bump_scope/from_utf8_error.rs
1use core::{error::Error, fmt, ops::Deref, str::Utf8Error};
2
3/// A possible error value when converting a string from a UTF-8 byte vector.
4///
5/// This type is the error type for [`BumpString::from_utf8`](crate::BumpString::from_utf8), [`MutBumpString::from_utf8`](crate::MutBumpString::from_utf8) and [`BumpBox<str>::from_utf8`](crate::BumpBox::from_utf8). It
6/// is designed in such a way to carefully avoid reallocations: the
7/// [`into_bytes`](FromUtf8Error::into_bytes) method will give back the byte vector that was used in the
8/// conversion attempt.
9///
10/// The [`Utf8Error`] type provided by [`std::str`] represents an error that may
11/// occur when converting a slice of [`u8`]s to a [`&str`]. In this sense, it's
12/// an analogue to `FromUtf8Error`, and you can get one from a `FromUtf8Error`
13/// through the [`utf8_error`] method.
14///
15/// [`Utf8Error`]: core::str::Utf8Error
16/// [`std::str`]: core::str "std::str"
17/// [`&str`]: prim@str "&str"
18/// [`utf8_error`]: FromUtf8Error::utf8_error
19#[derive(Debug, PartialEq, Eq)]
20#[cfg_attr(feature = "panic-on-alloc", derive(Clone))]
21pub struct FromUtf8Error<Bytes> {
22 bytes: Bytes,
23 error: Utf8Error,
24}
25
26impl<Bytes> FromUtf8Error<Bytes> {
27 #[inline(always)]
28 pub(crate) const fn new(error: Utf8Error, bytes: Bytes) -> Self {
29 Self { bytes, error }
30 }
31
32 /// Returns a slice of [`u8`]s bytes that were attempted to convert to a `String`.
33 #[must_use]
34 #[inline(always)]
35 pub fn as_bytes(&self) -> &[u8]
36 where
37 Bytes: Deref<Target = [u8]>,
38 {
39 &self.bytes
40 }
41
42 /// Returns the bytes that were attempted to convert to a `String`.
43 #[must_use = "`self` will be dropped if the result is not used"]
44 #[inline(always)]
45 pub fn into_bytes(self) -> Bytes {
46 self.bytes
47 }
48
49 /// Fetch a `Utf8Error` to get more details about the conversion failure.
50 ///
51 /// The [`Utf8Error`] type provided by [`std::str`] represents an error that may
52 /// occur when converting a slice of [`u8`]s to a [`&str`]. In this sense, it's
53 /// an analogue to `FromUtf8Error`. See its documentation for more details
54 /// on using it.
55 ///
56 /// [`std::str`]: core::str "std::str"
57 /// [`&str`]: prim@str "&str"
58 #[inline(always)]
59 pub fn utf8_error(&self) -> Utf8Error {
60 self.error
61 }
62}
63
64impl<Bytes> fmt::Display for FromUtf8Error<Bytes> {
65 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
66 fmt::Display::fmt(&self.error, f)
67 }
68}
69
70impl<Bytes: fmt::Debug> Error for FromUtf8Error<Bytes> {}