Don't crash while parsing ignore patterns

Catch unexpected PatternSyntaxException and convert it to
InvalidPatternException. Log such errors, do not silently ignore them.

Bug: 463581
Change-Id: Id0936d9816769ec0cfae1898beda0f7a3c146e67
Signed-off-by: Andrey Loskutov <loskutov@gmx.de>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit/resources/org/eclipse/jgit/internal/JGitText.properties

@@ -328,6 +328,7 @@ invalidId=Invalid id: {0}
 invalidId0=Invalid id
 invalidIdLength=Invalid id length {0}; should be {1}
 invalidIgnoreParamSubmodule=Found invalid ignore param for submodule {0}.
+invalidIgnoreRule=Exception caught while parsing ignore rule ''{0}''.
 invalidIntegerValue=Invalid integer value: {0}.{1}={2}
 invalidKey=Invalid key: {0}
 invalidLineInConfigFile=Invalid line in config file

org.eclipse.jgit/src/org/eclipse/jgit/ignore/FastIgnoreRule.java

@@ -47,6 +47,8 @@ import static org.eclipse.jgit.ignore.internal.IMatcher.NO_MATCH;
 import org.eclipse.jgit.errors.InvalidPatternException;
 import org.eclipse.jgit.ignore.internal.IMatcher;
 import org.eclipse.jgit.ignore.internal.PathMatcher;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * "Fast" (compared with IgnoreRule) git ignore rule implementation supporting
@@ -57,6 +59,8 @@ import org.eclipse.jgit.ignore.internal.PathMatcher;
  * @since 3.6
  */
 public class FastIgnoreRule {
+	private final static Logger LOG = LoggerFactory
+			.getLogger(FastIgnoreRule.class);
 
 	/**
 	 * Character used as default path separator for ignore entries
@@ -121,6 +125,7 @@ public class FastIgnoreRule {
 					Character.valueOf(PATH_SEPARATOR), dirOnly);
 		} catch (InvalidPatternException e) {
 			m = NO_MATCH;
+			LOG.error(e.getMessage(), e);
 		}
 		this.matcher = m;
 	}

org.eclipse.jgit/src/org/eclipse/jgit/ignore/internal/Strings.java

@@ -44,13 +44,16 @@ package org.eclipse.jgit.ignore.internal;
 
 import static java.lang.Character.isLetter;
 
+import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.regex.Pattern;
+import java.util.regex.PatternSyntaxException;
 
 import org.eclipse.jgit.errors.InvalidPatternException;
 import org.eclipse.jgit.ignore.FastIgnoreRule;
+import org.eclipse.jgit.internal.JGitText;
 
 /**
  * Various {@link String} related utility methods, written mostly to avoid
@@ -367,7 +370,16 @@ public class Strings {
 
 		if (in_brackets > 0)
 			throw new InvalidPatternException("Not closed bracket?", pattern); //$NON-NLS-1$
+		try {
 			return Pattern.compile(sb.toString());
+		} catch (PatternSyntaxException e) {
+			InvalidPatternException patternException = new InvalidPatternException(
+					MessageFormat.format(JGitText.get().invalidIgnoreRule,
+							pattern),
+					pattern);
+			patternException.initCause(e);
+			throw patternException;
+		}
 	}
 
 	/**

org.eclipse.jgit/src/org/eclipse/jgit/internal/JGitText.java

@@ -387,6 +387,7 @@ public class JGitText extends TranslationBundle {
 	/***/ public String invalidId0;
 	/***/ public String invalidIdLength;
 	/***/ public String invalidIgnoreParamSubmodule;
+	/***/ public String invalidIgnoreRule;
 	/***/ public String invalidIntegerValue;
 	/***/ public String invalidKey;
 	/***/ public String invalidLineInConfigFile;