1 /*
   2  * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @bug 8214031
  27  * @summary Verify various corner cases with nested switch expressions.
  28  * @compile --enable-preview -source 13 ExpressionSwitchBugsInGen.java
  29  * @run main/othervm --enable-preview ExpressionSwitchBugsInGen
  30  */
  31 
  32 public class ExpressionSwitchBugsInGen {
  33     public static void main(String... args) {
  34         new ExpressionSwitchBugsInGen().test(0, 0, 0, false);
  35         new ExpressionSwitchBugsInGen().test(0, 0, 1, true);
  36         new ExpressionSwitchBugsInGen().test(0, 1, 1, false);
  37         new ExpressionSwitchBugsInGen().test(1, 1, -1, true);
  38         new ExpressionSwitchBugsInGen().test(1, 12, -1, false);
  39         new ExpressionSwitchBugsInGen().testCommonSuperType(0, "a", new StringBuilder(), "a");
  40         new ExpressionSwitchBugsInGen().testCommonSuperType(1, "", new StringBuilder("a"), "a");
  41         new ExpressionSwitchBugsInGen().testSwitchExpressionInConditional(0, null, -1);
  42         new ExpressionSwitchBugsInGen().testSwitchExpressionInConditional(1, "", 0);
  43         new ExpressionSwitchBugsInGen().testSwitchExpressionInConditional(1, 1, 1);
  44         new ExpressionSwitchBugsInGen().testIntBoxing(0, 10, 10);
  45         new ExpressionSwitchBugsInGen().testIntBoxing(1, 10, -1);
  46     }
  47 
  48     private void test(int a, int b, int c, boolean expected) {
  49         if ( !(switch (a) {
  50                 case 0 -> b == (switch (c) { case 0 -> 0; default -> 1; });
  51                 default -> b == 12;
  52             })) {
  53             if (!expected) {
  54                 throw new IllegalStateException();
  55             }
  56         } else {
  57             if (expected) {
  58                 throw new IllegalStateException();
  59             }
  60         }
  61     }
  62 
  63     private void testCommonSuperType(int a, String s1, StringBuilder s2, String expected) {
  64         String r = (switch (a) {
  65             case 0 -> s1;
  66             default -> s2;
  67         }).toString();
  68         if (!expected.equals(r)) {
  69             throw new IllegalStateException();
  70         }
  71     }
  72 
  73     private void testSwitchExpressionInConditional(int a, Object o, int expected) {
  74         int v = a == 0 ? -1
  75                        : switch (o instanceof String ? 0 : 1) {
  76                              case 0 -> 0;
  77                              default -> 1;
  78                        };
  79         if (v != expected) {
  80             throw new IllegalStateException();
  81         }
  82     }
  83 
  84     private void testIntBoxing(int a, Integer res, int expected) {
  85         int r = switch (a) {
  86             case 0 -> res;
  87             default -> -1;
  88         };
  89         if (r != expected) {
  90             throw new IllegalStateException();
  91         }
  92     }
  93 
  94 }