jgit/org.eclipse.jgit/src/org/eclipse/jgit/diff/DiffConfig.java

/*
 * Copyright (C) 2010, Google Inc.
 * and other copyright owners as documented in the project's IP log.
 *
 * This program and the accompanying materials are made available
 * under the terms of the Eclipse Distribution License v1.0 which
 * accompanies this distribution, is reproduced below, and is
 * available at http://www.eclipse.org/org/documents/edl-v10.php
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 * without modification, are permitted provided that the following
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 * - Redistributions of source code must retain the above copyright
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package org.eclipse.jgit.diff;

import java.text.MessageFormat;

import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.Config;
import org.eclipse.jgit.lib.Config.SectionParser;
import org.eclipse.jgit.util.StringUtils;

/** Keeps track of diff related configuration options. */
public class DiffConfig {
	/** Key for {@link Config#get(SectionParser)}. */
	public static final Config.SectionParser<DiffConfig> KEY = new SectionParser<DiffConfig>() {
		public DiffConfig parse(final Config cfg) {
			return new DiffConfig(cfg);
		}
	};

	/** Permissible values for {@code diff.renames}. */
	public static enum RenameDetectionType {
		/** Rename detection is disabled. */
		FALSE,

		/** Rename detection is enabled. */
		TRUE,

		/** Copies should be detected too. */
		COPY
	}

	private final boolean noPrefix;

	private final RenameDetectionType renameDetectionType;

	private final int renameLimit;

	private DiffConfig(final Config rc) {
		noPrefix = rc.getBoolean("diff", "noprefix", false); //$NON-NLS-1$ //$NON-NLS-2$
		renameDetectionType = parseRenameDetectionType(rc.getString("diff", //$NON-NLS-1$
				null, "renames")); //$NON-NLS-1$
		renameLimit = rc.getInt("diff", "renamelimit", 200); //$NON-NLS-1$ //$NON-NLS-2$
	}

	/** @return true if the prefix "a/" and "b/" should be suppressed. */
	public boolean isNoPrefix() {
		return noPrefix;
	}

	/** @return true if rename detection is enabled by default. */
	public boolean isRenameDetectionEnabled() {
		return renameDetectionType != RenameDetectionType.FALSE;
	}

	/** @return type of rename detection to perform. */
	public RenameDetectionType getRenameDetectionType() {
		return renameDetectionType;
	}

	/** @return limit on number of paths to perform inexact rename detection. */
	public int getRenameLimit() {
		return renameLimit;
	}

	private static RenameDetectionType parseRenameDetectionType(
			final String renameString) {
		if (renameString == null)
			return RenameDetectionType.FALSE;
		else if (StringUtils.equalsIgnoreCase("copy", renameString) //$NON-NLS-1$
				|| StringUtils.equalsIgnoreCase("copies", renameString)) //$NON-NLS-1$
			return RenameDetectionType.COPY;
		else {
			final Boolean renameBoolean = StringUtils
					.toBooleanOrNull(renameString);
			if (renameBoolean == null)
				throw new IllegalArgumentException(MessageFormat.format(
						JGitText.get().enumValueNotSupported2, "diff", //$NON-NLS-1$
						"renames", renameString)); //$NON-NLS-1$
			else if (renameBoolean.booleanValue())
				return RenameDetectionType.TRUE;
			else
				return RenameDetectionType.FALSE;
		}
	}
}