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 * 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

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 *

 * 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.

 *

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 * questions.

 */

/*

 * @test

 * @bug 8206986

 * @summary Ensure rule cases can be parsed correctly for complex expressions.

 * @modules jdk.compiler

 */

import java.io.StringWriter;

import java.net.URI;

import java.util.AbstractMap.SimpleEntry;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.Locale;

import java.util.Map.Entry;

import javax.tools.*;

import com.sun.source.tree.CaseTree;

import com.sun.source.tree.CompilationUnitTree;

import com.sun.source.util.JavacTask;

import com.sun.source.util.TreePathScanner;

import com.sun.source.util.Trees;

public class RuleParsingTest {

    public static void main(String[] args) throws Exception {

        new RuleParsingTest().testParseComplexExpressions();

    }

    void testParseComplexExpressions() throws Exception {

        String[] expressions = {

            "(a)",

            "a",

            "a + a",

            "~a + a",

            "a = a",

            "a += a",

            "a + (a)",

            "a + (a) b",

            "true ? a : b",

            "m(() -> {})",

            "m(() -> 1)",

            "m(a -> 1)",

            "m((t a) -> 1)",

        };

        StringBuilder code = new StringBuilder();

        List<Entry<Long, Long>> spans = new ArrayList<>();

        code.append("class Test {\n" +

                    "    void t(int i) {\n");

        for (boolean switchExpr : new boolean[] {false, true}) {

            if (switchExpr) {

                code.append("         int j = switch(i) {\n");

            } else {

                code.append("         switch(i) {\n");

            }

            for (String expr : expressions) {

                code.append("case ");

                int start = code.length();

                code.append(expr);

                spans.add(new SimpleEntry<>((long) start, (long) code.length()));

                code.append(" -> {}");

            }

            code.append("         };\n");

        }

        code.append("    }\n" +

                    "}\n");

        final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();

        assert tool != null;

        DiagnosticListener<JavaFileObject> noErrors = d -> { throw new AssertionError(d.getMessage(null)); };

        StringWriter out = new StringWriter();

        JavacTask ct = (JavacTask) tool.getTask(out, null, noErrors,

            Arrays.asList(new MyFileObject(code.toString())));

        CompilationUnitTree cut = ct.parse().iterator().next();

        Trees trees = Trees.instance(ct);

        new TreePathScanner<Void, Void>() {

            @Override

            public Void visitCase(CaseTree node, Void p) {

                long start = trees.getSourcePositions().getStartPosition(cut, node.getExpression());

                long end = trees.getSourcePositions().getEndPosition(cut, node.getExpression());

                if (!spans.remove(new SimpleEntry<>(start, end))) {

                    throw new AssertionError("Did not find an expression span in expected spans: " +

                                             start + "-" + end +

                                             " '" + node.getExpression().toString() + "'");

                }

                return super.visitCase(node, p);

            }

        }.scan(cut, null);

        if (!spans.isEmpty()) {

            throw new AssertionError("Remaning spans: " + spans);

        }

    }

    static class MyFileObject extends SimpleJavaFileObject {

        private String text;

        public MyFileObject(String text) {

            super(URI.create("myfo:/Test.java"), JavaFileObject.Kind.SOURCE);

            this.text = text;

        }

        @Override

        public CharSequence getCharContent(boolean ignoreEncodingErrors) {

            return text;

        }

    }

}