Bump SBT 1.12.6, Scala 2.13.18/3.3.7, and all build plugins

.github/workflows/build.yml

@@ -2,10 +2,10 @@ name: build
 
 on:
   pull_request:
-    branches: ['series/*']
+    branches: [ 'series/*' ]
   push:
-    branches: ['series/*']
-    tags: ["v[0-9]+*"]
+    branches: [ 'series/*' ]
+    tags: [ "v[0-9]+*" ]
 
 jobs:
   jvm-tests:
@@ -17,7 +17,7 @@ jobs:
         java: [ 11 ]
         # WARN: build.sbt depends on this key path, as scalaVersion and
         # crossScalaVersions is determined from it
-        scala: [ 2.13.8, 3.1.2 ]
+        scala: [ 2.13.18, 3.3.7 ]
 
     env:
       CI: true
@@ -65,8 +65,8 @@ jobs:
         # WARN: build.sbt depends on this key path, as scalaVersion and
         # crossScalaVersions is determined from it
         include:
-          - { java: 11, scala: 2.13.8 }
-          - { java: 11, scala: 3.1.2 }
+          - { java: 11, scala: 2.13.18 }
+          - { java: 11, scala: 3.3.7 }
 
     env:
       CI: true
@@ -118,8 +118,8 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - { java: 11, scala: 2.13.8 }
-          - { java: 11, scala: 3.1.2 }
+          - { java: 11, scala: 2.13.18 }
+          - { java: 11, scala: 3.3.7 }
 
     steps:
       - uses: actions/checkout@v4
@@ -162,9 +162,9 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - { java: 11, scala: 2.13.8 }
+          - { java: 11, scala: 2.13.18 }
           # TODO: enable this after it works!
-          # - { java: 11, scala: 3.1.2 }
+          # - { java: 11, scala: 3.3.5 }
 
     steps:
       - uses: actions/checkout@v4

.gitignore

@@ -18,3 +18,4 @@ TAGS
 metals.sbt
 .vscode
 .bsp
+.planning/

.jvmopts

@@ -4,5 +4,4 @@
 -XX:ReservedCodeCacheSize=250M
 -XX:+TieredCompilation
 -XX:-UseGCOverheadLimit
--XX:+CMSClassUnloadingEnabled
 

build.sbt

@@ -3,6 +3,7 @@ import sbt.{ Def, Global, Tags }
 
 import scala.collection.immutable.SortedSet
 import MonixBuildUtils._
+import org.typelevel.scalacoptions.ScalacOptions
 
 val benchmarkProjects = List(
   "benchmarksPrev",
@@ -31,9 +32,9 @@ val reactiveStreams_Version   = "1.0.4"
 val macrotaskExecutor_Version = "1.0.0"
 val minitest_Version          = "2.9.6"
 val implicitBox_Version       = "0.3.4"
-val kindProjector_Version     = "0.13.2"
+val kindProjector_Version     = "0.13.4"
 val betterMonadicFor_Version  = "0.3.1"
-val silencer_Version          = "1.7.8"
+val silencer_Version          = "1.7.19"
 val scalaCompat_Version       = "2.7.0"
 
 // The Monix version with which we must keep binary compatibility.
@@ -189,8 +190,19 @@ lazy val sharedSettings = pgpSettings ++ Seq(
     "-Wunused:explicits",
     "-Ywarn-unused:params",
     "-Wunused:params",
-    "-Xlint:infer-any"
+    "-Xlint:infer-any",
+    "-Wnonunit-statement"
   ),
+  // Disabled from tpolecat for test compilation:
+  // -Wunused:patvars triggers on for-comprehension loop vars in tests (pre-existing pattern)
+  // -Xlint:constant triggers on intentional overflow tests (e.g. Long.MaxValue + 1)
+  Test / scalacOptions --= {
+    CrossVersion.partialVersion(scalaVersion.value) match {
+      case Some((2, 13)) => Seq("-Wunused:patvars", "-Xlint:constant")
+      case Some((2, 12)) => Seq("-Ywarn-unused:patvars")
+      case _ => Seq.empty
+    }
+  },
   // Turning off fatal warnings for doc generation
   Compile / doc / tpolecatExcludeOptions ++= ScalacOptions.defaultConsoleExclude,
   // Silence everything in auto-generated files
@@ -202,7 +214,9 @@ lazy val sharedSettings = pgpSettings ++ Seq(
   },
   scalacOptions --= {
     if (isDotty.value)
-      Seq("-Xfatal-warnings")
+      // tpolecat uses -Werror in Scala 3; disable fatal warnings
+      // so that pre-existing value-discard and similar patterns don't break Scala 3 builds
+      Seq("-Werror")
     else
       Seq()
   },

monix-catnap/shared/src/test/scala/monix/execution/TypeClassLawsForCancelableFutureSuite.scala

