Mocking wiht Pester-CodePudding

I am an utter newbie regarding PowerShell and Pester. I followed some trainings about Pester and how to create tests but I am not very clear about it. I have a small function that checks the Hash of an online PDF and I have written a test for it but I am not sure if I am doing it the right way. I would appreciate any help/explanation.

Function to Test:

function Get-FileHashFromUrl {
    try {
        $wc = [System.Net.WebClient]::new()
        Get-FileHash -InputStream($wc.OpenRead("https://example.com/apps/info.pdf"))
    }
    catch {
        return $Error
    }
}

Test with Perster 5.3

BeforeAll {
    . $PSScriptRoot\myScript.ps1
}
Describe "Get-FileHashFromUrl" {
    It 'Get the PDF Hash from Url' {
        Mock -CommandName Get-FileHashFromUrl -MockWith { $hash }
        $hash = '7EE8DB731BF3E5F7CF4C8688930D1EB079738A3372EE18C118F9F4BA22064411'
        Get-FileHashFromUrl | Should -Be $hash
        Assert-MockCalled Get-FileHashFromUrl -Times 1 -Exactly
    }
}

CodePudding user response：

I'm not sure I'd be using the

You'd either want to change your function to return just the hash, like so:

function Get-FileHashFromUrl {
    try {
        $wc = [System.Net.WebClient]::new()
        return (Get-FileHash -InputStream($wc.OpenRead("https://example.com/apps/info.pdf"))).Hash
    }
    catch {
        return $Error
    }
}

Or, change your test to:

BeforeAll {
    . $PSScriptRoot\myScript.ps1
}
Describe "Get-FileHashFromUrl" {
    It 'Get the PDF Hash from Url' {
        $hash = '7EE8DB731BF3E5F7CF4C8688930D1EB079738A3372EE18C118F9F4BA22064411'
        (Get-FileHashFromUrl).Hash | Should -Be $hash
    }
}