rgb_lightning/util/
string.rs

1// This file is Copyright its original authors, visible in version control
2// history.
3//
4// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7// You may not use this file except in accordance with one or both of these
8// licenses.
9
10//! Utilities for strings.
11
12use core::fmt;
13
14/// A string that displays only printable characters, replacing control characters with
15/// [`core::char::REPLACEMENT_CHARACTER`].
16#[derive(Debug, PartialEq)]
17pub struct PrintableString<'a>(pub &'a str);
18
19impl<'a> fmt::Display for PrintableString<'a> {
20	fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
21		use core::fmt::Write;
22		for c in self.0.chars() {
23			let c = if c.is_control() { core::char::REPLACEMENT_CHARACTER } else { c };
24			f.write_char(c)?;
25		}
26
27		Ok(())
28	}
29}
30
31#[cfg(test)]
32mod tests {
33	use super::PrintableString;
34
35	#[test]
36	fn displays_printable_string() {
37		assert_eq!(
38			format!("{}", PrintableString("I \u{1F496} LDK!\t\u{26A1}")),
39			"I \u{1F496} LDK!\u{FFFD}\u{26A1}",
40		);
41	}
42}
rgb_lightning/util/string.rs

rgb_lightning/util/
string.rs
