Repository: rust
Issue: Tracking Issue for explicit-endian String::from_utf16
Labels: T-libs-api,C-tracking-issue

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Feature gate: `#![feature(str_from_utf16_endian)]`

This is a tracking issue for versions of `String::from_utf16` which take `&[u8]` and use a specific endianness.

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### Public API

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```rust
impl String {
    fn from_utf16le(v: &[u8]) -> Result<String, FromUtf16Error>;
    fn from_utf16le_lossy(v: &[u8]) -> String;
    fn from_utf16be(v: &[u8]) -> Result<String, FromUtf16Error>;
    fn from_utf16be_lossy(v: &[u8]) -> String;
}
```

### Steps / History

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- [x] Implementation: #95967
- [ ] Final comment period (FCP)[^1]
- [ ] Stabilization PR

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### Unresolved Questions

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- [ ] Ideal naming; options include `from_utf16le`, `from_utf16_le`, `from_le_utf16`, `from_le_utf16_bytes`, and other such combinations.
- [ ] Should these methods get the `with_capacity`+`push` implementation used for `from_utf16` while `collect` doesn't reserve capacity? (#48994)
- [ ] Tweaks to the error type: `FromUtf16Error` currently displays as `"invalid utf-16: lone surrogate found"` which isn't correct for an error due to odd byte length.

[^1]: https://std-dev-guide.rust-lang.org/feature-lifecycle/stabilization.html