@@ -5,8 +5,8 @@ import mill.eval.PathRef
 import mill.modules.Jvm
 import mill.util.Loose
 
-def sourceRootPath = basePath / 'src
-def resourceRootPath = basePath / 'resources
+def sourceRootPath = millSourcePath / 'src
+def resourceRootPath = millSourcePath / 'resources
 
 // sourceRoot -> allSources -> classFiles
 //                                |
diff --git a/core/test/src/mill/define/BasePathTests.scala b/core/test/src/mill/define/BasePathTests.scala
index 62f84787..f7a1afa7 100644
--- a/core/test/src/mill/define/BasePathTests.scala
+++ b/core/test/src/mill/define/BasePathTests.scala
@@ -8,7 +8,7 @@ object BasePathTests extends TestSuite{
   val testGraphs = new TestGraphs
   val tests = Tests{
     def check(m: Module, segments: String*) = {
-      val remaining = m.basePath.relativeTo(pwd).segments.drop(1)
+      val remaining = m.millSourcePath.relativeTo(pwd).segments.drop(1)
       assert(remaining == segments)
     }
     'singleton - {
@@ -47,18 +47,18 @@ object BasePathTests extends TestSuite{
     }
     'overriden - {
       object overridenBasePath extends TestUtil.BaseModule {
-        override def basePath = pwd / 'overridenBasePathRootValue
+        override def millSourcePath = pwd / 'overridenBasePathRootValue
         object nested extends Module{
-          override def basePath = super.basePath / 'overridenBasePathNested
+          override def millSourcePath = super.millSourcePath / 'overridenBasePathNested
           object nested extends Module{
-            override def basePath = super.basePath / 'overridenBasePathDoubleNested
+            override def millSourcePath = super.millSourcePath / 'overridenBasePathDoubleNested
           }
         }
       }
       assert(
-        overridenBasePath.basePath == pwd / 'overridenBasePathRootValue,
-        overridenBasePath.nested.basePath == pwd / 'overridenBasePathRootValue / 'nested / 'overridenBasePathNested,
-        overridenBasePath.nested.nested.basePath == pwd / 'overridenBasePathRootValue / 'nested / 'overridenBasePathNested / 'nested / 'overridenBasePathDoubleNested
+        overridenBasePath.millSourcePath == pwd / 'overridenBasePathRootValue,
+        overridenBasePath.nested.millSourcePath == pwd / 'overridenBasePathRootValue / 'nested / 'overridenBasePathNested,
+        overridenBasePath.nested.nested.millSourcePath == pwd / 'overridenBasePathRootValue / 'nested / 'overridenBasePathNested / 'nested / 'overridenBasePathDoubleNested
       )
     }
 
diff --git a/core/test/src/mill/eval/ModuleTests.scala b/core/test/src/mill/eval/ModuleTests.scala
index 110e8c79..56c1a47b 100644
--- a/core/test/src/mill/eval/ModuleTests.scala
+++ b/core/test/src/mill/eval/ModuleTests.scala
@@ -26,7 +26,7 @@ object ModuleTests extends TestSuite{
       )
 
