From 1730d8aedf17c4730b8c1810b0d2a825a2f64914 Mon Sep 17 00:00:00 2001
From: Eugene Yokota <eed3si9n@gmail.com>
Date: Tue, 19 Nov 2024 04:34:53 -0500
Subject: [PATCH] fix: Remove "One of these files" error

**Problem**
See gh-21973. Currently the ambiguous symbol detection raises
false positives when used together with `-Wunused:imports`.

**Solution**
Remove the faulty ambiguous symbol detection for now.
---
 .../src/dotty/tools/dotc/core/SymDenotations.scala   |  3 ---
 sbt-test/jar-dependencies/jar/a/A.scala              |  6 ++++++
 sbt-test/jar-dependencies/jar/b/B.scala              |  3 +++
 sbt-test/jar-dependencies/jar/build.sbt              |  8 ++++++++
 .../jar/project/DottyInjectedPlugin.scala            | 12 ++++++++++++
 sbt-test/jar-dependencies/jar/test                   |  3 +++
 6 files changed, 32 insertions(+), 3 deletions(-)
 create mode 100644 sbt-test/jar-dependencies/jar/a/A.scala
 create mode 100644 sbt-test/jar-dependencies/jar/b/B.scala
 create mode 100644 sbt-test/jar-dependencies/jar/build.sbt
 create mode 100644 sbt-test/jar-dependencies/jar/project/DottyInjectedPlugin.scala
 create mode 100644 sbt-test/jar-dependencies/jar/test

diff --git a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
index f54b8a62fa25..1a3d7fb81d17 100644
--- a/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
+++ b/compiler/src/dotty/tools/dotc/core/SymDenotations.scala
@@ -2552,9 +2552,6 @@ object SymDenotations {
                  |  $chosen
                  |and also in
                  |  $f"""
-            if youngest.size > 1 then
-              throw TypeError(em"""${ambiguousFilesMsg(youngest.tail.head)}
-                                  |One of these files should be removed from the classpath.""")
 
             // Warn if one of the older files comes from a different container.
             // In that case picking the youngest file is not necessarily what we want,
diff --git a/sbt-test/jar-dependencies/jar/a/A.scala b/sbt-test/jar-dependencies/jar/a/A.scala
new file mode 100644
index 000000000000..5c6b224b4f3c
--- /dev/null
+++ b/sbt-test/jar-dependencies/jar/a/A.scala
@@ -0,0 +1,6 @@
+package example:
+  trait A:
+    def foo: String = ???
+
+package object example extends A:
+  def foo(x: String): String = ???
diff --git a/sbt-test/jar-dependencies/jar/b/B.scala b/sbt-test/jar-dependencies/jar/b/B.scala
new file mode 100644
index 000000000000..c32bf972949b
--- /dev/null
+++ b/sbt-test/jar-dependencies/jar/b/B.scala
@@ -0,0 +1,3 @@
+import example.*
+
+@main def main = foo
diff --git a/sbt-test/jar-dependencies/jar/build.sbt b/sbt-test/jar-dependencies/jar/build.sbt
new file mode 100644
index 000000000000..75754c9ece3e
--- /dev/null
+++ b/sbt-test/jar-dependencies/jar/build.sbt
@@ -0,0 +1,8 @@
+ThisBuild / organization := "com.example"
+
+lazy val a = project
+
+lazy val b = project
+  .settings(
+    Compile / unmanagedJars += (a / Compile / packageBin).map(Attributed.blank).value
+  )
diff --git a/sbt-test/jar-dependencies/jar/project/DottyInjectedPlugin.scala b/sbt-test/jar-dependencies/jar/project/DottyInjectedPlugin.scala
new file mode 100644
index 000000000000..b85c4f478ad7
--- /dev/null
+++ b/sbt-test/jar-dependencies/jar/project/DottyInjectedPlugin.scala
@@ -0,0 +1,12 @@
+import sbt._
+import Keys._
+
+object DottyInjectedPlugin extends AutoPlugin {
+  override def requires = plugins.JvmPlugin
+  override def trigger = allRequirements
+
+  override val projectSettings = Seq(
+    scalaVersion := sys.props("plugin.scalaVersion"),
+    scalacOptions ++= List("-Werror", "-Wunused:imports"),
+  )
+}
diff --git a/sbt-test/jar-dependencies/jar/test b/sbt-test/jar-dependencies/jar/test
new file mode 100644
index 000000000000..a9d03178fccb
--- /dev/null
+++ b/sbt-test/jar-dependencies/jar/test
@@ -0,0 +1,3 @@
+# https://github.com/scala/scala3/issues/17394
+
+> b/compile