@Test
  void testZ15Fill() throws Exception {
    List<Coordinate> outerPoints = z14CoordinateList(
      -2, -2,
      2, -2,
      2, 2,
      -2, 2,
      -2, -2
    );

    var results = runWithReaderFeatures(
      Map.of("threads", "1", "maxzoom", "15"),
      List.of(
        newReaderFeature(newPolygon(
          outerPoints
        ), Map.of())
      ),
      (in, features) -> features.polygon("layer")
        .setZoomRange(15, 15)
        .setBufferPixels(4)
    );

    assertEquals(List.of(
      feature(newPolygon(tileFill(4)), Map.of())
    ), results.tiles.get(TileCoord.ofXYZ(Z15_TILES / 2, Z15_TILES / 2, 15)));
  }
In-memory tests with fake data and profiles to ensure all features work end-to-end.
planetiler-core/src/test/java/com/onthegomap/planetiler/PlanetilerTests.java