1 /*
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   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
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  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.
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  23 
  24 /*
  25  * @test
  26  * @bug 8206986
  27  * @summary Ensure rule cases can be parsed correctly for complex expressions.
  28  * @modules jdk.compiler
  29  */
  30 
  31 import java.io.StringWriter;
  32 import java.net.URI;
  33 import java.util.AbstractMap.SimpleEntry;
  34 import java.util.ArrayList;
  35 import java.util.Arrays;
  36 import java.util.List;
  37 import java.util.Locale;
  38 import java.util.Map.Entry;
  39 
  40 import javax.tools.*;
  41 
  42 import com.sun.source.tree.CaseTree;
  43 import com.sun.source.tree.CompilationUnitTree;
  44 import com.sun.source.util.JavacTask;
  45 import com.sun.source.util.TreePathScanner;
  46 import com.sun.source.util.Trees;
  47 
  48 public class RuleParsingTest {
  49 
  50     public static void main(String[] args) throws Exception {
  51         String sourceVersion = Integer.toString(Runtime.version().feature());
  52         new RuleParsingTest().testParseComplexExpressions(sourceVersion);
  53     }
  54 
  55     void testParseComplexExpressions(String sourceVersion) throws Exception {
  56         String[] expressions = {
  57             "(a)",
  58             "a",
  59             "a + a",
  60             "~a + a",
  61             "a = a",
  62             "a += a",
  63             "a + (a)",
  64             "a + (a) b",
  65             "true ? a : b",
  66             "m(() -> {})",
  67             "m(() -> 1)",
  68             "m(a -> 1)",
  69             "m((t a) -> 1)",
  70         };
  71         StringBuilder code = new StringBuilder();
  72         List<Entry<Long, Long>> spans = new ArrayList<>();
  73         code.append("class Test {\n" +
  74                     "    void t(int i) {\n");
  75         for (boolean switchExpr : new boolean[] {false, true}) {
  76             if (switchExpr) {
  77                 code.append("         int j = switch(i) {\n");
  78             } else {
  79                 code.append("         switch(i) {\n");
  80             }
  81             for (String expr : expressions) {
  82                 code.append("case ");
  83                 int start = code.length();
  84                 code.append(expr);
  85                 spans.add(new SimpleEntry<>((long) start, (long) code.length()));
  86                 code.append(" -> {}");
  87             }
  88             code.append("         };\n");
  89         }
  90         code.append("    }\n" +
  91                     "}\n");
  92         final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();
  93         assert tool != null;
  94         DiagnosticListener<JavaFileObject> noErrors = d -> { throw new AssertionError(d.getMessage(null)); };
  95 
  96         StringWriter out = new StringWriter();
  97         JavacTask ct = (JavacTask) tool.getTask(out, null, noErrors,
  98             List.of(), null,
  99             Arrays.asList(new MyFileObject(code.toString())));
 100         CompilationUnitTree cut = ct.parse().iterator().next();
 101         Trees trees = Trees.instance(ct);
 102         new TreePathScanner<Void, Void>() {
 103             @Override
 104             public Void visitCase(CaseTree node, Void p) {
 105                 long start = trees.getSourcePositions().getStartPosition(cut, node.getExpression());
 106                 long end = trees.getSourcePositions().getEndPosition(cut, node.getExpression());
 107                 if (!spans.remove(new SimpleEntry<>(start, end))) {
 108                     throw new AssertionError("Did not find an expression span in expected spans: " +
 109                                              start + "-" + end +
 110                                              " '" + node.getExpression().toString() + "'");
 111                 }
 112                 return super.visitCase(node, p);
 113             }
 114         }.scan(cut, null);
 115 
 116         if (!spans.isEmpty()) {
 117             throw new AssertionError("Remaning spans: " + spans);
 118         }
 119     }
 120 
 121     static class MyFileObject extends SimpleJavaFileObject {
 122         private String text;
 123 
 124         public MyFileObject(String text) {
 125             super(URI.create("myfo:/Test.java"), JavaFileObject.Kind.SOURCE);
 126             this.text = text;
 127         }
 128 
 129         @Override
 130         public CharSequence getCharContent(boolean ignoreEncodingErrors) {
 131             return text;
 132         }
 133     }
 134 }