Merge pull request #10705 from som-snytt/tweak/lint-all

Lint all the things [ci: last-only]

build.sbt

@@ -160,16 +160,16 @@ lazy val commonSettings = instanceSettings ++ clearSourceAndResourceDirectories
   cleanFiles += (Compile / doc / target).value,
   run / fork := true,
   run / connectInput := true,
-  // uncomment for ease of development while breaking things
-  //Compile / scalacOptions ++= Seq("-Xmaxerrs", "5", "-Xmaxwarns", "5"),
-  // work around https://github.com/scala/bug/issues/11534
-  Compile / scalacOptions += "-Wconf:cat=unchecked&msg=The outer reference in this type test cannot be checked at run time.:s",
-  // we don't want optimizer warnings to interfere with `-Werror`. we have hundreds of such warnings
-  // when the optimizer is enabled (as it is in CI and release builds, though not in local development)
-  Compile / scalacOptions += "-Wconf:cat=optimizer:is",
-  // We use @nowarn for some methods that are deprecated in Java > 8
-  Compile / scalacOptions += "-Wconf:cat=unused-nowarn:s",
-  Compile / scalacOptions ++= Seq("-deprecation", "-feature"),
+  Compile / scalacOptions ++= Seq("-feature", "-Xlint",
+    //"-Xmaxerrs", "5", "-Xmaxwarns", "5", // uncomment for ease of development while breaking things
+    // work around https://github.com/scala/bug/issues/11534
+    "-Wconf:cat=unchecked&msg=The outer reference in this type test cannot be checked at run time.:s",
+    // optimizer warnings at INFO since `-Werror` may be turned on.
+    // optimizer runs in CI and release builds, though not in local development.
+    "-Wconf:cat=optimizer:is",
+    // we use @nowarn for methods that are deprecated in JDK > 8, but CI/release is under JDK 8
+    "-Wconf:cat=unused-nowarn:s",
+    ),
   Compile / doc / scalacOptions ++= Seq(
     "-doc-footer", "epfl",
     "-diagrams",
@@ -412,7 +412,6 @@ lazy val library = configureAsSubproject(project)
     name := "scala-library",
     description := "Scala Standard Library",
     Compile / scalacOptions ++= Seq("-sourcepath", (Compile / scalaSource).value.toString),
-    Compile / scalacOptions ++= Seq("-Xlint", "-feature"),
     Compile / doc / scalacOptions ++= {
       val libraryAuxDir = (ThisBuild / baseDirectory).value / "src/library-aux"
       Seq(
@@ -460,7 +459,6 @@ lazy val reflect = configureAsSubproject(project)
     name := "scala-reflect",
     description := "Scala Reflection Library",
     Osgi.bundleName := "Scala Reflect",
-    Compile / scalacOptions ++= Seq("-Xlint", "-feature"),
     Compile / doc / scalacOptions ++= Seq(
       "-skip-packages", "scala.reflect.macros.internal:scala.reflect.internal:scala.reflect.io"
     ),
@@ -532,8 +530,6 @@ lazy val compiler = configureAsSubproject(project)
       ).get
     },
     Compile / scalacOptions ++= Seq(
-      "-Xlint",
-      "-feature",
       "-Wconf:cat=deprecation&msg=early initializers:s", // compiler heavily relies upon early initializers
     ),
     Compile / doc / scalacOptions ++= Seq(
@@ -574,15 +570,15 @@ lazy val interactive = configureAsSubproject(project)
   .settings(
     name := "scala-compiler-interactive",
     description := "Scala Interactive Compiler",
-    Compile / scalacOptions ++= Seq("-Xlint", "-Wconf:cat=deprecation&msg=early initializers:s"),
+    Compile / scalacOptions ++= Seq("-Wconf:cat=deprecation&msg=early initializers:s"),
   )
   .dependsOn(compiler)
 
 lazy val repl = configureAsSubproject(project)
   .settings(disableDocs)
   .settings(fatalWarningsSettings)
   .settings(publish / skip := true)
-  .settings(Compile / scalacOptions ++= Seq("-Xlint", "-Wconf:cat=deprecation&msg=early initializers:s"))
+  .settings(Compile / scalacOptions ++= Seq("-Wconf:cat=deprecation&msg=early initializers:s"))
   .dependsOn(compiler, interactive)
 
