powershell/PSShouldProcess

powershell/PSShouldProcess is a PSScriptAnalyzer diagnostic emitted by tally for PowerShell snippets embedded in Dockerfiles.

Property	Value
Severity	Warning
Category	PSScriptAnalyzer
Default	Disabled in tally
Auto-fix	No

tally disables this rule by default for Dockerfile RUN snippets because a RUN executes statements inline rather than defining cmdlets, parameters, or modules with external callers. Re-enable it with include = ["powershell/PSShouldProcess"] or by setting rules.powershell.PSShouldProcess.severity = "warning" in .tally.toml.

Description

If a cmdlet declares the SupportsShouldProcess attribute, then it should also call ShouldProcess. A violation is any function which either declares SupportsShouldProcess attribute but makes no calls to ShouldProcess or it calls ShouldProcess but does not declare SupportsShouldProcess. For more information, see the following articles:

How

To fix a violation of this rule, please call ShouldProcess method when a cmdlet declares SupportsShouldProcess attribute. Or please add SupportsShouldProcess attribute argument when calling ShouldProcess.

Examples

Problematic code

function Set-File
{
    [CmdletBinding(SupportsShouldProcess=$true)]
    Param
    (
        # Path to file
        [Parameter(Mandatory=$true)]
        $Path
    )
    'String' | Out-File -FilePath $Path
}

Correct code

function Set-File
{
    [CmdletBinding(SupportsShouldProcess=$true)]
    Param
    (
        # Path to file
        [Parameter(Mandatory=$true)]
        $Path,

        [Parameter(Mandatory=$true)]
        [string]$Content
    )

    if ($PSCmdlet.ShouldProcess($Path, ("Setting content to '{0}'" -f $Content)))
    {
        $Content | Out-File -FilePath $Path
    }
    else
    {
        # Code that should be processed if doing a WhatIf operation
        # Must NOT change anything outside of the function / script
    }
}

Source

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

​Description

​How

​Examples

​Problematic code

​Correct code

​Source

Description

How

Examples

Problematic code

Correct code

Source