Make sure SystemReader is reset after test is run

Otherwise the MockSystemReader from the test setup is active for other
tests.

Change-Id: I7caf693bd692d06936e29efd4dc4aabb48c1c39b
Signed-off-by: Robin Stocker <robin@nibor.org>

org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/LocalDiskRepositoryTestCase.java

@@ -170,6 +170,8 @@ public abstract class LocalDiskRepositoryTestCase {
 			recursiveDelete(tmp, false, true);
 		if (tmp != null && !tmp.exists())
 			CleanupThread.removed(tmp);
+
+		SystemReader.setInstance(null);
 	}
 
 	/** Increment the {@link #author} and {@link #committer} times. */

org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/ConfigTest.java

@@ -68,12 +68,19 @@ import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.junit.MockSystemReader;
 import org.eclipse.jgit.util.FS;
 import org.eclipse.jgit.util.SystemReader;
+import org.junit.After;
 import org.junit.Test;
 
 /**
  * Test reading of git config
  */
 public class ConfigTest {
+
+	@After
+	public void tearDown() {
+		SystemReader.setInstance(null);
+	}
+
 	@Test
 	public void test001_ReadBareKey() throws ConfigInvalidException {
 		final Config c = parse("[foo]\nbar\n");

org.eclipse.jgit.test/tst/org/eclipse/jgit/util/GitDateFormatterTest.java

@@ -48,6 +48,7 @@ import static org.junit.Assert.assertEquals;
 import org.eclipse.jgit.junit.MockSystemReader;
 import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.util.GitDateFormatter.Format;
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -70,6 +71,11 @@ public class GitDateFormatterTest {
 				.parsePersonIdent("A U Thor <author@example.com> 1316560165 -0400");
 	}
 
+	@After
+	public void tearDown() {
+		SystemReader.setInstance(null);
+	}
+
 	@Test
 	public void DEFAULT() {
 		assertEquals("Tue Sep 20 19:09:25 2011 -0400", new GitDateFormatter(

org.eclipse.jgit.test/tst/org/eclipse/jgit/util/GitDateParserTest.java

@@ -50,6 +50,7 @@ import java.util.Date;
 import java.util.GregorianCalendar;
 
 import org.eclipse.jgit.junit.MockSystemReader;
+import org.junit.After;
 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;
@@ -61,6 +62,11 @@ public class GitDateParserTest {
 		SystemReader.setInstance(mockSystemReader);
 	}
 
+	@After
+	public void tearDown() {
+		SystemReader.setInstance(null);
+	}
+
 	@Test
 	public void yesterday() throws ParseException {
 		GregorianCalendar cal = new GregorianCalendar(SystemReader

org.eclipse.jgit.test/tst/org/eclipse/jgit/util/RelativeDateFormatterTest.java

@@ -53,6 +53,7 @@ import java.util.Date;
 
 import org.eclipse.jgit.junit.MockSystemReader;
 import org.eclipse.jgit.util.RelativeDateFormatter;
+import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -63,6 +64,11 @@ public class RelativeDateFormatterTest {
 		SystemReader.setInstance(new MockSystemReader());
 	}
 
+	@After
+	public void tearDown() {
+		SystemReader.setInstance(null);
+	}
+
 	private static void assertFormat(long ageFromNow, long timeUnit,
 			String expectedFormat) {
 		Date d = new Date(SystemReader.getInstance().getCurrentTime()

org.eclipse.jgit/src/org/eclipse/jgit/util/SystemReader.java

@@ -137,7 +137,8 @@ public abstract class SystemReader {
 
 	/**
 	 * @param newReader
-	 *            the new instance to use when accessing properties.
+	 *            the new instance to use when accessing properties, or null for
+	 *            the default instance.
 	 */
 	public static void setInstance(SystemReader newReader) {
 		if (newReader == null)