Rewrite retain to filterInPlace (fix scala/collection-strawman #556)

Author: MasseGuillaume

scalafix/build.sbt

@@ -37,7 +37,8 @@ lazy val tests = project
         sourceDirectory.in(output, Compile).value,
       "inputClassdirectory" ->
         classDirectory.in(input, Compile).value
-    )
+    ),
+    test in Test := (test in Test).dependsOn(compile in (output, Compile)).value
   )
   .dependsOn(input, rules)
   .enablePlugins(BuildInfoPlugin)

scalafix/input/src/main/scala/fix/MethodRenames.scala

@@ -0,0 +1,10 @@
+/*
+rule = "scala:fix.Scalacollectioncompat_NewCollections"
+ */
+package fix
+
+import scala.collection.mutable.Map
+
+object MethodRenames {
+  Map(1 -> 1).retain{ case (x, y) => true }
+}

scalafix/output/src/main/scala/fix/MethodRenames.scala

@@ -0,0 +1,7 @@
+package fix
+
+import scala.collection.mutable.Map
+
+object MethodRenames {
+  Map(1 -> 1).filterInPlace{ case (x, y) => true }
+}

scalafix/rules/src/main/scala/fix/Scalacollectioncompat_NewCollections.scala

@@ -30,6 +30,17 @@ case class Scalacollectioncompat_NewCollections(index: SemanticdbIndex)
     Symbol("_root_.scala.runtime.Tuple3Zipped.Ops.zipped.")
   )
 
+  val retain = 
+    SymbolMatcher.normalized(
+      Symbol("_root_.scala.collection.mutable.MapLike.retain.")
+    )
+
+  def replaceMutableMap(ctx: RuleCtx) =
+    ctx.tree.collect {
+      case retain(t: Name) =>
+        ctx.replaceTree(t, "filterInPlace")
+    }.asPatch
+
   def replaceToList(ctx: RuleCtx) =
     ctx.tree.collect {
       case iterator(t: Name) =>
@@ -110,6 +121,7 @@ case class Scalacollectioncompat_NewCollections(index: SemanticdbIndex)
       replaceSymbols(ctx) +
       replaceTupleZipped(ctx) +
       replaceCopyToBuffer(ctx) +
-      replaceStreamAppend(ctx)
+      replaceStreamAppend(ctx) +
+      replaceMutableMap(ctx)
   }
 }