WIP unit3 to show code, not working

This is the commit message scalacenter#2:

unit3 munit dep: exclude 2.13 and include munit_3 instead

build.sbt

@@ -101,7 +101,9 @@ lazy val rules = projectMatrix
           semanticdbScalacCore,
           collectionCompat
         )
-      else Nil
+      else List(
+        // ("org.scalameta" % "semanticdb-scalac-core" % scalametaV cross CrossVersion.for3Use2_13)
+      )
     }
   )
   .defaultAxes(VirtualAxis.jvm)
@@ -211,10 +213,7 @@ lazy val testkit = projectMatrix
     isFullCrossVersion,
     libraryDependencies += googleDiff,
     libraryDependencies ++= {
-      if (!isScala3.value)
-        Seq(scalatest)
-      else
-        Seq("org.scalatest" %% "scalatest" % scalatest3V)
+      scalatestDeps.value
     }
   )
   .defaultAxes(VirtualAxis.jvm)
@@ -231,14 +230,26 @@ lazy val unit = projectMatrix
     testFrameworks += new TestFramework("munit.Framework"),
     buildInfoPackage := "scalafix.tests",
     buildInfoObject := "BuildInfo",
-    libraryDependencies ++= List(
-      jgit,
-      coursier,
-      scalatest.withRevision(
-        "3.2.0"
-      ), // make sure testkit clients can use recent 3.x versions
-      scalametaTeskit
-    ),
+    libraryDependencies ++= {
+      if (!isScala3.value) {
+        List(
+          jgit,
+          coursier,
+          scalametaTeskit
+        ) ++ scalatestDeps.value,
+      } else {
+        List(
+          jgit,
+          coursier
+            .exclude("org.scala-lang.modules", "scala-xml_2.13"),
+          scalametaTeskit
+            .exclude("com.lihaoyi", "sourcecode_2.13")
+            .exclude("org.scala-lang.modules", "scala-collection-compat_2.13")
+            .exclude("org.scalameta", "munit_2.13"),
+          ("org.scalameta" %% "munit" % "0.7.29")
+        ) ++ scalatestDeps.value,
+      }
+    },
     Compile / compile / compileInputs := {
       (Compile / compile / compileInputs)
         .dependsOn(
@@ -329,6 +340,11 @@ lazy val unit = projectMatrix
     }
   )
   .defaultAxes(VirtualAxis.jvm)
+  .jvmPlatform(
+    scalaVersions = Seq(scala3),
+    axisValues = Seq(TargetAxis(scala3)),
+    settings = Seq()
+  )
   .jvmPlatform(
     scalaVersions = Seq(scala212),
     axisValues = Seq(TargetAxis(scala3)),

project/Dependencies.scala

@@ -34,13 +34,14 @@ object Dependencies {
   val scalaXmlV = "2.1.0"
   val scalaXml211V = "1.3.0" // scala-xml stops publishing for scala 2.11
   val scalametaV = "4.5.13"
-  val scalatestV = "3.0.8" // don't bump, to avoid forcing breaking changes on clients via eviction
-  val scalatest3V = "3.2.13"
+  val scalatestMinV = "3.0.8" // don't bump, to avoid forcing breaking changes on clients via eviction
+  val scalatestLatestV = "3.2.13"
 
   val bijectionCore = "com.twitter" %% "bijection-core" % bijectionCoreV
   val collectionCompat = "org.scala-lang.modules" %% "scala-collection-compat" % collectionCompatV
   val commonText = "org.apache.commons" % "commons-text" % commontTextV
-  val coursier = "io.get-coursier" %% "coursier" % coursierV
+  val coursier = ("io.get-coursier" %% "coursier" % coursierV)
+    .cross(CrossVersion.for3Use2_13)
   val coursierInterfaces = "io.get-coursier" % "interface" % coursierInterfaceV
   val googleDiff = "com.googlecode.java-diff-utils" % "diffutils" % googleDiffV
   val java8Compat = "org.scala-lang.modules" %% "scala-java8-compat" % java8CompatV
@@ -57,8 +58,9 @@ object Dependencies {
   // https://github.com/scalameta/scalameta/issues/2485
   val scalameta = ("org.scalameta" %% "scalameta" % scalametaV)
     .cross(CrossVersion.for3Use2_13)
-  val scalametaTeskit = "org.scalameta" %% "testkit" % scalametaV
-  val scalatest = "org.scalatest" %% "scalatest" % scalatestV
+  val scalametaTeskit = ("org.scalameta" %% "testkit" % scalametaV)
+    .cross(CrossVersion.for3Use2_13)
+  val scalatest = "org.scalatest" %% "scalatest" % scalatestMinV
   val semanticdbScalacCore = "org.scalameta" % "semanticdb-scalac-core" % scalametaV cross CrossVersion.full
 