       val Right((30, 1)) = check.apply(Build.z)
-      val base = check.evaluator.workspacePath
+      val base = check.evaluator.outPath
       assert(
         read(base / 'z / "meta.json").contains("30"),
         read(base / 'mill / 'eval / 'ModuleTests / 'ExternalModule / 'x / "meta.json").contains("13"),
diff --git a/core/test/src/mill/util/TestEvaluator.scala b/core/test/src/mill/util/TestEvaluator.scala
index 3b34e27d..26577f3e 100644
--- a/core/test/src/mill/util/TestEvaluator.scala
+++ b/core/test/src/mill/util/TestEvaluator.scala
@@ -10,16 +10,16 @@ import utest.assert
 import language.experimental.macros
 object TestEvaluator{
   implicit def implicitDisover[T]: Discover[T] = macro applyImpl[T]
-  val externalBasePath = pwd / 'target / 'external
+  val externalOutPath = pwd / 'target / 'external
 }
 class TestEvaluator[T <: TestUtil.TestBuild](module: T,
                                              workspacePath: Path,
-                                             basePath: Path)
+                                             millSourcePath: Path)
                                             (implicit discover: Discover[T]){
-  val evaluator = new Evaluator(
-    workspacePath, basePath, TestEvaluator.externalBasePath, module, discover, DummyLogger
-  )
-//  val evaluator = new Evaluator(workspacePath, basePath, module, discover, new PrintLogger(true, ammonite.util.Colors.Default, System.out, System.out, System.err))
+  val logger = DummyLogger
+//  val logger = new PrintLogger(true, ammonite.util.Colors.Default, System.out, System.out, System.err)
+  val evaluator = new Evaluator(workspacePath, millSourcePath, TestEvaluator.externalOutPath, module, discover, logger)
+
   def apply[T](t: Task[T]): Either[Result.Failing, (T, Int)] = {
     val evaluated = evaluator.evaluate(Agg(t))
 
@@ -31,7 +31,7 @@ class TestEvaluator[T <: TestUtil.TestBuild](module: T,
             case t: Target[_]
               if module.millInternal.targets.contains(t)
               && !t.isInstanceOf[Input[_]] => t
-            case t: mill.define.Command[_]           => t
+            case t: mill.define.Command[_] => t
           }.size
         ))
     } else {
diff --git a/docs/cross.md b/docs/cross.md
index 25ae4a8a..fe14a23e 100644
--- a/docs/cross.md
+++ b/docs/cross.md
@@ -25,7 +25,7 @@ mill --show foo[2.12].suffix
 mill --show foo[2.12].bigSuffix
 ```
 
-The modules each also have a `basePath` of
+The modules each also have a `millSourcePath` of
 
 ```text
 foo/2.10
diff --git a/docs/modules.md b/docs/modules.md
index 86f807de..b92ab684 100644
--- a/docs/modules.md
+++ b/docs/modules.md
@@ -76,9 +76,9 @@ You can override targets and commands to customize them or change what they do.
 The overriden version is available via `super`. You can omit the `override`
 keyword in Mill builds.
 
-## basePath
+## millSourcePath
 
-Each Module has a `basePath` field that corresponds to the path that module
+Each Module has a `millSourcePath` field that corresponds to the path that module
 expects it's input files to be on disk. Re-visiting our examples above:
 
 ```scala
@@ -90,24 +90,24 @@ object foo extends mill.Module{
 }
 ```
 
-The `foo` module has a `basePath` of `./foo`, while the `foo.baz` module has a
-`basePath` of `./foo/baz`.
+The `foo` module has a `millSourcePath` of `./foo`, while the `foo.baz` module has a
+`millSourcePath` of `./foo/baz`.
 
-You can use `basePath` to automatically set the source directories of your
+You can use `millSourcePath` to automatically set the source directories of your
 modules to match the build structure. You are not forced to rigidly use
-`basePath` to define the source folders of all your code, but it can simplify
+`millSourcePath` to define the source folders of all your code, but it can simplify
 the common case where you probably want your build-layout on on-disk-layout to
 be the same.
 
 e.g. for `mill.scalalib.ScalaModule`, the Scala source code is assumed by
-default to be in `basePath/"src"` while resources are automatically assumed to
-be in `basePath/"resources"`.
+default to be in `millSourcePath/"src"` while resources are automatically assumed to
+be in `millSourcePath/"resources"`.
 
-You can override `basePath`:
+You can override `millSourcePath`:
 
 ```scala
 object foo extends mill.Module{
-  def basePath = super.basePath / "lols"
+  def millSourcePath = super.millSourcePath / "lols"
   def bar = T{ "hello" }
   object baz extends mill.Module{
     def qux = T{ "world" } 
@@ -116,10 +116,10 @@ object foo extends mill.Module{
 ```
 
 And any overrides propagate down to the module's children: in the above example,
-module `foo` would have it's `basePath` be `./foo/lols` while module` foo.baz`
-would have it's `basePath` be `./foo/lols/baz`.
+module `foo` would have it's `millSourcePath` be `./foo/lols` while module` foo.baz`
+would have it's `millSourcePath` be `./foo/lols/baz`.
 
