import java.io.PrintStream;

import java.util.*;

import java.util.function.Function;

import javax.tools.*;

import static java.lang.System.lineSeparator;

import static java.util.Arrays.asList;

import static java.util.stream.Collectors.joining;

    public static final String LINE_SEPARATOR = lineSeparator();

    private <S> InMemoryFileManager compile(

            List<String> options,

            Function<S, ? extends JavaFileObject> src2JavaFileObject,

            List<S> sources)

            throws IOException, CompilationException {

        JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();

        List<? extends JavaFileObject> src = sources.stream()

                .map(src2JavaFileObject)

                .collect(toList());

        DiagnosticCollector<? super JavaFileObject> dc = new DiagnosticCollector<>();

        try (InMemoryFileManager fileManager

                     = new InMemoryFileManager(compiler.getStandardFileManager(null, null, null))) {

            JavaCompiler.CompilationTask task = compiler.getTask(null, fileManager, dc, options, null, src);

            boolean success = task.call();

            if (!success) {

                String errorMessage = dc.getDiagnostics().stream()

                        .map(Object::toString)

                        .collect(joining("\n"));

                throw new CompilationException("Compilation Error\n\n" + errorMessage);

            }

            return fileManager;

        }

    }

    public InMemoryFileManager compile(String... sources)

            throws IOException, CompilationException {

        return compile(emptyList(), sources);

    }

    /**

     * @param options - compiler options

     * @param sources

     * @return map where key is className, value is corresponding ClassFile.

     * @throws IOException

     */

    public InMemoryFileManager compile(List<String> options, String...sources)

            throws IOException, CompilationException {

        return compile(options, ToolBox.JavaSource::new, asList(sources));

    }

    public InMemoryFileManager compile(String[]... sources) throws IOException,

     * @param sources - sources[i][0] - name of file, sources[i][1] - sources

     * @throws CompilationException

    public InMemoryFileManager compile(List<String> options, String[]...sources)

            throws IOException, CompilationException {

        return compile(options, src -> new ToolBox.JavaSource(src[0], src[1]), asList(sources));

            throw new AssertionFailedException(format("%s%nGot: %s, Expected: %s", message, actual, expected));

    public void assertFalse(boolean actual, String message) {

        assertEquals(actual, false, message);

    }

    public File getSourceDir() {

        return new File(System.getProperty("test.src", "."));

    }

    public File getClassDir() {

        return new File(System.getProperty("test.classes", TestBase.class.getResource(".").getPath()));

    }

        return new File(getSourceDir(), fileName);

        return new File(getClassDir(), fileName);

    public void echo(String message) {

        System.err.println(message.replace("\n", LINE_SEPARATOR));

    }

    public void printf(String template, Object...args) {

        System.err.printf(template, Stream.of(args)

                .map(Objects::toString)

                .map(m -> m.replace("\n", LINE_SEPARATOR))

                .collect(toList())

                .toArray());

    }