@@ -33,7 +33,7 @@ object TypeClassLawsForCancelableFutureSuite extends BaseLawsSuite {
   }
 
   test("adaptError") {
-    implicit val ec = TestScheduler()
+    implicit val ec: TestScheduler = TestScheduler()
     val F = MonadError[CancelableFuture, Throwable]
 
     val fa1 = F.catchNonFatal(1); ec.tick()
@@ -45,7 +45,7 @@ object TypeClassLawsForCancelableFutureSuite extends BaseLawsSuite {
   }
 
   test("adaptErrorEval") {
-    implicit val ec = TestScheduler()
+    implicit val ec: TestScheduler = TestScheduler()
     val F = MonadError[CancelableFuture, Throwable]
 
     val fa1 = F.catchNonFatalEval(Eval.always(1)); ec.tick()
@@ -57,7 +57,7 @@ object TypeClassLawsForCancelableFutureSuite extends BaseLawsSuite {
   }
 
   test("flatMap should be stack safe") {
-    implicit val s = TestScheduler()
+    implicit val s: TestScheduler = TestScheduler()
     val n = 100000
     val M = Monad[CancelableFuture]
     val f = M.tailRecM(0)(i => M.pure(if (i < n) Left(i + 1) else Right(i)))

monix-eval/shared/src/test/scala/monix/eval/TypeClassLawsForTaskWithCallbackSuite.scala

@@ -51,7 +51,7 @@ class BaseTypeClassLawsForTaskWithCallbackSuite(implicit opts: Task.Options) ext
     implicit
     A: Eq[A],
     ec: TestScheduler,
-    opts: Options) = {
+    opts: Options): Eq[Task[A]] = {
 
     Eq.by { task =>
       val p = Promise[A]()

monix-reactive/js/src/main/scala/monix/reactive/observers/buffers/AbstractBackPressuredBufferedSubscriber.scala

@@ -17,10 +17,11 @@
 
 package monix.reactive.observers.buffers
 
-import monix.execution.Ack
+import monix.execution.{Ack, Scheduler}
 import monix.execution.Ack.{Continue, Stop}
 import monix.execution.internal.collection.JSArrayQueue
 import monix.execution.internal.math.nextPowerOf2
+
 import scala.util.control.NonFatal
 import monix.reactive.observers.{BufferedSubscriber, Subscriber}
 
@@ -37,7 +38,7 @@ private[observers] abstract class AbstractBackPressuredBufferedSubscriber[A, R](
   private[this] val bufferSize = nextPowerOf2(_size)
 
   private[this] val em = out.scheduler.executionModel
-  implicit final val scheduler = out.scheduler
+  implicit final val scheduler: Scheduler = out.scheduler
 
   private[this] var upstreamIsComplete = false
   private[this] var downstreamIsComplete = false

monix-reactive/js/src/main/scala/monix/reactive/observers/buffers/SyncBufferedSubscriber.scala

@@ -18,7 +18,7 @@
 package monix.reactive.observers.buffers
 
 import monix.eval.Coeval
-import monix.execution.Ack
+import monix.execution.{Ack, Scheduler}
 import monix.execution.Ack.{Continue, Stop}
 import monix.execution.internal.collection.{JSArrayQueue, _}
 
@@ -38,7 +38,7 @@ private[observers] final class SyncBufferedSubscriber[-A] private (
   onOverflow: Long => Coeval[Option[A]] = null)
   extends BufferedSubscriber[A] with Subscriber.Sync[A] {
 
-  implicit val scheduler = out.scheduler
+  implicit val scheduler: Scheduler = out.scheduler
   // to be modified only in onError, before upstreamIsComplete
   private[this] var errorThrown: Throwable = _
   // to be modified only in onError / onComplete

monix-reactive/jvm/src/main/scala/monix/reactive/compression/internal/operators/DeflateOperator.scala

