Add old filename to matcher

app/src/main/java/org/tasks/backup/BackupConstants.kt

@@ -10,7 +10,7 @@ object BackupConstants {
     const val EXPORT_FILE_NAME = "user.%s.json"
     const val BACKUP_FILE_NAME = "auto.%s.json"
 
-    private val MATCHER = Pattern.compile("""(auto|user)\.(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})\.json""")
+    private val MATCHER = Pattern.compile("""(auto|user)\.(\d{2,4})(\d{2})(\d{2})[T-](\d{2})(\d{2})\.json""")
 
     fun isBackupFile(name: String?) = name?.let { MATCHER.matcher(it).matches() } ?: false
 
@@ -32,7 +32,7 @@ object BackupConstants {
                 .takeIf { it.matches() }
                 ?.let {
                     DateTime(
-                            it.group(2)!!.toInt(),
+                            it.group(2)!!.toInt().let { y -> if (y > 2000) y else y + 2000 },
                             it.group(3)!!.toInt(),
                             it.group(4)!!.toInt(),
                             it.group(5)!!.toInt(),

app/src/test/java/org/tasks/backup/BackupConstantsTest.kt

@@ -1,6 +1,8 @@
 package org.tasks.backup
 
-import org.junit.Assert.*
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
 import org.junit.Test
 import org.tasks.time.DateTime
 
@@ -21,7 +23,7 @@ class BackupConstantsTest {
     }
 
     @Test
-    fun getTimestampFromAutoBackup() {
+    fun getTimestampFromAutoBackupTwoDigits() {
         assertEquals(
                 DateTime(2020, 9, 10, 15, 3).millis,
                 BackupConstants.getTimestampFromFilename("auto.200910-1503.json")
@@ -29,10 +31,26 @@ class BackupConstantsTest {
     }
 
     @Test
-    fun getTimestampFromUserBackup() {
+    fun getTimestampFromUserBackupTwoDigits() {
         assertEquals(
                 DateTime(2020, 9, 10, 15, 3).millis,
                 BackupConstants.getTimestampFromFilename("user.200910-1503.json")
         )
     }
+
+    @Test
+    fun getTimestampFromAutoBackup() {
+        assertEquals(
+                DateTime(2020, 9, 10, 15, 3).millis,
+                BackupConstants.getTimestampFromFilename("auto.20200910T1503.json")
+        )
+    }
+
+    @Test
+    fun getTimestampFromUserBackup() {
+        assertEquals(
+                DateTime(2020, 9, 10, 15, 3).millis,
+                BackupConstants.getTimestampFromFilename("user.20200910T1503.json")
+        )
+    }
 }