-Note that `basePath` is generally only used for a module's input source files.
+Note that `millSourcePath` is generally only used for a module's input source files.
 Output is always in the `out/` folder and cannot be changed, e.g. even with the
-overriden `basePath` the output paths are still the default `./out/foo/bar` and
+overriden `millSourcePath` the output paths are still the default `./out/foo/bar` and
 `./out/foo/baz/qux` folders.
\ No newline at end of file
diff --git a/integration/test/resources/acyclic/build.sc b/integration/test/resources/acyclic/build.sc
index b8f878ad..5328db24 100644
--- a/integration/test/resources/acyclic/build.sc
+++ b/integration/test/resources/acyclic/build.sc
@@ -4,7 +4,7 @@ import mill.scalalib.publish.{PomSettings, License, Developer, SCM}
 
 object acyclic extends Cross[AcyclicModule]("2.10.6", "2.11.8", "2.12.3", "2.12.4")
 class AcyclicModule(val crossScalaVersion: String) extends CrossSbtModule with PublishModule {
-  def basePath = super.basePath / ammonite.ops.up
+  def millSourcePath = super.millSourcePath / ammonite.ops.up
   def artifactName = "acyclic"
   def publishVersion = "0.1.7"
 
diff --git a/integration/test/resources/ammonite/build.sc b/integration/test/resources/ammonite/build.sc
index 4b8db461..f8732a4c 100644
--- a/integration/test/resources/ammonite/build.sc
+++ b/integration/test/resources/ammonite/build.sc
@@ -59,7 +59,7 @@ object amm extends Cross[MainModule](fullCrossScalaVersions:_*){
     def generatedSources = T{
       import ammonite.ops._
       mkdir(T.ctx().dest)
-      cp(build.basePath/'project/"Constants.scala", T.ctx().dest/"Constants.scala")
+      cp(build.millSourcePath/'project/"Constants.scala", T.ctx().dest/"Constants.scala")
       Seq(PathRef(T.ctx().dest))
     }
   }
diff --git a/integration/test/resources/jawn/build.sc b/integration/test/resources/jawn/build.sc
index ac9de195..b83eac17 100644
--- a/integration/test/resources/jawn/build.sc
+++ b/integration/test/resources/jawn/build.sc
@@ -4,7 +4,7 @@ import mill.scalalib.{Dep, TestModule, DepSyntax, Lib}
 import ammonite.ops.up
 object jawn extends Cross[JawnModule]("2.10.6", "2.11.11", "2.12.3")
 class JawnModule(crossVersion: String) extends mill.Module{
-  override def basePath = super.basePath / up / up
+  override def millSourcePath = super.millSourcePath / up / up
 
   trait JawnModule extends scalalib.SbtModule{
     def scalaVersion = crossVersion
@@ -53,7 +53,7 @@ class JawnModule(crossVersion: String) extends mill.Module{
 
     object rojoma extends Support(ivy"com.rojoma::rojoma-json:2.4.3")
     object rojomaV3 extends Support(ivy"com.rojoma::rojoma-json-v3:3.7.2"){
-      override def basePath = super.basePath / up / "rojoma-v3"
+      override def millSourcePath = super.millSourcePath / up / "rojoma-v3"
     }
     object spray extends Support(ivy"io.spray::spray-json:1.3.3")
   }
diff --git a/scalajslib/test/src/mill/scalajslib/HelloJSWorldTests.scala b/scalajslib/test/src/mill/scalajslib/HelloJSWorldTests.scala
index 5ba4343f..fc419e27 100644
--- a/scalajslib/test/src/mill/scalajslib/HelloJSWorldTests.scala
+++ b/scalajslib/test/src/mill/scalajslib/HelloJSWorldTests.scala
@@ -20,7 +20,7 @@ object HelloJSWorldTests extends TestSuite {
 
 
   trait HelloJSWorldModule extends ScalaJSModule with PublishModule {
-    override def basePath = HelloJSWorldTests.workspacePath
+    override def millSourcePath = HelloJSWorldTests.workspacePath
     override def mainClass = Some("Main")
   }
 