 lazy val replFrontend = configureAsSubproject(project, srcdir = Some("repl-frontend"))
@@ -592,7 +588,6 @@ lazy val replFrontend = configureAsSubproject(project, srcdir = Some("repl-front
   .settings(
     libraryDependencies ++= jlineDeps,
     name := "scala-repl-frontend",
-    Compile / scalacOptions ++= Seq("-Xlint"),
   )
   .settings(
     run := (Compile / run).partialInput(" -usejavacp").evaluated, // so `replFrontend/run` works
@@ -612,8 +607,6 @@ lazy val scaladoc = configureAsSubproject(project)
     libraryDependencies ++= ScaladocSettings.webjarResources,
     Compile / resourceGenerators += ScaladocSettings.extractResourcesFromWebjar,
     Compile / scalacOptions ++= Seq(
-      "-Xlint",
-      "-feature",
       "-Wconf:cat=deprecation&msg=early initializers:s",
     ),
   )
@@ -629,8 +622,6 @@ lazy val sbtBridge = configureAsSubproject(project, srcdir = Some("sbt-bridge"))
     description := "sbt compiler bridge for Scala 2",
     libraryDependencies += compilerInterfaceDep % Provided,
     Compile / scalacOptions ++= Seq(
-      "-Xlint",
-      "-feature",
       "-Wconf:cat=deprecation&msg=early initializers:s", // compiler heavily relies upon early initializers
     ),
     generateServiceProviderResources("xsbti.compile.CompilerInterface2" -> "scala.tools.xsbt.CompilerBridge"),
@@ -687,7 +678,6 @@ lazy val scalap = configureAsSubproject(project)
       xs filter { x => !excluded(x.getName) }
     },
     Compile / headerResources := Nil,
-    Compile / scalacOptions ++= Seq("-Xlint", "-feature"),
   )
   .dependsOn(compiler)
 
@@ -702,7 +692,6 @@ lazy val partest = configureAsSubproject(project)
     libraryDependencies ++= List(testInterfaceDep, diffUtilsDep, junitDep),
     Compile / javacOptions ++= Seq("-XDenableSunApiLintControl", "-Xlint") ++
       (if (fatalWarnings.value) Seq("-Werror") else Seq()),
-    Compile / scalacOptions ++= Seq("-feature", "-Xlint"),
     pomDependencyExclusions ++= List((organization.value, "scala-repl-frontend"), (organization.value, "scala-compiler-doc")),
     fixPom(
       "/project/name" -> <name>Scala Partest</name>,
@@ -720,7 +709,6 @@ lazy val tastytest = configureAsSubproject(project)
     name := "scala-tastytest",
     description := "Scala TASTy Integration Testing Tool",
     libraryDependencies += diffUtilsDep,
-    Compile / scalacOptions ++= Seq("-feature", "-Xlint"),
   )
 
 // An instrumented version of BoxesRunTime and ScalaRunTime for partest's "specialized" test category
@@ -752,7 +740,6 @@ lazy val specLib = project.in(file("test") / "instrumented")
         patch("ScalaRunTime.scala", "srt.patch")
       )
     }.taskValue,
-    Compile / scalacOptions ++= Seq("-feature", "-Xlint"),
   )
 
 // The scala version used by the benchmark suites, leave undefined to use the ambient version.")
@@ -790,7 +777,6 @@ lazy val testkit = configureAsSubproject(project)
   .settings(
     name := "scala-testkit",
     description := "Scala Compiler Testkit",
-    Compile / scalacOptions ++= Seq("-feature", "-Xlint"),
     libraryDependencies ++= Seq(junitDep, asmDep),
     Compile / unmanagedSourceDirectories := List(baseDirectory.value),
     fixPom(
@@ -819,8 +805,7 @@ lazy val junit = project.in(file("test") / "junit")
     (Test / forkOptions) := (Test / forkOptions).value.withWorkingDirectory((ThisBuild / baseDirectory).value),
     (Test / testOnly / forkOptions) := (Test / testOnly / forkOptions).value.withWorkingDirectory((ThisBuild / baseDirectory).value),
     Compile / scalacOptions ++= Seq(
-      "-feature",
-      "-Xlint:-valpattern,_",
+      "-Xlint:-valpattern",
       "-Wconf:msg=match may not be exhaustive:s", // if we missed a case, all that happens is the test fails
       "-Wconf:cat=lint-nullary-unit&site=.*Test:s", // normal unit test style
       "-Ypatmat-exhaust-depth", "40", // despite not caring about patmat exhaustiveness, we still get warnings for this
@@ -869,6 +854,9 @@ lazy val tasty = project.in(file("test") / "tasty")
         s"-Dtastytest.classpaths.scalaReflect=$scalaReflect",
       )
     },
+    Compile / scalacOptions ++= Seq(
+      "-Wconf:cat=lint-nullary-unit&site=.*Test:s", // normal unit test style
+    ),
   )
 
