[core] Add snapshotter unit tests

4 files changed, 151 insertions, 2 deletions

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 75d5ee3ef8..0248582c61 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -105,6 +105,17 @@ add_library(
     ${PROJECT_SOURCE_DIR}/test/util/url.test.cpp
 )
 
+# MapSnapshotter uses headless backend that is rendering image on a background thread. QT / macOS adaptation for headless backend creates
+# new window and updates it's parameters, which is not allowed since macOS mohave 10.14. Following block disables snapshotter unit tests for
+# QT on macOS. https://github.com/mapbox/mapbox-gl-native/issues/16267
+if(NOT (MBGL_WITH_QT AND CMAKE_SYSTEM_NAME STREQUAL Darwin))
+    target_sources(
+        mbgl-test
+        PRIVATE
+            ${PROJECT_SOURCE_DIR}/platform/default/src/mbgl/map/map_snapshotter.cpp ${PROJECT_SOURCE_DIR}/test/map/map_snapshotter.test.cpp
+    )
+endif()
+
 if(MBGL_WITH_OPENGL)
     target_sources(
         mbgl-test
diff --git a/test/fixtures/map/map_snapshotter_overlay/expected.png b/test/fixtures/map/map_snapshotter_overlay/expected.png
new file mode 100644
index 0000000000..cf45c80237
--- /dev/null
+++ b/test/fixtures/map/map_snapshotter_overlay/expected.png
diff --git a/test/fixtures/map/online/style.json b/test/fixtures/map/online/style.json
index 9543c477aa..921023526c 100644
--- a/test/fixtures/map/online/style.json
+++ b/test/fixtures/map/online/style.json
@@ -12,7 +12,7 @@
     "id": "background",
     "type": "background",
     "paint": {
-      "background-color": "red"
+      "background-color": "green"
     }
   }, {
     "id": "water",
@@ -20,7 +20,7 @@
     "source": "mapbox",
     "source-layer": "water",
     "paint": {
-      "fill-pattern": "noise",
+      "fill-pattern": "a",
       "fill-antialias": false
     }
   }]
diff --git a/test/map/map_snapshotter.test.cpp b/test/map/map_snapshotter.test.cpp
new file mode 100644
index 0000000000..9d8eae8892
--- /dev/null
+++ b/test/map/map_snapshotter.test.cpp
@@ -0,0 +1,138 @@
+#include <mbgl/map/camera.hpp>
+#include <mbgl/map/map_snapshotter.hpp>
+#include <mbgl/storage/resource_options.hpp>
+#include <mbgl/style/layers/fill_layer.hpp>
+#include <mbgl/style/style.hpp>
+#include <mbgl/test/util.hpp>
+#include <mbgl/util/run_loop.hpp>
+#include <mbgl/util/timer.hpp>
+
+using namespace mbgl;
+
+class SnapshotterObserver final : public MapSnapshotterObserver {
+public:
+    ~SnapshotterObserver() = default;
+    void onDidFinishLoadingStyle() override {
+        if (didFinishLoadingStyleCallback) {
+            didFinishLoadingStyleCallback();
+        }
+    }
+    std::function<void()> didFinishLoadingStyleCallback;
+};
+
+TEST(MapSnapshotter, setStyleJSON) {
+    util::RunLoop runLoop;
+    MapSnapshotter snapshotter(Size{32, 16}, 1.0f, ResourceOptions());
+    snapshotter.setStyleJSON(R"JSON({
+        "version": 8,
+        "layers": [{
+            "id": "background",
+            "type": "background",
+            "paint": {"background-color": "green"}
+        }]
+    })JSON");
+
+    snapshotter.snapshot([&runLoop](std::exception_ptr ptr,
+                                    mbgl::PremultipliedImage image,
+                                    mbgl::MapSnapshotter::Attributions,
+                                    mbgl::MapSnapshotter::PointForFn,
+                                    mbgl::MapSnapshotter::LatLngForFn) {
+        EXPECT_EQ(nullptr, ptr);
+        EXPECT_EQ(32, image.size.width);
+        EXPECT_EQ(16, image.size.height);
+        runLoop.stop();
+    });
+
+    runLoop.run();
+}
+
+TEST(MapSnapshotter, setSize) {
+    util::RunLoop runLoop;
