Passing values from Discovery to Run when generating tests

passing-values-from-discovery.tests.ps1

# original gist by Jakub

Describe "a" {
    $Sources = @(
        [PSCustomObject]@{
            Advanced = @{
                Enabled = $true
            }
        }
        [PSCustomObject]@{
            Advanced = @{
                Enabled = $true
            }
        }
    )
    foreach ($Source in $Sources) {
        It "not happy" -Skip {
            # $Source is null, because variables are not transferred
            # from discovery - this test fails
            $Source.Advanced | Should -BeTrue
        }

        It "happy" -TestCases @{ Source = $Source } {
            # $Source is defined from the test case above where
            # you saved it during discovery - this test passes
            $Source.Advanced | Should -BeTrue
        }
    }

    # same as above with inline foreach

    It "more happy" -TestCases ($Sources | % {@{ Source = $_ }}) {
        $Source.Advanced | Should -BeIn @($true, $false)
    }

    $Sources2 = @(
        [HashTable]@{
            Advanced = @{
                Enabled = $true
            }
        }
        [HashTable]@{
            Advanced = @{
                Enabled = $false
            }
        }
    )

    It "more happy 2" -TestCases $Sources2 {
        $Advanced | Should -BeIn @($true, $false)
    }

    # convert original (any) object to dictionary array
    # this loses the reference to the original object, which might or might not be a problem
    It "more happy 3" -TestCases ($Sources | ConvertTo-Json | ConvertFrom-Json -AsHashtable) {
        $Advanced | Should -BeIn @($true, $false)
    }


    # or you can declare that as filter and reuse it in the code
    filter AsHash {$_ | ConvertTo-Json | ConvertFrom-Json -AsHashtable}

    It "more happy 4" -TestCases ($Sources | AsHash) {
        $Advanced | Should -BeIn @($true, $false)
    }

}

• recommended way, without foreach <- this sounds as this is the recommended way to do this above the first approach, I would phrase it as "same as above with inline foreach"
• [Collections.IDictionary] <- this is not really needed, hashtable is okay.
• ($Sources | ConvertTo-Json | ConvertFrom-Json -AsHashtable) <- this loses the reference to the original object, which might or might not be a problem.

I will update it :)

Updated and added also filter example at the end