| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/registry/src/github.com-1ecc6299db9ec823/unicode-bidi-0.3.13/src/prepare.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>prepare.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../normalize.css"><link rel="stylesheet" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../ayu.css" disabled><link rel="stylesheet" href="../../dark.css" disabled><link rel="stylesheet" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="../../source-script.js"></script><script defer src="../../source-files.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../unicode_bidi/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../unicode_bidi/index.html"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="comment">// Copyright 2015 The Servo Project Developers. See the |
| // COPYRIGHT file at the top-level directory of this distribution. |
| // |
| // 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. |
| |
| </span><span class="doccomment">//! 3.3.3 Preparations for Implicit Processing |
| //! |
| //! <http://www.unicode.org/reports/tr9/#Preparations_for_Implicit_Processing> |
| |
| </span><span class="kw">use </span>alloc::vec::Vec; |
| <span class="kw">use </span>core::cmp::max; |
| <span class="kw">use </span>core::ops::Range; |
| |
| <span class="kw">use </span><span class="kw">super</span>::level::Level; |
| <span class="kw">use </span><span class="kw">super</span>::BidiClass::{<span class="self">self</span>, <span class="kw-2">*</span>}; |
| |
| <span class="doccomment">/// A maximal substring of characters with the same embedding level. |
| /// |
| /// Represented as a range of byte indices. |
| </span><span class="kw">pub type </span>LevelRun = Range<usize>; |
| |
| <span class="doccomment">/// Output of `isolating_run_sequences` (steps X9-X10) |
| </span><span class="attribute">#[derive(Debug, PartialEq)] |
| </span><span class="kw">pub struct </span>IsolatingRunSequence { |
| <span class="kw">pub </span>runs: Vec<LevelRun>, |
| <span class="kw">pub </span>sos: BidiClass, <span class="comment">// Start-of-sequence type. |
| </span><span class="kw">pub </span>eos: BidiClass, <span class="comment">// End-of-sequence type. |
| </span>} |
| |
| <span class="doccomment">/// Compute the set of isolating run sequences. |
| /// |
| /// An isolating run sequence is a maximal sequence of level runs such that for all level runs |
| /// except the last one in the sequence, the last character of the run is an isolate initiator |
| /// whose matching PDI is the first character of the next level run in the sequence. |
| /// |
| /// Note: This function does *not* return the sequences in order by their first characters. |
| </span><span class="attribute">#[cfg_attr(feature = <span class="string">"flame_it"</span>, flamer::flame)] |
| </span><span class="kw">pub fn </span>isolating_run_sequences( |
| para_level: Level, |
| original_classes: <span class="kw-2">&</span>[BidiClass], |
| levels: <span class="kw-2">&</span>[Level], |
| ) -> Vec<IsolatingRunSequence> { |
| <span class="kw">let </span>runs = level_runs(levels, original_classes); |
| |
| <span class="comment">// Compute the set of isolating run sequences. |
| // <http://www.unicode.org/reports/tr9/#BD13> |
| </span><span class="kw">let </span><span class="kw-2">mut </span>sequences = Vec::with_capacity(runs.len()); |
| |
| <span class="comment">// When we encounter an isolate initiator, we push the current sequence onto the |
| // stack so we can resume it after the matching PDI. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>stack = <span class="macro">vec!</span>[Vec::new()]; |
| |
| <span class="kw">for </span>run <span class="kw">in </span>runs { |
| <span class="macro">assert!</span>(run.len() > <span class="number">0</span>); |
| <span class="macro">assert!</span>(!stack.is_empty()); |
| |
| <span class="kw">let </span>start_class = original_classes[run.start]; |
| <span class="kw">let </span>end_class = original_classes[run.end - <span class="number">1</span>]; |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>sequence = <span class="kw">if </span>start_class == PDI && stack.len() > <span class="number">1 </span>{ |
