PowerShell Introduction to Pester Getting Started with Pester
Example
To get started with unit testing PowerShell code using the Pester-module, you need to be familiar with three keywords/commands:
- Describe: Defines a group of tests. All Pester test files needs at least one Describe-block.
- It: Defines an individual test. You can have multiple It-blocks inside a Descripe-block.
- Should: The verify/test command. It is used to define the result that should be considered a successful test.
Sample:
Import-Module Pester #Sample function to run tests against function Add-Numbers{ param($a, $b) return [int]$a + [int]$b } #Group of tests Describe "Validate Add-Numbers" { #Individual test cases It "Should add 2 + 2 to equal 4" { Add-Numbers 2 2 | Should Be 4 } It "Should handle strings" { Add-Numbers "2" "2" | Should Be 4 } It "Should return an integer"{ Add-Numbers 2.3 2 | Should BeOfType Int32 } } Output:
Describing Validate Add-Numbers [+] Should add 2 + 2 to equal 4 33ms [+] Should handle strings 19ms [+] Should return an integer 23ms 
