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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /third_party/rust/unicode-width/src/lib.rs | |
parent | Initial commit. (diff) | |
download | firefox-esr-upstream.tar.xz firefox-esr-upstream.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/unicode-width/src/lib.rs')
-rw-r--r-- | third_party/rust/unicode-width/src/lib.rs | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/third_party/rust/unicode-width/src/lib.rs b/third_party/rust/unicode-width/src/lib.rs new file mode 100644 index 0000000000..1ee35c85d5 --- /dev/null +++ b/third_party/rust/unicode-width/src/lib.rs @@ -0,0 +1,131 @@ +// Copyright 2012-2015 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +//! Determine displayed width of `char` and `str` types according to +//! [Unicode Standard Annex #11](http://www.unicode.org/reports/tr11/) +//! rules. +//! +//! ```rust +//! extern crate unicode_width; +//! +//! use unicode_width::UnicodeWidthStr; +//! +//! fn main() { +//! let teststr = "Hello, world!"; +//! let width = UnicodeWidthStr::width(teststr); +//! println!("{}", teststr); +//! println!("The above string is {} columns wide.", width); +//! let width = teststr.width_cjk(); +//! println!("The above string is {} columns wide (CJK).", width); +//! } +//! ``` +//! +//! # features +//! +//! unicode-width supports a `no_std` feature. This eliminates dependence +//! on std, and instead uses equivalent functions from core. +//! +//! # crates.io +//! +//! You can use this package in your project by adding the following +//! to your `Cargo.toml`: +//! +//! ```toml +//! [dependencies] +//! unicode-width = "0.1.5" +//! ``` + +#![deny(missing_docs, unsafe_code)] +#![doc(html_logo_url = "https://unicode-rs.github.io/unicode-rs_sm.png", + html_favicon_url = "https://unicode-rs.github.io/unicode-rs_sm.png")] + +#![cfg_attr(feature = "bench", feature(test))] +#![no_std] + +#[cfg(test)] +#[macro_use] +extern crate std; + +#[cfg(feature = "bench")] +extern crate test; + +use tables::charwidth as cw; +pub use tables::UNICODE_VERSION; + +use core::ops::Add; + +mod tables; + +#[cfg(test)] +mod tests; + +/// Methods for determining displayed width of Unicode characters. +pub trait UnicodeWidthChar { + /// Returns the character's displayed width in columns, or `None` if the + /// character is a control character other than `'\x00'`. + /// + /// This function treats characters in the Ambiguous category according + /// to [Unicode Standard Annex #11](http://www.unicode.org/reports/tr11/) + /// as 1 column wide. This is consistent with the recommendations for non-CJK + /// contexts, or when the context cannot be reliably determined. + fn width(self) -> Option<usize>; + + /// Returns the character's displayed width in columns, or `None` if the + /// character is a control character other than `'\x00'`. + /// + /// This function treats characters in the Ambiguous category according + /// to [Unicode Standard Annex #11](http://www.unicode.org/reports/tr11/) + /// as 2 columns wide. This is consistent with the recommendations for + /// CJK contexts. + fn width_cjk(self) -> Option<usize>; +} + +impl UnicodeWidthChar for char { + #[inline] + fn width(self) -> Option<usize> { cw::width(self, false) } + + #[inline] + fn width_cjk(self) -> Option<usize> { cw::width(self, true) } +} + +/// Methods for determining displayed width of Unicode strings. +pub trait UnicodeWidthStr { + /// Returns the string's displayed width in columns. + /// + /// Control characters are treated as having zero width. + /// + /// This function treats characters in the Ambiguous category according + /// to [Unicode Standard Annex #11](http://www.unicode.org/reports/tr11/) + /// as 1 column wide. This is consistent with the recommendations for + /// non-CJK contexts, or when the context cannot be reliably determined. + fn width<'a>(&'a self) -> usize; + + /// Returns the string's displayed width in columns. + /// + /// Control characters are treated as having zero width. + /// + /// This function treats characters in the Ambiguous category according + /// to [Unicode Standard Annex #11](http://www.unicode.org/reports/tr11/) + /// as 2 column wide. This is consistent with the recommendations for + /// CJK contexts. + fn width_cjk<'a>(&'a self) -> usize; +} + +impl UnicodeWidthStr for str { + #[inline] + fn width(&self) -> usize { + self.chars().map(|c| cw::width(c, false).unwrap_or(0)).fold(0, Add::add) + } + + #[inline] + fn width_cjk(&self) -> usize { + self.chars().map(|c| cw::width(c, true).unwrap_or(0)).fold(0, Add::add) + } +} |