| <span class="comment">// Continue a previous sequence interrupted by an isolate. |
| </span>stack.pop().unwrap() |
| } <span class="kw">else </span>{ |
| <span class="comment">// Start a new sequence. |
| </span>Vec::new() |
| }; |
| |
| sequence.push(run); |
| |
| <span class="kw">if let </span>RLI | LRI | FSI = end_class { |
| <span class="comment">// Resume this sequence after the isolate. |
| </span>stack.push(sequence); |
| } <span class="kw">else </span>{ |
| <span class="comment">// This sequence is finished. |
| </span>sequences.push(sequence); |
| } |
| } |
| <span class="comment">// Pop any remaning sequences off the stack. |
| </span>sequences.extend(stack.into_iter().rev().filter(|seq| !seq.is_empty())); |
| |
| <span class="comment">// Determine the `sos` and `eos` class for each sequence. |
| // <http://www.unicode.org/reports/tr9/#X10> |
| </span>sequences |
| .into_iter() |
| .map(|sequence: Vec<LevelRun>| { |
| <span class="macro">assert!</span>(!sequence.is_empty()); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>result = IsolatingRunSequence { |
| runs: sequence, |
| sos: L, |
| eos: L, |
| }; |
| |
| <span class="kw">let </span>start_of_seq = result.runs[<span class="number">0</span>].start; |
| <span class="kw">let </span>runs_len = result.runs.len(); |
| <span class="kw">let </span>end_of_seq = result.runs[runs_len - <span class="number">1</span>].end; |
| |
| <span class="comment">// > (not counting characters removed by X9) |
| </span><span class="kw">let </span>seq_level = result |
| .iter_forwards_from(start_of_seq, <span class="number">0</span>) |
| .filter(|i| not_removed_by_x9(<span class="kw-2">&</span>original_classes[<span class="kw-2">*</span>i])) |
| .map(|i| levels[i]) |
| .next() |
| .unwrap_or(levels[start_of_seq]); |
| |
| <span class="comment">// XXXManishearth the spec talks of a start and end level, |
| // but for a given IRS the two should be equivalent, yes? |
| </span><span class="kw">let </span>end_level = result |
| .iter_backwards_from(end_of_seq, runs_len - <span class="number">1</span>) |
| .filter(|i| not_removed_by_x9(<span class="kw-2">&</span>original_classes[<span class="kw-2">*</span>i])) |
| .map(|i| levels[i]) |
| .next() |
| .unwrap_or(levels[end_of_seq - <span class="number">1</span>]); |
| |
| <span class="attribute">#[cfg(test)] |
| </span><span class="kw">for </span>run <span class="kw">in </span>result.runs.clone() { |
| <span class="kw">for </span>idx <span class="kw">in </span>run { |
| <span class="kw">if </span>not_removed_by_x9(<span class="kw-2">&</span>original_classes[idx]) { |
| <span class="macro">assert_eq!</span>(seq_level, levels[idx]); |
| } |
| } |
| } |
| |
| <span class="comment">// Get the level of the last non-removed char before the runs. |
| </span><span class="kw">let </span>pred_level = <span class="kw">match </span>original_classes[..start_of_seq] |
| .iter() |
| .rposition(not_removed_by_x9) |
| { |
| <span class="prelude-val">Some</span>(idx) => levels[idx], |
| <span class="prelude-val">None </span>=> para_level, |
| }; |
| |
| <span class="comment">// Get the last non-removed character to check if it is an isolate initiator. |
| // The spec calls for an unmatched one, but matched isolate initiators |
| // will never be at the end of a level run (otherwise there would be more to the run). |
| // We unwrap_or(BN) because BN marks removed classes and it won't matter for the check. |
| </span><span class="kw">let </span>last_non_removed = original_classes[..end_of_seq] |
| .iter() |
| .copied() |
| .rev() |
| .find(not_removed_by_x9) |
| .unwrap_or(BN); |
| |
| <span class="comment">// Get the level of the next non-removed char after the runs. |
| </span><span class="kw">let </span>succ_level = <span class="kw">if let </span>RLI | LRI | FSI = last_non_removed { |
| para_level |
| } <span class="kw">else </span>{ |
| <span class="kw">match </span>original_classes[end_of_seq..] |
| .iter() |
| .position(not_removed_by_x9) |
| { |
| <span class="prelude-val">Some</span>(idx) => levels[end_of_seq + idx], |
| <span class="prelude-val">None </span>=> para_level, |
| } |
| }; |
| |
| result.sos = max(seq_level, pred_level).bidi_class(); |
| result.eos = max(end_level, succ_level).bidi_class(); |