@@ -36,7 +36,7 @@ object HelloJSWorldTests extends TestSuite {
     class BuildModuleUtest(scalaVersion0: String, sjsVersion0: String)
       extends BuildModule(scalaVersion0: String, sjsVersion0: String) {
       object test extends super.Tests {
-        override def sources = T.input{ Agg(PathRef(basePath / 'src / 'utest)) }
+        override def sources = T.input{ Agg(PathRef(millSourcePath / 'src / 'utest)) }
         def testFramework: T[String] = "utest.runner.Framework"
         override def ivyDeps = Agg(
           ivy"com.lihaoyi:utest_sjs${scalaJSBinaryVersion()}_${Lib.scalaBinaryVersion(scalaVersion())}:0.6.3"
@@ -48,7 +48,7 @@ object HelloJSWorldTests extends TestSuite {
     class BuildModuleScalaTest(scalaVersion0: String, sjsVersion0: String)
       extends BuildModule(scalaVersion0: String, sjsVersion0: String) {
       object test extends super.Tests {
-        override def sources = T.input{ Agg(PathRef(basePath / 'src / 'scalatest)) }
+        override def sources = T.input{ Agg(PathRef(millSourcePath / 'src / 'scalatest)) }
         def testFramework: T[String] = "org.scalatest.tools.Framework"
         override def ivyDeps = Agg(
           ivy"org.scalatest:scalatest_sjs${scalaJSBinaryVersion()}_${Lib.scalaBinaryVersion(scalaVersion())}:3.0.4"
@@ -76,7 +76,7 @@ object HelloJSWorldTests extends TestSuite {
     }
   }
 
-  val srcPath = pwd / 'scalajslib / 'test / 'resources / "hello-js-world"
+  val millSourcePath = pwd / 'scalajslib / 'test / 'resources / "hello-js-world"
   val workspacePath = pwd / 'target / 'workspace / "hello-js-world"
   val outputPath = workspacePath / 'out
   val mainObject = workspacePath / 'src / "Main.scala"
@@ -84,7 +84,7 @@ object HelloJSWorldTests extends TestSuite {
   val helloWorldEvaluator = new TestEvaluator(
     HelloJSWorld,
     workspacePath,
-    srcPath
+    millSourcePath
   )
 
   class Console {
@@ -243,7 +243,7 @@ object HelloJSWorldTests extends TestSuite {
   def prepareWorkspace(): Unit = {
     rm(workspacePath)
     mkdir(workspacePath / up)
-    cp(srcPath, workspacePath)
+    cp(millSourcePath, workspacePath)
   }
 
 }
diff --git a/scalalib/src/mill/scalalib/GenIdea.scala b/scalalib/src/mill/scalalib/GenIdea.scala
index 99b820b0..60153f1f 100644
--- a/scalalib/src/mill/scalalib/GenIdea.scala
+++ b/scalalib/src/mill/scalalib/GenIdea.scala
@@ -116,7 +116,7 @@ object GenIdea {
       val normalSourcePaths = (allSourcesPathRefs.map(_.path).toSet -- generatedSourcePaths.toSet).toSeq
 
       val paths = Evaluator.resolveDestPaths(
-        evaluator.workspacePath,
+        evaluator.outPath,
         mod.compile.ctx.segments
       )
 
