toJson method
Implementation
core.Map<core.String, core.dynamic> toJson() => {
if (inventorySourceRateType != null)
'inventorySourceRateType': inventorySourceRateType!,
if (minimumSpend != null) 'minimumSpend': minimumSpend!,
if (rate != null) 'rate': rate!,
if (unitsPurchased != null) 'unitsPurchased': unitsPurchased!,
};