[core] keep tiles renderable even if a subsequent error occurs

Since 9a9408e8111bcdcd0fcb9a93112d61ab8fce0601, we marked tiles as non-renderable if an error occured. This lead to situations where a tile was loaded + parsed successfully, then a revalidation attempt occured (e.g. because the resource was stale) which failed. In this case, we used to mark the tile as non-renderable although we could've used the perfectly parsed (stale) resource.

1 files changed, 14 insertions, 0 deletions

diff --git a/test/tile/raster_tile.test.cpp b/test/tile/raster_tile.test.cpp
index e96e09bacf..efdc4767d9 100644
--- a/test/tile/raster_tile.test.cpp
+++ b/test/tile/raster_tile.test.cpp
@@ -66,6 +66,20 @@ TEST(RasterTile, onParsed) {
     EXPECT_TRUE(tile.isRenderable());
     EXPECT_TRUE(tile.isLoaded());
     EXPECT_TRUE(tile.isComplete());
+
+    // Make sure that once we've had a renderable tile and then receive erroneous data, we retain
+    // the previously rendered data and keep the tile renderable.
+    tile.setError(std::make_exception_ptr(std::runtime_error("Connection offline")));
+    EXPECT_TRUE(tile.isRenderable());
+    EXPECT_TRUE(tile.isLoaded());
+    EXPECT_TRUE(tile.isComplete());
+
+    // Then simulate a parsing failure and make sure that we keep it renderable in this situation
+    // as well.
+    tile.onError(std::make_exception_ptr(std::runtime_error("Parse error")), 0);
+    ASSERT_TRUE(tile.isRenderable());
+    EXPECT_TRUE(tile.isLoaded());
+    EXPECT_TRUE(tile.isComplete());
 }
 
 TEST(RasterTile, onParsedEmpty) {