Add new InvalidMultiDotValue rule

[iRon7]

PR Summary

Issue: #1698

PowerShell does not support an implicit value with multiple dots.
Any unquoted value with 2 or more dots will not be treated as any special type (like a version or IPAddress)
but result in $null. These objects need to be constructed from either a quoted string (e.g. [Version]'1.2.3')
or their individual components (e.g. [Version]::new(1, 2, 3)).

This rule returns an Error for unquoted values that have 2 or more dots (e.g.: $version = [Version]1.2.3).
And implements a -Fix to surround the concerned violation with single quotes.

PR Checklist

• PR has a meaningful title
  • Use the present tense and imperative mood when describing your changes
• Summarized changes
• Change is not breaking
• Make sure all .cs, .ps1 and .psm1 files have the correct copyright header
• Make sure you've added a new test if existing tests do not effectively test the code changed and/or updated documentation
• This PR is ready to merge and is not Work in Progress.
  • If the PR is work in progress, please add the prefix WIP: to the beginning of the title and remove the prefix when the PR is ready.

[liamjpeters]

👋

Looks useful, thanks!

The naming of this rule is a little awkward. It's listed as InvalidVersionConstruction in the markdown doc, so I guess you renamed it at some point? Naming things is hard! Perhaps something like InvalidDottedValue or InvalidDottedLiteral as a suggestion? I don't know though 🤷 - I'm bad at naming things - I just know the current name looks off.

This rule has a severity of Warning but is emitting a diagnostic of Error severity. Where this is the only diagnostic that your rule emits, these should match. Not sure which is more appropriate here - I can't think of a case where you'd want the unquoted dotted literal intentionally so maybe Error is correct?

In your tests, you have 2 Context blocks with the same Supressed name.

You are using the temp folder in some of your testing; I'd suggest looking into and using Pester's Test Drive for temporary file usage during tests. It helpfully takes care of relevant cleanup for you too at the right time.

I don't think the CompilerServices import is intended?

This has the same copy-pasta as your other PRs.

[iRon7]

I am trying to be precise but it is amazing how many issues you still find in PRs.
It is the end of the day for me, but I will pick them up tomorrow and respond/act accordingly.
Again, thanks for your feedback!

[iRon7]

@liamjpeters,

It's listed as InvalidVersionConstruction in the markdown doc

Fixed, although I have kept the questionable name InvalidMultiDotValue name (as I would like to avoid that I forget to update a reference again) until somebody comes up with a accurate name that better covers the scope.

This rule has a severity of Warning but is emitting a diagnostic of Error severity

Fixed

you have 2 Context blocks with the same Suppressed name.

Fixed

I don't think the CompilerServices import is intended?

Removed

This has the same copy-pasta as #2178.

Changed accordingly

[Copilot]

Pull request overview

Adds a new built-in PSScriptAnalyzer rule to detect unquoted literals containing multiple dots (which PowerShell can parse as member-access on a double and end up evaluating to $null), along with documentation and test coverage.

Changes:

• Introduces the InvalidMultiDotValue rule implementation with a -Fix suggestion to quote the multi-dot value.
• Adds localized rule strings and new rule documentation.
• Adds Pester tests covering violations, compliant cases, suppressions, and fix behavior.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
docs/Rules/README.md	Registers the new rule in the rules index table.
docs/Rules/InvalidMultiDotValue.md	New rule documentation with examples.
Tests/Rules/InvalidMultiDotValue.tests.ps1	New test suite for detection, suppression, and -Fix.
Rules/Strings.resx	Adds name/description/error/correction strings for the rule.
Rules/InvalidMultiDotValue.cs	Implements AST-based detection and suggested correction extents.

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