[CHORE]: move utf8 functions from daft-dsl to daft-functions

[ConeyLiu]

This refers to #2854 moving the UTF-8 functions from daft-dsl to daft-functions

[ConeyLiu]

Three macros are ugly, I haven't been able to find better solutions. I would appreciate any assistance or suggestions.

[universalmind303]

I think if we created a few helper functions:

fn utf8_unary(
    func: impl Fn(ExprRef) -> ExprRef,
    sql_name: &str,
    arg_name: &str,
    inputs: &[sqlparser::ast::FunctionArg],
    planner: &crate::planner::SQLPlanner,
) -> SQLPlannerResult<ExprRef> {
    match inputs {
        [input] => {
            let input = planner.plan_function_arg(input)?;
            Ok(func(input))
        }
        _ => invalid_operation_err!(
            "invalid arguments for {sql_name}. Expected {sql_name}({arg_name})",
        ),
    }
}

fn utf8_binary(...) 
fn utf3_ternary(...)

that'd allow us to simplify the macros into a single one pretty easily. It also pulls the bulk of the code out of macro which will cut down on code generation during compiling.

with the helper functions, you can create a single macro that matches on all 3 patterns

macro_rules! utf8_function {
    ($name:ident, $sql_name:expr, $func:expr, $doc:expr, $arg_name:expr) => {
        // ...
        impl SQLFunction for $name {
            fn to_expr(..) -> SQLPlannerResult<ExprRef> {
                utf8_unary($func, $sql_name, $arg_name, inputs, planner)
            }
            // ...
        }
    };
    ($name:ident, $sql_name:expr, $func:expr, $doc:expr, $arg_name_1:expr, $arg_name_2:expr) => {
        // ...
        impl SQLFunction for $name {
            fn to_expr(..) -> SQLPlannerResult<ExprRef> {
                utf8_binary($func, $sql_name, $arg_name_1, $arg_name_2, inputs, planner)
            }
            // ...
        }
    };
    ($name:ident, $sql_name:expr, $func:expr, $doc:expr, $arg_name_1:expr, $arg_name_2:expr, $arg_name_3:expr) => {
        // ...
        impl SQLFunction for $name {
            fn to_expr(..) -> SQLPlannerResult<ExprRef> {
                utf8_ternary($func, $sql_name, $arg_name_1, $arg_name_2, $arg_name_3, inputs, planner)
            }
            // ...
        }
    };
}

[ConeyLiu]

Cool, I have updated it based on your suggestions.

[codspeed-hq]

CodSpeed Performance Report

Merging #3101 will degrade performances by 21.32%

_{Comparing ConeyLiu:move-utf8 (030483f) with main (5c00dbc)}

Summary

❌ 1 regressions
✅ 16 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	ConeyLiu:move-utf8	Change
❌	test_show[100 Small Files]	40 ms	50.9 ms	-21.32%

[ConeyLiu]

@universalmind303 I think this should be a bug. The regexp_replace set the regexp to True, while the implementation is not.

[ConeyLiu]

@universalmind303 could you help to review this again? Thanks a lot.

[universalmind303]

@universalmind303 could you help to review this again? Thanks a lot.

sorry for the delay. Ill take a look at it today!

[universalmind303]

@ConeyLiu Looks good! Thanks for this! Once the conflicts are resolved, I can go ahead and merge this in!

[ConeyLiu]

Thanks @universalmind303 for your time. I have rebased it.

[ConeyLiu]

A small fix since this breaks the doc tests.