Add check for whitespace at end of line

[pcgeek86]

To keep PowerShell code tidy, we should check to see if the line ends with whitespace characters. If it does, then we should recommend trimming the trailing whitespace, and even fix it automatically for the developer.

This is similar to one of the requirements in the PEP8 guideline for Python, which is validated by the Pylint module.

https://www.python.org/dev/peps/pep-0008/

Cheers,
Trevor Sullivan

[bergmeister]

@pcgeek86 @twwilliams
This has been in implemented at the end of 2017 in the rule AvoidTrailingWhitespace.
This is how it looks like:

C:\Users\cberg\git> Invoke-ScriptAnalyzer -ScriptDefinition 'Get-Something '

RuleName                            Severity     ScriptName Line  Message
--------                            --------     ---------- ----  -------
PSAvoidTrailingWhitespace           Information             1     Line has trailing whitespace

However, note that this rule is not enabled by default in the PowerShell extension of VSCode. To do so, press Ctrl + Shift +P and then type PowerShell: Select PSScriptAnalyzer rules, click on it and then you get a list of checkboxes that you can check, just remember to click Confirm at the end. Also note that VsCode can fix the violation automatically (either manually or automatically when saving the file).

[pcgeek86]

@bergmeister Awesome! Thanks for the detailed pointer. Can users also set this in their VSCode settings file?

[bergmeister]

@pcgeek86 I think so, but I refer to https://github.com/PowerShell/vscode-powershell or @rkeithhill for that.

[mrichman]

I just tried finding PSAvoidTrailingWhitespace and it's not available. I'm using VSCode extension version 1.5.1.

[bergmeister]

@mrichman Maybe you missed a step. See below for an example and let me know if it worked for you.

[mrichman]

The only option with "white" in the name is as follows:

Does the underlying engine require updating, or is the Powershell extension supposed to take care of this?

[bergmeister]

@mrichman As far as I know from the guys who develop the extension: the extension (the PowerShellEditorServices to be precise, which are part of the extension) itself contains a version of PSSA as a fallback if PSSA is not installed. Maybe you have an old version of PSSA installed that the extension decides to use then?
What is the output of the following?

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

[mrichman]

@bergmeister 1.16.1

[bergmeister]

@mrichman That looks fine. If a reinstall of the extension does not solve it please raise an issue in the PowerShellEditorServices repo then please. cc @rkeithhill @tylerl0706 @SeeminglyScience

[rkeithhill]

BTW if you are already using VSCode, simply add the following user setting and VSCode will ensure you have no trailing whitespace:

    "files.trimTrailingWhitespace": true,

If you only want this setting to apply to PowerShell script then use this:

    "[powershell]": {
        "files.trimTrailingWhitespace": true
    },

[mrichman]

@rkeithhill Awesome! I didn't know you do could that on a per-language basis. Thanks!