[guava] fix: resolve implicit conflict for top level collection funne…

…ls (#936)

* [guava] fix: resolve implicit conflict for top level collection funnels

* Fix / filter binary issues

build.sbt

@@ -220,7 +220,10 @@ ThisBuild / githubWorkflowAddedJobs ++= Seq(
 )
 
 // mima
-ThisBuild / mimaBinaryIssueFilters ++= Seq()
+ThisBuild / mimaBinaryIssueFilters ++= Seq(
+  // genFunnelMacro should not be available to users
+  ProblemFilters.exclude[DirectMissingMethodProblem]("magnolify.guava.auto.package.genFunnelMacro")
+)
 ThisBuild / tlVersionIntroduced := Map("3" -> "0.8.0")
 
 // protobuf

guava/src/main/scala/magnolify/guava/GuavaMacros.scala

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2024 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package magnolify.guava
+
+import scala.reflect.macros.whitebox
+
+private object GuavaMacros {
+  def genFunnelMacro[T: c.WeakTypeTag](c: whitebox.Context): c.Tree = {
+    import c.universe._
+    val wtt = weakTypeTag[T]
+    q"""_root_.magnolify.guava.semiauto.FunnelDerivation.apply[$wtt]"""
+  }
+}

guava/src/main/scala/magnolify/guava/auto/package.scala

@@ -19,14 +19,8 @@ package magnolify.guava
 import com.google.common.hash.Funnel
 import magnolify.guava.semiauto.FunnelImplicits
 
-import scala.reflect.macros._
+package object auto extends FunnelImplicits with LowPriorityImplicits
 
-package object auto extends FunnelImplicits {
-  def genFunnelMacro[T: c.WeakTypeTag](c: whitebox.Context): c.Tree = {
-    import c.universe._
-    val wtt = weakTypeTag[T]
-    q"""_root_.magnolify.guava.semiauto.FunnelDerivation.apply[$wtt]"""
-  }
-
-  implicit def genFunnel[T]: Funnel[T] = macro genFunnelMacro[T]
+trait LowPriorityImplicits {
+  implicit def genFunnel[T]: Funnel[T] = macro GuavaMacros.genFunnelMacro[T]
 }

guava/src/test/scala/magnolify/guava/FunnelDerivationSuite.scala

@@ -71,6 +71,11 @@ class FunnelDerivationSuite extends MagnolifySuite {
   test[Collections]
   test[Custom]
 
+  // test unwrapped
+  test[Int]
+  test[List[Int]]
+  test[List[Required]]
+
   test("AnyVal") {
     implicit val f: Funnel[HasValueClass] = FunnelDerivation[HasValueClass]
     test[HasValueClass]