hamelin_legacy 0.3.10

use crate::ast::expression::HamelinExpression;
use crate::ast::pipeline::HamelinPipeline;
use crate::translation::sql_query_helpers::apply_limit;
use crate::translation::PendingQuery;
use hamelin_lib::antlr::hamelinparser::{LimitCommandContext, LimitCommandContextAttrs};
use hamelin_lib::err::{TranslationError, TranslationErrors};
use hamelin_lib::types::INT;

pub fn translate(
    ctx: &LimitCommandContext<'static>,
    pipeline: &HamelinPipeline,
    previous: &PendingQuery,
) -> Result<PendingQuery, TranslationErrors> {
    let exptree = TranslationErrors::expect(ctx, ctx.expression())?;
    let exp = HamelinExpression::new(
        exptree.clone(),
        pipeline
            .context
            .default_expression_translation_context(&previous.env),
    )
    .translate()?;
    if exp.typ != INT {
        return Err(
            TranslationError::msg(exptree.as_ref(), "limit expression must be an integer").single(),
        );
    }

    Ok(PendingQuery::new(
        apply_limit(previous.query.clone(), exp.sql, &previous.env),
        previous.env.clone(),
    ))
}