1 files changed, 29 insertions, 1 deletions
diff --git a/platform/darwin/src/NSCompoundPredicate+MGLAdditions.mm b/platform/darwin/src/NSCompoundPredicate+MGLAdditions.mm
index 0039b5af82..19568b8033 100644
--- a/platform/darwin/src/NSCompoundPredicate+MGLAdditions.mm
+++ b/platform/darwin/src/NSCompoundPredicate+MGLAdditions.mm
@@ -1,7 +1,7 @@
 #import "NSCompoundPredicate+MGLAdditions.h"
 
 #import "NSPredicate+MGLAdditions.h"
-#import "NSExpression+MGLAdditions.h"
+#import "NSExpression+MGLPrivateAdditions.h"
 
 @implementation NSCompoundPredicate (MGLAdditions)
 
@@ -71,3 +71,31 @@
 }
 
 @end
+
+@implementation NSCompoundPredicate (MGLExpressionAdditions)
+
+- (id)mgl_jsonExpressionObject {
+    switch (self.compoundPredicateType) {
+        case NSNotPredicateType: {
+            NSAssert(self.subpredicates.count <= 1, @"NOT predicate cannot have multiple subpredicates.");
+            NSPredicate *subpredicate = self.subpredicates.firstObject;
+            return @[@"!", subpredicate.mgl_jsonExpressionObject];
+        }
+            
+        case NSAndPredicateType: {
+            NSArray *subarrays = [self.subpredicates valueForKeyPath:@"mgl_jsonExpressionObject"];
+            return [@[@"all"] arrayByAddingObjectsFromArray:subarrays];
+        }
+            
+        case NSOrPredicateType: {
+            NSArray *subarrays = [self.subpredicates valueForKeyPath:@"mgl_jsonExpressionObject"];
+            return [@[@"any"] arrayByAddingObjectsFromArray:subarrays];
+        }
+    }
+    
+    [NSException raise:@"Compound predicate type not handled"
+                format:@""];
+    return nil;
+}
+
+@end