token_string/
error.rs

1// SPDX-FileCopyrightText: Copyright (C) 2024 Roland Csaszar
2// SPDX-License-Identifier: MPL-2.0
3//
4// Project:  token-string
5// File:     error.rs
6// Date:     22.Nov.2024
7// =============================================================================
8//! All errors of this crate.
9
10use core::{error, fmt, str};
11
12use crate::MAX_LENGTH;
13
14#[non_exhaustive]
15#[derive(Debug, PartialEq, Eq)]
16/// The possible errors of this crate.
17pub enum TkStrError {
18	/// Cannot create a [`crate::TokenString`], the length would be bigger than
19	/// [`MAX_LENGTH`].
20	TooBig(usize),
21	/// An error occurred encoding or decoding UTF-8 bytes.
22	UnicodeError(str::Utf8Error),
23	/// The index is out of bounds.
24	OutOfBounds(usize),
25	/// Too many strings are being concatenated, the [`crate::Builder`] has been
26	/// configured for less.
27	TooMany(usize),
28}
29
30impl fmt::Display for TkStrError {
31	fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
32		match *self {
33			| Self::TooBig(n) => write!(
34				f,
35				"TokenString would be bigger than MAX_LENGTH, {n} > \
36				 {MAX_LENGTH}"
37			),
38			| Self::UnicodeError(utf8_error) =>
39				write!(f, "encoding TokenString: {utf8_error}"),
40			| Self::OutOfBounds(i) => write!(f, "index {i} is out of bounds"),
41
42			| Self::TooMany(n) => write!(
43				f,
44				"too many strings concatenated, Builder has been configured \
45				 for {n} strings"
46			),
47		}
48	}
49}
50
51impl error::Error for TkStrError {}
52
53#[cfg(test)]
54mod err_tests {
55	#![expect(
56		clippy::std_instead_of_alloc,
57		reason = "We are testing, this needs std"
58	)]
59	extern crate std;
60
61	use std::string::ToString as _;
62
63	use assert2::check;
64
65	use crate::TkStrError;
66
67	#[test]
68	fn string_too_big() {
69		check!(
70			TkStrError::TooBig(5).to_string()
71				== "TokenString would be bigger than MAX_LENGTH, 5 > 65535"
72		);
73	}
74
75	#[test]
76	fn string_out_of_bounds() {
77		check!(
78			TkStrError::OutOfBounds(5).to_string()
79				== "index 5 is out of bounds"
80		);
81	}
82
83	#[test]
84	fn string_too_many() {
85		check!(
86			TkStrError::TooMany(5).to_string()
87				== "too many strings concatenated, Builder has been \
88				    configured for 5 strings"
89		);
90	}
91}
token_string/error.rs

token_string/
error.rs
