[core] Add more tests to on-demand source load

2 files changed, 48 insertions, 1 deletions

diff --git a/test/fixtures/resources/style-unused-sources.json b/test/fixtures/resources/style-unused-sources.json
index f87166a678..3878f85dd8 100644
--- a/test/fixtures/resources/style-unused-sources.json
+++ b/test/fixtures/resources/style-unused-sources.json
@@ -32,5 +32,17 @@
     "layout" : {
         "visibility" : "none"
     }
+  }, {
+    "id":  "classylayer",
+    "type": "symbol",
+    "source": "unusedsource",
+    "paint" : {
+        "icon-opacity" : 0,
+        "text-opacity" : 0
+    },
+    "paint.visible" : {
+        "icon-opacity" : 1,
+        "text-opacity" : 1
+    }
   }]
 }
diff --git a/test/style/unused_sources.cpp b/test/style/unused_sources.cpp
index 318a8928f7..43610ff603 100644
--- a/test/style/unused_sources.cpp
+++ b/test/style/unused_sources.cpp
@@ -68,6 +68,10 @@ public:
         callback(error, style.get());
     }
 
+    void addClass(const std::string& class_) {
+        data.addClass(class_);
+    }
+
 private:
     MapData data;
     std::unique_ptr<Style> style;
@@ -77,7 +81,7 @@ private:
     MockStyleObserverCallback callback;
 };
 
-TEST(Style, UnusedSources) {
+TEST(Style, UnusedSource) {
     util::RunLoop loop;
 
     MockView view;
@@ -108,4 +112,35 @@ TEST(Style, UnusedSources) {
     observer.reset();
 }
 
+TEST(Style, UnusedSourceActiveViaClassUpdate) {
+    util::RunLoop loop;
+
+    MockView view;
+    MockFileSource fileSource(MockFileSource::Success, "");
+
+    auto callback = [&loop](std::exception_ptr error, Style* style) {
+        loop.stop();
+
+        EXPECT_TRUE(error == nullptr);
+
+        Source *unusedSource = style->getSource("unusedsource");
+        EXPECT_TRUE(unusedSource);
+        EXPECT_TRUE(unusedSource->isLoaded());
+    };
+
+    std::unique_ptr<util::Thread<MockStyleObserver>> observer(
+        std::make_unique<util::Thread<MockStyleObserver>>(
+            util::ThreadContext{"Map", util::ThreadType::Map, util::ThreadPriority::Regular}, view, fileSource, callback));
+
+    observer->invoke(&MockStyleObserver::addClass, "visible");
+    observer->invoke(&MockStyleObserver::update);
+
+    loop.run();
+
+    // Needed because it will make the Map thread
+    // join and cease logging after this point.
+    observer->invoke(&MockStyleObserver::cleanup);
+    observer.reset();
+}
+
 } // namespace mbgl