[ios, macos] Corrected polyline equality

Now that annotation classes override -isEqual:, it’s no longer appropriate to rely on -isEqual: or -containsObject: to check for the preexistence of an annotation. Those methods become deep equality tests, which have worse performance. Checking for identity allows the developer to add a polyline and polygon with identical coordinates, title, etc. to the map.

Implemented a missing -[MGLPolyline isEqual:].

Removed outdated comments about -annotationTagForAnnotation: being expensive.

1 files changed, 2 insertions, 3 deletions

diff --git a/platform/macos/src/MGLMapView.mm b/platform/macos/src/MGLMapView.mm
index 68f36e044b..e72a755f51 100644
--- a/platform/macos/src/MGLMapView.mm
+++ b/platform/macos/src/MGLMapView.mm
@@ -1820,7 +1820,7 @@ public:
     return annotationContext.annotation;
 }
 
-/// Returns the annotation tag assigned to the given annotation. Relatively expensive.
+/// Returns the annotation tag assigned to the given annotation.
 - (MGLAnnotationTag)annotationTagForAnnotation:(id <MGLAnnotation>)annotation {
     if (!annotation || _annotationTagsByAnnotation.count(annotation) == 0) {
         return MGLAnnotationTagNotFound;
@@ -1848,8 +1848,7 @@ public:
         NSAssert([annotation conformsToProtocol:@protocol(MGLAnnotation)], @"Annotation does not conform to MGLAnnotation");
 
         // adding the same annotation object twice is a no-op
-        if ([self.annotations containsObject:annotation])
-        {
+        if (_annotationTagsByAnnotation.count(annotation) != 0) {
             continue;
         }