Almost complete with rewrite.

Blocked by

- scalameta/scalameta#1037
- scalacenter/scalafix#252
- scalacenter/scalafix#253

Author: olafurpg

build.sbt

@@ -1,3 +1,4 @@
+def scalafixVersion = _root_.scalafix.Versions.version
 // Use a scala version supported by scalafix.
 scalaVersion in ThisBuild := org.scalameta.BuildInfo.supportedScalaVersions.last
 
@@ -6,7 +7,7 @@ lazy val root = project
   .aggregate(rewrites, input, output, tests)
 
 lazy val rewrites = project.settings(
-  libraryDependencies += "ch.epfl.scala" %% "scalafix-core" % "0.4.2"
+  libraryDependencies += "ch.epfl.scala" %% "scalafix-core" % scalafixVersion
 )
 
 lazy val input = project.settings(
@@ -27,7 +28,7 @@ lazy val output = project
 
 lazy val tests = project
   .settings(
-    libraryDependencies += "ch.epfl.scala" % "scalafix-testkit" % "0.4.2" % Test cross CrossVersion.full,
+    libraryDependencies += "ch.epfl.scala" % "scalafix-testkit" % scalafixVersion % Test cross CrossVersion.full,
     buildInfoPackage := "fix",
     buildInfoKeys := Seq[BuildInfoKey](
       "inputSourceroot" ->

input/src/main/scala/fix/Collectionstrawman_v0.scala

@@ -1,5 +1,25 @@
 /* ONLY
 rewrite = "scala:fix.Collectionstrawman_v0"
+patches.moveSymbols = [
+  { from = "scala.collection.immutable.HashMap",
+    to   = "strawman.collection.immutable.HashMap" }
+  { from = "scala.collection.immutable.Map",
+    to   = "strawman.collection.immutable.Map" }
+  { from = "scala.Predef.Map",
+    to   = "strawman.collection.immutable.Map" }
+  { from = "scala.collection.immutable.List",
+    to   = "strawman.collection.immutable.List" }
+  { from = "scala.collection.immutable.Nil",
+    to   = "strawman.collection.immutable.Nil" }
+  { from = "scala.package.Stream",
+    to   = "strawman.collection.immutable.LazyList" }
+  { from = "scala.package.`#::`",
+    to   = "strawman.collection.immutable.LazyList.`#::`" }
+  { from = "scala.package.Vector",
+    to   = "strawman.collection.immutable.Vector" }
+  { from = "scala.collection.mutable.ArrayBuffer",
+    to   = "strawman.collection.mutable.ArrayBuffer" }
+]
 */
 package fix
 

output/src/main/scala/fix/Collectionstrawman_v0.scala

@@ -34,12 +34,10 @@ object Collectionstrawman_v0_Seq {
 
 object Collectionstrawman_v0_Map {
   val xs: Map[Int, String] = Map(1 -> "1", 2 -> "2", 3 -> "3")
-  import strawman.collection.immutable.HashMap
   val ys = HashMap.empty
 }
 
 object Collectionstrawman_v0_ArrayBuffer {
-  import strawman.collection.mutable.ArrayBuffer
   val xs: ArrayBuffer[Int] = ArrayBuffer(1, 2, 3)
 }
 

project/plugins.sbt

@@ -1,5 +1,4 @@
-addSbtPlugin("ch.epfl.scala" % "sbt-scalafix" % "0.4.2")
-addSbtPlugin("ch.epfl.scala" % "sbt-scalafix" % "0.4.2")
-addSbtPlugin("io.get-coursier" % "sbt-coursier" % "1.0.0-RC3")
+addSbtPlugin("ch.epfl.scala" % "sbt-scalafix" % "0.5.0-M1")
+addSbtPlugin("io.get-coursier" % "sbt-coursier" % "1.0.0-RC6")
 addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.6.1")
 

rewrites/src/main/scala/fix/Collectionstrawman_v0.scala

@@ -1,16 +1,69 @@
 package fix
+// scalafmt: { maxColumn = 120 }
 
 import scalafix._
+import scalafix.syntax._
+import scalafix.internal.util.SymbolOps
 import scala.meta._
 
-case class Collectionstrawman_v0(mirror: Mirror)
-    extends SemanticRewrite(mirror) {
+case class Collectionstrawman_v0(mirror: Mirror) extends SemanticRewrite(mirror) {
   val immutableListSymbol = Symbol("_root_.scala.collection.immutable.List.")
+  val unimports = Set(
+    Symbol("_root_.scala.List."),
+    Symbol("_root_.scala.Seq."),
+    Symbol("_root_.scala.Vector."),
+    Symbol("_root_.scala.`::`."),
+    Symbol("_root_.scala.`#::`."),
+    Symbol("_root_.scala.Predef.Map."),
+    Symbol("_root_.scala.Predef.intArrayOps."),
+    Symbol("_root_.scala.Predef.augmentString."),
+    Symbol("_root_.scala.Predef.intArrayOps.")
+  )
+
+  def normalize(symbol: Symbol): Symbol = {
+    def loop(symbol: Symbol): Symbol = symbol match {
+      case Symbol.Global(qual, Signature.Term("package")) => loop(qual)
+      case Symbol.Global(qual, name)                      => Symbol.Global(loop(qual), name)
+      case x                                              => x
+    }
+    loop(symbol.normalized)
+  }
+
+  def ifSymbolFound(ctx: RewriteCtx): Patch = {
+    val toUnimport = ctx.mirror.database.names.flatMap {
+      case (_, sym) =>
+        val norm = normalize(sym)
+        if (unimports.contains(norm)) norm :: Nil
+        else Nil
+    }
+    val unimportss = toUnimport.toList.distinct.flatMap { sym =>
+      SymbolOps.toImporter(sym).toList.collect {
+        case Importer(qual, Importee.Name(n) :: Nil) =>
+          Importer(qual, Importee.Unimport(n) :: Nil)
+      }
+    }
+    val grouped = unimportss.groupBy(_.ref.syntax).collect {
+      case (qual, iss @ is :: _) =>
+        val names = iss.collect { case Importer(_, name :: Nil) => name }
+        Importer(is.ref, names)
+    }
+    grouped.map(ctx.addGlobalImport(_)).asPatch
+  }
+
+//  def isSymbol(tree: Tree, symbol: Symbol): Boolean = {
+//    mirror.database.names.get(tree.pos).exists(normalize(_) == symbol)
+//  }
+
+  def rangePatch(ctx: RewriteCtx): Patch = {
+//    ctx.tree.collect {
+//      case q"$lhs $op $rhs" if isSymbol(op, Symbol()) =>
+//        op
+//    }
+    Patch.empty
+  }
+
   def rewrite(ctx: RewriteCtx): Patch = {
-    ctx.tree.collect {
-      case name @ Term.Name(_) if name.symbol == immutableListSymbol =>
-        ctx.addGlobalImport(importer"scala.{List => _}") +
-          ctx.addGlobalImport(importer"strawman.collection.immutable.List")
-    }.asPatch
+    ctx.debugMirror()
+    ifSymbolFound(ctx)
   }
 }

tests/src/test/scala/fix/Collectionstrawman_Tests.scala

@@ -9,5 +9,9 @@ class Collectionstrawman_Tests
     AbsolutePath(BuildInfo.inputSourceroot),
     Seq(AbsolutePath(BuildInfo.outputSourceroot))
   ) {
+  override def assertNoDiff(a: String, b: String, c: String) = {
+    println(a)
+    super.assertNoDiff(a, b, c)
+  }
   runAllTests()
 }