Fix DiffConfig to understand "copy" resp. "copies" for diff.renames property.refs/changes/48/1948/3

Rename detection should be considered enabled if
diff.renames config property is set to "copy" or "copies", instead of
throwing IllegalArgumentException.

Change-Id: If55d955e37235d4d00f5b0febd6aa10c0e27814e

2 files changed, 79 insertions, 19 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/diff/DiffConfig.java b/org.eclipse.jgit/src/org/eclipse/jgit/diff/DiffConfig.java
index 4b86f55..436e606 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/diff/DiffConfig.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/diff/DiffConfig.java
@@ -43,8 +43,12 @@
 
 package org.eclipse.jgit.diff;
 
+import java.text.MessageFormat;
+
+import org.eclipse.jgit.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 {
@@ -55,15 +59,28 @@ public class DiffConfig {
 		}
 	};
 
+	/** 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 boolean renames;
+	private final RenameDetectionType renameDetectionType;
 
 	private final int renameLimit;
 
 	private DiffConfig(final Config rc) {
 		noPrefix = rc.getBoolean("diff", "noprefix", false);
-		renames = rc.getBoolean("diff", "renames", false);
+		renameDetectionType = parseRenameDetectionType(rc.getString("diff",
+				null, "renames"));
 		renameLimit = rc.getInt("diff", "renamelimit", 200);
 	}
 
@@ -74,11 +91,37 @@ public class DiffConfig {
 
 	/** @return true if rename detection is enabled by default. */
 	public boolean isRenameDetectionEnabled() {
-		return renames;
+		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)
+				|| StringUtils.equalsIgnoreCase("copies", renameString))
+			return RenameDetectionType.COPY;
+		else {
+			final Boolean renameBoolean = StringUtils
+					.toBooleanOrNull(renameString);
+			if (renameBoolean == null)
+				throw new IllegalArgumentException(MessageFormat.format(
+						JGitText.get().enumValueNotSupported2, "diff",
+						"renames", renameString));
+			else if (renameBoolean.booleanValue())
+				return RenameDetectionType.TRUE;
+			else
+				return RenameDetectionType.FALSE;
+		}
+	}
 }
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/StringUtils.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/StringUtils.java
index 3759a12..59f3d83 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/StringUtils.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/StringUtils.java
@@ -121,6 +121,28 @@ public final class StringUtils {
 	}
 
 	/**
+	 * Parse a string as a standard Git boolean value. See
+	 * {@link #toBooleanOrNull(String)}.
+	 *
+	 * @param stringValue
+	 *            the string to parse.
+	 * @return the boolean interpretation of {@code value}.
+	 * @throws IllegalArgumentException
+	 *             if {@code value} is not recognized as one of the standard
+	 *             boolean names.
+	 */
+	public static boolean toBoolean(final String stringValue) {
+		if (stringValue == null)
+			throw new NullPointerException(JGitText.get().expectedBooleanStringValue);
+
+		final Boolean bool = toBooleanOrNull(stringValue);
+		if (bool == null)
+			throw new IllegalArgumentException(MessageFormat.format(JGitText.get().notABoolean, stringValue));
+
+		return bool.booleanValue();
+	}
+
+	/**
 	 * Parse a string as a standard Git boolean value.
 	 * <p>
 	 * The terms {@code yes}, {@code true}, {@code 1}, {@code on} can all be
@@ -133,30 +155,25 @@ public final class StringUtils {
 	 *
 	 * @param stringValue
 	 *            the string to parse.
-	 * @return the boolean interpretation of {@code value}.
-	 * @throws IllegalArgumentException
-	 *             if {@code value} is not recognized as one of the standard
-	 *             boolean names.
+	 * @return the boolean interpretation of {@code value} or null in case the
+	 *         string does not represent a boolean value
 	 */
-	public static boolean toBoolean(final String stringValue) {
+	public static Boolean toBooleanOrNull(final String stringValue) {
 		if (stringValue == null)
-			throw new NullPointerException(JGitText.get().expectedBooleanStringValue);
+			return null;
 
 		if (equalsIgnoreCase("yes", stringValue)
 				|| equalsIgnoreCase("true", stringValue)
 				|| equalsIgnoreCase("1", stringValue)
-				|| equalsIgnoreCase("on", stringValue)) {
-			return true;
-
-		} else if (equalsIgnoreCase("no", stringValue)
+				|| equalsIgnoreCase("on", stringValue))
+			return Boolean.TRUE;
+		else if (equalsIgnoreCase("no", stringValue)
 				|| equalsIgnoreCase("false", stringValue)
 				|| equalsIgnoreCase("0", stringValue)
-				|| equalsIgnoreCase("off", stringValue)) {
-			return false;
-
-		} else {
-			throw new IllegalArgumentException(MessageFormat.format(JGitText.get().notABoolean, stringValue));
-		}
+				|| equalsIgnoreCase("off", stringValue))
+			return Boolean.FALSE;
+		else
+			return null;
 	}
 
 	/**