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diff --git a/third_party/rust/unicode-width/src/lib.rs b/third_party/rust/unicode-width/src/lib.rs
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+// 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)
+    }
+}