| // 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. |
| |
| //! This crate implements the [Unicode Bidirectional Algorithm][tr9] for display of mixed |
| //! right-to-left and left-to-right text. It is written in safe Rust, compatible with the |
| //! current stable release. |
| //! |
| //! ## Example |
| //! |
| //! ```rust |
| //! # #[cfg(feature = "hardcoded-data")] { |
| //! use unicode_bidi::BidiInfo; |
| //! |
| //! // This example text is defined using `concat!` because some browsers |
| //! // and text editors have trouble displaying bidi strings. |
| //! let text = concat![ |
| //! "א", |
| //! "ב", |
| //! "ג", |
| //! "a", |
| //! "b", |
| //! "c", |
| //! ]; |
| //! |
| //! // Resolve embedding levels within the text. Pass `None` to detect the |
| //! // paragraph level automatically. |
| //! let bidi_info = BidiInfo::new(&text, None); |
| //! |
| //! // This paragraph has embedding level 1 because its first strong character is RTL. |
| //! assert_eq!(bidi_info.paragraphs.len(), 1); |
| //! let para = &bidi_info.paragraphs[0]; |
| //! assert_eq!(para.level.number(), 1); |
| //! assert_eq!(para.level.is_rtl(), true); |
| //! |
| //! // Re-ordering is done after wrapping each paragraph into a sequence of |
| //! // lines. For this example, I'll just use a single line that spans the |
| //! // entire paragraph. |
| //! let line = para.range.clone(); |
| //! |
| //! let display = bidi_info.reorder_line(para, line); |
| //! assert_eq!(display, concat![ |
| //! "a", |
| //! "b", |
| //! "c", |
| //! "ג", |
| //! "ב", |
| //! "א", |
| //! ]); |
| //! # } // feature = "hardcoded-data" |
| //! ``` |
| //! |
| //! # Features |
| //! |
| //! - `std`: Enabled by default, but can be disabled to make `unicode_bidi` |
| //! `#![no_std]` + `alloc` compatible. |
| //! - `hardcoded-data`: Enabled by default. Includes hardcoded Unicode bidi data and more convenient APIs. |
| //! - `serde`: Adds [`serde::Serialize`] and [`serde::Deserialize`] |
| //! implementations to relevant types. |
| //! |
| //! [tr9]: <http://www.unicode.org/reports/tr9/> |
| |
| #![no_std] |
| // We need to link to std to make doc tests work on older Rust versions |
| #[cfg(feature = "std")] |
| extern crate std; |
| #[macro_use] |
| extern crate alloc; |
| |
| pub mod data_source; |
| pub mod deprecated; |
| pub mod format_chars; |
| pub mod level; |
| |
| mod char_data; |
| mod explicit; |
| mod implicit; |
| mod prepare; |
| |
| pub use crate::char_data::{BidiClass, UNICODE_VERSION}; |
| pub use crate::data_source::BidiDataSource; |
| pub use crate::level::{Level, LTR_LEVEL, RTL_LEVEL}; |
| pub use crate::prepare::LevelRun; |
| |
| #[cfg(feature = "hardcoded-data")] |
| pub use crate::char_data::{bidi_class, HardcodedBidiData}; |
| |
| use alloc::borrow::Cow; |
| use alloc::string::String; |
| use alloc::vec::Vec; |
| use core::cmp; |
| use core::iter::repeat; |
| use core::ops::Range; |
| |
| use crate::format_chars as chars; |
| use crate::BidiClass::*; |
| |
| #[derive(PartialEq, Debug)] |
| pub enum Direction { |
| Ltr, |
| Rtl, |
| Mixed, |
| } |
| |
| /// Bidi information about a single paragraph |
| #[derive(Debug, PartialEq)] |
| pub struct ParagraphInfo { |
| /// The paragraphs boundaries within the text, as byte indices. |
| /// |
| /// TODO: Shrink this to only include the starting index? |
| pub range: Range<usize>, |
| |
| /// The paragraph embedding level. |
| /// |
| /// <http://www.unicode.org/reports/tr9/#BD4> |
| pub level: Level, |
| } |
| |
| impl ParagraphInfo { |
| /// Gets the length of the paragraph in the source text. |
| pub fn len(&self) -> usize { |
| self.range.end - self.range.start |
| } |
| } |
| |
| /// Initial bidi information of the text. |
| /// |
| /// Contains the text paragraphs and `BidiClass` of its characters. |
| #[derive(PartialEq, Debug)] |
| pub struct InitialInfo<'text> { |
| /// The text |
| pub text: &'text str, |
| |
| /// The BidiClass of the character at each byte in the text. |
