facet_core/impls_alloc/
btreemap.rs

1use core::write;
2
3use alloc::{
4    boxed::Box,
5    collections::{BTreeMap, VecDeque},
6};
7
8use crate::{
9    Def, Facet, MapDef, MapIterVTable, MapVTable, MarkerTraits, PtrConst, PtrMut, Shape,
10    VTableView, ValueVTable,
11};
12
13struct BTreeMapIterator<'mem, K> {
14    map: PtrConst<'mem>,
15    keys: VecDeque<&'mem K>,
16}
17
18unsafe impl<'a, K, V> Facet<'a> for BTreeMap<K, V>
19where
20    K: Facet<'a> + core::cmp::Eq + core::cmp::Ord,
21    V: Facet<'a>,
22{
23    const SHAPE: &'static crate::Shape = &const {
24        Shape::builder_for_sized::<Self>()
25            .type_params(&[
26                crate::TypeParam {
27                    name: "K",
28                    shape: || K::SHAPE,
29                },
30                crate::TypeParam {
31                    name: "V",
32                    shape: || V::SHAPE,
33                },
34            ])
35            .vtable(
36                &const {
37                    let mut builder = ValueVTable::builder::<Self>()
38                        .marker_traits({
39                            let arg_dependent_traits = MarkerTraits::SEND
40                                .union(MarkerTraits::SYNC)
41                                .union(MarkerTraits::EQ);
42                            arg_dependent_traits
43                                .intersection(V::SHAPE.vtable.marker_traits)
44                                .intersection(K::SHAPE.vtable.marker_traits)
45                                // only depends on `A` which we are not generic over (yet)
46                                .union(MarkerTraits::UNPIN)
47                        })
48                        .type_name(|f, opts| {
49                            if let Some(opts) = opts.for_children() {
50                                write!(f, "BTreeMap<")?;
51                                (K::SHAPE.vtable.type_name)(f, opts)?;
52                                write!(f, ", ")?;
53                                (V::SHAPE.vtable.type_name)(f, opts)?;
54                                write!(f, ">")
55                            } else {
56                                write!(f, "BTreeMap<⋯>")
57                            }
58                        });
59
60                    if K::SHAPE.vtable.debug.is_some() && V::SHAPE.vtable.debug.is_some() {
61                        builder = builder.debug(|value, f| {
62                            let k_debug = <VTableView<K>>::of().debug().unwrap();
63                            let v_debug = <VTableView<V>>::of().debug().unwrap();
64                            write!(f, "{{")?;
65                            for (i, (key, val)) in value.iter().enumerate() {
66                                if i > 0 {
67                                    write!(f, ", ")?;
68                                }
69                                (k_debug)(key, f)?;
70                                write!(f, ": ")?;
71                                (v_debug)(val, f)?;
72                            }
73                            write!(f, "}}")
74                        })
75                    }
76
77                    builder =
78                        builder.default_in_place(|target| unsafe { target.put(Self::default()) });
79                    // FIXME: VERY MUCH INCORRECt
80                    builder =
81                        builder.clone_into(|src, dst| unsafe { dst.put(core::ptr::read(src)) });
82
83                    if V::SHAPE.vtable.eq.is_some() {
84                        builder = builder.eq(|a, b| {
85                            let v_eq = <VTableView<V>>::of().eq().unwrap();
86                            a.len() == b.len()
87                                && a.iter().all(|(key_a, val_a)| {
88                                    b.get(key_a).is_some_and(|val_b| (v_eq)(val_a, val_b))
89                                })
90                        });
91                    }
92
93                    if K::SHAPE.vtable.hash.is_some() && V::SHAPE.vtable.hash.is_some() {
94                        builder = builder.hash(|map, hasher_this, hasher_write_fn| unsafe {
95                            use crate::HasherProxy;
96                            use core::hash::Hash;
97
98                            let k_hash = <VTableView<K>>::of().hash().unwrap();
99                            let v_hash = <VTableView<V>>::of().hash().unwrap();
100                            let mut hasher = HasherProxy::new(hasher_this, hasher_write_fn);
101                            map.len().hash(&mut hasher);
102                            for (k, v) in map {
103                                (k_hash)(k, hasher_this, hasher_write_fn);
104                                (v_hash)(v, hasher_this, hasher_write_fn);
105                            }
106                        });
107                    }
108
109                    builder.build()
110                },
111            )
112            .def(Def::Map(
113                MapDef::builder()
114                    .k(K::SHAPE)
115                    .v(V::SHAPE)
116                    .vtable(
117                        &const {
118                            MapVTable::builder()
119                                .init_in_place_with_capacity(|uninit, _capacity| unsafe {
120                                    uninit.put(Self::new())
121                                })
122                                .insert(|ptr, key, value| unsafe {
123                                    let map = ptr.as_mut::<Self>();
124                                    let k = key.read::<K>();
125                                    let v = value.read::<V>();
126                                    map.insert(k, v);
127                                })
128                                .len(|ptr| unsafe {
129                                    let map = ptr.get::<Self>();
130                                    map.len()
131                                })
132                                .contains_key(|ptr, key| unsafe {
133                                    let map = ptr.get::<Self>();
134                                    map.contains_key(key.get())
135                                })
136                                .get_value_ptr(|ptr, key| unsafe {
137                                    let map = ptr.get::<Self>();
138                                    map.get(key.get()).map(|v| PtrConst::new(v as *const _))
139                                })
140                                .iter(|ptr| unsafe {
141                                    let map = ptr.get::<Self>();
142                                    let keys: VecDeque<&K> = map.keys().collect();
143                                    let iter_state = Box::new(BTreeMapIterator { map: ptr, keys });
144                                    PtrMut::new(Box::into_raw(iter_state) as *mut u8)
145                                })
146                                .iter_vtable(
147                                    MapIterVTable::builder()
148                                        .next(|iter_ptr| unsafe {
149                                            let state =
150                                                iter_ptr.as_mut::<BTreeMapIterator<'_, K>>();
151                                            let map = state.map.get::<Self>();
152                                            while let Some(key) = state.keys.pop_front() {
153                                                if let Some(value) = map.get(key) {
154                                                    return Some((
155                                                        PtrConst::new(key as *const K),
156                                                        PtrConst::new(value as *const V),
157                                                    ));
158                                                }
159                                            }
160
161                                            None
162                                        })
163                                        .dealloc(|iter_ptr| unsafe {
164                                            drop(Box::from_raw(
165                                                iter_ptr.as_ptr::<BTreeMapIterator<'_, K>>()
166                                                    as *mut BTreeMapIterator<'_, K>,
167                                            ))
168                                        })
169                                        .build(),
170                                )
171                                .build()
172                        },
173                    )
174                    .build(),
175            ))
176            .build()
177    };
178}
facet_core/impls_alloc/btreemap.rs

facet_core/impls_alloc/
btreemap.rs
