From fd9e1cd92985c8c798851667408d12285ed718cc Mon Sep 17 00:00:00 2001
From: Adrien Piquerez <adrien.piquerez@gmail.com>
Date: Thu, 18 Mar 2021 15:15:11 +0100
Subject: [PATCH] No binary scala warning if 3 and 2.13

---
 .../sbt/internal/librarymanagement/IvyScalaUtil.scala     | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/ivy/src/main/scala/sbt/internal/librarymanagement/IvyScalaUtil.scala b/ivy/src/main/scala/sbt/internal/librarymanagement/IvyScalaUtil.scala
index 2a4e4a27f..98e8b6721 100644
--- a/ivy/src/main/scala/sbt/internal/librarymanagement/IvyScalaUtil.scala
+++ b/ivy/src/main/scala/sbt/internal/librarymanagement/IvyScalaUtil.scala
@@ -144,7 +144,13 @@ object IvyScalaUtil {
       val depBinaryVersion = CrossVersion.binaryScalaVersion(id.getRevision)
       def isScalaLangOrg = id.getOrganisation == scalaOrganization
       def isScalaArtifact = scalaArtifacts.contains[String](id.getName)
-      def hasBinVerMismatch = depBinaryVersion != scalaBinaryVersion
+
+      def hasBinVerMismatch =
+        depBinaryVersion != scalaBinaryVersion &&
+          // scala 2.13 is compatible with scala 3.x
+          Seq(depBinaryVersion, scalaBinaryVersion)
+            .forall(bv => bv.startsWith("3") || bv.startsWith("2.13"))
+
       def matchesOneOfTheConfigs = dep.getModuleConfigurations exists { scalaVersionConfigs }
       val mismatched = isScalaLangOrg && isScalaArtifact && hasBinVerMismatch && matchesOneOfTheConfigs
       if (mismatched)