| /// If a character is multiple bytes, its class will appear multiple times in the vector. |
| pub original_classes: Vec<BidiClass>, |
| |
| /// The boundaries and level of each paragraph within the text. |
| pub paragraphs: Vec<ParagraphInfo>, |
| } |
| |
| impl<'text> InitialInfo<'text> { |
| /// Find the paragraphs and BidiClasses in a string of text. |
| /// |
| /// <http://www.unicode.org/reports/tr9/#The_Paragraph_Level> |
| /// |
| /// Also sets the class for each First Strong Isolate initiator (FSI) to LRI or RLI if a strong |
| /// character is found before the matching PDI. If no strong character is found, the class will |
| /// remain FSI, and it's up to later stages to treat these as LRI when needed. |
| /// |
| /// The `hardcoded-data` Cargo feature (enabled by default) must be enabled to use this. |
| #[cfg_attr(feature = "flame_it", flamer::flame)] |
| #[cfg(feature = "hardcoded-data")] |
| pub fn new(text: &str, default_para_level: Option<Level>) -> InitialInfo<'_> { |
| Self::new_with_data_source(&HardcodedBidiData, text, default_para_level) |
| } |
| |
| /// Find the paragraphs and BidiClasses in a string of text, with a custom [`BidiDataSource`] |
| /// for Bidi data. If you just wish to use the hardcoded Bidi data, please use [`InitialInfo::new()`] |
| /// instead (enabled with tbe default `hardcoded-data` Cargo feature) |
| /// |
| /// <http://www.unicode.org/reports/tr9/#The_Paragraph_Level> |
| /// |
| /// Also sets the class for each First Strong Isolate initiator (FSI) to LRI or RLI if a strong |
| /// character is found before the matching PDI. If no strong character is found, the class will |
| /// remain FSI, and it's up to later stages to treat these as LRI when needed. |
| #[cfg_attr(feature = "flame_it", flamer::flame)] |
| pub fn new_with_data_source<'a, D: BidiDataSource>( |
| data_source: &D, |
| text: &'a str, |
| default_para_level: Option<Level>, |
| ) -> InitialInfo<'a> { |
| let mut original_classes = Vec::with_capacity(text.len()); |
| |
| // The stack contains the starting byte index for each nested isolate we're inside. |
| let mut isolate_stack = Vec::new(); |
| let mut paragraphs = Vec::new(); |
| |
| let mut para_start = 0; |
| let mut para_level = default_para_level; |
| |
| #[cfg(feature = "flame_it")] |
| flame::start("InitialInfo::new(): iter text.char_indices()"); |
| |
| for (i, c) in text.char_indices() { |
| let class = data_source.bidi_class(c); |
| |
| #[cfg(feature = "flame_it")] |
| flame::start("original_classes.extend()"); |
| |
| original_classes.extend(repeat(class).take(c.len_utf8())); |
| |
| #[cfg(feature = "flame_it")] |
| flame::end("original_classes.extend()"); |
| |
| match class { |
| B => { |
| // P1. Split the text into separate paragraphs. The paragraph separator is kept |
| // with the previous paragraph. |
| let para_end = i + c.len_utf8(); |
| paragraphs.push(ParagraphInfo { |
| range: para_start..para_end, |
| // P3. If no character is found in p2, set the paragraph level to zero. |
| level: para_level.unwrap_or(LTR_LEVEL), |
| }); |
| // Reset state for the start of the next paragraph. |
| para_start = para_end; |
| // TODO: Support defaulting to direction of previous paragraph |
| // |
| // <http://www.unicode.org/reports/tr9/#HL1> |
| para_level = default_para_level; |
| isolate_stack.clear(); |
| } |
| |
| L | R | AL => { |
| match isolate_stack.last() { |
| Some(&start) => { |
| if original_classes[start] == FSI { |
| // X5c. If the first strong character between FSI and its matching |
| // PDI is R or AL, treat it as RLI. Otherwise, treat it as LRI. |
| for j in 0..chars::FSI.len_utf8() { |
| original_classes[start + j] = |
| if class == L { LRI } else { RLI }; |
| } |
| } |
| } |
| |
| None => { |
| if para_level.is_none() { |
| // P2. Find the first character of type L, AL, or R, while skipping |
| // any characters between an isolate initiator and its matching |
| // PDI. |
| para_level = Some(if class != L { RTL_LEVEL } else { LTR_LEVEL }); |
| } |
| } |
| } |
| } |
