1 files changed, 17 insertions, 9 deletions
diff --git a/platform/darwin/src/NSExpression+MGLAdditions.mm b/platform/darwin/src/NSExpression+MGLAdditions.mm
index 8c82c84c7d..6a61dd9abb 100644
--- a/platform/darwin/src/NSExpression+MGLAdditions.mm
+++ b/platform/darwin/src/NSExpression+MGLAdditions.mm
@@ -58,6 +58,7 @@
     // Install method-like functions, taking the number of arguments implied by
     // the selector name.
     INSTALL_METHOD(mgl_join:);
+    INSTALL_METHOD(mgl_round:);
     INSTALL_METHOD(mgl_interpolate:withCurveType:parameters:stops:);
     INSTALL_METHOD(mgl_step:from:stops:);
     INSTALL_METHOD(mgl_coalesce:);
@@ -84,6 +85,14 @@
 }
 
 /**
+ Rounds the given number to the nearest integer. If the number is halfway
+ between two integers, this method rounds it away from zero.
+ */
+- (NSNumber *)mgl_round:(NSNumber *)number {
+    return @(round(number.doubleValue));
+}
+
+/**
  A placeholder for a method that evaluates an interpolation expression.
  */
 - (id)mgl_interpolate:(id)inputExpression withCurveType:(NSString *)curveType parameters:(NSDictionary *)params stops:(NSDictionary *)stops {
@@ -487,6 +496,10 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
             @"sqrt": @"sqrt:",
             @"log10": @"log:",
             @"ln": @"ln:",
+            @"abs": @"abs:",
+            @"round": @"mgl_round:",
+            @"floor": @"floor:",
+            @"ceil": @"ceiling:",
             @"^": @"raise:toPower:",
             @"upcase": @"uppercase:",
             @"downcase": @"lowercase:",
@@ -720,9 +733,13 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
             @"log:": @"log10",
             @"ln:": @"ln",
             @"raise:toPower:": @"^",
+            @"ceiling:": @"ceil",
+            @"abs:": @"abs",
+            @"floor:": @"floor",
             @"uppercase:": @"upcase",
             @"lowercase:": @"downcase",
             @"length:": @"length",
+            @"mgl_round:": @"round",
             // Vararg aftermarket expressions need to be declared with an explicit and implicit first argument.
             @"MGL_LET": @"let",
             @"MGL_LET:": @"let",
@@ -826,18 +843,9 @@ NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
                 return [@[@"max"] arrayByAddingObjectsFromArray:arguments];
             } else if ([function isEqualToString:@"exp:"]) {
                 return [NSExpression expressionForFunction:@"raise:toPower:" arguments:@[@(M_E), self.arguments.firstObject]].mgl_jsonExpressionObject;
-            } else if ([function isEqualToString:@"ceiling:"]) {
-                return [NSExpression expressionWithFormat:@"trunc:(%@) + TERNARY(modulus:by:(%@, 1) > 0, 1, 0)",
-                        self.arguments.firstObject, self.arguments.firstObject].mgl_jsonExpressionObject;
             } else if ([function isEqualToString:@"trunc:"]) {
                 return [NSExpression expressionWithFormat:@"%@ - modulus:by:(%@, 1)",
                         self.arguments.firstObject, self.arguments.firstObject].mgl_jsonExpressionObject;
-            } else if ([function isEqualToString:@"abs:"]) {
-                return [NSExpression expressionWithFormat:@"%@ * TERNARY(%@ > 0, 1, -1)",
-                        self.arguments.firstObject, self.arguments.firstObject].mgl_jsonExpressionObject;
-            } else if ([function isEqualToString:@"floor:"]) {
-                return [NSExpression expressionWithFormat:@"trunc:(%@) - TERNARY(modulus:by:(%@, 1) < 0, 1, 0)",
-                        self.arguments.firstObject, self.arguments.firstObject].mgl_jsonExpressionObject;
             } else if ([function isEqualToString:@"mgl_join:"]) {
                 NSArray *arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
                 return [@[@"concat"] arrayByAddingObjectsFromArray:arguments];