我正在尝试编写XCTest来验证与枚举中关联值的比较。
示例:
enum MatchType : Equatable {
case perfectMatch(Int, Int)
case lowerMatch(Int, Int)
case higherMatch(Int, Int)
}
extension MatchType {
static func == (lhs: MatchType, rhs: MatchType) -> Bool {
switch (lhs, rhs) {
case (.perfectMatch, .perfectMatch):
return true
case (.lowerMatch, .lowerMatch):
return true
case (.higherMatch, .higherMatch):
return true
default:
return false
}
}
}
我如何进行比较以确保正确的枚举而不具体了解Int是什么?
在测试中,我会执行以下操作:
func testPerfectMatch() {
let orders = [6]
let units = 6
let handler = SalesRuleHandler(orders: orders, units: units)
XCTAssertEqual(handler.matchType!, MatchType.perfectMatch(0, 0))
}
SalesRuleHandler
决定是返回枚举的完全匹配,更低匹配还是更高匹配,
class SalesRuleHandler {
private var orders: [Int]
private var units: Int
var matchType: MatchType?
init(orders: [Int], units: Int) {
self.orders = orders
self.units = units
self.matchType = self.handler()
}
private func handler() -> MatchType? {
let rule = SalesRules(orders)
if let match = rule.perfectMatch(units) {
print("Found perfect match for: \(units) in orders \(rule.orders) at index: \(match.0) which is the value \(match.1)")
return MatchType.perfectMatch(match.0, match.1)
}
else {
if let match = rule.lowerMatch(units) {
print("Found lower match for: \(units) in orders \(rule.orders) at index: \(match.0) which is the value \(match.1)")
return MatchType.lowerMatch(match.0, match.1)
}
else {
if let match = rule.higherMatch(units) {
return MatchType.higherMatch(match.0, match.1)
}
}
}
return nil
}
}
我想做的是:
如果我在orders
和units
中输入课程,则应该能够测试matchType
是perfect
,lower
还是{{1 }}。
但是,在我的测试中,我必须写类似的东西:
higher
然后将(0,0)放在索引中并返回值。
是否可以在不知道具体数字的情况下对枚举进行比较?
答案 0 :(得分:3)
您可以使用case
访问枚举的关联值。
switch (lhs, rhs) {
case (.perfectMatch(let a, let b), .perfectMatch(let c, let d):
// check equality of associated values
return a == c && b == d
// other cases...
}
您还可以使用if
语句访问类似的关联值:
if case .perfectMatch(let a, let b) = handler.matchType {
// do something with a and b
}