Import: empty tracks cannot be imported as TrackStatistics cannot be restored.

#316.

src/androidTest/java/de/dennisguse/opentracks/io/file/importer/LegacyImportTest.java

@@ -83,6 +83,21 @@ public class LegacyImportTest {
         assertTrackpoint(importedTrackPoints.get(5), TrackPoint.Type.TRACKPOINT, "2020-11-28T17:07:20.870Z", 1.234046, 12.340082, 417.99432373046875);
     }
 
+    /**
+     * At least one valid location is required.
+     * Before v3.15.0, Tracks without TrackPoints could be created; such tracks cannot be imported as we cannot restore the TrackStatistics (especially startTime and stopTime).
+     */
+    @LargeTest
+    @Test(expected = ImportParserException.class)
+    public void kml_without_locations() {
+        // given
+        KmlFileTrackImporter trackImporter = new KmlFileTrackImporter(context);
+        InputStream inputStream = InstrumentationRegistry.getInstrumentation().getContext().getResources().openRawResource(de.dennisguse.opentracks.debug.test.R.raw.legacy_kml_empty);
+
+        // when
+        importTrackId = trackImporter.importFile(inputStream);
+    }
+
     /**
      * Check that data that contains pause (lat=100, lng=0) and resume (lat=200, lng=0) locations are restored to a segment break.
      */

src/androidTest/java/de/dennisguse/opentracks/stats/TrackStatisticsUpdaterTest.java

@@ -29,7 +29,7 @@ public class TrackStatisticsUpdaterTest {
         assertEquals(2.5, statistics.getMinElevation(), 0.01);
         assertEquals(27.5, statistics.getMaxElevation(), 0.01);
         assertEquals(18.0, statistics.getTotalElevationGain(), 0.01);
-        assertEquals(72.0, statistics.getTotalElevationLoss(), 0.01);
+        assertEquals(18.0, statistics.getTotalElevationLoss(), 0.01);
 
         assertEquals(14.226, statistics.getMaxSpeed(), 0.01);
         assertEquals(14.226, statistics.getAverageMovingSpeed(), 0.01);