fn parse_match_arg_attrs(attrs: &[Attribute]) -> Result<MatchArgAttrs>Expand description
Parse #[match_arg(...)] attributes from a list of syn::Attribute.
Extracts rename, rename_all, alias and listed keys. Validates that
rename_all uses one of the supported modes: snake_case, kebab-case,
lower, upper. Returns Err for unknown attribute keys or unsupported
rename_all values. listed = <bool> applies to every alias of the same
#[match_arg(...)] (#2148), so it needs one there, once, with a bool
value. Where alias may appear (variants only) is the caller’s check.