diff --git a/scalalib/src/mill/scalalib/MiscModule.scala b/scalalib/src/mill/scalalib/MiscModule.scala
index e20fe7be..440b7dcd 100644
--- a/scalalib/src/mill/scalalib/MiscModule.scala
+++ b/scalalib/src/mill/scalalib/MiscModule.scala
@@ -14,7 +14,7 @@ object CrossModuleBase{
 }
 trait CrossModuleBase extends mill.Module{
   def crossScalaVersion: String
-  override def basePath = super.basePath / ammonite.ops.up
+  override def millSourcePath = super.millSourcePath / ammonite.ops.up
   implicit def crossSbtModuleResolver: Resolver[CrossModuleBase] = new Resolver[CrossModuleBase]{
     def resolve[V <: CrossModuleBase](c: Cross[V]): V = {
       crossScalaVersion.split('.')
@@ -37,14 +37,14 @@ trait CrossModuleBase extends mill.Module{
 trait CrossScalaModule extends ScalaModule with CrossModuleBase{ outer =>
   override def sources = T.input{
     super.sources() ++
-    CrossModuleBase.scalaVersionPaths(crossScalaVersion, s => basePath / s"src-$s" )
+    CrossModuleBase.scalaVersionPaths(crossScalaVersion, s => millSourcePath / s"src-$s" )
 
   }
 
   trait Tests extends super.Tests {
     override def sources = T.input{
       super.sources() ++
-      CrossModuleBase.scalaVersionPaths(crossScalaVersion, s => basePath / s"src-$s" )
+      CrossModuleBase.scalaVersionPaths(crossScalaVersion, s => millSourcePath / s"src-$s" )
     }
   }
 }
@@ -52,20 +52,20 @@ trait CrossScalaModule extends ScalaModule with CrossModuleBase{ outer =>
 trait SbtModule extends ScalaModule { outer =>
   override def sources = T.input{
     Agg(
-      PathRef(basePath / 'src / 'main / 'scala),
-      PathRef(basePath / 'src / 'main / 'java)
+      PathRef(millSourcePath / 'src / 'main / 'scala),
+      PathRef(millSourcePath / 'src / 'main / 'java)
     )
   }
-  override def resources = T.input{ Agg(PathRef(basePath / 'src / 'main / 'resources)) }
+  override def resources = T.input{ Agg(PathRef(millSourcePath / 'src / 'main / 'resources)) }
   trait Tests extends super.Tests {
-    override def basePath = outer.basePath
+    override def millSourcePath = outer.millSourcePath
     override def sources = T.input{
       Agg(
-        PathRef(basePath / 'src / 'test / 'scala),
-        PathRef(basePath / 'src / 'test / 'java)
+        PathRef(millSourcePath / 'src / 'test / 'scala),
+        PathRef(millSourcePath / 'src / 'test / 'java)
       )
     }
-    override def resources = T.input{ Agg(PathRef(basePath / 'src / 'test / 'resources)) }
+    override def resources = T.input{ Agg(PathRef(millSourcePath / 'src / 'test / 'resources)) }
   }
 }
 
@@ -76,17 +76,17 @@ trait CrossSbtModule extends SbtModule with CrossModuleBase{ outer =>
     super.sources() ++
     CrossModuleBase.scalaVersionPaths(
       crossScalaVersion,
-      s => basePath / 'src / 'main / s"scala-$s"
+      s => millSourcePath / 'src / 'main / s"scala-$s"
     )
 
   }
   trait Tests extends super.Tests {
-    override def basePath = outer.basePath
+    override def millSourcePath = outer.millSourcePath
     override def sources = T.input{
       super.sources() ++
       CrossModuleBase.scalaVersionPaths(
         crossScalaVersion,
-        s => basePath / 'src / 'main / s"scala-$s"
+        s => millSourcePath / 'src / 'main / s"scala-$s"
       )
     }
   }
diff --git a/scalalib/src/mill/scalalib/ScalaModule.scala b/scalalib/src/mill/scalalib/ScalaModule.scala
index 47326c6c..47309350 100644
--- a/scalalib/src/mill/scalalib/ScalaModule.scala
+++ b/scalalib/src/mill/scalalib/ScalaModule.scala
@@ -126,8 +126,8 @@ trait ScalaModule extends mill.Module with TaskModule { outer =>
 
   def prependShellScript: T[String] = T{ "" }
 
-  def sources = T.input{ Agg(PathRef(basePath / 'src)) }
-  def resources = T.input{ Agg(PathRef(basePath / 'resources)) }
+  def sources = T.input{ Agg(PathRef(millSourcePath / 'src)) }
+  def resources = T.input{ Agg(PathRef(millSourcePath / 'resources)) }
   def generatedSources = T { Agg.empty[PathRef] }
   def allSources = T{ sources() ++ generatedSources() }
 
