Add option for ensuring specific line length

[patritzenfeld]

closes #16

• Reject if submission contains any lines with length > maxLineLength option

• Display all offending lines at once, including their location, content and total length
  

• add this as a separate syntax phase for syntaxCutoff (CodeWidth)

• Do not write any files while grading if syntaxCutoff is set to CodeWidth and disableSemantics is set.

Question: Should the config checker prevent setting syntaxCutoff to CodeWidth if maxLineLength is unset? I wasn't sure about that, since it may still be useful to directly accept any submission without considering its content (similar to not writing files if we only check the line length).

[jvoigtlaender]

To the question: No.

I also think it may be useful to configure „no other syntax checks than code width, and actually we have no restriction on code width“.

[Copilot]

Pull request overview

This PR adds an optional maxLineLength configuration to reject submissions containing overlong lines, integrates that check as a distinct syntax phase (CodeWidth) that can be selected via syntaxCutoff, and introduces an optimization to skip writing any files during grading when only the CodeWidth syntax phase is run and semantics are disabled.

Changes:

• Added maxLineLength :: Maybe Natural to the solution config and included it in config parsing/defaulting/combination.
• Introduced a new FeedbackPhase step CodeWidth and a checkLineLength phase that reports all offending lines (number, content, and length).
• Skipped file-writing in grade when syntaxCutoff == CodeWidth and disableSemantics is set.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
src/Haskell/Template/Task.hs	Adds maxLineLength, new CodeWidth phase, line-length rejection logic, and a conditional “no file writes” grading path.
.github/actions/spelling/expect.txt	Whitelists linebreak for the spelling workflow due to new pretty-print usage.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.