Quick fix for applying spread operator where vararg is expected #KT-6824 Fixed

idea/testData/quickfix/changeToUseSpreadOperator/nonArray.kt

@@ -0,0 +1,12 @@
+// "Change 'y' to '*y'" "false"
+// ACTION: Add 'toString()' call
+// ACTION: Change parameter 'x' type of function 'foo' to 'List<String>'
+// ACTION: Convert to block body
+// ACTION: Create function 'foo'
+// DISABLE-ERRORS
+
+// Fix this test case if https://youtrack.jetbrains.com/issue/KT-12663 is implemented
+
+fun foo(vararg x: String) {}
+
+fun bar(y: List<String>) = foo(y<caret>)