Occasional flakiness in CI with .mill.yaml files #6764
Description
e.g. in https://github.com/com-lihaoyi/mill/actions/runs/21615609451/job/62294255358, example.scalalib.module.3-docjar failed with
10762] example.scalalib.module.3-docjar.testForked
10762] Running Test Class mill.testkit.UtestExampleTestSuite
10762] -------------------------------- Running Tests --------------------------------
10762] Preparing integration test in /home/runner/work/mill/mill/out/integration/sharedOutFolder.dest/SNAPSHOT/shared-0/out
10762] Re-using out folder
10762]
10762] Running (in-memory):
10762] /home/runner/work/mill/mill/out/integration/sharedOutFolder.dest/SNAPSHOT/shared-0/out> mill --ticker false show foo.docJar (in-memory)
10762] --- Expected output ----------
10762] "ref:...out/foo/docJar.dest/out.jar"
10762] ------------------------------
10762] compiling 1 Scala source to out/mill-build/compile.dest/classes ...
10762] done compiling
10762] compiling 2 Scala sources to out/mill-build/compile.dest/classes ...
10762] done compiling
10762] [error] foo/package.mill.yaml:2:1
10762] scalaVersion: 3.3.6
10762] ^
10762] show key "scalaVersion" does not override any task on ScalaModule
10762]
10762] Failure:
10762] /home/runner/work/mill/mill/out/integration/sharedOutFolder.dest/SNAPSHOT/shared-0/out> mill --ticker false show foo.docJar (in-memory)
10762]
10762]
10762] Running (in-memory):
10762] /home/runner/work/mill/mill/out/integration/sharedOutFolder.dest/SNAPSHOT/shared-0/out> mill --ticker false clean (in-memory)
10762] --- Expected output ----------
10762]
10762] ------------------------------
10762] Success:
10762] /home/runner/work/mill/mill/out/integration/sharedOutFolder.dest/SNAPSHOT/shared-0/out> mill --ticker false clean (in-memory)
10762]
10762] java.util.concurrent.ExecutionException: Boxed Exception
10762] at scala.concurrent.impl.Promise$.scala$concurrent$impl$Promise$$$resolve(Promise.scala:102)
10762] at scala.concurrent.impl.Promise$DefaultPromise.tryComplete(Promise.scala:291)
10762] at scala.concurrent.Promise.complete(Promise.scala:58)
10762] at scala.concurrent.Promise.complete$(Promise.scala:37)
10762] at scala.concurrent.impl.Promise$DefaultPromise.complete(Promise.scala:107)
10762] at mill.util.Retry.rec$1$$anonfun$1(Retry.scala:50)
10762] at mill.api.daemon.StartThread$.$anonfun$1(SpawnThread.scala:5)
10762] at java.base/java.lang.Thread.run(Thread.java:1583)
10762] Caused by: utest.AssertionError: evalResult.exitCode == 0
10762] evalResult: EvalResult = EvalResult(
10762] command = List("mill", "--ticker", "false", "show", "foo.docJar"),
10762] exitCode = 1,
10762] outErr = """compiling 1 Scala source to out/mill-build/compile.dest/classes ...
10762] done compiling
10762] compiling 2 Scala sources to out/mill-build/compile.dest/classes ...
10762] done compiling
10762] [error] foo/package.mill.yaml:2:1
10762] scalaVersion: 3.3.6
10762] ^
10762] show key "scalaVersion" does not override any task on ScalaModule
10762]
10762] """
10762] )
10762] evalResult.exitCode != 0:
10762] - 1
10762] + 0
10762]
10762] at utest.AssertionError$.apply(Errors.scala:18)
10762] at utest.asserts.Util$.makeAssertError$$anonfun$1(Util.scala:26)
10762] at utest.framework.StackMarker$.dropInside(StackMarker.scala:11)
10762] at utest.asserts.Util$.makeAssertError(Util.scala:29)
10762] at utest.asserts.Asserts$.assertImpl(Asserts.scala:30)
10762] at mill.testkit.ExampleTester.validateEval(ExampleTester.scala:262)
10762] at mill.testkit.ExampleTester.runAndValidate(ExampleTester.scala:185)
10762] at mill.testkit.ExampleTester.processCommand(ExampleTester.scala:153)
10762] at mill.testkit.ExampleTester.processCommandBlock(ExampleTester.scala:119)
10762] at mill.testkit.ExampleTester.run$$anonfun$1(ExampleTester.scala:322)
10762] at scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
10762] at scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
10762] at scala.collection.ArrayOps$.foreach$extension(ArrayOps.scala:1324)
10762] at mill.testkit.ExampleTester.run(ExampleTester.scala:322)
10762] at mill.testkit.ExampleTester$.run(ExampleTester.scala:77)
10762] at mill.testkit.UtestExampleTestSuite$.run$1$$anonfun$1(UtestExampleTestSuite.scala:28)
10762] at mill.util.Retry.apply$$anonfun$1(Retry.scala:40)
10762] at mill.util.Retry.apply$$anonfun$adapted$1(Retry.scala:40)
10762] at mill.util.Retry.rec$1$$anonfun$1$$anonfun$1(Retry.scala:50)
10762] at scala.util.Try$.apply(Try.scala:218)
10762] ... 3 more
10762]
10762] Attempt 1 failed, waiting 10 ms
10762] Preparing integration test in /home/runner/work/mill/mill/out/integration/sharedOutFolder.dest/SNAPSHOT/shared-0/out
10762] Re-using out folder
10762]
10762] Running (in-memory):
10762] /home/runner/work/mill/mill/out/integration/sharedOutFolder.dest/SNAPSHOT/shared-0/out> mill --ticker false show foo.docJar (in-memory)
10762] --- Expected output ----------
10762] "ref:...out/foo/docJar.dest/out.jar"
10762] ------------------------------
10761] [warn] there was 1 deprecation warning; re-run with -deprecation for details
10761] [warn] one warning found
10762] [error] foo/package.mill.yaml:2:1
10761] done compiling
10762] scalaVersion: 3.3.6
10762] ^
10762] show key "scalaVersion" does not override any task on ScalaModule
10762]
10762] Failure:
10762] /home/runner/work/mill/mill/out/integration/sharedOutFolder.dest/SNAPSHOT/shared-0/out> mill --ticker false show foo.docJar (in-memory)
10762]
10762]
show key "scalaVersion" does not override any task on ScalaModule seems broken, since ScalaModule does in fact have a scalaVersion task. So something must be broken, perhaps related to the invalidation logic around .mill.yaml files, such that even though Mill knows the module is of type scalaVersion, the does not override any task check is working off some stale data and thinks scalaVersion is invalid