Powershell 单元测试用例

Question

我在powershell中有一个命令，我两次调用相同的命令，我期待第一次它会返回一个值，第二次它会抛出一个错误，知道如何测试这段代码吗？
如何为我的模拟命令提供多种实现？

try{
      Write-output "hello world"
}Catch{
throw "failed to print"
}

try {
     write-output "hello world"
}Catch{
throw "failed to print hello world"
} 

Answer 1

您可以向 Mock 添加一些逻辑，以便它检查它之前是否已执行过，然后结果会有所不同。

下面的 Pester 检查脚本是否抛出了我们预期的确切错误消息，并检查 Write-Output被调用了两次:

Function YourCode {

    try{
          Write-output "hello world"
    }
    catch{
        throw "failed to print"
    }

    try {
         write-output "hello world"
    }
    catch{
        throw "failed to print hello world"
    }
} 


Describe 'YourCode Tests' {

    $Script:MockExecuted = $false

    Mock Write-Output {

        if ($Script:MockExecuted) {
            Throw
        }
        else {
            $Script:MockExecuted = $true
        }
    }

    It 'Should throw "failed to print hello world"' {
        { YourCode } | Should -Throw 'failed to print hello world'
    }

    It 'Should have called write-output 2 times' {
        Assert-MockCalled Write-Output -Times 2 -Exactly
    }
}

请注意，我将您的代码包装在一个函数中，以便可以在脚本 block 中调用它来检查 Throw , 但这可以通过点源脚本轻松完成