 lazy val scalacheck = project.in(file("test") / "scalacheck")
@@ -889,7 +877,11 @@ lazy val scalacheck = project.in(file("test") / "scalacheck")
     ),
     libraryDependencies ++= Seq(scalacheckDep, junitDep),
     Compile / unmanagedSourceDirectories := Nil,
-    Test / unmanagedSourceDirectories := List(baseDirectory.value)
+    Test / unmanagedSourceDirectories := List(baseDirectory.value),
+    Compile / scalacOptions ++= Seq(
+      "-Wconf:msg=match may not be exhaustive:s", // if we missed a case, all that happens is the test fails
+      "-Wconf:msg=Classes which cannot access Tree:s", // extension is irrelevant to tests
+    ),
   )
 
 lazy val osgiTestFelix = osgiTestProject(

src/manual/scala/tools/docutil/ManMaker.scala

@@ -57,7 +57,7 @@ class ManMaker {
 
 /** Command line runner for ManMaker which is called from the sbt build. */
 object ManMaker extends App {
-  val Array(commands, htmlout, manout) = args
+  val Array(commands, htmlout, manout) = args: @unchecked
   val mm = new ManMaker
   mm.setCommand(commands)
   mm.setHtmlout(new File(htmlout))

src/partest/scala/tools/partest/nest/FromString.scala

@@ -13,8 +13,6 @@
 package scala.tools.partest.nest
 
 import scala.reflect.OptManifest
-import scala.sys.process.Parser.tokenize
-import scala.tools.nsc.io.Directory
 
 /** A general mechanism for defining how a command line argument
  *  (always a String) is transformed into an arbitrary type.  A few
@@ -30,6 +28,8 @@ abstract class FromString[+T](implicit m: OptManifest[T]) extends PartialFunctio
 }
 
 object FromString {
+  import scala.sys.process.Parser.tokenize
+  import scala.tools.nsc.io.Directory
   // We need this because we clash with the String => Path implicits.
   private def toDir(s: String)  = new Directory(new java.io.File(s))
 
@@ -66,6 +66,6 @@ object FromString {
    */
   implicit val IntFromString: FromString[Int] = new FromString[Int] {
     override def isDefinedAt(s: String)   = s.toIntOption.isDefined
-    def apply(s: String)                  = s.toInt
+    def apply(s: String)                  = s.toIntOption.getOrElse(0)
   }
 }

test/osgi/src/BasicLibrary.scala

@@ -2,18 +2,13 @@ package tools.test.osgi
 package libonly
 
 import org.junit.Assert._
-import org.ops4j.pax.exam.CoreOptions._
 
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.ops4j.pax.exam
 import org.ops4j.pax.exam.Configuration
 import org.ops4j.pax.exam.junit.PaxExam
 import org.ops4j.pax.exam.spi.reactors.{ ExamReactorStrategy, PerMethod }
-import org.ops4j.pax.swissbox.tracker.ServiceLookup
-import org.osgi.framework.BundleContext
-
-
 
 @RunWith(classOf[PaxExam])
 @ExamReactorStrategy(Array(classOf[PerMethod]))

test/osgi/src/BasicReflection.scala

@@ -2,20 +2,14 @@ package tools.test.osgi
 package reflection
 package basic
 
-import scala.language.higherKinds
-
 import org.junit.Assert._
-import org.ops4j.pax.exam.CoreOptions._
 
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.ops4j.pax.exam
 import org.ops4j.pax.exam.Configuration
 import org.ops4j.pax.exam.junit.PaxExam
 import org.ops4j.pax.exam.spi.reactors.{ ExamReactorStrategy, PerMethod }
-import org.ops4j.pax.swissbox.tracker.ServiceLookup
-import org.osgi.framework.BundleContext
-
 
 class C {
   val f1 = 2

test/osgi/src/BasicTest.scala

@@ -1,20 +1,11 @@
 package tools.test.osgi
 
-import org.junit.Assert._
-import org.ops4j.pax.exam.CoreOptions._
-
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.ops4j.pax.exam
 import org.ops4j.pax.exam.Configuration
 import org.ops4j.pax.exam.junit.PaxExam
 import org.ops4j.pax.exam.spi.reactors.{ ExamReactorStrategy, PerMethod }
-import org.ops4j.pax.swissbox.tracker.ServiceLookup
-import org.osgi.framework.BundleContext
-
-
-
-
 
