[core] make sure tiles are not treated as complete until all worker operations completed

Previously, when we started a worker operation that eventually throws an exception (e.g. due to the tile not being parseable), and then enqueue another worker operation while the first one is processing, we treated the worker as idle once the first operation's error callback fired, even though the second operation was still in progress. Due to our use of coalescing, I was unable to come up with a reliable test since we'd need to reproduce the behavior described above, which is timing dependent.

11 files changed, 57 insertions, 51 deletions

diff --git a/src/mbgl/tile/geometry_tile.cpp b/src/mbgl/tile/geometry_tile.cpp
index c4d5d3bae3..23b3737a38 100644
--- a/src/mbgl/tile/geometry_tile.cpp
+++ b/src/mbgl/tile/geometry_tile.cpp
@@ -116,9 +116,10 @@ void GeometryTile::redoLayout() {
     worker.invoke(&GeometryTileWorker::setLayers, std::move(copy), correlationID);
 }
 
-void GeometryTile::onLayout(LayoutResult result) {
+void GeometryTile::onLayout(LayoutResult result, const uint64_t resultCorrelationID) {
     loaded = true;
     renderable = true;
+    (void)resultCorrelationID;
     nonSymbolBuckets = std::move(result.nonSymbolBuckets);
     featureIndex = std::move(result.featureIndex);
     data = std::move(result.tileData);
@@ -126,10 +127,10 @@ void GeometryTile::onLayout(LayoutResult result) {
     observer->onTileChanged(*this);
 }
 
-void GeometryTile::onPlacement(PlacementResult result) {
+void GeometryTile::onPlacement(PlacementResult result, const uint64_t resultCorrelationID) {
     loaded = true;
     renderable = true;
-    if (result.correlationID == correlationID) {
+    if (resultCorrelationID == correlationID) {
         pending = false;
     }
     symbolBuckets = std::move(result.symbolBuckets);
@@ -140,9 +141,11 @@ void GeometryTile::onPlacement(PlacementResult result) {
     observer->onTileChanged(*this);
 }
 
-void GeometryTile::onError(std::exception_ptr err) {
+void GeometryTile::onError(std::exception_ptr err, const uint64_t resultCorrelationID) {
     loaded = true;
-    pending = false;
+    if (resultCorrelationID == correlationID) {
+        pending = false;
+    }
     observer->onTileError(*this, err);
 }
     
diff --git a/src/mbgl/tile/geometry_tile.hpp b/src/mbgl/tile/geometry_tile.hpp
index ed5d8d87bf..910cb446a0 100644
--- a/src/mbgl/tile/geometry_tile.hpp
+++ b/src/mbgl/tile/geometry_tile.hpp
@@ -68,19 +68,17 @@ public:
         std::unordered_map<std::string, std::shared_ptr<Bucket>> nonSymbolBuckets;
         std::unique_ptr<FeatureIndex> featureIndex;
         std::unique_ptr<GeometryTileData> tileData;
-        uint64_t correlationID;
     };
-    void onLayout(LayoutResult);
+    void onLayout(LayoutResult, uint64_t correlationID);
 
     class PlacementResult {
     public:
         std::unordered_map<std::string, std::shared_ptr<Bucket>> symbolBuckets;
         std::unique_ptr<CollisionTile> collisionTile;
-        uint64_t correlationID;
     };
-    void onPlacement(PlacementResult);
+    void onPlacement(PlacementResult, uint64_t correlationID);
 
-    void onError(std::exception_ptr);
+    void onError(std::exception_ptr, uint64_t correlationID);
     
 protected:
     const GeometryTileData* getData() {
diff --git a/src/mbgl/tile/geometry_tile_worker.cpp b/src/mbgl/tile/geometry_tile_worker.cpp
index 616a0bba1f..25834914c4 100644
--- a/src/mbgl/tile/geometry_tile_worker.cpp
+++ b/src/mbgl/tile/geometry_tile_worker.cpp
@@ -88,7 +88,7 @@ void GeometryTileWorker::setData(std::unique_ptr<const GeometryTileData> data_,
             break;
         }
     } catch (...) {
-        parent.invoke(&GeometryTile::onError, std::current_exception());
+        parent.invoke(&GeometryTile::onError, std::current_exception(), correlationID);
     }
 }
 
