diff --git a/lib/src/node/value/calculation.dart b/lib/src/node/value/calculation.dart
index ae3a8bd88..b51122348 100644
--- a/lib/src/node/value/calculation.dart
+++ b/lib/src/node/value/calculation.dart
@@ -93,7 +93,7 @@ final JSClass calculationOperationClass = () {
     _assertCalculationValue(left);
     _assertCalculationValue(right);
     return SassCalculation.operateInternal(operator, left, right,
-        inMinMax: false, simplify: false);
+        inLegacySassFunction: false, simplify: false);
   });
 
   jsClass.defineMethods({
@@ -109,7 +109,7 @@ final JSClass calculationOperationClass = () {
 
   getJSClass(SassCalculation.operateInternal(
           CalculationOperator.plus, SassNumber(1), SassNumber(1),
-          inMinMax: false, simplify: false))
+          inLegacySassFunction: false, simplify: false))
       .injectSuperclass(jsClass);
   return jsClass;
 }();
diff --git a/lib/src/value/calculation.dart b/lib/src/value/calculation.dart
index a5b749453..4dfd18fcc 100644
--- a/lib/src/value/calculation.dart
+++ b/lib/src/value/calculation.dart
@@ -506,10 +506,25 @@ class SassCalculation extends Value {
       case (SassNumber number, null, null):
         return _matchUnits(number.value.round().toDouble(), number);
 
+      case (SassNumber number, SassNumber step, null)
+          when (!number.hasCompatibleUnits(step)):
+        _verifyCompatibleNumbers([number, step]);
+        return SassCalculation._("round", [number, step]);
+
       case (SassNumber number, SassNumber step, null):
         _verifyCompatibleNumbers([number, step]);
         return _roundWithStep('nearest', number, step);
 
+      case (
+            SassString(text: 'nearest' || 'up' || 'down' || 'to-zero') &&
+                var strategy,
+            SassNumber number,
+            SassNumber step
+          )
+          when (!number.hasCompatibleUnits(step)):
+        _verifyCompatibleNumbers([number, step]);
+        return SassCalculation._("round", [strategy, number, step]);
+
       case (
           SassString(text: 'nearest' || 'up' || 'down' || 'to-zero') &&
               var strategy,