in src/printers.ts [136:150]
function printEnum(type: GraphQLEnumType): string {
const values = type
.getValues()
.map(
(value, i) =>
printDescription(value, ' ', !i) +
' ' +
value.name +
printDirectiveField(value),
);
return (
printDescription(type) + `enum ${type.name}` + printBlock(type, values)
);
}