| |
| RLI | LRI | FSI => { |
| isolate_stack.push(i); |
| } |
| |
| PDI => { |
| isolate_stack.pop(); |
| } |
| |
| _ => {} |
| } |
| } |
| if para_start < text.len() { |
| paragraphs.push(ParagraphInfo { |
| range: para_start..text.len(), |
| level: para_level.unwrap_or(LTR_LEVEL), |
| }); |
| } |
| assert_eq!(original_classes.len(), text.len()); |
| |
| #[cfg(feature = "flame_it")] |
| flame::end("InitialInfo::new(): iter text.char_indices()"); |
| |
| InitialInfo { |
| text, |
| original_classes, |
| paragraphs, |
| } |
| } |
| } |
| |
| /// Bidi information of the text. |
| /// |
| /// The `original_classes` and `levels` vectors are indexed by byte offsets into the text. If a |
| /// character is multiple bytes wide, then its class and level will appear multiple times in these |
| /// vectors. |
| // TODO: Impl `struct StringProperty<T> { values: Vec<T> }` and use instead of Vec<T> |
| #[derive(Debug, PartialEq)] |
| pub struct BidiInfo<'text> { |
| /// The text |
| pub text: &'text str, |
| |
| /// The BidiClass of the character at each byte in the text. |
| pub original_classes: Vec<BidiClass>, |
| |
| /// The directional embedding level of each byte in the text. |
| pub levels: Vec<Level>, |
| |
| /// The boundaries and paragraph embedding level of each paragraph within the text. |
| /// |
| /// TODO: Use SmallVec or similar to avoid overhead when there are only one or two paragraphs? |
| /// Or just don't include the first paragraph, which always starts at 0? |
| pub paragraphs: Vec<ParagraphInfo>, |
| } |
| |
| impl<'text> BidiInfo<'text> { |
| /// Split the text into paragraphs and determine the bidi embedding levels for each paragraph. |
| /// |
| /// |
| /// The `hardcoded-data` Cargo feature (enabled by default) must be enabled to use this. |
| /// |
| /// TODO: In early steps, check for special cases that allow later steps to be skipped. like |
| /// text that is entirely LTR. See the `nsBidi` class from Gecko for comparison. |
| /// |
| /// TODO: Support auto-RTL base direction |
| #[cfg_attr(feature = "flame_it", flamer::flame)] |
| #[cfg(feature = "hardcoded-data")] |
| pub fn new(text: &str, default_para_level: Option<Level>) -> BidiInfo<'_> { |
| Self::new_with_data_source(&HardcodedBidiData, text, default_para_level) |
| } |
| |
| /// Split the text into paragraphs and determine the bidi embedding levels for each paragraph, with a custom [`BidiDataSource`] |
| /// for Bidi data. If you just wish to use the hardcoded Bidi data, please use [`BidiInfo::new()`] |
| /// instead (enabled with tbe default `hardcoded-data` Cargo feature). |
| /// |
| /// TODO: In early steps, check for special cases that allow later steps to be skipped. like |
| /// text that is entirely LTR. See the `nsBidi` class from Gecko for comparison. |
| /// |
| /// TODO: Support auto-RTL base direction |
| #[cfg_attr(feature = "flame_it", flamer::flame)] |
| pub fn new_with_data_source<'a, D: BidiDataSource>( |
| data_source: &D, |
| text: &'a str, |
| default_para_level: Option<Level>, |
| ) -> BidiInfo<'a> { |
| let InitialInfo { |
| original_classes, |
| paragraphs, |
| .. |
| } = InitialInfo::new_with_data_source(data_source, text, default_para_level); |
| |
| let mut levels = Vec::<Level>::with_capacity(text.len()); |
| let mut processing_classes = original_classes.clone(); |
| |
| for para in ¶graphs { |
| let text = &text[para.range.clone()]; |
| let original_classes = &original_classes[para.range.clone()]; |
| let processing_classes = &mut processing_classes[para.range.clone()]; |
| |
| let new_len = levels.len() + para.range.len(); |
| levels.resize(new_len, para.level); |
| let levels = &mut levels[para.range.clone()]; |
| |
| explicit::compute( |
| text, |
| para.level, |
| original_classes, |
| levels, |
| processing_classes, |
| ); |
| |
| let sequences = prepare::isolating_run_sequences(para.level, original_classes, levels); |
| for sequence in &sequences { |
| implicit::resolve_weak(text, sequence, processing_classes); |
