From 99b30b8899d663c1153e88233d691c9a2e0879c8 Mon Sep 17 00:00:00 2001
From: Anatolii Kmetiuk <anatoliikmt@proton.me>
Date: Fri, 22 May 2026 11:24:12 +0900
Subject: [PATCH] Fix duplicate autoplugins packageBin mappings

---
 main/src/main/scala/sbt/Defaults.scala               | 12 ++++++++++--
 .../duplicate-autoplugins-packagebin/build.sbt       |  8 ++++++++
 .../src/main/scala/example/ComponentsPlugin.scala    |  5 +++++
 .../src/main/scala/example/PluginsPlugin.scala       |  5 +++++
 .../src/main/scala/example/ScalacOptionsPlugin.scala |  5 +++++
 .../plugins/duplicate-autoplugins-packagebin/test    |  3 +++
 6 files changed, 36 insertions(+), 2 deletions(-)
 create mode 100644 sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/build.sbt
 create mode 100644 sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/components/src/main/scala/example/ComponentsPlugin.scala
 create mode 100644 sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/plugins/src/main/scala/example/PluginsPlugin.scala
 create mode 100644 sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/scalac-options/src/main/scala/example/ScalacOptionsPlugin.scala
 create mode 100644 sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/test

diff --git a/main/src/main/scala/sbt/Defaults.scala b/main/src/main/scala/sbt/Defaults.scala
index 7a9485e98..b45a34f23 100644
--- a/main/src/main/scala/sbt/Defaults.scala
+++ b/main/src/main/scala/sbt/Defaults.scala
@@ -1772,10 +1772,18 @@ object Defaults extends BuildCommon with DefExtra {
   def packageBinMappings: Initialize[Task[Seq[(HashedVirtualFileRef, String)]]] =
     Def.task {
       val converter = fileConverter.value
+      val classDirPath = classDirectory.value.toPath.toAbsolutePath.normalize
       val xs = products.value
-      xs
+      val allMappings = xs
         .flatMap(Path.allSubpaths)
-        .withFilter(_._1.isFile())
+        .filter(_._1.isFile())
+      val resourcePaths = allMappings.collect {
+        case (p, path) if !p.toPath.toAbsolutePath.normalize.startsWith(classDirPath) => path
+      }.toSet
+      allMappings
+        .filterNot { (p, path) =>
+          resourcePaths(path) && p.toPath.toAbsolutePath.normalize.startsWith(classDirPath)
+        }
         .map { (p, path) =>
           val vf = converter.toVirtualFile(p.toPath())
           (vf: HashedVirtualFileRef) -> path
diff --git a/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/build.sbt b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/build.sbt
new file mode 100644
index 000000000..25b1fd20e
--- /dev/null
+++ b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/build.sbt
@@ -0,0 +1,8 @@
+ThisBuild / organization := "com.example"
+ThisBuild / version      := "0.1.0-SNAPSHOT"
+
+val `scalac-options` = project.enablePlugins(SbtPlugin).settings(
+  addSbtPlugin("org.typelevel" % "sbt-tpolecat" % "0.5.4"),
+)
+val components = project.enablePlugins(SbtPlugin)
+val plugins    = project.dependsOn(components, `scalac-options`).enablePlugins(SbtPlugin)
diff --git a/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/components/src/main/scala/example/ComponentsPlugin.scala b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/components/src/main/scala/example/ComponentsPlugin.scala
new file mode 100644
index 000000000..089c9592a
--- /dev/null
+++ b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/components/src/main/scala/example/ComponentsPlugin.scala
@@ -0,0 +1,5 @@
+package example
+
+import sbt.*
+
+object ComponentsPlugin extends AutoPlugin
diff --git a/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/plugins/src/main/scala/example/PluginsPlugin.scala b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/plugins/src/main/scala/example/PluginsPlugin.scala
new file mode 100644
index 000000000..639beb45a
--- /dev/null
+++ b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/plugins/src/main/scala/example/PluginsPlugin.scala
@@ -0,0 +1,5 @@
+package example
+
+import sbt.*
+
+object PluginsPlugin extends AutoPlugin
diff --git a/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/scalac-options/src/main/scala/example/ScalacOptionsPlugin.scala b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/scalac-options/src/main/scala/example/ScalacOptionsPlugin.scala
new file mode 100644
index 000000000..3d8f9eae2
--- /dev/null
+++ b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/scalac-options/src/main/scala/example/ScalacOptionsPlugin.scala
@@ -0,0 +1,5 @@
+package example
+
+import sbt.*
+
+object ScalacOptionsPlugin extends AutoPlugin
diff --git a/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/test b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/test
new file mode 100644
index 000000000..e00f9cbb0
--- /dev/null
+++ b/sbt-app/src/sbt-test/plugins/duplicate-autoplugins-packagebin/test
@@ -0,0 +1,3 @@
+> scalac-options / Compile / packageBin
+> scalac-options / Compile / copyResources
+> scalac-options / Compile / packageBin