[ios, macos] Hardened std::map usage in MGLMapVIew

Replaced std::map::operator[] usage with std::map::at(). Backed up an assertion on iOS with a guard when -annotationTagsInRect: returns the tag of a nonexistent annotation, for consistency with macOS. Removed an unnecessary and risky subscript into _annotationContextsByAnnotationTag in -positioningRectForCalloutForAnnotationWithTag: on iOS.

1 files changed, 2 insertions, 2 deletions

diff --git a/platform/macos/src/MGLMapView.mm b/platform/macos/src/MGLMapView.mm
index fc9834e016..a5a5c53df3 100644
--- a/platform/macos/src/MGLMapView.mm
+++ b/platform/macos/src/MGLMapView.mm
@@ -1820,7 +1820,7 @@ public:
         return nil;
     }
 
-    MGLAnnotationContext &annotationContext = _annotationContextsByAnnotationTag[tag];
+    MGLAnnotationContext &annotationContext = _annotationContextsByAnnotationTag.at(tag);
     return annotationContext.annotation;
 }
 
@@ -2057,8 +2057,8 @@ public:
         // Filter out any annotation whose image is unselectable or for which
         // hit testing fails.
         auto end = std::remove_if(nearbyAnnotations.begin(), nearbyAnnotations.end(), [&](const MGLAnnotationTag annotationTag) {
-            NSAssert(_annotationContextsByAnnotationTag.count(annotationTag) != 0, @"Unknown annotation found nearby click");
             id <MGLAnnotation> annotation = [self annotationWithTag:annotationTag];
+            NSAssert(annotation, @"Unknown annotation found nearby click");
             if (!annotation) {
                 return true;
             }