// SPDX-License-Identifier: Apache-2.0

// SPDX-FileCopyrightText: Copyright the Vortex contributors

use crate::expr::Expression;

use crate::expr::analysis::BooleanLabels;

use crate::expr::label_tree;

pub fn label_is_fallible(expr: &Expression) -> BooleanLabels<'_> {

label_tree(

expr,

|expr| expr.signature().is_fallible(),

|acc, &child| acc | child,

)

}

#[cfg(test)]

mod tests {

use super::*;

use crate::expr::checked_add;

use crate::expr::col;

use crate::expr::eq;

use crate::expr::is_null;

use crate::expr::lit;

use crate::expr::merge_opts;

use crate::expr::not;

use crate::scalar_fn::fns::merge::DuplicateHandling;

#[test]

fn not_is_not_fallible() {

let expr = not(col("x"));

let labels = label_is_fallible(&expr);

assert_eq!(labels.get(&expr), Some(&false));

}

#[test]

fn checked_add_defaults_to_fallible() {

let expr = checked_add(col("a"), col("b"));

let labels = label_is_fallible(&expr);

assert_eq!(labels.get(&expr), Some(&true));

}

#[test]

fn eq_not_fallible() {

let expr = eq(col("a"), lit(5));

let labels = label_is_fallible(&expr);

assert_eq!(labels.get(&expr), Some(&false));

}

#[test]

fn merge_with_error_handling_is_fallible() {

let expr = merge_opts([col("a"), col("b")], DuplicateHandling::Error);

let labels = label_is_fallible(&expr);

assert_eq!(labels.get(&expr), Some(&true));

}

#[test]

fn merge_with_rightmost_handling_is_not_fallible() {

let expr = merge_opts([col("a"), col("b")], DuplicateHandling::RightMost);

let labels = label_is_fallible(&expr);

assert_eq!(labels.get(&expr), Some(&false));

}

#[test]

fn nested_with_fallible_child() {

let child = checked_add(col("a"), col("b"));

let expr = not(child.clone());

let labels = label_is_fallible(&expr);

assert_eq!(labels.get(&child), Some(&true));

assert_eq!(labels.get(&expr), Some(&true));

}

#[test]

fn nested_without_fallible_child() {

let child = is_null(col("x"));

let expr = not(child.clone());

let labels = label_is_fallible(&expr);

assert_eq!(labels.get(&child), Some(&false));

assert_eq!(labels.get(&expr), Some(&false));

}

}