Merge pull request #3615 from retronym/ticket/8376

SI-8376 Fix overload resolution with Java varargs

7 files changed, 41 insertions, 2 deletions

diff --git a/src/reflect/scala/reflect/internal/Definitions.scala b/src/reflect/scala/reflect/internal/Definitions.scala
index fa1694c527..25d78f4e6f 100644
--- a/src/reflect/scala/reflect/internal/Definitions.scala
+++ b/src/reflect/scala/reflect/internal/Definitions.scala
@@ -410,7 +410,8 @@ trait Definitions extends api.StandardDefinitions {
       else if (isScalaRepeatedParamType(tp)) elementExtract(RepeatedParamClass, tp) orElse tp
       else tp
     )
-    def repeatedToSingle(tp: Type): Type                     = elementExtract(RepeatedParamClass, tp) orElse tp
+    def repeatedToSingle(tp: Type): Type                     = elementExtract(RepeatedParamClass, tp) orElse elementExtract(JavaRepeatedParamClass, tp) orElse tp
+     // We don't need to deal with JavaRepeatedParamClass here, as `repeatedToSeq` is only called in the patmat translation for Scala sources.
     def repeatedToSeq(tp: Type): Type                        = elementTransform(RepeatedParamClass, tp)(seqType) orElse tp
     def seqToRepeated(tp: Type): Type                        = elementTransform(SeqClass, tp)(scalaRepeatedType) orElse tp
     def isReferenceArray(tp: Type)                           = elementTest(ArrayClass, tp)(_ <:< AnyRefTpe)
diff --git a/src/reflect/scala/reflect/internal/Types.scala b/src/reflect/scala/reflect/internal/Types.scala
index e9e5a89aa7..eb56f4ba81 100644
--- a/src/reflect/scala/reflect/internal/Types.scala
+++ b/src/reflect/scala/reflect/internal/Types.scala
@@ -2271,7 +2271,7 @@ trait Types
       case _          => args.mkString("(", ", ", ")")
     }
     private def customToString = sym match {
-      case RepeatedParamClass => args.head + "*"
+      case RepeatedParamClass | JavaRepeatedParamClass => args.head + "*"
       case ByNameParamClass   => "=> " + args.head
       case _                  =>
         if (isFunctionTypeDirect(this)) {
diff --git a/test/files/neg/t8376.check b/test/files/neg/t8376.check
new file mode 100644
index 0000000000..22ed942d51
--- /dev/null
+++ b/test/files/neg/t8376.check
@@ -0,0 +1,7 @@
+S.scala:2: error: overloaded method value m with alternatives:
+  (a: J*)Unit <and>
+  (a: String*)Unit
+ cannot be applied to (Int)
+  J.m(0)
+    ^
+one error found
diff --git a/test/files/neg/t8376/J.java b/test/files/neg/t8376/J.java
new file mode 100644
index 0000000000..29aa23da84
--- /dev/null
+++ b/test/files/neg/t8376/J.java
@@ -0,0 +1,4 @@
+class J {
+  public static void m(String... a) { }
+  public static void m(J... a) { }
+}
diff --git a/test/files/neg/t8376/S.scala b/test/files/neg/t8376/S.scala
new file mode 100644
index 0000000000..a19f0d3c06
--- /dev/null
+++ b/test/files/neg/t8376/S.scala
@@ -0,0 +1,4 @@
+object S {
+  J.m(0)
+  // the error message should show `T*` in the method signatures rather than `<repeated>[T]`
+}
diff --git a/test/files/pos/t8376/BindingsX.java b/test/files/pos/t8376/BindingsX.java
new file mode 100644
index 0000000000..165fdaf5f6
--- /dev/null
+++ b/test/files/pos/t8376/BindingsX.java
@@ -0,0 +1,13 @@
+/**
+ * A simple Java class implementing methods similar to new JavaFX `Bindings`.
+ */
+public final class BindingsX {
+
+    public static void select(String root, String... steps) {
+        throw new UnsupportedOperationException("Not implemented");
+    }
+
+    public static void select(Object root, String... steps) {
+        throw new UnsupportedOperationException("Not implemented");
+    }
+}
diff --git a/test/files/pos/t8376/Test.scala b/test/files/pos/t8376/Test.scala
new file mode 100644
index 0000000000..ba078a3532
--- /dev/null
+++ b/test/files/pos/t8376/Test.scala
@@ -0,0 +1,10 @@
+class Test {
+  BindingsX.select("", "") // okay in 2.10, fails in 2.11
+
+  BindingsY.select1("", "") // okay in both
+}
+
+object BindingsY {
+  def select1(root: String, steps: String*) = ()  
+  def select1(root: Any, steps: String*) = ()
+}