   private def previousVersions(scalaVersion: String): List[String] = {

project/ScalafixBuild.scala

@@ -123,6 +123,11 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
     lazy val buildInfoSettingsForRules: Seq[Def.Setting[_]] = Seq(
       buildInfoObject := "RulesBuildInfo"
     )
+
+    lazy val scalatestDeps = Def.setting {
+      if (isScala3.value) Seq(scalatest.withRevision(scalatestLatestV))
+      else Seq(scalatest)
+    }
   }
 
   import autoImport._
@@ -147,7 +152,8 @@ object ScalafixBuild extends AutoPlugin with GhpagesKeys {
         "rules3/compile" ::
         "reflect3/compile" ::
         "cli3/compile" ::
-        "testkit3/compile" :: // TODO replace core rules and reflect with unit3 in the end
+        "testkit3/compile" ::
+        "unit3Target3/compile" :: // TODO replace core rules and reflect with unit3 in the end
         s
     },
     commands += Command.command("ci-213") { s =>

scalafix-tests/unit/src/main/scala/scalafix/test/ExplicitSynthetic.scala

@@ -37,7 +37,7 @@ class ExplicitSynthetic() extends SemanticRule("ExplicitSynthetic") {
           Patch.addRight(t, ".apply")
         }
     }
-    patches.flatten.asPatch + Patch.replaceTree(q"a", "b")
+    patches.flatten.asPatch + Patch.replaceTree(Term.Name("a"), "b")
   }
 
 }

scalafix-tests/unit/src/main/scala/scalafix/test/FqnRule.scala

@@ -3,6 +3,8 @@ package banana.rule
 import scala.meta._
 import scala.meta.contrib._
 
+import scalafix.XtensionOptionPatch
+import scalafix.XtensionSeqPatch
 import scalafix.patch.Patch
 import scalafix.util.SymbolMatcher
 import scalafix.v0
@@ -11,7 +13,12 @@ import scalafix.v1
 case class FqnRule(index: v0.SemanticdbIndex)
     extends v0.SemanticRule(index, "FqnRule") {
   override def fix(ctx: v0.RuleCtx): Patch =
-    ctx.addGlobalImport(importer"scala.collection.immutable") + {
+    ctx.addGlobalImport(
+      Importer(
+        Term.Select(Term.Name("scala"), Term.Name("collection")),
+        List(Importee.Name(Name("immutable")))
+      )
+    ) + {
       val fqnRule = SymbolMatcher.exact(v0.Symbol("test/FqnRule."))
       ctx.tree.collect { case fqnRule(t: Term.Name) =>
         ctx.addLeft(t, "/* matched */ ")

scalafix-tests/unit/src/main/scala/scalafix/test/NoNull.scala

@@ -1,13 +1,17 @@
 package scalafix.test
 
-import scala.meta._
+import scala.meta.Lit
+import scala.meta.XtensionCollectionLikeUI
 
-import scalafix.v0._
+import scalafix.lint.Diagnostic
+import scalafix.v0.LintCategory
+import scalafix.v0.Rule
+import scalafix.v0.RuleCtx
 
 object NoNull extends Rule("NoNull") {
   val error: LintCategory = LintCategory.error("Nulls are not allowed.")
 
   override def check(ctx: RuleCtx): List[Diagnostic] = ctx.tree.collect {
-    case nil @ q"null" => error.at(nil.pos)
+    case nil @ Lit.Null() => error.at(nil.pos)
   }
 }