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Version: v6

Describe

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Contributions are welcome in Pester-repo.

SYNOPSIS​

Creates a logical group of tests.

SYNTAX​

Describe [-Name] <string> [[-Fixture] <scriptblock>] [-Tag <string[]>] [-Skip]
 [-AllowNullOrEmptyForEach] [-ForEach <Object>]

DESCRIPTION​

Creates a logical group of tests. All Mocks, TestDrive and TestRegistry contents defined within a Describe block are scoped to that Describe; they will no longer be present when the Describe block exits. A Describe block may contain any number of Context and It blocks.

EXAMPLES​

EXAMPLE 1​

BeforeAll {
    function Add-Numbers($a, $b) {
        return $a + $b
    }
}

Describe "Add-Numbers" {
    It "adds positive numbers" {
        $sum = Add-Numbers 2 3
        $sum | Should -Be 5
    }

    It "adds negative numbers" {
        $sum = Add-Numbers (-2) (-2)
        $sum | Should -Be (-4)
    }

    It "adds one negative number to positive number" {
        $sum = Add-Numbers (-2) 2
        $sum | Should -Be 0
    }

    It "concatenates strings if given strings" {
        $sum = Add-Numbers two three
        $sum | Should -Be "twothree"
    }
}

Using Describe to group tests logically at the root of the script/container

PARAMETERS​

-AllowNullOrEmptyForEach​

Allows empty or null values for -ForEach when Run.FailOnNullOrEmptyForEach is enabled. This might be excepted in certain scenarios like using external data.

Type: System.Management.Automation.SwitchParameter
DefaultValue: False
SupportsWildcards: false
Aliases: []
ParameterSets:
- Name: (All)
  Position: Named
  IsRequired: false
  ValueFromPipeline: false
  ValueFromPipelineByPropertyName: false
  ValueFromRemainingArguments: false
DontShow: false
AcceptedValues: []
HelpMessage: ''

-Fixture​

The actual test script. If you are following the AAA pattern (Arrange-Act-Assert), this typically holds the arrange and act sections. The Asserts will also lie in this block but are typically nested each in its own It block. Assertions are typically performed by the Should command within the It blocks.

Type: System.Management.Automation.ScriptBlock
DefaultValue: ''
SupportsWildcards: false
Aliases: []
ParameterSets:
- Name: (All)
  Position: 1
  IsRequired: false
  ValueFromPipeline: false
  ValueFromPipelineByPropertyName: false
  ValueFromRemainingArguments: false
DontShow: false
AcceptedValues: []
HelpMessage: ''

-ForEach​

Allows data driven tests to be written. Takes an array of data and generates one block for each item in the array, and makes the item available as $_ in all child blocks. When the array is an array of hashtables, it additionally defines each key in the hashtable as variable.

Type: System.Object
DefaultValue: ''
SupportsWildcards: false
Aliases: []
ParameterSets:
- Name: (All)
  Position: Named
  IsRequired: false
  ValueFromPipeline: false
  ValueFromPipelineByPropertyName: false
  ValueFromRemainingArguments: false
DontShow: false
AcceptedValues: []
HelpMessage: ''

-Name​

The name of the test group. This is often an expressive phrase describing the scenario being tested.

Type: System.String
DefaultValue: ''
SupportsWildcards: false
Aliases: []
ParameterSets:
- Name: (All)
  Position: 0
  IsRequired: true
  ValueFromPipeline: false
  ValueFromPipelineByPropertyName: false
  ValueFromRemainingArguments: false
DontShow: false
AcceptedValues: []
HelpMessage: ''

-Skip​

Use this parameter to explicitly mark the block to be skipped. This is preferable to temporarily commenting out a block, because it remains listed in the output.

Type: System.Management.Automation.SwitchParameter
DefaultValue: False
SupportsWildcards: false
Aliases: []
ParameterSets:
- Name: (All)
  Position: Named
  IsRequired: false
  ValueFromPipeline: false
  ValueFromPipelineByPropertyName: false
  ValueFromRemainingArguments: false
DontShow: false
AcceptedValues: []
HelpMessage: ''

-Tag​

Optional parameter containing an array of strings. When calling Invoke-Pester, it is possible to specify a -Tag parameter which will only execute Describe blocks containing the same Tag.

Type: System.String[]
DefaultValue: '@()'
SupportsWildcards: false
Aliases:
- Tags
ParameterSets:
- Name: (All)
  Position: Named
  IsRequired: false
  ValueFromPipeline: false
  ValueFromPipelineByPropertyName: false
  ValueFromRemainingArguments: false
DontShow: false
AcceptedValues: []
HelpMessage: ''

CommonParameters​

This cmdlet supports the common parameters: -Debug, -ErrorAction, -ErrorVariable, -InformationAction, -InformationVariable, -OutBuffer, -OutVariable, -PipelineVariable, -ProgressAction, -Verbose, -WarningAction, and -WarningVariable. For more information, see about_CommonParameters.

INPUTS​

OUTPUTS​

NOTES​

VERSION​

This page was generated using comment-based help in Pester 6.0.0.