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81 changes: 81 additions & 0 deletions README.md
Original file line number Diff line number Diff line change
Expand Up @@ -39,6 +39,87 @@ If you have previous version of PSScriptAnalyzer installed on your machine, you

To confirm installation: run ```Get-ScriptAnalyzerRule``` in the PowerShell console to obtain the built-in rules

Suppressing Rules
=================

You can suppress a rule by decorating a script/function or script/function parameter with .NET's [SuppressMessageAttribute](https://msdn.microsoft.com/en-us/library/system.diagnostics.codeanalysis.suppressmessageattribute.aspx). `SuppressMessageAttribute`'s constructor takes two parameters: a category and a check ID. Set the `categoryID` parameter to the name of the rule you want to suppress (you may omit the `checkID` parameter):

function SuppressMe()
{
[Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSProvideCommentHelp")]
param()

Write-Verbose -Message "I'm making a difference!"

}

All rule violations within the scope of the script/function/parameter you decorate will be suppressed.

To suppress a message on a specific parameter, set the `SuppressMessageAttribute`'s `CheckId` parameter to the name of the parameter:

function SuppressTwoVariables()
{
[Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSProvideDefaultParameterValue", "b")]
[Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSProvideDefaultParameterValue", "a")]
param([string]$a, [int]$b)
{
}
}

Use the `SuppressMessageAttribute`'s `Scope` property to limit rule suppression to functions or classes within the attribute's scope. Use the value `Function` to suppress violations on all functions within the attribute's scope. Use the value `Class` to suppress violoations on all classes within the attribute's scope:


[Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSProvideCommentHelp", "", Scope="Function")]
param(
)

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This param is not attached to any function or script. You can look at https://github.com/PowerShell/PSScriptAnalyzer/blob/master/Tests/Engine/RuleSuppression.ps1 for an example of a param block of a function, script or class. Thanks!


function InternalFunction
{
param()

Write-Verbose -Message "I am invincible!"
}

The above example demonstrates how to suppress rule violations for internal functions using the `SuppressMessageAttribute`'s `Scope` property.

You can further restrict suppression based on a function/parameter/class/variable/object's name by setting the `SuppressMessageAttribute's` `Target` property to a regular expression. Any function/parameter/class/variable/object whose name matches the regular expression is skipped.

[Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSAvoidUsingPositionalParameters", Scope="Function", Target="PositionalParametersAllowed")]
Param(
)

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This param is also not attached to a function or script or class.


function PositionalParametersAllowed()
{
Param([string]$Parameter1)
{
Write-Verbose $Parameter1
}

}

function PositionalParametersNotAllowed()
{
param([string]$Parameter1)
{
Write-Verbose $Parameter1
}
}

# The script analyzer will skip this violation
PositionalParametersAllowed 'value1'

# The script analyzer will report this violation
PositionalParametersNotAllowed 'value1

To match all functions/variables/parameters/objects, use `*` as the value of the Target parameter:

[Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSAvoidUsingPositionalParameters", Scope="Function", Target="*")]
Param(
)




Building the Code
=================

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