@@ -249,7 +249,7 @@ trait ScalaModule extends mill.Module with TaskModule { outer =>
   // publish artifact with name "mill_2.12.4" instead of "mill_2.12"
   def crossFullScalaVersion: T[Boolean] = false
 
-  def artifactName: T[String] = basePath.last.toString
+  def artifactName: T[String] = millSourcePath.last.toString
   def artifactScalaVersion: T[String] = T {
     if (crossFullScalaVersion()) scalaVersion()
     else Lib.scalaBinaryVersion(scalaVersion())
diff --git a/scalalib/test/src/mill/scalalib/GenIdeaTests.scala b/scalalib/test/src/mill/scalalib/GenIdeaTests.scala
index 58992e4f..00d9f53e 100644
--- a/scalalib/test/src/mill/scalalib/GenIdeaTests.scala
+++ b/scalalib/test/src/mill/scalalib/GenIdeaTests.scala
@@ -8,13 +8,13 @@ import utest._
 import mill.util.TestEvaluator.implicitDisover
 object GenIdeaTests extends TestSuite {
 
-  val basePath = pwd / 'target / 'workspace / "gen-idea"
-  val outPath = basePath / 'out
-  val workingSrcPath = basePath / 'src
+  val millSourcePath = pwd / 'target / 'workspace / "gen-idea"
+  val outPath = millSourcePath / 'out
+  val workingSrcPath = millSourcePath / 'src
 
   trait HelloWorldModule extends scalalib.ScalaModule {
     def scalaVersion = "2.12.4"
-    def basePath = HelloWorldTests.workingSrcPath
+    def millSourcePath = HelloWorldTests.workingSrcPath
   }
 
   object HelloWorld extends TestUtil.BaseModule with HelloWorldModule
@@ -32,34 +32,34 @@ object GenIdeaTests extends TestSuite {
 
       val layout = GenIdea.xmlFileLayout(helloWorldEvaluator.evaluator, HelloWorld, fetchMillModules = false)
       for((relPath, xml) <- layout){
-        write.over(basePath/ "generated"/ relPath, pp.format(xml))
+        write.over(millSourcePath/ "generated"/ relPath, pp.format(xml))
       }
 
