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powershell/PSAvoidNullOrEmptyHelpMessageAttribute is a PSScriptAnalyzer diagnostic emitted by tally for PowerShell snippets embedded in Dockerfiles.
PropertyValue
SeverityWarning
CategoryPSScriptAnalyzer
Auto-fixNo

​
Description

The value of the HelpMessage attribute should not be an empty string or a null value as this causes PowerShell’s interpreter to throw an error when executing the function or cmdlet.

​
How

Specify a value for the HelpMessage attribute.

​
Examples

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Problematic code

Function BadFuncEmptyHelpMessageEmpty
{
    Param(
        [Parameter(HelpMessage='')]
        [String]
        $Param
    )

    $Param
}

Function BadFuncEmptyHelpMessageNull
{
    Param(
        [Parameter(HelpMessage=$null)]
        [String]
        $Param
    )

    $Param
}

Function BadFuncEmptyHelpMessageNoAssignment
{
    Param(
        [Parameter(HelpMessage)]
        [String]
        $Param
    )

    $Param
}

​
Correct code

Function GoodFuncHelpMessage
{
    Param(
        [Parameter(HelpMessage='This is helpful')]
        [String]
        $Param
    )

    $Param
}

​
Source

This rule documentation is adapted from Microsoft’s PSScriptAnalyzer documentation for AvoidNullOrEmptyHelpMessageAttribute, licensed under CC BY 4.0.