Use the classloader that defines the `build.sc` root Module to get a classpath signature, to ensure that changes to the root module definition flush caches

2 files changed, 8 insertions, 2 deletions

diff --git a/core/src/main/scala/mill/eval/Evaluator.scala b/core/src/main/scala/mill/eval/Evaluator.scala
index 8f9ff8a2..44f24275 100644
--- a/core/src/main/scala/mill/eval/Evaluator.scala
+++ b/core/src/main/scala/mill/eval/Evaluator.scala
@@ -34,7 +34,6 @@ class Evaluator[T](val workspacePath: Path,
                    val classLoaderSig: Seq[(Path, Long)] = Evaluator.classLoaderSig){
 
 
-
   val workerCache = mutable.Map.empty[Ctx.Loader[_], Any]
   workerCache(RootModuleLoader) = rootModule
   def evaluate(goals: Agg[Task[_]]): Evaluator.Results = {
diff --git a/core/src/main/scala/mill/main/RunScript.scala b/core/src/main/scala/mill/main/RunScript.scala
index 010f134b..aa254048 100644
--- a/core/src/main/scala/mill/main/RunScript.scala
+++ b/core/src/main/scala/mill/main/RunScript.scala
@@ -4,6 +4,7 @@ import java.nio.file.NoSuchFileException
 
 import ammonite.interp.Interpreter
 import ammonite.ops.{Path, read}
+import ammonite.runtime.SpecialClassLoader
 import ammonite.util.Util.CodeSource
 import ammonite.util.{Name, Res, Util}
 import mill.{PathRef, define}
@@ -40,7 +41,13 @@ object RunScript{
             interp.watch(path)
             val eval =
               for((mapping, discover) <- evaluateMapping(wd, path, interp))
-              yield (new Evaluator(wd / 'out, wd, mapping, log), discover)
+              yield (
+                new Evaluator(
+                  wd / 'out, wd, mapping, log,
+                  mapping.getClass.getClassLoader.asInstanceOf[SpecialClassLoader].classpathSignature
+                ),
+                discover
+              )
             (eval, interp.watchedFiles)
         }
     }