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diff --git a/third_party/rust/tinystr/src/ule.rs b/third_party/rust/tinystr/src/ule.rs
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+// This file is part of ICU4X. For terms of use, please see the file
+// called LICENSE at the top level of the ICU4X source tree
+// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
+
+use crate::{TinyAsciiStr, UnvalidatedTinyAsciiStr};
+use zerovec::maps::ZeroMapKV;
+use zerovec::ule::*;
+use zerovec::{ZeroSlice, ZeroVec};
+
+// Safety (based on the safety checklist on the ULE trait):
+// 1. TinyAsciiStr does not include any uninitialized or padding bytes.
+// (achieved by `#[repr(transparent)]` on a type that satisfies this invariant)
+// 2. TinyAsciiStr is aligned to 1 byte.
+// (achieved by `#[repr(transparent)]` on a type that satisfies this invariant)
+// 3. The impl of validate_byte_slice() returns an error if any byte is not valid.
+// 4. The impl of validate_byte_slice() returns an error if there are extra bytes.
+// 5. The other ULE methods use the default impl.
+// 6. TinyAsciiStr byte equality is semantic equality
+unsafe impl<const N: usize> ULE for TinyAsciiStr<N> {
+ #[inline]
+ fn validate_byte_slice(bytes: &[u8]) -> Result<(), ZeroVecError> {
+ if bytes.len() % N != 0 {
+ return Err(ZeroVecError::length::<Self>(bytes.len()));
+ }
+ // Validate the bytes
+ for chunk in bytes.chunks_exact(N) {
+ let _ = TinyAsciiStr::<N>::from_bytes_inner(chunk, 0, N, true)
+ .map_err(|_| ZeroVecError::parse::<Self>())?;
+ }
+ Ok(())
+ }
+}
+
+impl<const N: usize> AsULE for TinyAsciiStr<N> {
+ type ULE = Self;
+
+ #[inline]
+ fn to_unaligned(self) -> Self::ULE {
+ self
+ }
+
+ #[inline]
+ fn from_unaligned(unaligned: Self::ULE) -> Self {
+ unaligned
+ }
+}
+
+impl<'a, const N: usize> ZeroMapKV<'a> for TinyAsciiStr<N> {
+ type Container = ZeroVec<'a, TinyAsciiStr<N>>;
+ type Slice = ZeroSlice<TinyAsciiStr<N>>;
+ type GetType = TinyAsciiStr<N>;
+ type OwnedType = TinyAsciiStr<N>;
+}
+
+// Safety (based on the safety checklist on the ULE trait):
+// 1. UnvalidatedTinyAsciiStr does not include any uninitialized or padding bytes.
+// (achieved by `#[repr(transparent)]` on a type that satisfies this invariant)
+// 2. UnvalidatedTinyAsciiStr is aligned to 1 byte.
+// (achieved by `#[repr(transparent)]` on a type that satisfies this invariant)
+// 3. The impl of validate_byte_slice() returns an error if any byte is not valid.
+// 4. The impl of validate_byte_slice() returns an error if there are extra bytes.
+// 5. The other ULE methods use the default impl.
+// 6. UnvalidatedTinyAsciiStr byte equality is semantic equality
+unsafe impl<const N: usize> ULE for UnvalidatedTinyAsciiStr<N> {
+ #[inline]
+ fn validate_byte_slice(bytes: &[u8]) -> Result<(), ZeroVecError> {
+ if bytes.len() % N != 0 {
+ return Err(ZeroVecError::length::<Self>(bytes.len()));
+ }
+ Ok(())
+ }
+}
+
+impl<const N: usize> AsULE for UnvalidatedTinyAsciiStr<N> {
+ type ULE = Self;
+
+ #[inline]
+ fn to_unaligned(self) -> Self::ULE {
+ self
+ }
+
+ #[inline]
+ fn from_unaligned(unaligned: Self::ULE) -> Self {
+ unaligned
+ }
+}
+
+impl<'a, const N: usize> ZeroMapKV<'a> for UnvalidatedTinyAsciiStr<N> {
+ type Container = ZeroVec<'a, UnvalidatedTinyAsciiStr<N>>;
+ type Slice = ZeroSlice<UnvalidatedTinyAsciiStr<N>>;
+ type GetType = UnvalidatedTinyAsciiStr<N>;
+ type OwnedType = UnvalidatedTinyAsciiStr<N>;
+}
+
+#[cfg(test)]
+mod test {
+ use crate::*;
+ use zerovec::*;
+
+ #[test]
+ fn test_zerovec() {
+ let mut vec = ZeroVec::<TinyAsciiStr<7>>::new();
+
+ vec.with_mut(|v| v.push("foobar".parse().unwrap()));
+ vec.with_mut(|v| v.push("baz".parse().unwrap()));
+ vec.with_mut(|v| v.push("quux".parse().unwrap()));
+
+ let bytes = vec.as_bytes();
+
+ let vec: ZeroVec<TinyAsciiStr<7>> = ZeroVec::parse_byte_slice(bytes).unwrap();
+
+ assert_eq!(&*vec.get(0).unwrap(), "foobar");
+ assert_eq!(&*vec.get(1).unwrap(), "baz");
+ assert_eq!(&*vec.get(2).unwrap(), "quux");
+ }
+}