Function rewrite_expr

datafusion/expr/src/expr_rewriter/guarantees.rs:100–128

(
    expr: Expr,
    guarantees: &HashMap<&Expr, &NullableInterval>,
)

}

fn rewrite_expr(
    expr: Expr,
    guarantees: &HashMap<&Expr, &NullableInterval>,
) -> Result<Transformed<Expr>> {
    // If an expression collapses to a single value, replace it with a literal
    if let Some(interval) = guarantees.get(&expr)
        && let Some(value) = interval.single_value()
    {
        return Ok(Transformed::yes(lit(value)));
    }

    let result = match expr {
        Expr::IsNull(inner) => match guarantees.get(inner.as_ref()) {
            Some(NullableInterval::Null { .. }) => Transformed::yes(lit(true)),
            Some(NullableInterval::NotNull { .. }) => Transformed::yes(lit(false)),
            _ => Transformed::no(Expr::IsNull(inner)),
        },
        Expr::IsNotNull(inner) => match guarantees.get(inner.as_ref()) {
            Some(NullableInterval::Null { .. }) => Transformed::yes(lit(false)),
            Some(NullableInterval::NotNull { .. }) => Transformed::yes(lit(true)),
            _ => Transformed::no(Expr::IsNotNull(inner)),
        },
        Expr::Between(b) => rewrite_between(b, guarantees)?,
        Expr::BinaryExpr(b) => rewrite_binary_expr(b, guarantees)?,
        Expr::InList(i) => rewrite_inlist(i, guarantees)?,
        expr => Transformed::no(expr),
    };
    Ok(result)
}

fn rewrite_between(
    between: Between,