@@ -112,7 +112,7 @@ void GeometryTileWorker::setLayers(std::vector<std::unique_ptr<Layer>> layers_,
             break;
         }
     } catch (...) {
-        parent.invoke(&GeometryTile::onError, std::current_exception());
+        parent.invoke(&GeometryTile::onError, std::current_exception(), correlationID);
     }
 }
 
@@ -136,7 +136,7 @@ void GeometryTileWorker::setPlacementConfig(PlacementConfig placementConfig_, ui
             break;
         }
     } catch (...) {
-        parent.invoke(&GeometryTile::onError, std::current_exception());
+        parent.invoke(&GeometryTile::onError, std::current_exception(), correlationID);
     }
 }
 
@@ -161,7 +161,7 @@ void GeometryTileWorker::symbolDependenciesChanged() {
             break;
         }
     } catch (...) {
-        parent.invoke(&GeometryTile::onError, std::current_exception());
+        parent.invoke(&GeometryTile::onError, std::current_exception(), correlationID);
     }
 }
 
@@ -187,7 +187,7 @@ void GeometryTileWorker::coalesced() {
             break;
         }
     } catch (...) {
-        parent.invoke(&GeometryTile::onError, std::current_exception());
+        parent.invoke(&GeometryTile::onError, std::current_exception(), correlationID);
     }
 }
 
@@ -353,8 +353,7 @@ void GeometryTileWorker::redoLayout() {
         std::move(buckets),
         std::move(featureIndex),
         *data ? (*data)->clone() : nullptr,
-        correlationID
-    });
+    }, correlationID);
 
     attemptPlacement();
 }
@@ -409,9 +408,8 @@ void GeometryTileWorker::attemptPlacement() {
 
     parent.invoke(&GeometryTile::onPlacement, GeometryTile::PlacementResult {
         std::move(buckets),
-        std::move(collisionTile),
-        correlationID
-    });
+        std::move(collisionTile),        
+    }, correlationID);
 }
 
 } // namespace mbgl
diff --git a/src/mbgl/tile/raster_tile.cpp b/src/mbgl/tile/raster_tile.cpp
index 770561e703..12dfaf87d4 100644
--- a/src/mbgl/tile/raster_tile.cpp
+++ b/src/mbgl/tile/raster_tile.cpp
@@ -37,18 +37,27 @@ void RasterTile::setData(std::shared_ptr<const std::string> data,
                              optional<Timestamp> expires_) {
     modified = modified_;
     expires = expires_;
-    worker.invoke(&RasterTileWorker::parse, data);
+
+    pending = true;
+    ++correlationID;
+    worker.invoke(&RasterTileWorker::parse, data, correlationID);
 }
 
-void RasterTile::onParsed(std::unique_ptr<Bucket> result) {
+void RasterTile::onParsed(std::unique_ptr<Bucket> result, const uint64_t resultCorrelationID) {
     bucket = std::move(result);
     loaded = true;
+    if (resultCorrelationID == correlationID) {
+        pending = false;
+    }
     renderable = bucket ? true : false;
     observer->onTileChanged(*this);
 }
 
-void RasterTile::onError(std::exception_ptr err) {
+void RasterTile::onError(std::exception_ptr err, const uint64_t resultCorrelationID) {
     loaded = true;
+    if (resultCorrelationID == correlationID) {
+        pending = false;
+    }
     observer->onTileError(*this, err);
 }
 
diff --git a/src/mbgl/tile/raster_tile.hpp b/src/mbgl/tile/raster_tile.hpp
index e047430485..28fcb554a9 100644
--- a/src/mbgl/tile/raster_tile.hpp
+++ b/src/mbgl/tile/raster_tile.hpp
@@ -31,8 +31,8 @@ public:
     void cancel() override;
     Bucket* getBucket(const RenderLayer&) const override;
 
-    void onParsed(std::unique_ptr<Bucket> result);
-    void onError(std::exception_ptr);
+    void onParsed(std::unique_ptr<Bucket> result, uint64_t correlationID);
+    void onError(std::exception_ptr, uint64_t correlationID);
 
 private:
     TileLoader<RasterTile> loader;
@@ -40,6 +40,8 @@ private:
     std::shared_ptr<Mailbox> mailbox;
     Actor<RasterTileWorker> worker;
 
