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 8206986
  27  * @summary Ensure CaseTree methods return expected values
  28  * @modules jdk.compiler
  29  */
  30 
  31 import java.io.IOException;
  32 import java.io.StringWriter;
  33 import java.net.URI;
  34 import java.util.ArrayList;
  35 import java.util.Arrays;
  36 import java.util.List;
  37 import java.util.stream.Collectors;
  38 
  39 import javax.tools.*;
  40 
  41 import com.sun.source.tree.CaseTree;
  42 import com.sun.source.tree.CompilationUnitTree;
  43 import com.sun.source.tree.Tree;
  44 import com.sun.source.util.JavacTask;
  45 import com.sun.source.util.TreePathScanner;
  46 
  47 public class CaseTest {
  48 
  49     public static void main(String[] args) throws Exception {
  50         new CaseTest().testLabels();
  51         new CaseTest().testStatement();
  52         new CaseTest().testRule();
  53     }
  54 
  55     void testLabels() throws Exception {
  56         String code = "class Test {\n" +
  57                       "    void t(int i) {\n" +
  58                       "         switch(i) {\n" +
  59                       "              case 0: break;\n" +
  60                       "              case 1, 2: breal;\n" +
  61                       "              default: breal;\n" +
  62                       "         }\n" +
  63                       "    }\n" +
  64                       "}\n";
  65         List<String> labels = new ArrayList<>();
  66         new TreePathScanner<Void, Void>() {
  67             @Override
  68             public Void visitCase(CaseTree node, Void p) {
  69                 labels.add(String.valueOf(node.getExpression()));
  70                 labels.add(node.getExpressions().stream()
  71                                                 .map(String::valueOf)
  72                                                 .collect(Collectors.joining(",", "[", "]")));
  73                 return super.visitCase(node, p);
  74             }
  75         }.scan(parse(code), null);
  76 
  77         List<String> expected = Arrays.asList("0", "[0]", "1", "[1,2]", "null", "[]");
  78 
  79         if (!expected.equals(labels)) {
  80             throw new AssertionError("Unexpected labels found: " + labels);
  81         }
  82     }
  83 
  84     void testStatement() throws Exception {
  85         String code = "class Test {\n" +
  86                       "    void t(int i) {\n" +
  87                       "         switch(i) {\n" +
  88                       "              case 0:" +
  89                       "                  System.err.println();\n" +
  90                       "                  break;\n" +
  91                       "         }\n" +
  92                       "    }\n" +
  93                       "}\n";
  94         new TreePathScanner<Void, Void>() {
  95             @Override
  96             public Void visitCase(CaseTree node, Void p) {
  97                 if (node.getStatements().size() != 2) {
  98                     throw new AssertionError("Unexpected statements: " + node.getStatements());
  99                 }
 100                 if (node.getBody() != null) {
 101                     throw new AssertionError("Unexpected body: " + node.getBody());
 102                 }
 103                 return super.visitCase(node, p);
 104             }
 105         }.scan(parse(code), null);
 106     }
 107 
 108     void testRule() throws Exception {
 109         String code = "class Test {\n" +
 110                       "    void t(int i) {\n" +
 111                       "         switch(i) {\n" +
 112                       "              case 0 -> {" +
 113                       "                  System.err.println();\n" +
 114                       "              };\n" +
 115                       "         }\n" +
 116                       "    }\n" +
 117                       "}\n";
 118         new TreePathScanner<Void, Void>() {
 119             @Override
 120             public Void visitCase(CaseTree node, Void p) {
 121                 if (node.getStatements() != null) {
 122                     throw new AssertionError("Unexpected statements: " + node.getStatements());
 123                 }
 124                 if (node.getBody().getKind() != Tree.Kind.BLOCK) {
 125                     throw new AssertionError("Unexpected body: " + node.getBody());
 126                 }
 127                 return super.visitCase(node, p);
 128             }
 129         }.scan(parse(code), null);
 130     }
 131 
 132     private CompilationUnitTree parse(String code) throws IOException {
 133         final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();
 134         assert tool != null;
 135         DiagnosticListener<JavaFileObject> noErrors = d -> {};
 136 
 137         StringWriter out = new StringWriter();
 138         JavacTask ct = (JavacTask) tool.getTask(out, null, noErrors,
 139             List.of("-XDdev", "--enable-preview", "-source", "12"), null,
 140             Arrays.asList(new MyFileObject(code)));
 141         return ct.parse().iterator().next();
 142     }
 143 
 144     static class MyFileObject extends SimpleJavaFileObject {
 145         private String text;
 146 
 147         public MyFileObject(String text) {
 148             super(URI.create("myfo:/Test.java"), JavaFileObject.Kind.SOURCE);
 149             this.text = text;
 150         }
 151 
 152         @Override
 153         public CharSequence getCharContent(boolean ignoreEncodingErrors) {
 154             return text;
 155         }
 156     }
 157 }