eu.numberfour.n4js.JSLibSingleTestConfigProvider.java Source code

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Here is the source code for eu.numberfour.n4js.JSLibSingleTestConfigProvider.java

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/**
 * Copyright (c) 2016 NumberFour AG.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   NumberFour AG - Initial API and implementation
 */
package eu.numberfour.n4js;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.zip.ZipEntry;

import com.google.common.base.Charsets;
import com.google.common.base.Predicate;
import com.google.common.collect.Iterables;
import com.google.common.io.CharStreams;
import com.google.common.io.InputSupplier;

/**
 * Base class for factories creating {@link JSLibSingleTestConfig} with some additional functionality to be aware of
 * blacklists (that is, tests which are supposed to fail). This default implementation supports a blacklist, if the
 * entry is found in the black list, it is marked accordingly. Subclasses may adjust that behavior.
 */
public class JSLibSingleTestConfigProvider {

    /**
     * Line comment char for black lists.
     */
    public static final String BLACKLIST_LINECOMMENT = "#";

    /**
     * The black list, merger of all blacklist provided in constructor.
     */
    protected Set<String> blacklist;

    /**
     * Creates a provider with given black list filenames. These black lists are all merged together.
     */
    public JSLibSingleTestConfigProvider(String... blacklistFileNames) throws IOException {
        blacklist = readModifierFiles(blacklistFileNames);
    }

    /**
     * Creates a configuration from an entry in the given resource.
     */
    public JSLibSingleTestConfig createConfig(ZipEntry entry, String resourceName) {
        final String entryName = entry.getName();
        final String modifier = (blacklist.contains(entryName)) ? JSLibSingleTestConfig.BLACKLIST : null;
        return new JSLibSingleTestConfig(entry, resourceName, modifier);
    }

    /**
     * Merges several blacklists into one, may be used in custom {@link JSLibSingleTestConfigProvider} implementation.
     */
    protected static Set<String> readModifierFiles(String... blacklistFileNames) throws IOException {
        Set<String> blacklist = new HashSet<>();
        if (blacklistFileNames != null) {
            for (String blacklistFileName : blacklistFileNames) {
                Iterable<String> entries = Iterables.filter(getFileLines(blacklistFileName),
                        new Predicate<String>() {
                            @Override
                            public boolean apply(String s) {
                                return !s.startsWith(BLACKLIST_LINECOMMENT) && !s.trim().isEmpty();
                            }
                        });
                for (String entry : entries) {
                    if (!blacklist.add(entry)) {
                        System.err.println("Duplicate blacklist entry: " + entry);
                    }
                }
            }
        }
        return blacklist;
    }

    /**
     * @param resourceName
     *            the classpath-relative location of the to-be-read resource
     */
    private static List<String> getFileLines(final String resourceName) throws IOException {
        InputSupplier<InputStreamReader> readerSupplier = CharStreams
                .newReaderSupplier(new InputSupplier<InputStream>() {
                    @Override
                    public InputStream getInput() throws IOException {
                        return Thread.currentThread().getContextClassLoader().getResourceAsStream(resourceName);
                    }
                }, Charsets.UTF_8);
        return CharStreams.readLines(readerSupplier);
    }

}