+    uint64_t correlationID = 0;
+
     // Contains the Bucket object for the tile. Buckets are render
     // objects and they get added by tile parsing operations.
     std::unique_ptr<Bucket> bucket;
diff --git a/src/mbgl/tile/raster_tile_worker.cpp b/src/mbgl/tile/raster_tile_worker.cpp
index 8c1fc2f673..585fe5ec95 100644
--- a/src/mbgl/tile/raster_tile_worker.cpp
+++ b/src/mbgl/tile/raster_tile_worker.cpp
@@ -10,17 +10,17 @@ RasterTileWorker::RasterTileWorker(ActorRef<RasterTileWorker>, ActorRef<RasterTi
     : parent(std::move(parent_)) {
 }
 
-void RasterTileWorker::parse(std::shared_ptr<const std::string> data) {
+void RasterTileWorker::parse(std::shared_ptr<const std::string> data, uint64_t correlationID) {
     if (!data) {
-        parent.invoke(&RasterTile::onParsed, nullptr); // No data; empty tile.
+        parent.invoke(&RasterTile::onParsed, nullptr, correlationID); // No data; empty tile.
         return;
     }
 
     try {
         auto bucket = std::make_unique<RasterBucket>(util::unpremultiply(decodeImage(*data)));
-        parent.invoke(&RasterTile::onParsed, std::move(bucket));
+        parent.invoke(&RasterTile::onParsed, std::move(bucket), correlationID);
     } catch (...) {
-        parent.invoke(&RasterTile::onError, std::current_exception());
+        parent.invoke(&RasterTile::onError, std::current_exception(), correlationID);
     }
 }
 
diff --git a/src/mbgl/tile/raster_tile_worker.hpp b/src/mbgl/tile/raster_tile_worker.hpp
index 44bc37ca5d..520973c3c3 100644
--- a/src/mbgl/tile/raster_tile_worker.hpp
+++ b/src/mbgl/tile/raster_tile_worker.hpp
@@ -13,7 +13,7 @@ class RasterTileWorker {
 public:
     RasterTileWorker(ActorRef<RasterTileWorker>, ActorRef<RasterTile>);
 
-    void parse(std::shared_ptr<const std::string> data);
+    void parse(std::shared_ptr<const std::string> data, uint64_t correlationID);
 
 private:
     ActorRef<RasterTile> parent;
diff --git a/test/tile/annotation_tile.test.cpp b/test/tile/annotation_tile.test.cpp
index 4d71c5b0b4..ac3e064c50 100644
--- a/test/tile/annotation_tile.test.cpp
+++ b/test/tile/annotation_tile.test.cpp
@@ -52,8 +52,7 @@ TEST(AnnotationTile, Issue8289) {
         {},
             std::make_unique<FeatureIndex>(),
             std::move(data),
-            0
-    });
+    }, 0);
 
     auto collisionTile = std::make_unique<CollisionTile>(PlacementConfig());
 
@@ -65,16 +64,14 @@ TEST(AnnotationTile, Issue8289) {
     tile.onPlacement(GeometryTile::PlacementResult {
         {},
             std::move(collisionTile),
-            0
-    });
+    }, 0);
 
     // Simulate a second layout with empty data.
     tile.onLayout(GeometryTile::LayoutResult {
         {},
             std::make_unique<FeatureIndex>(),
             std::make_unique<AnnotationTileData>(),
-            0
-    });
+    }, 0);
 
     std::unordered_map<std::string, std::vector<Feature>> result;
     GeometryCoordinates queryGeometry {{ Point<int16_t>(0, 0) }};
diff --git a/test/tile/geojson_tile.test.cpp b/test/tile/geojson_tile.test.cpp
index 80e215a98d..18d11c2c14 100644
--- a/test/tile/geojson_tile.test.cpp
+++ b/test/tile/geojson_tile.test.cpp
@@ -76,7 +76,7 @@ TEST(GeoJSONTile, Issue7648) {
 TEST(GeoJSONTile, Issue9927) {
     GeoJSONTileTest test;
 
-    CircleLayer layer("circle", "source");
+    test.style.addLayer(std::make_unique<CircleLayer>("circle", "source"));
 
     mapbox::geometry::feature_collection<int16_t> features;
     features.push_back(mapbox::geometry::feature<int16_t> {
@@ -85,7 +85,6 @@ TEST(GeoJSONTile, Issue9927) {
 
     GeoJSONTile tile(OverscaledTileID(0, 0, 0), "source", test.tileParameters, features);
 
-    tile.setLayers({{ layer.baseImpl }});
     tile.setPlacementConfig({});
 
     while (!tile.isComplete()) {
@@ -93,17 +92,18 @@ TEST(GeoJSONTile, Issue9927) {
     }
 
