                 expectEqual(.noError, NSDecimalPower(&result, &actual, j, .plain))
                 let expected = Decimal(pow(Double(i), Double(j)))
                 expectEqual(expected, result, "\(result) == \(i)^\(j)")
-                expectEqual(expected, pow(actual, j))
+                if #available(macOS 10.15, iOS 13, tvOS 13, watchOS 6, *) {
+                    expectEqual(expected, pow(actual, j))
+                }
             }
         }
     }

        expectFalse(zero.isNaN)
        expectFalse(zero.isSignaling)

        let d1 = Decimal(1234567890123456789 as UInt64)
        expectEqual(d1._exponent, 0)
        expectEqual(d1._length, 4)
    }
    func test_Constants() {
        expectEqual(8, NSDecimalMaxSize)

        expectEqual(Decimal(68040), Decimal(386).advanced(by: Decimal(67654)))
        expectEqual(Decimal(1.234), abs(Decimal(1.234)))
        expectEqual(Decimal(1.234), abs(Decimal(-1.234)))
        if #available(macOS 10.15, iOS 13, tvOS 13, watchOS 6, *) {
            expectTrue(Decimal.nan.magnitude.isNaN)
        }
        var a = Decimal(1234)
        var r = a
        expectEqual(.noError, NSDecimalMultiplyByPowerOf10(&r, &a, 1, .plain))
