Allow VSCode configuration of PSScriptAnalyzer rules

[rjmholt]

To follow on from the comments starting at #1429 (comment)...

PSSA rules should be enable-able and disable-able in VSCode configuration. The current proposal is:

• Disabled rules turn off default rules, but not a local PSSA settings file
• Enabled rules add to the default rules

Current proposed format is:

{
  "powershell.scriptAnalysis.rules": {
    "disable": [
      "PSAvoidTrailingWhitespace"
    ],
    "enable": [
      "RuleThatILikeButMyColleaguesDont",
    ]
  }
}

[Halkcyon]

How would you plan on addressing rules that are configurable such as PSProvideCommentHelp or PSAvoidUsingCmdletAliases?

[rjmholt]

@TheIncorrigible1 Good question. I don't have anything particular in mind. The fact that we are even proposing to make a settings-embedded JSON configuration for a psd1-file-configured tool already feels a bit odd to me, but it seems to be what some users are asking for.

The first two solutions I can imagine suggested are:

1. You can't configure them; if you want that kind of configuration, it's time to write a psd1 file.
2. We just translate the whole psd1 schema into JSON

[fourpastmidnight]

I don't see why we can't have our cake and eat it, too! There are probably a few ways to go about this in JSON syntax, but, perhaps the easiest is to modify the proposed enable property above:

{
  "powershell.scriptAnalysis.rules": {
    "disable": [
      "PSAvoidTrailingWhitespace"
    ],
    "enable": [
      {
        "rule": "PSPlaceOpenBrace",
        "configuration": {
          "Enable": true,
          "OnSameLine": true,
          "NewLineAfter": true
        }
      },
      { "rule": "PSUseSingulareNouns" },
    ]
  }
}

So, one rule can have a configuration, while the second rule, which is not configurable, does not--so the user would not provide a configuration. But even if the user were to provide a configuration for a non-configurable rule, and even if the configuration is added to a generated PSScriptAnalyserSettings.psd1 file, wouldn't it simply be ignored since PSScriptAnalyzer would never attempt to configure it in the first place since the rule is not configurable?

[moymike]

It would be nice if PSScriptAnalyzer Rules were stored in the User Settings / Extensions area (JSON).

I ran into this as I wanted to customize which rules apply, and I chased this link down:
https://superuser.com/questions/1393186/how-to-disable-psscriptanalyzers-psavoidusingcmdletaliases-in-powershell-extens/1397066?noredirect=1#comment2107064_1397066

I set the: "powershell.scriptAnalysis.settingsPath": "", to toggle via a script (which is example #3 in the 'superuser' page.

I currently use an extension 'Settings Sync'. If the PSScriptAnalyzer Rules were stored in the User Settings, it would simplify dealing with these toggles for me, as they would sync along with all my other settings.

[mklement0]

The aspect of selective disabling / enabling of rules is essentially a duplicate of #823, which asks that the existing GUI capability of selecting rules (>PowerShell: Select PSScriptAnalyzer Rules) be persisted across sessions.

Adding rule configuration would be nice too (for which a GUI method will probably never be implemented due to complexity, if I were to guess).

@fourpastmidnight: I like the idea, but for rule-name-only entries you should be able to use just the name as a string value; e.g., "PSUseSingularNouns" rather than { "rule": "PSUseSingularNouns" }.