 @RunWith(classOf[PaxExam])
 @ExamReactorStrategy(Array(classOf[PerMethod]))

test/osgi/src/ReflectionToolboxTest.scala

@@ -3,17 +3,13 @@ package reflection
 package toolbox
 
 import org.junit.Assert._
-import org.ops4j.pax.exam.CoreOptions._
 
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.ops4j.pax.exam
 import org.ops4j.pax.exam.Configuration
 import org.ops4j.pax.exam.junit.PaxExam
 import org.ops4j.pax.exam.spi.reactors.{ ExamReactorStrategy, PerMethod }
-import org.ops4j.pax.swissbox.tracker.ServiceLookup
-import org.osgi.framework.BundleContext
-
 
 class C {
   val f1 = 2
@@ -35,6 +31,7 @@ class ReflectionToolBoxTest extends ScalaOsgiHelper {
     import scala.tools.reflect.ToolBox
     val cm = runtimeMirror(classOf[C].getClassLoader)
     val tb = cm.mkToolBox()
+    @annotation.unused
     val im = cm.reflect(new C)
     val tree = tb.parse("1 to 3 map (_+1)")
     val eval = tb.eval(tree)

test/scalacheck/CheckEither.scala

@@ -1,9 +1,7 @@
-import org.scalacheck.{ Arbitrary, Prop, Properties }
+import org.scalacheck.{Arbitrary, Properties}
 import org.scalacheck.Arbitrary.{arbitrary, arbThrowable}
 import org.scalacheck.Gen.oneOf
 import org.scalacheck.Prop._
-import org.scalacheck.Test.check
-import Function.tupled
 import scala.util.Either.LeftProjection
 
 @annotation.nowarn("cat=deprecation")

test/scalacheck/Ctrie.scala

@@ -5,6 +5,8 @@ import collection._
 import collection.concurrent.TrieMap
 import scala.language.reflectiveCalls
 
+import annotation.unused
+
 case class Wrap(i: Int) {
   override def hashCode = i // * 0x9e3775cd
 }
@@ -101,7 +103,7 @@ object CtrieTest extends Properties("concurrent.TrieMap") {
     val ct = new TrieMap[Wrap, Int]
 
     // checker
-    val checker = spawn {
+    @unused val checker = spawn {
       def check(last: Map[Wrap, Int], iterationsLeft: Int): Boolean = {
         val current = ct.readOnlySnapshot()
         if (!hasGrown(last, current)) false
@@ -187,7 +189,7 @@ object CtrieTest extends Properties("concurrent.TrieMap") {
     val totalInserts = new java.util.concurrent.atomic.AtomicInteger
     val ct = new TrieMap[Wrap, String]
 
-    val results = inParallel(p) {
+    @unused val results = inParallel(p) {
       idx =>
       (0 until sz) foreach {
         i =>

test/scalacheck/SeqMap.scala

@@ -5,8 +5,6 @@ import Arbitrary.arbitrary
 import Prop._
 import Gen._
 
-import scala.collection.mutable.ListBuffer
-
 object SeqMapTest extends Properties("SeqMap") {
 
   property("overrides stringPrefix") = {

test/scalacheck/array-new.scala

@@ -5,7 +5,6 @@ import Gen._
 import Arbitrary._
 import util._
 import Buildable._
-import scala.collection.mutable.ArraySeq
 
 object ArrayNewTest extends Properties("Array") {
   /** At this moment the authentic scalacheck Array Builder/Arb bits are commented out.

test/scalacheck/array-old.scala

@@ -4,7 +4,6 @@ import Gen._
 import Arbitrary._
 import util._
 import Buildable._
-import scala.collection.mutable.ArraySeq
 
 object ArrayOldTest extends Properties("Array") {
   /** At this moment the authentic scalacheck Array Builder/Arb bits are commented out.

test/scalacheck/primitive-eqeq.scala

@@ -15,7 +15,7 @@ object PrimitiveEqEqTest extends Properties("==") {
   property("transitivity") = forAll { (x: AnyVal, y: AnyVal, z: AnyVal) => x != y || y != z || x == z }
 
   property("##") = forAll { x: Short =>
-    val anyvals = List(x.toByte, x.toChar, x, x.toInt, x.toLong, x.toFloat, x.toDouble, BigInt(x), BigDecimal(x))
+    val anyvals = List[Any](x.toByte, x.toChar, x, x.toInt, x.toLong, x.toFloat, x.toDouble, BigInt(x), BigDecimal(x))
     val shortAndLarger = anyvals drop 2
 
     (anyvals.lazyZip(anyvals) forall equalObjectsEqualHashcodes) &&

test/scalacheck/range.scala

@@ -104,7 +104,6 @@ abstract class RangeTest(kind: String) extends Properties("Range "+kind) {
   property("foreach.inside.range") = forAll(myGen) { r =>
 //    println("foreach.inside.range "+str(r))
     var allValid = true
-    var last: Option[Int] = None
     val cnt = new Counter(r)
     r foreach { x => cnt(x)
       allValid &&= within(r, x)