Always call onSourceLoaded observers (#15548)

* [core] add sources to source collection before triggering load

* [test] add testcase for #15514

* [core] also call onSourceLoaded observers when no network request was necessary

2 files changed, 51 insertions, 0 deletions

diff --git a/test/storage/sync_file_source.test.cpp b/test/storage/sync_file_source.test.cpp
new file mode 100644
index 0000000000..4bd964199d
--- /dev/null
+++ b/test/storage/sync_file_source.test.cpp
@@ -0,0 +1,50 @@
+#include <mbgl/util/run_loop.hpp>
+#include <mbgl/util/io.hpp>
+#include <mbgl/storage/file_source.hpp>
+#include <mbgl/gfx/headless_frontend.hpp>
+#include <mbgl/map/map.hpp>
+#include <mbgl/map/map_impl.hpp>
+#include <mbgl/style/style.hpp>
+#include <mbgl/test/map_adapter.hpp>
+#include <unordered_map>
+
+#include <gtest/gtest.h>
+
+using namespace mbgl;
+
+class SyncFileSource : public FileSource {
+public:
+    std::unique_ptr<AsyncRequest> request(const Resource& resource, FileSource::Callback callback) {
+        Response response;
+        auto it = assets.find(resource.url);
+        if (it == assets.end()) {
+            response.error = std::make_unique<Response::Error>(
+                Response::Error::Reason::NotFound, std::string{ "Not Found: " } + resource.url);
+        } else {
+            response.data = it->second;
+        }
+        callback(response);
+        return nullptr;
+    }
+
+    void add(std::string const& key, std::string const& data) {
+        assets.emplace(key, std::make_shared<std::string>(data));
+    };
+
+private:
+    std::unordered_map<std::string, std::shared_ptr<std::string>> assets;
+};
+
+TEST(SyncFileSource, LoadSyncRender) {
+    util::RunLoop loop;
+    auto fs = std::make_shared<SyncFileSource>();
+    fs->add("mapbox://mapbox.mapbox-terrain-v2,mapbox.mapbox-streets-v7",
+            util::read_file("test/fixtures/resources/source_vector.json"));
+    fs->add("mapbox://sprites/mapbox/streets-v9.png",
+            util::read_file("test/fixtures/resources/sprite.png"));
+    fs->add("mapbox://sprites/mapbox/streets-v9.json",
+            util::read_file("test/fixtures/resources/sprite.json"));
+    HeadlessFrontend frontend{ { 512, 512 }, 1.0 };
+    MapAdapter map{ frontend, MapObserver::nullObserver(), fs, MapOptions() };
+    map.getStyle().loadJSON(util::read_file("test/fixtures/resources/style_vector.json"));
+}
diff --git a/test/test-files.json b/test/test-files.json
index e46f833269..f5e4013029 100644
--- a/test/test-files.json
+++ b/test/test-files.json
@@ -46,6 +46,7 @@
         "test/storage/online_file_source.test.cpp",
         "test/storage/resource.test.cpp",
         "test/storage/sqlite.test.cpp",
+        "test/storage/sync_file_source.test.cpp",
         "test/style/conversion/conversion_impl.test.cpp",
         "test/style/conversion/function.test.cpp",
         "test/style/conversion/geojson_options.test.cpp",