Make sure the migrations are ordered correctly

src/main/java/dk/nsi/sdm4/core/persistence/migration/Migration.java

@@ -17,6 +17,13 @@ public class Migration implements Comparable<Migration> {
 
 	private static final Pattern migrationNamePattern = Pattern.compile(".*/?V(\\d{8}_\\d{4})__(.*).sql");
 
+	protected Migration(String version, String description, Resource sqlSource) {
+		// used for testing
+		this.version = version;
+		this.description = description;
+		this.sqlSource = sqlSource;
+	}
+
 	public Migration(Resource sqlSource) {
 		this.sqlSource = sqlSource;
 		parseResourcename();

src/test/java/dk/nsi/sdm4/core/persistence/migration/MigrationComparableTest.java

@@ -1,10 +1,45 @@
 package dk.nsi.sdm4.core.persistence.migration;
 
+import org.junit.Before;
 import org.junit.Test;
 
+import static org.junit.Assert.assertTrue;
+
 public class MigrationComparableTest {
+	private Migration migration2;
+	private Migration migration1;
+	private Migration migration3;
+	private Migration migrationTime1;
+	private Migration migrationTime2;
+
+	@Before
+	public void setup() {
+		migration1 = new Migration("20120728_0101", null, null);
+		migration2 = new Migration("20120828_0101", null, null);
+		migration3 = new Migration("20120901_0101", null, null);
+
+		migrationTime1 = new Migration("20120901_0101", null, null);
+		migrationTime2 = new Migration("20120901_0102", null, null);
+	}
+
+
+	@Test
+	public void comparesDifferentMonthsCorrectly() {
+		assertTrue(migration1.compareTo(migration2) < 0);
+	}
+
 	@Test
-	public void comparesTheVersionsAsDates() {
+	public void doesNotJustUseTheDayOfMonth() {
+		assertTrue(migration2.compareTo(migration3) < 0);
+	}
 
+	@Test
+	public void canCrossSeveralMonths() {
+		assertTrue(migration3.compareTo(migration1) > 0);
+	}
+
+	@Test
+	public void understandsTimestampPartOfVersion() {
+		assertTrue(migrationTime1.compareTo(migrationTime2) < 0);
 	}
 }