Private parameters are reported as unused

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• Make sure you are able to repro it on the latest released version
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Steps to reproduce

Run the analyzer against this script.

Param (
    [String] $private:var1
)

function Test-Second
{
    # $var1 is not accessible because it was private to the script.
    Write-Information -InformationAction "continue" "From script: $var1"

    # $var2 is not private to the calling function so we can access it.
    Write-Information -InformationAction "continue" "From caller: $var2"
}

function Test-NotGlobal
{
    Param (
        [String] $var2
    )
    $a = $var1 + " " + $var2
    Write-Information -InformationAction "continue" "Concatenation: $a"
    Test-Second
}

Test-NotGlobal $var1

Expected behavior

Expect no errors because $private:var1 and the use in the last line of $var1 are the same variable and $var1 is private to the script, as required.

Actual behavior

PS C:\Users\pauldsmith> Invoke-ScriptAnalyzer c:\temp\gvar.ps1

RuleName                            Severity     ScriptName Line  Message
--------                            --------     ---------- ----  -------
PSReviewUnusedParameter             Warning      gvar.ps1   2     The parameter 'private:var1' has been declared but not
                                                                  used.


PS C:\Users\pauldsmith>

If an unexpected error was thrown then please report the full error details using e.g. $error[0] | Select-Object *

Environment data

> $PSVersionTable

Name                           Value
----                           -----
PSVersion                      5.1.22621.963
PSEdition                      Desktop
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}
BuildVersion                   10.0.22621.963
CLRVersion                     4.0.30319.42000
WSManStackVersion              3.0
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1

> (Get-Module -ListAvailable PSScriptAnalyzer).Version | ForEach-Object { $_.ToString() }

1.21.0

まず、PowerShell の再現コードに対して Invoke-ScriptAnalyzer を実行し、PSReviewUnusedParameter ルールの実装とカバレッジを調べます。private パラメーターとその最後の使用箇所が同じ変数として認識されることを確認します。完了の条件は、再現コードで未使用パラメーターの警告が生成されないことです。