       Seq(
         "gen-idea/idea_modules/iml" ->
-          basePath / "generated" / ".idea_modules" /".iml",
+          millSourcePath / "generated" / ".idea_modules" /".iml",
         "gen-idea/idea_modules/root.iml" ->
-          basePath / "generated" / ".idea_modules" /"root.iml",
+          millSourcePath / "generated" / ".idea_modules" /"root.iml",
         "gen-idea/idea/libraries/scala-reflect_2.12.4_scala-reflect-2.12.4-sources.jar.xml" ->
-          basePath / "generated" / ".idea" / "libraries" / "scala-reflect_2.12.4_scala-reflect-2.12.4-sources.jar.xml",
+          millSourcePath / "generated" / ".idea" / "libraries" / "scala-reflect_2.12.4_scala-reflect-2.12.4-sources.jar.xml",
         "gen-idea/idea/libraries/scala-reflect_2.12.4_scala-reflect-2.12.4.jar.xml" ->
-          basePath / "generated" / ".idea" / "libraries" / "scala-reflect_2.12.4_scala-reflect-2.12.4.jar.xml",
+          millSourcePath / "generated" / ".idea" / "libraries" / "scala-reflect_2.12.4_scala-reflect-2.12.4.jar.xml",
         "gen-idea/idea/libraries/scala-library_2.12.4_scala-library-2.12.4.jar.xml" ->
-          basePath / "generated" / ".idea" / "libraries" / "scala-library_2.12.4_scala-library-2.12.4.jar.xml",
+          millSourcePath / "generated" / ".idea" / "libraries" / "scala-library_2.12.4_scala-library-2.12.4.jar.xml",
         "gen-idea/idea/libraries/modules_scala-xml_2.12_1.0.6_scala-xml_2.12-1.0.6.jar.xml" ->
-          basePath / "generated" / ".idea" / "libraries" / "modules_scala-xml_2.12_1.0.6_scala-xml_2.12-1.0.6.jar.xml",
+          millSourcePath / "generated" / ".idea" / "libraries" / "modules_scala-xml_2.12_1.0.6_scala-xml_2.12-1.0.6.jar.xml",
         "gen-idea/idea/libraries/modules_scala-xml_2.12_1.0.6_scala-xml_2.12-1.0.6-sources.jar.xml" ->
-          basePath / "generated" / ".idea" / "libraries" / "modules_scala-xml_2.12_1.0.6_scala-xml_2.12-1.0.6-sources.jar.xml",
+          millSourcePath / "generated" / ".idea" / "libraries" / "modules_scala-xml_2.12_1.0.6_scala-xml_2.12-1.0.6-sources.jar.xml",
         "gen-idea/idea/libraries/scala-compiler_2.12.4_scala-compiler-2.12.4-sources.jar.xml" ->
-          basePath / "generated" / ".idea" / "libraries" / "scala-compiler_2.12.4_scala-compiler-2.12.4-sources.jar.xml",
+          millSourcePath / "generated" / ".idea" / "libraries" / "scala-compiler_2.12.4_scala-compiler-2.12.4-sources.jar.xml",
         "gen-idea/idea/libraries/scala-library_2.12.4_scala-library-2.12.4-sources.jar.xml" ->
-          basePath / "generated" / ".idea" / "libraries" / "scala-library_2.12.4_scala-library-2.12.4-sources.jar.xml",
+          millSourcePath / "generated" / ".idea" / "libraries" / "scala-library_2.12.4_scala-library-2.12.4-sources.jar.xml",
         "gen-idea/idea/libraries/scala-compiler_2.12.4_scala-compiler-2.12.4.jar.xml" ->
-          basePath / "generated" / ".idea" / "libraries" / "scala-compiler_2.12.4_scala-compiler-2.12.4.jar.xml",
+          millSourcePath / "generated" / ".idea" / "libraries" / "scala-compiler_2.12.4_scala-compiler-2.12.4.jar.xml",
         "gen-idea/idea/modules.xml" ->
-          basePath / "generated" / ".idea" / "modules.xml",
+          millSourcePath / "generated" / ".idea" / "modules.xml",
         "gen-idea/idea/misc.xml" ->
-          basePath / "generated" / ".idea" / "misc.xml"
+          millSourcePath / "generated" / ".idea" / "misc.xml"
       ).foreach { case (resource, generated) =>
           val resourceString = scala.io.Source.fromResource(resource).getLines().mkString("\n")
           val generatedString = normaliseLibraryPaths(read! generated)
diff --git a/scalalib/test/src/mill/scalalib/HelloWorldTests.scala b/scalalib/test/src/mill/scalalib/HelloWorldTests.scala
index 06d650c1..cecc9349 100644
--- a/scalalib/test/src/mill/scalalib/HelloWorldTests.scala
+++ b/scalalib/test/src/mill/scalalib/HelloWorldTests.scala
@@ -17,7 +17,7 @@ import scala.collection.JavaConverters._
 object HelloWorldTests extends TestSuite {
   trait HelloWorldModule extends scalalib.ScalaModule {
     def scalaVersion = "2.12.4"
-    def basePath = HelloWorldTests.workingSrcPath
+    def millSourcePath = HelloWorldTests.workingSrcPath
   }
 
