/*

 * Copyright (c) 2018, 2019, 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.

 */

/*

 * @test

 * @bug 8206986

 * @summary Ensure than parser can parse incomplete sources

 * @modules jdk.compiler

 */

import java.io.StringWriter;

import java.net.URI;

import java.util.Arrays;

import java.util.List;

import javax.tools.*;

import com.sun.source.util.JavacTask;

public class ParseIncomplete {

    private static final String CODE =

            "public class C {" +

            "    void t1(Integer i) {" +

            "        switch (i) {" +

            "            case null: i++; break;" +

            "            case 0, 1: i++; break;" +

            "            default: i++; break;" +

            "        }" +

            "    }" +

            "    int t2(Integer i) {" +

            "        return switch (i) {" +

            "            case null: yield 0;" +

            "            case 0, 1: yield 1;" +

            "            default: yield 2;" +

            "        }" +

            "    }" +

            "}";

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

        final JavaCompiler tool = ToolProvider.getSystemJavaCompiler();

        assert tool != null;

        DiagnosticListener<JavaFileObject> noErrors = d -> {};

        String sourceVersion = Integer.toString(Runtime.version().feature());

        for (int i = 0; i < CODE.length(); i++) {

            String code = CODE.substring(0, i + 1);

            StringWriter out = new StringWriter();

            try {

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

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

                ct.parse().iterator().next();

            } catch (Throwable t) {

                System.err.println("Unexpected exception for code: " + code);

                System.err.println("output: " + out);

                throw t;

            }

            if (!out.toString().isEmpty()) {

                System.err.println("Unexpected compiler for code: " + code);

                System.err.println(out);

                throw new AssertionError();

            }

        }

    }

    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;

        }

    }

}