[ios, macos] Raise exception if MGLMapSnapshotter is used from thread without active run loop.

2018-05-02 11:55:58 -04:00
parent af4efd4fa7
commit df4d8bab31
1 changed files with 5 additions and 0 deletions
--- a/platform/darwin/src/MGLMapSnapshotter.mm
+++ b/platform/darwin/src/MGLMapSnapshotter.mm
@@ -108,6 +108,11 @@ const CGFloat MGLSnapshotterMinimumPixelSize = 64;

 - (void)startWithQueue:(dispatch_queue_t)queue completionHandler:(MGLMapSnapshotCompletionHandler)completion
 {
+    if (!mbgl::Scheduler::GetCurrent()) {
+        [NSException raise:NSInvalidArgumentException
+                    format:@"startWithQueue:completionHandler: must be called from a thread with an active run loop."];
+    }
+
    if ([self isLoading]) {
        [NSException raise:NSInternalInconsistencyException
                    format:@"Already started this snapshotter."];