Improve varargs handling (#353)

common/src/main/scala/org/mockito/internal/handler/ScalaMockHandler.scala

@@ -77,7 +77,7 @@ class ScalaMockHandler[T](mockSettings: MockCreationSettings[T], methodsToProces
       .getOrElse(args)
 
     //For some border cases, we can't extract the varargs in the nice way, so we try the brute force one
-    if (args.length != transformed.length) transformed
+    if (methodsToProcess.isEmpty || args.length != transformed.length) transformed
     else unwrapVarargs(transformed)
   }
 }

scalatest/src/test/scala-2.13/user/org/mockito/Issue352_213.scala

@@ -0,0 +1,34 @@
+package user.org.mockito
+
+import org.mockito.scalatest.MockitoSugar
+import org.scalatest.funspec.AnyFunSpec
+import org.scalatest.matchers.should.Matchers
+
+import scala.collection.immutable.ArraySeq
+
+class Issue352_213 extends AnyFunSpec with Matchers with MockitoSugar {
+
+  trait IndexedSeqService {
+    def testMethod(str: String, args: IndexedSeq[String]): IndexedSeq[String]
+  }
+  trait ArraySeqService {
+    def testMethod(str: String, args: ArraySeq[String]): IndexedSeq[String]
+  }
+
+  describe("Mockito") {
+    it("should allow ArraySeq as a last parameter") {
+      val arraySeq = mock[ArraySeqService]
+      when(arraySeq.testMethod(*, *)).thenAnswer[String, ArraySeq[String]] { (fst, rst) =>
+        fst +: rst
+      }
+      arraySeq.testMethod("a", ArraySeq("b", "c")).should(contain).allOf("a", "b", "c")
+    }
+    it("should allow ArraySeq as a last parameter to IndexedSeq method") {
+      val indexedSeq = mock[IndexedSeqService]
+      when(indexedSeq.testMethod(*, *)).thenAnswer[String, IndexedSeq[String]] { (fst, rst) =>
+        fst +: rst
+      }
+      indexedSeq.testMethod("a", ArraySeq("b", "c")).should(contain).allOf("a", "b", "c")
+    }
+  }
+}

scalatest/src/test/scala/user/org/mockito/Issue352.scala

@@ -0,0 +1,46 @@
+package user.org.mockito
+
+import org.mockito.scalatest.MockitoSugar
+import org.scalatest.funspec.AnyFunSpec
+import org.scalatest.matchers.should.Matchers
+
+class Issue352 extends AnyFunSpec with Matchers with MockitoSugar {
+
+  trait IndexedSeqService {
+    def testMethod(str: String, args: IndexedSeq[String]): IndexedSeq[String]
+  }
+  trait VarArgsService {
+    def testMethod(str: String, args: String*): IndexedSeq[String]
+  }
+
+  describe("Mockito") {
+    it("should allow Vector as a last parameter to IndexedSeq method") {
+      val indexedSeq = mock[IndexedSeqService]
+      when(indexedSeq.testMethod(*, *)).thenAnswer[String, IndexedSeq[String]] { (fst, rst) =>
+        fst +: rst
+      }
+      indexedSeq.testMethod("a", Vector("b", "c")).should(contain).allOf("a", "b", "c")
+    }
+    it("should allow varargs as a last parameter to IndexedSeq method 2 varargs") {
+      val varargSeq = mock[VarArgsService]
+      when(varargSeq.testMethod(*, *)).thenAnswer[String, String, String] { (v0, v1, v2) =>
+        IndexedSeq(v0, v1, v2)
+      }
+      varargSeq.testMethod("a", "b", "c").should(contain).allOf("a", "b", "c")
+    }
+    it("should allow varargs as a last parameter to IndexedSeq method 1 vararg") {
+      val varargSeq = mock[VarArgsService]
+      when(varargSeq.testMethod(*, *)).thenAnswer[String, String] { (v0, v1) =>
+        IndexedSeq(v0, v1)
+      }
+      varargSeq.testMethod("a", "b").should(contain).allOf("a", "b")
+    }
+    it("should allow varargs as a last parameter to IndexedSeq method no vararg") {
+      val varargSeq = mock[VarArgsService]
+      when(varargSeq.testMethod(*, *)).thenAnswer[String] { v0 =>
+        IndexedSeq(v0)
+      }
+      varargSeq.testMethod("a").should(contain).only("a")
+    }
+  }
+}