8058615: Overload resolution ambiguity involving ConsString

Reviewed-by: lagergren, hannesw

nashorn/src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/runtime/linker/NashornBeansLinker.java

@@ -125,6 +125,15 @@ public class NashornBeansLinker implements GuardingDynamicLinker {
 
         @Override
         public Comparison compareConversion(final Class<?> sourceType, final Class<?> targetType1, final Class<?> targetType2) {
+            if (sourceType == ConsString.class) {
+                if (String.class == targetType1 || CharSequence.class == targetType1) {
+                    return Comparison.TYPE_1_BETTER;
+                }
+
+                if (String.class == targetType2 || CharSequence.class == targetType2) {
+                    return Comparison.TYPE_2_BETTER;
+                }
+            }
             return linkerServices.compareConversion(sourceType, targetType1, targetType2);
         }
     }

nashorn/test/script/basic/JDK-8058615.js

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ * 
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ * 
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ * 
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * JDK-8058615: Overload resolution ambiguity involving ConsString
+ *
+ * @test
+ * @run
+ */
+
+var strw = new java.io.StringWriter();
+var bufw = new java.io.BufferedWriter(strw);
+var s = "hello ";
+bufw.write(s + "world");
+bufw.close();
+print(strw.toString());

nashorn/test/script/basic/JDK-8058615.js.EXPECTED

@@ -0,0 +1 @@
+hello world