surrealpatch/lib/src/sql/param.rs
2023-06-19 19:41:13 +01:00

118 lines
2.7 KiB
Rust

use crate::ctx::Context;
use crate::dbs::Options;
use crate::err::Error;
use crate::sql::error::IResult;
use crate::sql::ident::{ident, Ident};
use crate::sql::value::Value;
use nom::character::complete::char;
use serde::{Deserialize, Serialize};
use std::fmt;
use std::ops::Deref;
use std::str;
pub(crate) const TOKEN: &str = "$surrealdb::private::sql::Param";
#[derive(Clone, Debug, Default, Eq, PartialEq, PartialOrd, Serialize, Deserialize, Hash)]
#[serde(rename = "$surrealdb::private::sql::Param")]
pub struct Param(pub Ident);
impl From<Ident> for Param {
fn from(v: Ident) -> Self {
Self(v)
}
}
impl From<String> for Param {
fn from(v: String) -> Self {
Self(v.into())
}
}
impl From<&str> for Param {
fn from(v: &str) -> Self {
Self(v.into())
}
}
impl Deref for Param {
type Target = Ident;
fn deref(&self) -> &Self::Target {
&self.0
}
}
impl Param {
/// Process this type returning a computed simple Value
pub(crate) async fn compute(&self, ctx: &Context<'_>, opt: &Options) -> Result<Value, Error> {
// Find the variable by name
match self.as_str() {
// This is a special param
"this" | "self" => match ctx.doc() {
// The base document exists
Some(v) => v.compute(ctx, opt).await,
// The base document does not exist
None => Ok(Value::None),
},
// This is a normal param
v => match ctx.value(v) {
// The param has been set locally
Some(v) => v.compute(ctx, opt).await,
// The param has not been set locally
None => {
// Clone transaction
let txn = ctx.clone_transaction()?;
// Claim transaction
let mut run = txn.lock().await;
// Get the param definition
let val = run.get_pa(opt.ns(), opt.db(), v).await;
// Check if the param has been set globally
match val {
// The param has been set globally
Ok(v) => Ok(v.value),
// The param has not been set globally
Err(_) => Ok(Value::None),
}
}
},
}
}
}
impl fmt::Display for Param {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "${}", &self.0)
}
}
pub fn param(i: &str) -> IResult<&str, Param> {
let (i, _) = char('$')(i)?;
let (i, v) = ident(i)?;
Ok((i, Param::from(v)))
}
#[cfg(test)]
mod tests {
use super::*;
use crate::sql::test::Parse;
#[test]
fn param_normal() {
let sql = "$test";
let res = param(sql);
assert!(res.is_ok());
let out = res.unwrap().1;
assert_eq!("$test", format!("{}", out));
assert_eq!(out, Param::parse("$test"));
}
#[test]
fn param_longer() {
let sql = "$test_and_deliver";
let res = param(sql);
assert!(res.is_ok());
let out = res.unwrap().1;
assert_eq!("$test_and_deliver", format!("{}", out));
assert_eq!(out, Param::parse("$test_and_deliver"));
}
}