PowerShell/test/powershell/Measure-Object.Tests.ps1

Describe "Measure-Object" {
    $testObject = 1,3,4

    It "Should be able to be called without error" {
	{ Measure-Object | Out-Null } | Should Not Throw
    }

    It "Should be able to call on piped input" {
	{ $testObject | Measure-Object } | Should Not Throw
    }

    It "Should be able to count the number of objects input to it" {
	$($testObject | Measure-Object).Count | Should Be $testObject.Length
    }

    It "Should be able to count using the Property switch" {
	$expected = $(Get-ChildItem).Length
	$actual   = $(Get-ChildItem | Measure-Object -Property Length).Count

	$actual | Should Be $expected
    }

    It "Should be able to get additional stats" {
	$actual = Get-Process | Measure-Object -Property workingset64 -Minimum -Maximum -Average

	$actual.Average    | Should BeGreaterThan 0
	$actual.Characters | Should BeNullOrEmpty
	$actual.Lines      | Should BeNullOrEmpty
	$actual.Maximum    | Should Not BeNullOrEmpty
	$actual.Minimum    | Should Not BeNullOrEmpty
	$actual.Sum        | Should BeNullOrEmpty
    }

    Context "Numeric tests" {
	It "Should be able to sum" {
	    $actual   = $testObject | Measure-Object -Sum
	    $expected = 0

	    foreach ( $obj in $testObject )
	    {
		$expected += $obj
	    }

	    $actual.Sum | Should Be $expected
	}

	It "Should be able to average" {
	    $actual   = $testObject | Measure-Object -Average
	    $expected = 0

	    foreach ( $obj in $testObject )
	    {
		$expected += $obj
	    }

	    $expected /= $testObject.length

	    $actual.Average | Should Be $expected
	}

	It "Should be able to return a minimum" {
	    $actual   = $testObject | Measure-Object -Minimum
	    $expected = $testObject[0]

	    for ($i=0; $i -lt $testObject.length; $i++)
	    {
		if ( $testObject[$i] -lt $expected )
		{

		    $expected = $testObject[$i]
		}
	    }

	    $actual.Minimum | Should Be $expected
	}

	It "Should be able to return a minimum when multiple objects are the minimum" {
	    $testMinimum = 1,1,2,4
	    $actual      = $testMinimum | Measure-Object -Minimum
	    $expected    = $testMinimum[0]

	    for ($i=1; $i -lt $testMinimum.length; $i++)
	    {
		if ( $testMinimum[$i] -lt $expected )
		{

		    $expected = $testMinimum[$i]
		}
	    }

	    $actual.Minimum | Should Be $expected
	}

	It "Should be able to return a maximum" {
	    $actual   = $testObject | Measure-Object -Maximum
	    $expected = $testObject[0]

	    for ($i=1; $i -lt $testObject.length; $i++)
	    {
		if ( $testObject[$i] -gt $expected )
		{

		    $expected = $testObject[$i]
		}
	    }

	    $actual.Maximum | Should Be $expected
	}

	It "Should be able to return a maximum when multiple objects are the maximum" {
	    $testMaximum = 1,3,5,5
	    $actual      = $testMaximum | Measure-Object -Maximum
	    $expected    = $testMaximum[0]

	    for ($i=1; $i -lt $testMaximum.length; $i++)
	    {
		if ( $testMaximum[$i] -gt $expected )
		{

		    $expected = $testMaximum[$i]
		}
	    }

	    $actual.Maximum | Should Be $expected
	}
    }

    Context "String tests" {
	$nl = [Environment]::NewLine

	$testString = "HAD I the heavens' embroidered cloths,$nl Enwrought with golden and silver light,$nl The blue and the dim and the dark cloths$nl Of night and light and the half light,$nl I would spread the cloths under your feet:$nl But I, being poor, have only my dreams;$nl I have spread my dreams under your feet;$nl Tread softly because you tread on my dreams."

	It "Should be able to count the number of words in a string" {
	    $expectedLength = $testString.Replace($nl,"").Split().length
	    $actualLength   = $testString | Measure-Object -Word

	    $actualLength.Words | Should Be $expectedLength
	}

	It "Should be able to count the number of characters in a string" {
	    $expectedLength = $testString.length
	    $actualLength   = $testString | Measure-Object -Character

	    $actualLength.Characters | Should Be $expectedLength
	}

	It "Should be able to count the number of lines in a string" {
	    $expectedLength = $testString.Split($nl, [System.StringSplitOptions]::RemoveEmptyEntries).length
	    $actualLength   = $testString | Measure-Object -Line

	    $actualLength.Lines | Should Be $expectedLength
	}
    }
}