iOS异步测试

简介

在iOS做单元测试的时候，写异步方法的时候是比较恶心的，系统提供的API简直不能忍，先看一下

//1. 设置一个Expectation
XCTestExpectation *expectation = [self expectationWithDescription:@"testSomeThing"];

dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
    // 3. 异步操作在3秒后完成，完成后调用fulfill，而等待的方法则继续运行");
    [expectation fulfill];
});

//2. 等待Expectation结束，超过超时时间则测试失败
[self waitForExpectationsWithTimeout:30 handler:nil];

用法

系统提供的API太过于简陋，有时候我们不希望超时的时候就立即停止测试，而是可以获取是否超时的结果，或者提供一些重试的机制，在这里封装了几个异步方法，基于MainRunLoop，提供重试机制，通过扩展XCTestCase实现，可以通过Pod导入

pod 'XCTestCaseAsync'

具体代码见后面链接，先看看用法

1. 异步测试

//1. wait with a async block
[self waitWithAsync:^(FinishBlock  _Nonnull complete) {
    // async method
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        // set finish flag, finish async
        complete();
    });
}];

2. 超时测试

//2. timeout
BOOL success = [self waitWithTimeout:3 asyncBlock:^(FinishBlock  _Nonnull complete) {
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(15 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
        complete();
    });
}];
if (success) {
    NSLog(@"block execute success");
} else {
    NSLog(@"timeout");
}

3. 重试

//3. retry
BOOL success = [self waitWithRetryTimes:3 asyncBlock:^(CompleteBlock  _Nonnull complete) {
    dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{        
        NSLog(@"failure");
        complete(NO);
    });
}];
if (success) {
    NSLog(@"block execute success");
} else {
    NSLog(@"block execute fail after retry");
}

4. swift版本如下

// 1. async test
self.wait { (complete) in
    let delay = DispatchTime.now() + .seconds(1)
    DispatchQueue.main.asyncAfter(deadline: delay, execute: {
        complete()
    })
}

// 2. timeout test
let success = self.wait(withTimeout: 3) { (complete) in
    let delay = DispatchTime.now() + .seconds(5)
    DispatchQueue.main.asyncAfter(deadline: delay, execute: {
        complete()
    })
}

// 3. retry test
let success = self.wait(withRetryTimes: 3) { (complete) in
    let delay = DispatchTime.now() + .seconds(1)
    DispatchQueue.main.asyncAfter(deadline: delay, execute: {    
        print("failure")
        complete(false);
    })
}

代码

详细代码见这里