| result |
| }) |
| .collect() |
| } |
| |
| <span class="kw">impl </span>IsolatingRunSequence { |
| <span class="doccomment">/// Returns the full range of text represented by this isolating run sequence |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>text_range(<span class="kw-2">&</span><span class="self">self</span>) -> Range<usize> { |
| <span class="kw">if let </span>(<span class="prelude-val">Some</span>(start), <span class="prelude-val">Some</span>(end)) = (<span class="self">self</span>.runs.first(), <span class="self">self</span>.runs.last()) { |
| start.start..end.end |
| } <span class="kw">else </span>{ |
| <span class="kw">return </span><span class="number">0</span>..<span class="number">0</span>; |
| } |
| } |
| |
| <span class="doccomment">/// Given a text-relative position `pos` and an index of the level run it is in, |
| /// produce an iterator of all characters after and pos (`pos..`) that are in this |
| /// run sequence |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>iter_forwards_from( |
| <span class="kw-2">&</span><span class="self">self</span>, |
| pos: usize, |
| level_run_index: usize, |
| ) -> <span class="kw">impl </span>Iterator<Item = usize> + <span class="lifetime">'_ </span>{ |
| <span class="kw">let </span>runs = <span class="kw-2">&</span><span class="self">self</span>.runs[level_run_index..]; |
| |
| <span class="comment">// Check that it is in range |
| // (we can't use contains() since we want an inclusive range) |
| </span><span class="attribute">#[cfg(feature = <span class="string">"std"</span>)] |
| </span><span class="macro">debug_assert!</span>(runs[<span class="number">0</span>].start <= pos && pos <= runs[<span class="number">0</span>].end); |
| |
| (pos..runs[<span class="number">0</span>].end).chain(runs[<span class="number">1</span>..].iter().flat_map(Clone::clone)) |
| } |
| |
| <span class="doccomment">/// Given a text-relative position `pos` and an index of the level run it is in, |
| /// produce an iterator of all characters before and excludingpos (`..pos`) that are in this |
| /// run sequence |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>iter_backwards_from( |
| <span class="kw-2">&</span><span class="self">self</span>, |
| pos: usize, |
| level_run_index: usize, |
| ) -> <span class="kw">impl </span>Iterator<Item = usize> + <span class="lifetime">'_ </span>{ |
| <span class="kw">let </span>prev_runs = <span class="kw-2">&</span><span class="self">self</span>.runs[..level_run_index]; |
| <span class="kw">let </span>current = <span class="kw-2">&</span><span class="self">self</span>.runs[level_run_index]; |
| |
| <span class="comment">// Check that it is in range |
| // (we can't use contains() since we want an inclusive range) |
| </span><span class="attribute">#[cfg(feature = <span class="string">"std"</span>)] |
| </span><span class="macro">debug_assert!</span>(current.start <= pos && pos <= current.end); |
| |
| (current.start..pos) |
| .rev() |
| .chain(prev_runs.iter().rev().flat_map(Clone::clone)) |
| } |
| } |
| |
| <span class="doccomment">/// Finds the level runs in a paragraph. |
| /// |
| /// <http://www.unicode.org/reports/tr9/#BD7> |
| </span><span class="kw">fn </span>level_runs(levels: <span class="kw-2">&</span>[Level], original_classes: <span class="kw-2">&</span>[BidiClass]) -> Vec<LevelRun> { |
| <span class="macro">assert_eq!</span>(levels.len(), original_classes.len()); |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>runs = Vec::new(); |
| <span class="kw">if </span>levels.is_empty() { |
| <span class="kw">return </span>runs; |
| } |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>current_run_level = levels[<span class="number">0</span>]; |
| <span class="kw">let </span><span class="kw-2">mut </span>current_run_start = <span class="number">0</span>; |
| <span class="kw">for </span>i <span class="kw">in </span><span class="number">1</span>..levels.len() { |
| <span class="kw">if </span>!removed_by_x9(original_classes[i]) && levels[i] != current_run_level { |
| <span class="comment">// End the last run and start a new one. |
| </span>runs.push(current_run_start..i); |
| current_run_level = levels[i]; |
| current_run_start = i; |
| } |
| } |
