// Copyright Materialize, Inc. and contributors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License in the LICENSE file at the
// root of this repository, or online at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! Serde utilities.

/// Used to serialize fields of Maps whose key type is not a native string. Annotate the field with
/// `#[serde(serialize_with = mz_ore::serde::map_key_to_string)]`.
pub fn map_key_to_string<'a, I, K, V, S>(map: I, serializer: S) -> Result<S::Ok, S::Error>
where
    I: IntoIterator<Item = (&'a K, &'a V)>,
    K: std::fmt::Display + 'a,
    V: serde::Serialize + 'a,
    S: serde::Serializer,
{
    use serde::ser::SerializeMap;

    let mut s = serializer.serialize_map(None)?;
    for (key, value) in map {
        s.serialize_entry(&key.to_string(), value)?;
    }
    s.end()
}