Setup scalafix

Author: OlivierBlanvillain

project/Build.scala

@@ -23,6 +23,7 @@ import sbtbuildinfo.BuildInfoPlugin
 import sbtbuildinfo.BuildInfoPlugin.autoImport._
 
 import scala.util.Properties.isJavaAtLeast
+import scalafix.sbt.ScalafixPlugin.autoImport._
 
 /* In sbt 0.13 the Build trait would expose all vals to the shell, where you
  * can use them in "set a := b" like expressions. This re-exposes them.
@@ -88,7 +89,6 @@ object Build {
   lazy val dotr =
     inputKey[Unit]("run compiled binary using the correct classpath, or the user supplied classpath")
 
-
   // Compiles the documentation and static site
   lazy val genDocs = taskKey[Unit]("run dottydoc to generate static documentation site")
 
@@ -114,10 +114,12 @@ object Build {
     organizationHomepage := Some(url("http://lamp.epfl.ch")),
 
     scalacOptions ++= Seq(
+      "-Yrangepos",
       "-feature",
       "-deprecation",
+      "-Ywarn-unused-import",
       "-unchecked",
-      "-Xfatal-warnings",
+      // "-Xfatal-warnings",
       "-encoding", "UTF8",
       "-language:existentials,higherKinds,implicitConversions"
     ),
@@ -745,7 +747,14 @@ object Build {
   def dottyCompilerSettings(implicit mode: Mode): sbt.Def.SettingsDefinition =
     if (mode == NonBootstrapped) nonBootstrapedDottyCompilerSettings else bootstrapedDottyCompilerSettings
 
-  lazy val `dotty-compiler` = project.in(file("compiler")).asDottyCompiler(NonBootstrapped)
+  lazy val `dotty-compiler` = project
+    .settings(addCompilerPlugin(scalafixSemanticdb))
+    .settings(scalafixDependencies in ThisBuild +=
+      // "com.geirsson" %% "example-scalafix-rule" % "1.3.0"
+      "com.twitter" %% "rsc-rules" % "0.0.0-406-6829ec44-20181004-1416"
+    )
+    .in(file("compiler")).asDottyCompiler(NonBootstrapped)
+
   lazy val `dotty-compiler-bootstrapped` = project.in(file("compiler")).asDottyCompiler(Bootstrapped)
 
   def dottyCompiler(implicit mode: Mode): Project = mode match {

project/plugins.sbt

@@ -16,3 +16,5 @@ addSbtPlugin("org.xerial.sbt" % "sbt-pack" % "0.10.1")
 addSbtPlugin("pl.project13.scala" % "sbt-jmh" % "0.3.2")
 
 addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.9.0")
+
+addSbtPlugin("ch.epfl.scala" % "sbt-scalafix" % "0.9.0")