icu_pattern/frontend/
zerovec.rs

1// This file is part of ICU4X. For terms of use, please see the file
2// called LICENSE at the top level of the ICU4X source tree
3// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
4
5use crate::{Pattern, PatternBackend};
6
7use alloc::boxed::Box;
8use zerovec::{
9    maps::ZeroMapKV,
10    ule::{UleError, VarULE},
11    VarZeroSlice, VarZeroVec,
12};
13
14impl<'a, B: PatternBackend> ZeroMapKV<'a> for Pattern<B>
15where
16    Pattern<B>: VarULE,
17{
18    type Container = VarZeroVec<'a, Pattern<B>>;
19    type Slice = VarZeroSlice<Pattern<B>>;
20    type GetType = Pattern<B>;
21    type OwnedType = Box<Pattern<B>>;
22}
23
24/// Implement `VarULE` for `Pattern<SinglePlaceholder, str>`.
25///
26/// # Safety
27///
28/// Safety checklist for `ULE`:
29///
30/// 1. `Pattern<B>` does not include any uninitialized or padding bytes.
31/// 2. `Pattern<B>` is aligned to 1 byte.
32/// 3. The implementation of `validate_bytes()` returns an error
33///    if any byte is not valid.
34/// 4. The implementation of `validate_bytes()` returns an error
35///    if the slice cannot be used to build a `Pattern<B>` in its entirety.
36/// 5. The implementation of `from_bytes_unchecked()` returns a reference to the same data.
37/// 6. `parse_bytes()` is equivalent to `validate_bytes()` followed by `from_bytes_unchecked()`.
38/// 7. `Pattern<B>` byte equality is semantic equality.
39unsafe impl<B, S: ?Sized + VarULE> VarULE for Pattern<B>
40where
41    B: PatternBackend<Store = S>,
42{
43    fn validate_bytes(bytes: &[u8]) -> Result<(), UleError> {
44        let store = S::parse_bytes(bytes)?;
45        B::validate_store(store).map_err(|_| UleError::parse::<Self>())
46    }
47
48    unsafe fn from_bytes_unchecked(bytes: &[u8]) -> &Self {
49        let store = S::from_bytes_unchecked(bytes);
50        Self::from_ref_store_unchecked(store)
51    }
52}
53
54#[cfg(test)]
55mod tests {
56    use super::*;
57    use crate::SinglePlaceholderPattern;
58    use litemap::LiteMap;
59    use zerovec::ZeroMap;
60
61    #[test]
62    fn test_zeromap() {
63        let pattern =
64            SinglePlaceholderPattern::try_from_str("Hello, {0}!", Default::default()).unwrap();
65        let mut litemap = LiteMap::<u32, Box<SinglePlaceholderPattern>>::new_vec();
66        litemap.insert(0, pattern.clone());
67        let zeromap = ZeroMap::<u32, SinglePlaceholderPattern>::from_iter(litemap);
68        let recovered_pattern = zeromap.get(&0).unwrap();
69        assert_eq!(&*pattern, recovered_pattern);
70    }
71}
icu_pattern/frontend/zerovec.rs

icu_pattern/frontend/
zerovec.rs
