Trait PerFileRule 

pub trait PerFileRule:
    Send
    + Sync
    + Debug {
    // Required methods
    fn path_scope(&self) -> &Scope;
    fn evaluate_file(
        &self,
        ctx: &Context<'_>,
        path: &Path,
        bytes: &[u8],
    ) -> Result<Vec<Violation>>;

    // Provided method
    fn max_bytes_needed(&self) -> Option<usize> { ... }
}

File-major dispatch entry-point for a per-file rule.

Rules that can evaluate one file at a time given a pre-loaded byte slice implement this trait alongside Rule and opt into the file-major path via Rule::as_per_file. The engine reads each file once per evaluation pass and calls evaluate_file on every per-file rule whose path_scope matches that file — avoiding the per-rule std::fs::read the rule-major loop would otherwise duplicate.

Implementations MUST NOT call std::fs::read themselves; the bytes argument is the engine’s already-read content. The rule’s existing Rule::evaluate implementation (which does read the file) stays in place as the rule-major fallback — it’s still the path used by alint fix (sequential filesystem mutation rules out coalesced reads there) and by fallback test harnesses.

Required Methods

fn path_scope(&self) -> &Scope

The rule’s scope. The engine checks path_scope().matches(path) before calling evaluate_file; a rule that returns Scope::match_all is in scope for every file.

fn evaluate_file( &self, ctx: &Context<'_>, path: &Path, bytes: &[u8], ) -> Result<Vec<Violation>>

Evaluate one file given the engine’s already-read byte content. The path is the relative path from the lint root; the rule should with_path(path.into()) (or clone the matched FileEntry::path if it has one in hand) on emitted violations.

Provided Methods

fn max_bytes_needed(&self) -> Option<usize>

Optional lower bound on the bytes the rule needs to evaluate. Default None means “I need the whole file.” Used as a hint; the engine in v0.9.3 reads the whole file regardless and hands it to every applicable rule — the hint is reserved for a future engine-side bounded- read optimisation.

Implementors