// Copyright 2024 The Jujutsu Authors//// 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 at//// https://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.#![allow(missing_docs)]use std::any::Any;use std::any::TypeId;use std::collections::HashMap;/// Type-safe map that stores objects of arbitrary types.////// This allows extensions to store and retrieve their own types unknown to/// jj_lib safely.#[derive(Default)]pub struct ExtensionsMap { values: HashMap<TypeId, Box<dyn Any>>,}impl ExtensionsMap { /// Creates an empty ExtensionsMap. pub fn empty() -> Self { Default::default() } /// Returns the specified type if it has already been inserted. pub fn get<V: Any>(&self) -> Option<&V> { self.values .get(&TypeId::of::<V>()) .map(|v| v.downcast_ref::<V>().unwrap()) } /// Inserts a new instance of the specified type. /// /// Requires that this type has not been inserted before. pub fn insert<V: Any>(&mut self, value: V) { assert!(self .values .insert(TypeId::of::<V>(), Box::new(value)) .is_none()); }}#[cfg(test)]mod tests { use super::*; struct TestTypeA; impl TestTypeA { fn get_a(&self) -> &'static str { "a" } } struct TestTypeB; impl TestTypeB { fn get_b(&self) -> &'static str { "b" } } #[test] fn test_empty() { let extensions_map = ExtensionsMap::empty(); assert!(extensions_map.get::<TestTypeA>().is_none()); assert!(extensions_map.get::<TestTypeB>().is_none()); } #[test] fn test_retrieval() { let mut extensions_map = ExtensionsMap::empty(); extensions_map.insert(TestTypeA); extensions_map.insert(TestTypeB); assert_eq!( extensions_map .get::<TestTypeA>() .map(|a| a.get_a()) .unwrap_or(""), "a" ); assert_eq!( extensions_map .get::<TestTypeB>() .map(|b| b.get_b()) .unwrap_or(""), "b" ); }}
// Copyright 2024 The Jujutsu Authors
//
// 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 at
//
// https://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.
#![allow(missing_docs)]
use std::any::Any;
use std::any::TypeId;
use std::collections::HashMap;
/// Type-safe map that stores objects of arbitrary types.
///
/// This allows extensions to store and retrieve their own types unknown to
/// jj_lib safely.
#[derive(Default)]
pub struct ExtensionsMap {
values: HashMap<TypeId, Box<dyn Any>>,
}
impl ExtensionsMap {
/// Creates an empty ExtensionsMap.
pub fn empty() -> Self {
Default::default()
}
/// Returns the specified type if it has already been inserted.
pub fn get<V: Any>(&self) -> Option<&V> {
self.values
.get(&TypeId::of::<V>())
.map(|v| v.downcast_ref::<V>().unwrap())
}
/// Inserts a new instance of the specified type.
///
/// Requires that this type has not been inserted before.
pub fn insert<V: Any>(&mut self, value: V) {
assert!(self
.values
.insert(TypeId::of::<V>(), Box::new(value))
.is_none());
}
}
#[cfg(test)]
mod tests {
use super::*;
struct TestTypeA;
impl TestTypeA {
fn get_a(&self) -> &'static str {
"a"
}
}
struct TestTypeB;
impl TestTypeB {
fn get_b(&self) -> &'static str {
"b"
}
}
#[test]
fn test_empty() {
let extensions_map = ExtensionsMap::empty();
assert!(extensions_map.get::<TestTypeA>().is_none());
assert!(extensions_map.get::<TestTypeB>().is_none());
}
#[test]
fn test_retrieval() {
let mut extensions_map = ExtensionsMap::empty();
extensions_map.insert(TestTypeA);
extensions_map.insert(TestTypeB);
assert_eq!(
extensions_map
.get::<TestTypeA>()
.map(|a| a.get_a())
.unwrap_or(""),
"a"
);
assert_eq!(
extensions_map
.get::<TestTypeB>()
.map(|b| b.get_b())
.unwrap_or(""),
"b"
);
}
}