@@ -18,8 +18,7 @@
 package monix.reactive.compression.internal.operators
 
 import java.util.zip.Deflater
-
-import monix.execution.Ack
+import monix.execution.{Ack, Scheduler}
 import monix.execution.Ack.Continue
 import monix.reactive.Observable.Operator
 import monix.reactive.compression.{CompressionLevel, CompressionParameters, CompressionStrategy, FlushMode}
@@ -36,7 +35,7 @@ private[compression] final class DeflateOperator(
 ) extends Operator[Array[Byte], Array[Byte]] {
   override def apply(out: Subscriber[Array[Byte]]): Subscriber[Array[Byte]] = {
     new Subscriber[Array[Byte]] {
-      implicit val scheduler = out.scheduler
+      implicit val scheduler: Scheduler = out.scheduler
 
       private[this] var ack: Future[Ack] = Continue
       private[this] val deflate =

monix-reactive/jvm/src/main/scala/monix/reactive/compression/internal/operators/GunzipOperator.scala

@@ -19,18 +19,11 @@ package monix.reactive.compression.internal.operators
 
 import java.util.zip.{CRC32, DataFormatException, Inflater}
 import java.{util => ju}
-
-import monix.execution.Ack
+import monix.execution.{Ack, Scheduler}
 import monix.execution.Ack.{Continue, Stop}
 import monix.reactive.Observable.Operator
 import monix.reactive.compression.internal.operators.Gunzipper._
-import monix.reactive.compression.{
-  gzipCompressionMethod,
-  gzipFlag,
-  gzipMagicFirstByte,
-  gzipMagicSecondByte,
-  CompressionException
-}
+import monix.reactive.compression.{CompressionException, gzipCompressionMethod, gzipFlag, gzipMagicFirstByte, gzipMagicSecondByte}
 import monix.reactive.observers.Subscriber
 
 import scala.annotation.tailrec
@@ -42,7 +35,7 @@ private[compression] final class GunzipOperator(bufferSize: Int) extends Operato
 
   def apply(out: Subscriber[Array[Byte]]): Subscriber[Array[Byte]] =
     new Subscriber[Array[Byte]] {
-      implicit val scheduler = out.scheduler
+      implicit val scheduler: Scheduler = out.scheduler
 
       private[this] var isDone = false
       private[this] var ack: Future[Ack] = _

monix-reactive/jvm/src/main/scala/monix/reactive/compression/internal/operators/GzipOperator.scala

@@ -20,23 +20,11 @@ package monix.reactive.compression.internal.operators
 import java.nio.charset.StandardCharsets
 import java.time.Instant
 import java.util.zip.{CRC32, Deflater}
-
-import monix.execution.Ack
+import monix.execution.{Ack, Scheduler}
 import monix.execution.Ack.Continue
 import monix.reactive.Observable.Operator
 import monix.reactive.compression.internal.operators.Gzipper.gzipOperatingSystem
-import monix.reactive.compression.{
-  gzipCompressionMethod,
-  gzipExtraFlag,
-  gzipFlag,
-  gzipMagicFirstByte,
-  gzipMagicSecondByte,
-  zeroByte,
-  CompressionLevel,
-  CompressionParameters,
-  CompressionStrategy,
-  FlushMode
-}
+import monix.reactive.compression.{CompressionLevel, CompressionParameters, CompressionStrategy, FlushMode, gzipCompressionMethod, gzipExtraFlag, gzipFlag, gzipMagicFirstByte, gzipMagicSecondByte, zeroByte}
 import monix.reactive.observers.Subscriber
 
 import scala.concurrent.Future
@@ -52,7 +40,7 @@ private[compression] final class GzipOperator(
 ) extends Operator[Array[Byte], Array[Byte]] {
   override def apply(out: Subscriber[Array[Byte]]): Subscriber[Array[Byte]] = {
     new Subscriber[Array[Byte]] {
-      implicit val scheduler = out.scheduler
+      implicit val scheduler: Scheduler = out.scheduler
 
       private[this] var ack: Future[Ack] = _
       private[this] val gzipper =

monix-reactive/jvm/src/main/scala/monix/reactive/compression/internal/operators/InflateOperator.scala

@@ -19,8 +19,7 @@ package monix.reactive.compression.internal.operators
 
 import java.util.zip.{DataFormatException, Inflater}
 import java.{util => ju}
-
-import monix.execution.Ack
+import monix.execution.{Ack, Scheduler}
 import monix.execution.Ack.{Continue, Stop}
 import monix.reactive.Observable.Operator
 import monix.reactive.compression.CompressionException
@@ -36,7 +35,7 @@ private[compression] final class InflateOperator(bufferSize: Int, noWrap: Boolea
 
   def apply(out: Subscriber[Array[Byte]]): Subscriber[Array[Byte]] =
     new Subscriber[Array[Byte]] {
-      implicit val scheduler = out.scheduler
+      implicit val scheduler: Scheduler = out.scheduler
 
       private[this] var isDone = false
       private[this] var ack: Future[Ack] = _

monix-reactive/jvm/src/main/scala/monix/reactive/observers/buffers/AbstractBackPressuredBufferedSubscriber.scala

