Function rustc_resolve::diagnostics::show_candidates

pub(crate) fn show_candidates(
    err: &mut DiagnosticBuilder<'_>, 
    use_placement_span: Option<Span>, 
    candidates: &[ImportSuggestion], 
    instead: bool, 
    found_use: bool
)

When an entity with a given name is not available in scope, we search for entities with that name in all crates. This method allows outputting the results of this search in a programmer-friendly way