Merge pull request scalacenter#2254 from eejbyfeldt/support-wall-in-remove-unused

Add -Wall as supported flag for RemoveUnused

Author: bjaglin

docs/rules/RemoveUnused.md

@@ -15,7 +15,7 @@ example diff from running `sbt "scalafix RemoveUnused"`.
 To use this rule:
 
 - Enable the Scala compiler option `-Ywarn-unused` (2.12), `-Wunused` (2.13),
-  or `-Wunused:all` (3.3.4+).
+  `-Wunused:all` (3.3.4+), or -Wall (with 3.5.2+ and backported to 3.3.5+).
 - Disable `-Xfatal-warnings` if you have it enabled. This is required so the
   compiler warnings do not fail the build before running Scalafix. If you are
   running 2.12.13+ or 2.13.2+, you may keep `-Xfatal-warnings` by modifying how

scalafix-rules/src/main/scala/scalafix/internal/rule/OrganizeImports.scala

@@ -870,7 +870,7 @@ object OrganizeImports {
 
     val hasWarnUnused = hasCompilerSupport && {
       val warnUnusedPrefix = Set("-Wunused", "-Ywarn-unused")
-      val warnUnusedString = Set("-Xlint", "-Xlint:unused")
+      val warnUnusedString = Set("-Wall", "-Xlint", "-Xlint:unused")
       scalacOptions exists { option =>
         (warnUnusedPrefix exists option.startsWith) || (warnUnusedString contains option)
       }

scalafix-rules/src/main/scala/scalafix/internal/rule/RemoveUnused.scala

@@ -30,7 +30,7 @@ class RemoveUnused(config: RemoveUnusedConfig)
   override def isRewrite: Boolean = true
 
   private def warnUnusedPrefix = List("-Wunused", "-Ywarn-unused")
-  private def warnUnusedString = List("-Xlint", "-Xlint:unused")
+  private def warnUnusedString = List("-Wall", "-Xlint", "-Xlint:unused")
   override def withConfiguration(config: Configuration): Configured[Rule] = {
     val diagnosticsAvailableInSemanticdb =
       Seq("3.0", "3.1", "3.2", "3.3.0", "3.3.1", "3.3.2", "3.3.3")
@@ -43,8 +43,8 @@ class RemoveUnused(config: RemoveUnusedConfig)
     if (!hasWarnUnused) {
       Configured.error(
         """|A Scala compiler option is required to use RemoveUnused. To fix this problem,
-          |update your build to add -Ywarn-unused (with 2.12), -Wunused (with 2.13), or 
-          |-Wunused:all (with 3.3.4+)""".stripMargin
+          |update your build to add -Ywarn-unused (with 2.12), -Wunused (with 2.13),
+          |-Wunused:all (with 3.3.4+), or -Wall (with 3.5.2+ and backported to 3.3.5+)""".stripMargin
       )
     } else if (!diagnosticsAvailableInSemanticdb) {
       Configured.error(