address more warnings

build.sbt

@@ -193,7 +193,6 @@ val completeProj = (project in file("internal") / "util-complete")
     testedBaseSettings,
     name := "Completion",
     libraryDependencies += jline,
-    Compile / scalacOptions += "-Ywarn-unused:-explicits",
     mimaSettings,
     // Parser is used publicly, so we can't break bincompat.
     mimaBinaryIssueFilters := Seq(

core-macros/src/main/scala/sbt/internal/util/appmacro/Instance.scala

@@ -67,7 +67,7 @@ object Instance {
    *
    * Each `input` in each expression of the form `wrap[T]( input )` is transformed by `convert`.
    * This transformation converts the input Tree to a Tree of type `M[T]`.
-   * The original wrapped expression `wrap(input)` is replaced by a reference to a new local `val $x: T`, where `$x` is a fresh name.
+   * The original wrapped expression `wrap(input)` is replaced by a reference to a new local `val x: T`, where `x` is a fresh name.
    * These converted inputs are passed to `builder` as well as the list of these synthetic `ValDef`s.
    * The `TupleBuilder` instance constructs a tuple (Tree) from the inputs and defines the right hand side of the vals
    * that unpacks the tuple containing the results of the inputs.

internal/util-complete/src/main/scala/sbt/internal/util/complete/ExampleSource.scala

@@ -13,7 +13,7 @@ import sbt.io.IO
 
 /**
  * These sources of examples are used in parsers for user input completion. An example of such a source is the
- * [[sbt.complete.FileExamples]] class, which provides a list of suggested files to the user as they press the
+ * [[sbt.internal.util.complete.FileExamples]] class, which provides a list of suggested files to the user as they press the
  * TAB key in the console.
  */
 trait ExampleSource {

internal/util-logic/src/main/scala/sbt/internal/util/logic/Logic.scala

@@ -42,7 +42,7 @@ final case class Clauses(clauses: List[Clause]) {
 /** When the `body` Formula succeeds, atoms in `head` are true. */
 final case class Clause(body: Formula, head: Set[Atom])
 
-/** A literal is an [[Atom]] or its [[negation|Negated]]. */
+/** A literal is an [[Atom]] or its negation ([[Negated]]). */
 sealed abstract class Literal extends Formula {
 
   /** The underlying (positive) atom. */

main-settings/src/main/scala/sbt/Structure.scala

@@ -280,13 +280,13 @@ object Scoped {
     final def set(app: Initialize[S], source: SourcePosition): Setting[S] =
       setting(scopedKey, app, source)
 
-    /** From the given [[Settings]], extract the value bound to this key. */
+    /** From the given `Settings`, extract the value bound to this key. */
     final def get(settings: Settings[Scope]): Option[S] =
       settings.get(scopedKey.scope, scopedKey.key)
 
     /**
-     * Creates an [[Def.Initialize]] with value [[scala.None]] if there was no previous definition of this key,
-     * and `[[scala.Some]](value)` if a definition exists. Useful for when you want to use the ''existence'' of
+     * Creates an [[Def.Initialize]] with value `scala.None` if there was no previous definition of this key,
+     * and `scala.Some(value)` if a definition exists. Useful for when you want to use the ''existence'' of
      * one setting in order to define another setting.
      * @return currently bound value wrapped in `Initialize[Some[T]]`, or `Initialize[None]` if unbound.
      */

project/Util.scala

@@ -25,25 +25,14 @@ object Util {
   )
 
   lazy val baseScalacOptions = Seq(
-    scalacOptions ++= Seq("-Xelide-below", "0"),
     scalacOptions ++= Seq(
-      "-encoding",
-      "utf8",
-      "-deprecation",
-      "-feature",
-      "-unchecked",
-      "-Xlint",
+      "-Xelide-below",
+      "0",
       "-language:existentials",
-      "-language:higherKinds",
-      "-language:implicitConversions",
       "-language:postfixOps",
-      "-Xfuture",
-      "-Yno-adapted-args",
-      "-Ywarn-dead-code",
-      "-Ywarn-numeric-widen",
-      "-Ywarn-unused:-patvars,-implicits,_",
-      "-Ywarn-unused-import"
-    )
+    ),
+    Compile / doc / scalacOptions -= "-Xlint",
+    Compile / doc / scalacOptions -= "-Xfatal-warnings",
   )
 
   def projectComponent: Setting[_] =

tasks/src/main/scala/sbt/ConcurrentRestrictions.scala

@@ -142,7 +142,7 @@ object ConcurrentRestrictions {
       warn: String => Unit
   ): CompletionService[A, R] = {
 
-    /** Represents submitted work for a task.*/
+    // Represents submitted work for a task.
     final class Enqueue(val node: A, val work: () => R)
 
     new CompletionService[A, R] {

tasks/src/main/scala/sbt/Execute.scala

@@ -215,7 +215,7 @@ private[sbt] final class Execute[A[_] <: AnyRef](
       node,
       deps,
       active.toList
-      /** active is mutable, so take a snapshot */
+      /* active is mutable, so take a snapshot */
     )
 
     if (active.isEmpty)

testing/src/main/scala/sbt/JUnitXmlTestsListener.scala

@@ -98,7 +98,7 @@ class JUnitXmlTestsListener(val outputDir: String, logger: Logger) extends Tests
 
       val (errors, failures, tests) = (count(TStatus.Error), count(TStatus.Failure), events.size)
 
-      /** Junit XML reports don't differentiate between ignored, skipped or pending tests */
+      // Junit XML reports don't differentiate between ignored, skipped or pending tests
       val ignoredSkippedPending = count(TStatus.Ignored) + count(TStatus.Skipped) + count(
         TStatus.Pending
       )