   object HelloWorld extends TestUtil.BaseModule with HelloWorldModule
@@ -73,10 +73,10 @@ object HelloWorldTests extends TestSuite {
   object HelloWorldScalaOverride extends TestUtil.BaseModule with HelloWorldModule {
     override def scalaVersion: Target[String] = "2.11.11"
   }
-  val srcPath = pwd / 'scalalib / 'test / 'resources / "hello-world"
-  val basePath = pwd / 'target / 'workspace / "hello-world"
-  val workingSrcPath = basePath / 'src
-  val outPath = basePath / 'out
+  val resourcePath = pwd / 'scalalib / 'test / 'resources / "hello-world"
+  val millSourcePath = pwd / 'target / 'workspace / "hello-world"
+  val workingSrcPath = millSourcePath / 'src
+  val outPath = millSourcePath / 'out
   val mainObject = workingSrcPath / 'src / "Main.scala"
 
 
@@ -211,7 +211,7 @@ object HelloWorldTests extends TestSuite {
     }
     'runMain - {
       'runMainObject - {
-        val runResult = basePath / 'out / 'runMain / 'dest / "hello-mill"
+        val runResult = millSourcePath / 'out / 'runMain / 'dest / "hello-mill"
 
         val Right((_, evalCount)) = helloWorldEvaluator(HelloWorld.runMain("Main", runResult.toString))
         assert(evalCount > 0)
@@ -224,7 +224,7 @@ object HelloWorldTests extends TestSuite {
       'runCross{
         def cross(v: String) {
 
-          val runResult = basePath / 'out / 'cross / v / 'runMain / 'dest / "hello-mill"
+          val runResult = millSourcePath / 'out / 'cross / v / 'runMain / 'dest / "hello-mill"
 
           val Right((_, evalCount)) = helloWorldCrossEvaluator(
             CrossHelloWorld.cross(v).runMain("Main", runResult.toString)
@@ -265,7 +265,7 @@ object HelloWorldTests extends TestSuite {
 
     'forkRun - {
       'runIfMainClassProvided - {
-        val runResult = basePath / 'out / 'run / 'dest / "hello-mill"
+        val runResult = millSourcePath / 'out / 'run / 'dest / "hello-mill"
         val Right((_, evalCount)) = helloWorldWithMainEvaluator(
           HelloWorldWithMain.run(runResult.toString)
         )
@@ -288,7 +288,7 @@ object HelloWorldTests extends TestSuite {
     }
     'run - {
       'runIfMainClassProvided - {
-        val runResult = basePath / 'out / 'run / 'dest / "hello-mill"
+        val runResult = millSourcePath / 'out / 'run / 'dest / "hello-mill"
         val Right((_, evalCount)) = helloWorldWithMainEvaluator(
           HelloWorldWithMain.runLocal(runResult.toString)
         )
@@ -364,9 +364,9 @@ object HelloWorldTests extends TestSuite {
           exists(result.path),
           evalCount > 0
         )
-        val runResult = basePath / "hello-mill"
+        val runResult = millSourcePath / "hello-mill"
 
-        %%("java", "-jar", result.path, runResult)(wd = basePath)
+        %%("java", "-jar", result.path, runResult)(wd = millSourcePath)
 
         assert(
           exists(runResult),
@@ -394,7 +394,7 @@ object HelloWorldTests extends TestSuite {
     rm(outPath)
     rm(workingSrcPath)
     mkdir(outPath)
-    cp(srcPath, workingSrcPath)
+    cp(resourcePath, workingSrcPath)
   }
 
 }
diff --git a/scalaworker/src/mill/scalaworker/ScalaWorker.scala b/scalaworker/src/mill/scalaworker/ScalaWorker.scala
index 45b2b927..62fc7f58 100644
--- a/scalaworker/src/mill/scalaworker/ScalaWorker.scala
+++ b/scalaworker/src/mill/scalaworker/ScalaWorker.scala
@@ -95,6 +95,7 @@ class ScalaWorker(ctx0: mill.util.Ctx,
         .get
         .invoke(null, argsArray)
     }
+
     compiledDest
   }