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Version: v5

Describe

SYNOPSIS#

Creates a logical group of tests.

SYNTAX#

Describe [-Name] <String> [-Tag <String[]>] [[-Fixture] <ScriptBlock>] [-Skip] [-ForEach <Object>] [<CommonParameters>]

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#

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"    }}

PARAMETERS#

-Name#

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

Type: StringParameter Sets: (All)Aliases:
Required: TruePosition: 1Default value: NoneAccept pipeline input: FalseAccept wildcard characters: False

-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: String[]Parameter Sets: (All)Aliases: Tags
Required: FalsePosition: NamedDefault value: @()Accept pipeline input: FalseAccept wildcard characters: False

-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: ScriptBlockParameter Sets: (All)Aliases:
Required: FalsePosition: 2Default value: NoneAccept pipeline input: FalseAccept wildcard characters: False

-Skip#

[Switch] $Focus,

Type: SwitchParameterParameter Sets: (All)Aliases:
Required: FalsePosition: NamedDefault value: FalseAccept pipeline input: FalseAccept wildcard characters: False

-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 hashatble as variable.

Type: ObjectParameter Sets: (All)Aliases:
Required: FalsePosition: NamedDefault value: NoneAccept pipeline input: FalseAccept wildcard characters: False

CommonParameters#

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

INPUTS#

OUTPUTS#

NOTES#

RELATED LINKS#

https://pester.dev/docs/commands/Describe

https://pester.dev/docs/usage/test-file-structure

https://pester.dev/docs/usage/mocking

https://pester.dev/docs/usage/testdrive

EDIT THIS PAGE#

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