Implement MISRA-C++23 Preprocesser package rules 19-0-4, 19-1-1, and 19-2-1

[MichaelRFairhurst]

Description

Also includes two files in cpp/util which I intend to port to qtil package (CondensedList and Pair).

Change request type

• Release or process automation (GitHub workflows, internal scripts)
• Internal documentation
• External documentation
• Query files (.ql, .qll, .qls or unit tests)
• External scripts (analysis report or other code shipped as part of a release)

Rules with added or modified queries

• No rules added
• Queries have been added for the following rules:
  • RULE-19-0-4, RULE-19-1-1, RULE-19-2-1
• Queries have been modified for the following rules:
  • rule number here

Release change checklist

A change note (development_handbook.md#change-notes) is required for any pull request which modifies:

• The structure or layout of the release artifacts.
• The evaluation performance (memory, execution time) of an existing query.
• The results of an existing query in any circumstance.

If you are only adding new rule queries, a change note is not required.

Author: Is a change note required?

• Yes
• No

🚨🚨🚨
Reviewer: Confirm that format of shared queries (not the .qll file, the
.ql file that imports it) is valid by running them within VS Code.

• Confirmed

Reviewer: Confirm that either a change note is not required or the change note is required and has been added.

• Confirmed

Query development review checklist

For PRs that add new queries or modify existing queries, the following checklist should be completed by both the author and reviewer:

Author

• Have all the relevant rule package description files been checked in?
• Have you verified that the metadata properties of each new query is set appropriately?
• Do all the unit tests contain both "COMPLIANT" and "NON_COMPLIANT" cases?
• Are the alert messages properly formatted and consistent with the style guide?
• Have you run the queries on OpenPilot and verified that the performance and results are acceptable?
  As a rule of thumb, predicates specific to the query should take no more than 1 minute, and for simple queries be under 10 seconds. If this is not the case, this should be highlighted and agreed in the code review process.
• Does the query have an appropriate level of in-query comments/documentation?
• Have you considered/identified possible edge cases?
• Does the query not reinvent features in the standard library?
• Can the query be simplified further (not golfed!)

Reviewer

• Have all the relevant rule package description files been checked in?
• Have you verified that the metadata properties of each new query is set appropriately?
• Do all the unit tests contain both "COMPLIANT" and "NON_COMPLIANT" cases?
• Are the alert messages properly formatted and consistent with the style guide?
• Have you run the queries on OpenPilot and verified that the performance and results are acceptable?
  As a rule of thumb, predicates specific to the query should take no more than 1 minute, and for simple queries be under 10 seconds. If this is not the case, this should be highlighted and agreed in the code review process.
• Does the query have an appropriate level of in-query comments/documentation?
• Have you considered/identified possible edge cases?
• Does the query not reinvent features in the standard library?
• Can the query be simplified further (not golfed!)

[Copilot]

Pull Request Overview

This pull request implements new CodeQL queries to enforce MISRA-C++23 preprocessor rules (RULE-19-0-4, RULE-19-1-1, and RULE-19-2-1), and it adds test cases to verify improper include guards and misuse of the preprocessor.

• Added test files with intentionally malformed include guards and misuse of the "defined" operator.
• Created new QL query files to detect violations of MISRA preprocessor rules.
• Updated common utilities and exclusion lists to support preprocessor-related queries.

Reviewed Changes

Copilot reviewed 34 out of 34 changed files in this pull request and generated 2 comments.

File	Description
cpp/misra/test/rules/RULE-19-2-1/invalid2.h	Test file with an include guard using "#ifdef" instead of "#ifndef".
cpp/misra/test/rules/RULE-19-2-1/invalid1.h	Test file with a spelling mismatch in the include guard macros.
Other files	New queries and supporting files for enforcing MISRA preprocessor rules.

[lcartey]

Looks good - mostly suggestion on 19.2.1, where we have some prior art.

[lcartey]

In other Coding Standard queries we use the HeaderFile class to identify header files, based on the extension. The advantage of this approach is that we will report contraventions in files in header libraries that are not included within the header library itself. Given that this can be an important case, and for consistency reasons, I would suggest we switch definitions.

[lcartey]

My recollection is that these two conditions are already factored in within the the CorrectIncludeGuard. Is that not the case? Specifically startsWithIfndef has the following:

  exists(Location loc |
    loc = ifndef.getLocation() and
    loc.getFile() = hf and
    loc.getStartLine() = min(int l | includeGuardRelevantLine(hf, l))
  )

Which should enforce that the condition appears on the first meaningful line of the file?

[lcartey]

I would suggest reviewing the IncludeGuardsNotUsed shared query to see if it could be reused here. It does cover one additional case not covered by this query - the case where the identifier used in an include guard is duplicated across multiple header files.

[lcartey]

The rule permits comments anywhere - perhaps add a test where there are additional comments after the #if and #endif.

[lcartey]

Minor: I would recognise this as a sparse list or sparse array - I don't think I've seen the term condensed list before.