+    MapSnapshotter snapshotter(Size{32, 16}, 1.0f, ResourceOptions());
+    snapshotter.setStyleJSON(R"JSON({
+        "version": 8,
+        "layers": [{
+            "id": "background",
+            "type": "background",
+            "paint": {"background-color": "green"}
+        }]
+    })JSON");
+
+    snapshotter.setSize(Size{16, 32});
+
+    snapshotter.snapshot([&runLoop](std::exception_ptr ptr,
+                                    mbgl::PremultipliedImage image,
+                                    mbgl::MapSnapshotter::Attributions,
+                                    mbgl::MapSnapshotter::PointForFn,
+                                    mbgl::MapSnapshotter::LatLngForFn) {
+        EXPECT_EQ(nullptr, ptr);
+        EXPECT_EQ(16, image.size.width);
+        EXPECT_EQ(32, image.size.height);
+        runLoop.stop();
+    });
+
+    runLoop.run();
+}
+
+TEST(MapSnapshotter, TEST_REQUIRES_SERVER(setStyleURL)) {
+    util::RunLoop runLoop;
+    MapSnapshotter snapshotter(Size{64, 32}, 1.0f, ResourceOptions());
+    snapshotter.setStyleURL("http://127.0.0.1:3000/online/style.json");
+    snapshotter.snapshot([&runLoop](std::exception_ptr ptr,
+                                    mbgl::PremultipliedImage image,
+                                    mbgl::MapSnapshotter::Attributions,
+                                    mbgl::MapSnapshotter::PointForFn,
+                                    mbgl::MapSnapshotter::LatLngForFn) {
+        EXPECT_EQ(nullptr, ptr);
+        EXPECT_EQ(64, image.size.width);
+        EXPECT_EQ(32, image.size.height);
+        runLoop.stop();
+    });
+
+    runLoop.run();
+}
+
+TEST(MapSnapshotter, TEST_REQUIRES_SERVER(cancel)) {
+    util::RunLoop runLoop;
+    MapSnapshotter snapshotter(Size{1, 1}, 1.0f, ResourceOptions());
+    snapshotter.setStyleURL("http://127.0.0.1:3000/online/style.json");
+    snapshotter.snapshot([](std::exception_ptr,
+                            mbgl::PremultipliedImage,
+                            mbgl::MapSnapshotter::Attributions,
+                            mbgl::MapSnapshotter::PointForFn,
+                            mbgl::MapSnapshotter::LatLngForFn) { ASSERT_TRUE(false); });
+
+    snapshotter.cancel();
+
+    util::Timer timer;
+    timer.start(Milliseconds(100), Duration::zero(), [&runLoop] { runLoop.stop(); });
+
+    runLoop.run();
+}
+
+TEST(MapSnapshotter, TEST_REQUIRES_SERVER(runtimeStyling)) {
+    util::RunLoop runLoop;
+    SnapshotterObserver observer;
+    MapSnapshotter snapshotter(Size{256, 128}, 1.0f, ResourceOptions(), observer);
+    snapshotter.setStyleURL("http://127.0.0.1:3000/online/style.json");
+
+    observer.didFinishLoadingStyleCallback = [&snapshotter, &runLoop] {
+        auto fillLayer = std::make_unique<style::FillLayer>("green_fill", "mapbox");
+        fillLayer->setSourceLayer("water");
+        fillLayer->setFillColor(Color(0.25, 0.88, 0.82, 1.0));
+        snapshotter.getStyle().addLayer(std::move(fillLayer));
+        snapshotter.snapshot([&runLoop](std::exception_ptr ptr,
+                                        mbgl::PremultipliedImage image,
+                                        mbgl::MapSnapshotter::Attributions,
+                                        mbgl::MapSnapshotter::PointForFn,
+                                        mbgl::MapSnapshotter::LatLngForFn) {
+            EXPECT_EQ(nullptr, ptr);
+            EXPECT_EQ(256, image.size.width);
+            EXPECT_EQ(128, image.size.height);
+            test::checkImage("test/fixtures/map/map_snapshotter_overlay", image, 0.005, 0.1);
+            runLoop.stop();
+        });
+    };
+
+    runLoop.run();
+}