use serde::ser::{self, Serialize, SerializeMap};
use crate::error::{Error, Result};
use crate::value::{ObjectMap, Scalar, Value};
use super::value_serializer::ValueSerializer;
pub(crate) struct MapSerializer {
pub(super) entries: ObjectMap,
pub(super) next_key: Option<Scalar>,
}
impl SerializeMap for MapSerializer {
type Ok = Value;
type Error = Error;
fn serialize_key<T: ?Sized + Serialize>(&mut self, key: &T) -> Result<()> {
let key_value = key.serialize(ValueSerializer)?;
match key_value {
Value::String(s) | Value::Integer(s) | Value::Float(s) => {
self.next_key = Some(s);
Ok(())
}
_ => Err(<Error as ser::Error>::custom(
"map keys must serialize to strings",
)),
}
}
fn serialize_value<T: ?Sized + Serialize>(&mut self, v: &T) -> Result<()> {
let key = self.next_key.take().ok_or_else(|| {
<Error as ser::Error>::custom("serialize_value called without a preceding key")
})?;
self.entries.insert(key, v.serialize(ValueSerializer)?);
Ok(())
}
fn end(self) -> Result<Value> {
Ok(Value::Object(self.entries))
}
}