     ASSERT_TRUE(tile.isRenderable());
-    ASSERT_NE(nullptr, tile.getBucket(*layer.baseImpl));
+    ASSERT_NE(nullptr, tile.getBucket(*test.style.getRenderLayer("circle")));
 
     // 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")));
     ASSERT_TRUE(tile.isRenderable());
-    ASSERT_NE(nullptr, tile.getBucket(*layer.baseImpl));
+    ASSERT_NE(nullptr, tile.getBucket(*test.style.getRenderLayer("circle")));
 
     // 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")));
+    // as well. We're using 3 as a correlationID since we've done two three calls that increment
+    // this counter (as part of the GeoJSONTile constructor, setLayers, and setPlacementConfig).
+    tile.onError(std::make_exception_ptr(std::runtime_error("Parse error")), 3);
     ASSERT_TRUE(tile.isRenderable());
-    ASSERT_NE(nullptr, tile.getBucket(*layer.baseImpl));
+    ASSERT_NE(nullptr, tile.getBucket(*test.style.getRenderLayer("circle")));
  }
diff --git a/test/tile/raster_tile.test.cpp b/test/tile/raster_tile.test.cpp
index 596f97884c..a606066e9b 100644
--- a/test/tile/raster_tile.test.cpp
+++ b/test/tile/raster_tile.test.cpp
@@ -47,7 +47,7 @@ TEST(RasterTile, setError) {
 TEST(RasterTile, onError) {
     RasterTileTest test;
     RasterTile tile(OverscaledTileID(0, 0, 0), test.tileParameters, test.tileset);
-    tile.onError(std::make_exception_ptr(std::runtime_error("test")));
+    tile.onError(std::make_exception_ptr(std::runtime_error("test")), 0);
     EXPECT_FALSE(tile.isRenderable());
     EXPECT_TRUE(tile.isLoaded());
     EXPECT_TRUE(tile.isComplete());
@@ -56,7 +56,7 @@ TEST(RasterTile, onError) {
 TEST(RasterTile, onParsed) {
     RasterTileTest test;
     RasterTile tile(OverscaledTileID(0, 0, 0), test.tileParameters, test.tileset);
-    tile.onParsed(std::make_unique<RasterBucket>(UnassociatedImage{}));
+    tile.onParsed(std::make_unique<RasterBucket>(UnassociatedImage{}), 0);
     EXPECT_TRUE(tile.isRenderable());
     EXPECT_TRUE(tile.isLoaded());
     EXPECT_TRUE(tile.isComplete());
@@ -79,7 +79,7 @@ TEST(RasterTile, onParsed) {
 TEST(RasterTile, onParsedEmpty) {
     RasterTileTest test;
     RasterTile tile(OverscaledTileID(0, 0, 0), test.tileParameters, test.tileset);
-    tile.onParsed(nullptr);
+    tile.onParsed(nullptr, 0);
     EXPECT_FALSE(tile.isRenderable());
     EXPECT_TRUE(tile.isLoaded());
     EXPECT_TRUE(tile.isComplete());
diff --git a/test/tile/vector_tile.test.cpp b/test/tile/vector_tile.test.cpp
index 37bfe8512d..336076ecc2 100644
--- a/test/tile/vector_tile.test.cpp
+++ b/test/tile/vector_tile.test.cpp
@@ -53,7 +53,8 @@ TEST(VectorTile, setError) {
 TEST(VectorTile, onError) {
     VectorTileTest test;
     VectorTile tile(OverscaledTileID(0, 0, 0), "source", test.tileParameters, test.tileset);
-    tile.onError(std::make_exception_ptr(std::runtime_error("test")));
+    tile.onError(std::make_exception_ptr(std::runtime_error("test")), 0);
+
     EXPECT_FALSE(tile.isRenderable());
     EXPECT_TRUE(tile.isLoaded());
     EXPECT_TRUE(tile.isComplete());
@@ -78,16 +79,14 @@ TEST(VectorTile, Issue7615) {
             symbolBucket
         }},
         nullptr,
-        0
-    });
+    }, 0);
 
     // Subsequent onLayout should not cause the existing symbol bucket to be discarded.
     tile.onLayout(GeometryTile::LayoutResult {
         {},
         nullptr,
         nullptr,
-        0
-    });
+    }, 0);
 
     EXPECT_EQ(symbolBucket.get(), tile.getBucket(*symbolLayer.baseImpl->createRenderLayer()));
 }