PowerShell-PowerShell/test/powershell/Modules/Microsoft.PowerShell.Utility/Get-Unique.Tests.ps1

Describe "Get-Unique DRT Unit Tests" -Tags "CI" {
    It "Command get-unique works with AsString switch" {
        $inputArray = "aa","aa","Aa","ba","BA","BA"
        $results = $inputArray | Get-Unique -AsString

        $results.Length | Should Be 4

        $results[0] | Should Be "aa"
        $results[1] | Should Be "Aa"
        $results[2] | Should Be "ba"
        $results[3] | Should Be "BA"

        $results[0] | Should BeOfType "System.String"
        $results[1] | Should BeOfType "System.String"
        $results[2] | Should BeOfType "System.String"
        $results[3] | Should BeOfType "System.String"
    }
}

Describe "Get-Unique" -Tags "CI" {

    BeforeAll {
        $sortedList1 = 1,2,2,3,3,4,5
        $expectedOutput1 = 1,2,3,4,5
        $collection     = "a", "b", "b", "d"
        $expectedOutput2 = "a", "b", "d"
    }

    It "Should be able to use the Get-Unique cmdlet without error with inputObject switch" {
        { Get-Unique -InputObject $sortedList1 } | Should Not Throw
    }

    It "Should output an array" {
        $result = Get-Unique -InputObject $sortedList1
        $result | Should Not BeNullOrEmpty
        ,$result | Should BeOfType "System.Array"
    }

    It "Should output an array of unchanged items when the InputObject switch is used" {
        $actual   = Get-Unique -InputObject $sortedList1
        $(Compare-Object $actual $sortedList1 -SyncWindow 0).Length | Should Be 0
    }

    It "Should accept piped input" {
        { $actualOutput = $sortedList1 | Get-Unique } | Should Not Throw
    }

    It "Should have the expected output when piped input is used" {
        $actualOutput   = $sortedList1 | Get-Unique
        $(Compare-Object $actualOutput $expectedOutput1 -SyncWindow 0).Length | Should Be 0
    }

    It "Should be able to input a collection in the inputObject switch" {
        $actual = Get-Unique -InputObject $collection
        $(Compare-Object $actual $collection -SyncWindow 0).Length | Should Be 0
    }

    It "Should get the unique items when piped collection input is used" {
        $actual = $collection | Get-Unique
        $(Compare-Object $actual $expectedOutput2 -SyncWindow 0).Length | Should Be 0
    }
}