Importing Scripts

Importing Scripts

So far the examples have just shown a simple calculation. In practice, you will need to import at least one other script - the Script Under Test.

Let's assume you have a Calculator.ps1 script to test:

function Add-Numbers {
	param ([int] $x, [int] $y)
	$x + $y
}

You would probably write your test cases in Calculator.Tests.ps1:

Describing "Calculator" {
	Given "two numbers" {
        It "Adds" {
            Add-Numbers 1 1 | Should Be 2
        }
    }
}

If you run this, you will likely find that Add-Numbers is undefined, (unless you ran Calculator.ps1 and put Add-Numbers in your global scope). Whoops, we forgot to import the script. To import a script, dot-source it. PSate provides a very handy $TestScriptPath variable that is the path to the current test script.

# import the script
. $TestScriptPath\Calculator.ps1

Describing "Calculator" {

	Given "two numbers" {
        It "Adds" {
            Add-Numbers 1 1 | Should Be 2
        }
    }
}

At this point, your tests will run fine from Invoke-Tests (see Running Tests with Invoke-Tests), but will fail when the tests are run directly. That's because $TestScriptPath isn't defined at the top level. Fortunately, we can easily wrap this with a TestScope block:

TestScope "Calculator.ps1" {

	# import the script
	. $TestScriptPath\Calculator.ps1

    Describing "Calculator" {

		Given "two numbers" {
	        It "Adds" {
	            Add-Numbers 1 1 | Should Be 2
	        }
	    }
	}
}

Now that we imported the script from within a PSate test block, the $TestScriptPath variable is defined for us. Note that you could have used $TestScriptPath from within the Describing block or any other block.