| runs.push(current_run_start..levels.len()); |
| |
| runs |
| } |
| |
| <span class="doccomment">/// Should this character be ignored in steps after X9? |
| /// |
| /// <http://www.unicode.org/reports/tr9/#X9> |
| </span><span class="kw">pub fn </span>removed_by_x9(class: BidiClass) -> bool { |
| <span class="kw">match </span>class { |
| RLE | LRE | RLO | LRO | PDF | BN => <span class="bool-val">true</span>, |
| <span class="kw">_ </span>=> <span class="bool-val">false</span>, |
| } |
| } |
| |
| <span class="comment">// For use as a predicate for `position` / `rposition` |
| </span><span class="kw">pub fn </span>not_removed_by_x9(class: <span class="kw-2">&</span>BidiClass) -> bool { |
| !removed_by_x9(<span class="kw-2">*</span>class) |
| } |
| |
| <span class="attribute">#[cfg(test)] |
| </span><span class="kw">mod </span>tests { |
| <span class="kw">use super</span>::<span class="kw-2">*</span>; |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_level_runs() { |
| <span class="macro">assert_eq!</span>(level_runs(<span class="kw-2">&</span>Level::vec(<span class="kw-2">&</span>[]), <span class="kw-2">&</span>[]), <span class="kw-2">&</span>[]); |
| <span class="macro">assert_eq!</span>( |
| level_runs(<span class="kw-2">&</span>Level::vec(<span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">2</span>, <span class="number">0</span>, <span class="number">0</span>]), <span class="kw-2">&</span>[L; <span class="number">8</span>]), |
| <span class="kw-2">&</span>[<span class="number">0</span>..<span class="number">3</span>, <span class="number">3</span>..<span class="number">5</span>, <span class="number">5</span>..<span class="number">6</span>, <span class="number">6</span>..<span class="number">8</span>] |
| ); |
| } |
| |
| <span class="comment">// From <http://www.unicode.org/reports/tr9/#BD13> |
| </span><span class="attribute">#[rustfmt::skip] |
| #[test] |
| </span><span class="kw">fn </span>test_isolating_run_sequences() { |
| |
| <span class="comment">// == Example 1 == |
| // text1·RLE·text2·PDF·RLE·text3·PDF·text4 |
| // index 0 1 2 3 4 5 6 7 |
| </span><span class="kw">let </span>classes = <span class="kw-2">&</span>[L, RLE, L, PDF, RLE, L, PDF, L]; |
| <span class="kw">let </span>levels = <span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">0</span>]; |
| <span class="kw">let </span>para_level = Level::ltr(); |
| <span class="kw">let </span><span class="kw-2">mut </span>sequences = isolating_run_sequences(para_level, classes, <span class="kw-2">&</span>Level::vec(levels)); |
| sequences.sort_by(|a, b| a.runs[<span class="number">0</span>].clone().cmp(b.runs[<span class="number">0</span>].clone())); |
| <span class="macro">assert_eq!</span>( |
| sequences.iter().map(|s| s.runs.clone()).collect::<Vec<<span class="kw">_</span>>>(), |
| <span class="macro">vec!</span>[<span class="macro">vec!</span>[<span class="number">0</span>..<span class="number">2</span>], <span class="macro">vec!</span>[<span class="number">2</span>..<span class="number">7</span>], <span class="macro">vec!</span>[<span class="number">7</span>..<span class="number">8</span>]] |
| ); |
| |
| <span class="comment">// == Example 2 == |
| // text1·RLI·text2·PDI·RLI·text3·PDI·text4 |
| // index 0 1 2 3 4 5 6 7 |
| </span><span class="kw">let </span>classes = <span class="kw-2">&</span>[L, RLI, L, PDI, RLI, L, PDI, L]; |
| <span class="kw">let </span>levels = <span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>]; |
| <span class="kw">let </span>para_level = Level::ltr(); |
| <span class="kw">let </span><span class="kw-2">mut </span>sequences = isolating_run_sequences(para_level, classes, <span class="kw-2">&</span>Level::vec(levels)); |
| sequences.sort_by(|a, b| a.runs[<span class="number">0</span>].clone().cmp(b.runs[<span class="number">0</span>].clone())); |
| <span class="macro">assert_eq!</span>( |
| sequences.iter().map(|s| s.runs.clone()).collect::<Vec<<span class="kw">_</span>>>(), |
| <span class="macro">vec!</span>[<span class="macro">vec!</span>[<span class="number">0</span>..<span class="number">2</span>, <span class="number">3</span>..<span class="number">5</span>, <span class="number">6</span>..<span class="number">8</span>], <span class="macro">vec!</span>[<span class="number">2</span>..<span class="number">3</span>], <span class="macro">vec!</span>[<span class="number">5</span>..<span class="number">6</span>]] |
