UseCompatibleSyntax

Severity Level: Error

Default state: Disabled

Description

This rule detects syntax elements that aren't compatible with your specified PowerShell target versions. When you run this rule from PowerShell 3 or 4, it can't detect syntax that's incompatible with those versions because those versions can't parse newer syntax constructs.

Example

Noncompliant

The following example uses PowerShell 7 syntax. If TargetVersions includes 5.1 or earlier, this rule flags these statements.

$message = $IsReady ? 'Ready' : 'Not ready'
$displayName = $name ?? 'Unknown'

Compliant

if ($IsReady) {
    $message = 'Ready'
} else {
    $message = 'Not ready'
}

if ($name -ne $null) {
    $displayName = $name
} else {
    $displayName = 'Unknown'
}

Configure rule

@{
    Rules = @{
        PSUseCompatibleSyntax = @{
            Enable = $true
            TargetVersions = @(
                '6.0',
                '5.1',
                '4.0'
            )
        }
    }
}

Parameters

Enable

This parameter controls whether ScriptAnalyzer checks the code against this rule. It accepts a boolean value. To enable this rule, set this parameter to $true. The default value is $false.

TargetVersions

This parameter specifies the PowerShell versions your code must be compatible with. It accepts an array of version strings, such as '7.0', '5.1', or '4.0'. ScriptAnalyzer flags syntax that's not supported in any version you target.