MergeConfig.java

/*******************************************************************************
 * Copyright (c) 2014 Konrad Kügler and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0 which is available at
 * https://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 *******************************************************************************/
package org.eclipse.jgit.merge;

import java.io.IOException;

import org.eclipse.jgit.api.MergeCommand.FastForwardMode;
import org.eclipse.jgit.lib.Config;
import org.eclipse.jgit.lib.Config.SectionParser;
import org.eclipse.jgit.lib.ConfigConstants;
import org.eclipse.jgit.lib.Repository;

/**
 * Holds configuration for merging into a given branch
 *
 * @since 3.3
 */
public class MergeConfig {

    /**
     * Get merge configuration for the current branch of the repository
     *
     * @param repo
     *            a {@link org.eclipse.jgit.lib.Repository} object.
     * @return merge configuration for the current branch of the repository
     */
    public static MergeConfig getConfigForCurrentBranch(Repository repo) {
        try {
            String branch = repo.getBranch();
            if (branch != null)
                return repo.getConfig().get(getParser(branch));
        } catch (IOException e) {
            // ignore
        }
        // use defaults if branch can't be determined
        return new MergeConfig();
    }

    /**
     * Get a parser for use with
     * {@link org.eclipse.jgit.lib.Config#get(SectionParser)}
     *
     * @param branch
     *            short branch name to get the configuration for, as returned
     *            e.g. by {@link org.eclipse.jgit.lib.Repository#getBranch()}
     * @return a parser for use with
     *         {@link org.eclipse.jgit.lib.Config#get(SectionParser)}
     */
    public static final SectionParser<MergeConfig> getParser(
            final String branch) {
        return new MergeConfigSectionParser(branch);
    }

    private final FastForwardMode fastForwardMode;

    private final boolean squash;

    private final boolean commit;

    private MergeConfig(String branch, Config config) {
        String[] mergeOptions = getMergeOptions(branch, config);
        fastForwardMode = getFastForwardMode(config, mergeOptions);
        squash = isMergeConfigOptionSet("--squash", mergeOptions); //$NON-NLS-1$
        commit = !isMergeConfigOptionSet("--no-commit", mergeOptions); //$NON-NLS-1$
    }

    private MergeConfig() {
        fastForwardMode = FastForwardMode.FF;
        squash = false;
        commit = true;
    }

    /**
     * Get the fast forward mode configured for this branch
     *
     * @return the fast forward mode configured for this branch
     */
    public FastForwardMode getFastForwardMode() {
        return fastForwardMode;
    }

    /**
     * Whether merges into this branch are configured to be squash merges, false
     * otherwise
     *
     * @return true if merges into this branch are configured to be squash
     *         merges, false otherwise
     */
    public boolean isSquash() {
        return squash;
    }

    /**
     * Whether {@code --no-commit} option is not set.
     *
     * @return {@code false} if --no-commit is configured for this branch,
     *         {@code true} otherwise (even if --squash is configured)
     */
    public boolean isCommit() {
        return commit;
    }

    private static FastForwardMode getFastForwardMode(Config config,
            String[] mergeOptions) {
        for (String option : mergeOptions) {
            for (FastForwardMode mode : FastForwardMode.values())
                if (mode.matchConfigValue(option))
                    return mode;
        }
        FastForwardMode ffmode = FastForwardMode.valueOf(config.getEnum(
                ConfigConstants.CONFIG_KEY_MERGE, null,
                ConfigConstants.CONFIG_KEY_FF, FastForwardMode.Merge.TRUE));
        return ffmode;
    }

    private static boolean isMergeConfigOptionSet(String optionToLookFor,
            String[] mergeOptions) {
        for (String option : mergeOptions) {
            if (optionToLookFor.equals(option))
                return true;
        }
        return false;
    }

    private static String[] getMergeOptions(String branch, Config config) {
        String mergeOptions = config.getString(
                ConfigConstants.CONFIG_BRANCH_SECTION, branch,
                ConfigConstants.CONFIG_KEY_MERGEOPTIONS);
        if (mergeOptions != null) {
            return mergeOptions.split("\\s"); //$NON-NLS-1$
        }
        return new String[0];
    }

    private static class MergeConfigSectionParser implements
            SectionParser<MergeConfig> {

        private final String branch;

        public MergeConfigSectionParser(String branch) {
            this.branch = branch;
        }

        @Override
        public MergeConfig parse(Config cfg) {
            return new MergeConfig(branch, cfg);
        }

        @Override
        public boolean equals(Object obj) {
            if (obj instanceof MergeConfigSectionParser) {
                return branch.equals(((MergeConfigSectionParser) obj).branch);
            }
            return false;
        }

        @Override
        public int hashCode() {
            return branch.hashCode();
        }

    }

}