| ); |
| |
| <span class="comment">// == Example 3 == |
| // text1·RLI·text2·LRI·text3·RLE·text4·PDF·text5·PDI·text6·PDI·text7 |
| // index 0 1 2 3 4 5 6 7 8 9 10 11 12 |
| </span><span class="kw">let </span>classes = <span class="kw-2">&</span>[L, RLI, L, LRI, L, RLE, L, PDF, L, PDI, L, PDI, L]; |
| <span class="kw">let </span>levels = <span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">3</span>, <span class="number">3</span>, <span class="number">2</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>]; |
| <span class="kw">let </span>para_level = Level::ltr(); |
| <span class="kw">let </span><span class="kw-2">mut </span>sequences = isolating_run_sequences(para_level, classes, <span class="kw-2">&</span>Level::vec(levels)); |
| sequences.sort_by(|a, b| a.runs[<span class="number">0</span>].clone().cmp(b.runs[<span class="number">0</span>].clone())); |
| <span class="macro">assert_eq!</span>( |
| sequences.iter().map(|s| s.runs.clone()).collect::<Vec<<span class="kw">_</span>>>(), |
| <span class="macro">vec!</span>[<span class="macro">vec!</span>[<span class="number">0</span>..<span class="number">2</span>, <span class="number">11</span>..<span class="number">13</span>], <span class="macro">vec!</span>[<span class="number">2</span>..<span class="number">4</span>, <span class="number">9</span>..<span class="number">11</span>], <span class="macro">vec!</span>[<span class="number">4</span>..<span class="number">6</span>], <span class="macro">vec!</span>[<span class="number">6</span>..<span class="number">8</span>], <span class="macro">vec!</span>[<span class="number">8</span>..<span class="number">9</span>]] |
| ); |
| } |
| |
| <span class="comment">// From <http://www.unicode.org/reports/tr9/#X10> |
| </span><span class="attribute">#[rustfmt::skip] |
| #[test] |
| </span><span class="kw">fn </span>test_isolating_run_sequences_sos_and_eos() { |
| |
| <span class="comment">// == Example 1 == |
| // text1·RLE·text2·LRE·text3·PDF·text4·PDF·RLE·text5·PDF·text6 |
| // index 0 1 2 3 4 5 6 7 8 9 10 11 |
| </span><span class="kw">let </span>classes = <span class="kw-2">&</span>[L, RLE, L, LRE, L, PDF, L, PDF, RLE, L, PDF, L]; |
| <span class="kw">let </span>levels = <span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">2</span>, <span class="number">2</span>, <span class="number">2</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">0</span>]; |
| <span class="kw">let </span>para_level = Level::ltr(); |
| <span class="kw">let </span><span class="kw-2">mut </span>sequences = isolating_run_sequences(para_level, classes, <span class="kw-2">&</span>Level::vec(levels)); |
| sequences.sort_by(|a, b| a.runs[<span class="number">0</span>].clone().cmp(b.runs[<span class="number">0</span>].clone())); |
| |
| <span class="comment">// text1 |
| </span><span class="macro">assert_eq!</span>( |
| <span class="kw-2">&</span>sequences[<span class="number">0</span>], |
| <span class="kw-2">&</span>IsolatingRunSequence { |
| runs: <span class="macro">vec!</span>[<span class="number">0</span>..<span class="number">2</span>], |
| sos: L, |
| eos: R, |
| } |
| ); |
| |
| <span class="comment">// text2 |
| </span><span class="macro">assert_eq!</span>( |
| <span class="kw-2">&</span>sequences[<span class="number">1</span>], |
| <span class="kw-2">&</span>IsolatingRunSequence { |
| runs: <span class="macro">vec!</span>[<span class="number">2</span>..<span class="number">4</span>], |
| sos: R, |
| eos: L, |
| } |
| ); |
| |
| <span class="comment">// text3 |
| </span><span class="macro">assert_eq!</span>( |
| <span class="kw-2">&</span>sequences[<span class="number">2</span>], |
| <span class="kw-2">&</span>IsolatingRunSequence { |
| runs: <span class="macro">vec!</span>[<span class="number">4</span>..<span class="number">6</span>], |
| sos: L, |
| eos: L, |
| } |
| ); |
| |
| <span class="comment">// text4 text5 |
| </span><span class="macro">assert_eq!</span>( |
| <span class="kw-2">&</span>sequences[<span class="number">3</span>], |
| <span class="kw-2">&</span>IsolatingRunSequence { |
