use serde::{Deserialize, Serialize};
#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
pub enum ExprIr {
Literal(String),
ColumnRef(String),
FunctionCall {
name: String,
args: Vec<ExprIr>,
},
BinaryOp {
left: Box<ExprIr>,
op: String,
right: Box<ExprIr>,
},
Cast {
expr: Box<ExprIr>,
target_type: String,
},
Omitted,
}
impl ExprIr {
pub fn is_volatile(&self) -> bool {
match self {
ExprIr::FunctionCall { name, args } => {
const VOLATILE: &[&str] = &[
"clock_timestamp",
"timeofday",
"random",
"setseed",
"txid_current",
"txid_current_snapshot",
"txid_snapshot_xip",
"txid_snapshot_xmax",
"txid_snapshot_xmin",
"nextval",
"currval",
"lastval",
"setval",
"gen_random_uuid",
"uuid_generate_v1",
"uuid_generate_v1mc",
"uuid_generate_v4",
];
let normalized = name.to_ascii_lowercase();
let known_volatile = VOLATILE.contains(&normalized.as_str())
|| normalized
.strip_prefix("pg_catalog.")
.is_some_and(|name| VOLATILE.contains(&name));
known_volatile || args.iter().any(ExprIr::is_volatile)
}
ExprIr::BinaryOp { left, right, .. } => left.is_volatile() || right.is_volatile(),
ExprIr::Cast { expr, .. } => expr.is_volatile(),
ExprIr::Literal(_) | ExprIr::ColumnRef(_) | ExprIr::Omitted => false,
}
}
}