I might not be constructing the semantic db correctly here, I do not expect it to be empty.

Author: ShaneDelmore

examples/cross-rewrite-example/build/build.scala

@@ -7,7 +7,13 @@ import scalafix.util.TreePatch._
 import scalafix.util.TokenPatch._
 
 class Build(val context: Context) extends BaseBuild { outer =>
-  override def defaultScalaVersion = "2.12.1"
+  override def defaultScalaVersion = "2.11.8"
+
+  override def dependencies =
+    super.dependencies ++ // don't forget super.dependencies here
+      Resolver( mavenCentral ).bind(
+        ScalaDependency( "org.typelevel", "cats", "0.9.0" )
+      )
 
   override def test: Dependency = {
     new BasicBuild(context) with ScalaTest {
@@ -35,7 +41,7 @@ class Build(val context: Context) extends BaseBuild { outer =>
         //This works
         AddGlobalImport(importer"scalaz._"),
         //None of these work, why?
-        Replace(Symbol("_root_.scala.util.Either."), q"\/"),
+        Replace(Symbol("_root_.scala.package.Either."), q"\/"),
         Replace(Symbol("_root_.Disjunction."), q"Test"),
         Rename(q"intOrString", q"xor"),
         //And this works again.  What is different about import rewrites vs the others?

examples/cross-rewrite-example/src/Main.scala

@@ -1,4 +1,4 @@
-import scala.concurrent.Future
+import cats.implicits._
 
 object Main {
   def main(args: Array[String]): Unit = {

plugins/scalafix/Scalafix.scala

@@ -25,12 +25,16 @@ object Scalafix{
       patches: Seq[Patch] = Seq(),
       rewrites: Seq[ Rewrite[ScalafixMirror] ] = Seq(),
       allowEmpty: Boolean = false
-    ){
-      def mirror =
+    ) {
+      def mirror = {
+        println("creating semantic mirror")
+        println(s"classpath: ${classpath.string}")
+        println(s"files: ${files.map(_._1).mkString(File.pathSeparator)}")
         Mirror(
           classpath.string,
           files.map(_._1).mkString(File.pathSeparator)
         )
+      }
 
       def context(file: File): ( RewriteCtx[Mirror], RewriteCtx[ScalafixMirror] ) = (
         scalafix.rewrite.RewriteCtx(
@@ -46,19 +50,28 @@ object Scalafix{
           allowEmpty || rewrites.nonEmpty || patches.nonEmpty,
           "You need to provide some rewrites via: `override def scalafix = super.scalafix.copy( rewrites = Seq(...) )`"
         )
-        files.foreach{ case (from, to) =>
-          implicit val ( ctx, ctx2 ) = context(from)
-          lib.writeIfChanged(
-            to,
-            Patch(
-              (
-                patches
-                ++ rewrites.flatMap(
-                  _.rewrite( ctx2 ).to
-                )
-              ).to
+        files.foreach {
+          case (from, to) =>
+            implicit val (ctx, ctx2) = context(from)
+            println("printing sources")
+            println(ctx.mirror.sources)
+            println("printing database")
+            println(ctx.mirror.database)
+            println("printing mirror database messages")
+            println(ctx.mirror.database)
+            println("end printing")
+            assert(ctx.mirror.database.toString.trim != "", "I do not believe the database should be empty here")
+            lib.writeIfChanged(
+              to,
+              Patch(
+                (
+                  patches
+                    ++ rewrites.flatMap(
+                      _.rewrite(ctx2).to
+                    )
+                ).to
+              )
             )
-          )
         }
       }
     }