1 files changed, 22 insertions, 0 deletions
diff --git a/platform/darwin/src/MGLSource.mm b/platform/darwin/src/MGLSource.mm
index 4f9cfb014f..2fa580df89 100644
--- a/platform/darwin/src/MGLSource.mm
+++ b/platform/darwin/src/MGLSource.mm
@@ -2,6 +2,14 @@
 
 #include <mbgl/style/source.hpp>
 
+@interface MGLSource ()
+
+// Even though this class is abstract, MGLStyle uses it to represent some
+// special internal source types like mbgl::AnnotationSource.
+@property (nonatomic) mbgl::style::Source *rawSource;
+
+@end
+
 @implementation MGLSource
 
 - (instancetype)initWithIdentifier:(NSString *)identifier
@@ -12,6 +20,20 @@
     return self;
 }
 
+- (void)addToMapView:(MGLMapView *)mapView {
+    [NSException raise:NSInvalidArgumentException format:
+     @"The source %@ cannot be added to the style. "
+     @"Make sure the source was created as a member of a concrete subclass of MGLSource.",
+     self];
+}
+
+- (void)removeFromMapView:(MGLMapView *)mapView {
+    [NSException raise:NSInvalidArgumentException format:
+     @"The source %@ cannot be removed from the style. "
+     @"Make sure the source was created as a member of a concrete subclass of MGLSource.",
+     self];
+}
+
 - (NSString *)description {
     return [NSString stringWithFormat:@"<%@: %p; identifier = %@>",
             NSStringFromClass([self class]), (void *)self, self.identifier];