@@ -17,14 +17,14 @@
 
 package monix.reactive.observers.buffers
 
-import monix.execution.{Ack, ChannelType}
+import monix.execution.{Ack, ChannelType, Scheduler}
 import monix.execution.Ack.{Continue, Stop}
 import monix.execution.BufferCapacity.Unbounded
 import monix.execution.ChannelType._
 import monix.execution.atomic.Atomic
 import monix.execution.atomic.PaddingStrategy.LeftRight256
 import monix.execution.internal.collection.LowLevelConcurrentQueue
-import monix.execution.internal.{math, Platform}
+import monix.execution.internal.{Platform, math}
 
 import scala.util.control.NonFatal
 import monix.reactive.observers.{BufferedSubscriber, Subscriber}
@@ -46,7 +46,7 @@ private[observers] abstract class AbstractBackPressuredBufferedSubscriber[A, R](
 
   private[this] val bufferSize = math.nextPowerOf2(_bufferSize)
   private[this] val em = out.scheduler.executionModel
-  implicit final val scheduler = out.scheduler
+  implicit final val scheduler: Scheduler = out.scheduler
 
   protected final val queue: LowLevelConcurrentQueue[A] =
     LowLevelConcurrentQueue(

monix-reactive/jvm/src/main/scala/monix/reactive/observers/buffers/DropNewBufferedSubscriber.scala

@@ -18,7 +18,7 @@
 package monix.reactive.observers.buffers
 
 import monix.eval.Coeval
-import monix.execution.Ack
+import monix.execution.{Ack, Scheduler}
 import monix.execution.Ack.{Continue, Stop}
 import monix.execution.atomic.PaddingStrategy.{LeftRight128, LeftRight256}
 import monix.execution.atomic.{Atomic, AtomicInt}
@@ -42,7 +42,7 @@ private[observers] final class DropNewBufferedSubscriber[A] private (
 
   require(bufferSize > 0, "bufferSize must be a strictly positive number")
 
-  implicit val scheduler = out.scheduler
+  implicit val scheduler: Scheduler = out.scheduler
   private[this] val em = out.scheduler.executionModel
 
   private[this] val itemsToPush =

monix-reactive/jvm/src/main/scala/monix/reactive/observers/buffers/EvictingBufferedSubscriber.scala

@@ -18,7 +18,7 @@
 package monix.reactive.observers.buffers
 
 import monix.eval.Coeval
-import monix.execution.Ack
+import monix.execution.{Ack, Scheduler}
 import monix.execution.Ack.{Continue, Stop}
 import monix.execution.atomic.PaddingStrategy.{LeftRight128, LeftRight256}
 import monix.execution.atomic.{Atomic, AtomicAny, AtomicInt}
@@ -112,7 +112,7 @@ private[observers] abstract class AbstractEvictingBufferedSubscriber[-A](
 
   require(strategy.bufferSize > 0, "bufferSize must be a strictly positive number")
 
-  implicit val scheduler = out.scheduler
+  implicit val scheduler: Scheduler = out.scheduler
   private[this] val em = out.scheduler.executionModel
 
   private[this] val droppedCount: AtomicInt =

monix-reactive/jvm/src/main/scala/monix/reactive/observers/buffers/SimpleBufferedSubscriber.scala

@@ -17,7 +17,7 @@
 
 package monix.reactive.observers.buffers
 
-import monix.execution.{Ack, ChannelType}
+import monix.execution.{Ack, ChannelType, Scheduler}
 import monix.execution.Ack.{Continue, Stop}
 import monix.execution.BufferCapacity.{Bounded, Unbounded}
 import monix.execution.ChannelType.SingleConsumer
@@ -62,7 +62,7 @@ private[observers] abstract class AbstractSimpleBufferedSubscriber[A] protected
 
   private[this] val queue = _qRef
   private[this] val em = out.scheduler.executionModel
-  implicit val scheduler = out.scheduler
+  implicit val scheduler: Scheduler = out.scheduler
   private[this] val itemsToPush =
     Atomic.withPadding(0, LeftRight256)
 

monix-reactive/shared/src/main/scala/monix/reactive/Observable.scala

@@ -365,7 +365,7 @@ abstract class Observable[+A] extends Serializable { self =>
     s: Scheduler): Cancelable = {
 
     subscribe(new Subscriber[A] {
-      implicit val scheduler = s
+      implicit val scheduler: Scheduler = s
 
       def onNext(elem: A) = nextFn(elem)
       def onComplete() = completedFn()