Function clippy_lints::utils::comparisons::normalize_comparison

pub fn normalize_comparison<'a>(op: BinOp_,
                                lhs: &'a Expr,
                                rhs: &'a Expr)
                                -> Option<(Rel, &'a Expr, &'a Expr)>

Put the expression in the form lhs < rhs, lhs <= rhs, lhs == rhs or lhs != rhs.