Issue3038Test.java

/*
 * Copyright (C) 2013-2024 The JavaParser Team.
 *
 * This file is part of JavaParser.
 *
 * JavaParser can be used either under the terms of
 * a) the GNU Lesser General Public License as published by
 *     the Free Software Foundation, either version 3 of the License, or
 *     (at your option) any later version.
 * b) the terms of the Apache License
 *
 * You should have received a copy of both licenses in LICENCE.LGPL and
 * LICENCE.APACHE. Please refer to those files for details.
 *
 * JavaParser 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 Lesser General Public License for more details.
 */

package com.github.javaparser.symbolsolver;

import com.github.javaparser.ParserConfiguration;
import com.github.javaparser.StaticJavaParser;
import com.github.javaparser.ast.CompilationUnit;
import com.github.javaparser.ast.expr.NameExpr;
import com.github.javaparser.ast.nodeTypes.NodeWithStatements;
import com.github.javaparser.resolution.UnsolvedSymbolException;
import com.github.javaparser.symbolsolver.resolution.AbstractResolutionTest;
import com.github.javaparser.symbolsolver.resolution.typesolvers.ReflectionTypeSolver;
import java.util.List;
import java.util.concurrent.TimeUnit;
import org.junit.jupiter.api.RepeatedTest;
import org.junit.jupiter.api.Timeout;

/**
 * An issue when resolving some name when there are a series of many prior {@link NodeWithStatements}s.
 * Each queues up solving in the prior adjacent statement,
 * which means we queue up a factorial number of duplicate resolve calls.
 * <br>
 * This test verifies that parsing the given code below runs in an non-crazy amount of time <i>(Leeway for slow CI)</i>.
 * Without any fixes applied, this takes multiple hours to run.
 */
public class Issue3038Test extends AbstractResolutionTest {
    // The number of declarations to define
    private static final long MAX_ADJACENT_NODES = 500;
    // In no way should this take more than 2.5 seconds
    // Realistically this should take much less.
    private static final long TIME_LIMIT_MS = 2500;

    @RepeatedTest(10)
    @Timeout(value = TIME_LIMIT_MS, unit = TimeUnit.MILLISECONDS)
    public void test3038() {
        run(generate("        new Thread(){\n" + "            @Override\n"
                + "            public void run() {\n"
                + "                Foo foo = Foo.getInstance();\n"
                + "            }\n"
                + "        }.run();\n"));
    }

    @RepeatedTest(10)
    @Timeout(value = TIME_LIMIT_MS, unit = TimeUnit.MILLISECONDS)
    public void testAlt3038() {
        run(generate("        Foo foo = Foo.getInstance();\n"));
    }

    private void run(String code) {
        ParserConfiguration config = new ParserConfiguration();
        config.setSymbolResolver(new JavaSymbolSolver(new ReflectionTypeSolver(false)));
        StaticJavaParser.setConfiguration(config);

        CompilationUnit cu = StaticJavaParser.parse(code);

        List<NameExpr> exprs = cu.findAll(NameExpr.class);
        for (NameExpr expr : exprs) {
            long start = System.currentTimeMillis();
            try {
                expr.resolve();
            } catch (UnsolvedSymbolException ex) {
                // this is expected since we have no way for the resolver to find "Foo"
            }
            long end = System.currentTimeMillis();
            System.out.printf("Call to resolve '%s' took %dms", expr.toString(), (end - start));
        }
    }

    private String generate(String extra) {
        StringBuilder code =
                new StringBuilder("public class Foo{\n" + "    public static void main(String[] args) {\n");
        for (int i = 0; i < MAX_ADJACENT_NODES; i++) {
            code.append("        String s").append(i).append("   = \"hello\";\n");
        }
        code.append(extra + "    }\n"
                + "    static Foo getInstance() {\n"
                + "        return new Foo();\n"
                + "    }\n"
                + "}");
        return code.toString();
    }
}