| runs: <span class="macro">vec!</span>[<span class="number">6</span>..<span class="number">11</span>], |
| sos: L, |
| eos: R, |
| } |
| ); |
| |
| <span class="comment">// text6 |
| </span><span class="macro">assert_eq!</span>( |
| <span class="kw-2">&</span>sequences[<span class="number">4</span>], |
| <span class="kw-2">&</span>IsolatingRunSequence { |
| runs: <span class="macro">vec!</span>[<span class="number">11</span>..<span class="number">12</span>], |
| sos: R, |
| eos: L, |
| } |
| ); |
| |
| <span class="comment">// == Example 2 == |
| // text1·RLI·text2·LRI·text3·PDI·text4·PDI·RLI·text5·PDI·text6 |
| // index 0 1 2 3 4 5 6 7 8 9 10 11 |
| </span><span class="kw">let </span>classes = <span class="kw-2">&</span>[L, RLI, L, LRI, L, PDI, L, PDI, RLI, L, PDI, L]; |
| <span class="kw">let </span>levels = <span class="kw-2">&</span>[<span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">2</span>, <span class="number">1</span>, <span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>]; |
| <span class="kw">let </span>para_level = Level::ltr(); |
| <span class="kw">let </span><span class="kw-2">mut </span>sequences = isolating_run_sequences(para_level, classes, <span class="kw-2">&</span>Level::vec(levels)); |
| sequences.sort_by(|a, b| a.runs[<span class="number">0</span>].clone().cmp(b.runs[<span class="number">0</span>].clone())); |
| |
| <span class="comment">// text1·RLI·PDI·RLI·PDI·text6 |
| </span><span class="macro">assert_eq!</span>( |
| <span class="kw-2">&</span>sequences[<span class="number">0</span>], |
| <span class="kw-2">&</span>IsolatingRunSequence { |
| runs: <span class="macro">vec!</span>[<span class="number">0</span>..<span class="number">2</span>, <span class="number">7</span>..<span class="number">9</span>, <span class="number">10</span>..<span class="number">12</span>], |
| sos: L, |
| eos: L, |
| } |
| ); |
| |
| <span class="comment">// text2·LRI·PDI·text4 |
| </span><span class="macro">assert_eq!</span>( |
| <span class="kw-2">&</span>sequences[<span class="number">1</span>], |
| <span class="kw-2">&</span>IsolatingRunSequence { |
| runs: <span class="macro">vec!</span>[<span class="number">2</span>..<span class="number">4</span>, <span class="number">5</span>..<span class="number">7</span>], |
| sos: R, |
| eos: R, |
| } |
| ); |
| |
| <span class="comment">// text3 |
| </span><span class="macro">assert_eq!</span>( |
| <span class="kw-2">&</span>sequences[<span class="number">2</span>], |
| <span class="kw-2">&</span>IsolatingRunSequence { |
| runs: <span class="macro">vec!</span>[<span class="number">4</span>..<span class="number">5</span>], |
| sos: L, |
| eos: L, |
| } |
| ); |
| |
| <span class="comment">// text5 |
| </span><span class="macro">assert_eq!</span>( |
| <span class="kw-2">&</span>sequences[<span class="number">3</span>], |
| <span class="kw-2">&</span>IsolatingRunSequence { |
| runs: <span class="macro">vec!</span>[<span class="number">9</span>..<span class="number">10</span>], |
| sos: R, |
| eos: R, |
| } |
| ); |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_removed_by_x9() { |
| <span class="kw">let </span>rem_classes = <span class="kw-2">&</span>[RLE, LRE, RLO, LRO, PDF, BN]; |
| <span class="kw">let </span>not_classes = <span class="kw-2">&</span>[L, RLI, AL, LRI, PDI]; |
| <span class="kw">for </span>x <span class="kw">in </span>rem_classes { |
| <span class="macro">assert_eq!</span>(removed_by_x9(<span class="kw-2">*</span>x), <span class="bool-val">true</span>); |
| } |
| <span class="kw">for </span>x <span class="kw">in </span>not_classes { |
| <span class="macro">assert_eq!</span>(removed_by_x9(<span class="kw-2">*</span>x), <span class="bool-val">false</span>); |
| } |
| } |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_not_removed_by_x9() { |
| <span class="kw">let </span>non_x9_classes = <span class="kw-2">&</span>[L, R, AL, EN, ES, ET, AN, CS, NSM, B, S, WS, ON, LRI, RLI, FSI, PDI]; |
| <span class="kw">for </span>x <span class="kw">in </span>non_x9_classes { |
| <span class="macro">assert_eq!</span>(not_removed_by_x9(<span class="kw-2">&</span>x), <span class="bool-val">true</span>); |
| } |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="unicode_bidi" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