| implicit::resolve_neutral( |
| text, |
| data_source, |
| sequence, |
| levels, |
| original_classes, |
| processing_classes, |
| ); |
| } |
| implicit::resolve_levels(processing_classes, levels); |
| |
| assign_levels_to_removed_chars(para.level, original_classes, levels); |
| } |
| |
| BidiInfo { |
| text, |
| original_classes, |
| paragraphs, |
| levels, |
| } |
| } |
| |
| /// Re-order a line based on resolved levels and return only the embedding levels, one `Level` |
| /// per *byte*. |
| #[cfg_attr(feature = "flame_it", flamer::flame)] |
| pub fn reordered_levels(&self, para: &ParagraphInfo, line: Range<usize>) -> Vec<Level> { |
| let (levels, _) = self.visual_runs(para, line); |
| levels |
| } |
| |
| /// Re-order a line based on resolved levels and return only the embedding levels, one `Level` |
| /// per *character*. |
| #[cfg_attr(feature = "flame_it", flamer::flame)] |
| pub fn reordered_levels_per_char( |
| &self, |
| para: &ParagraphInfo, |
| line: Range<usize>, |
| ) -> Vec<Level> { |
| let levels = self.reordered_levels(para, line); |
| self.text.char_indices().map(|(i, _)| levels[i]).collect() |
| } |
| |
| /// Re-order a line based on resolved levels and return the line in display order. |
| #[cfg_attr(feature = "flame_it", flamer::flame)] |
| pub fn reorder_line(&self, para: &ParagraphInfo, line: Range<usize>) -> Cow<'text, str> { |
| let (levels, runs) = self.visual_runs(para, line.clone()); |
| |
| // If all isolating run sequences are LTR, no reordering is needed |
| if runs.iter().all(|run| levels[run.start].is_ltr()) { |
| return self.text[line].into(); |
| } |
| |
| let mut result = String::with_capacity(line.len()); |
| for run in runs { |
| if levels[run.start].is_rtl() { |
| result.extend(self.text[run].chars().rev()); |
| } else { |
| result.push_str(&self.text[run]); |
| } |
| } |
| result.into() |
| } |
| |
| /// Reorders pre-calculated levels of a sequence of characters. |
| /// |
| /// NOTE: This is a convenience method that does not use a `Paragraph` object. It is |
| /// intended to be used when an application has determined the levels of the objects (character sequences) |
| /// and just needs to have them reordered. |
| /// |
| /// the index map will result in `indexMap[visualIndex]==logicalIndex`. |
| /// |
| /// This only runs [Rule L2](http://www.unicode.org/reports/tr9/#L2) as it does not have |
| /// information about the actual text. |
| /// |
| /// Furthermore, if `levels` is an array that is aligned with code units, bytes within a codepoint may be |
| /// reversed. You may need to fix up the map to deal with this. Alternatively, only pass in arrays where each `Level` |
| /// is for a single code point. |
| /// |
| /// |
| /// # # Example |
| /// ``` |
| /// use unicode_bidi::BidiInfo; |
| /// use unicode_bidi::Level; |
| /// |
| /// let l0 = Level::from(0); |
| /// let l1 = Level::from(1); |
| /// let l2 = Level::from(2); |
| /// |
| /// let levels = vec![l0, l0, l0, l0]; |
| /// let index_map = BidiInfo::reorder_visual(&levels); |
| /// assert_eq!(levels.len(), index_map.len()); |
| /// assert_eq!(index_map, [0, 1, 2, 3]); |
| /// |
| /// let levels: Vec<Level> = vec![l0, l0, l0, l1, l1, l1, l2, l2]; |
| /// let index_map = BidiInfo::reorder_visual(&levels); |
| /// assert_eq!(levels.len(), index_map.len()); |
| /// assert_eq!(index_map, [0, 1, 2, 6, 7, 5, 4, 3]); |
| /// ``` |
| pub fn reorder_visual(levels: &[Level]) -> Vec<usize> { |
| // Gets the next range of characters after start_index with a level greater |
| // than or equal to `max` |
| fn next_range(levels: &[level::Level], mut start_index: usize, max: Level) -> Range<usize> { |
| if levels.is_empty() || start_index >= levels.len() { |
| return start_index..start_index; |
| } |
| while let Some(l) = levels.get(start_index) { |
| if *l >= max { |
| break; |
| } |
| start_index += 1; |
| } |
| |
| if levels.get(start_index).is_none() { |
| // If at the end of the array, adding one will |
| // produce an out-of-range end element |
| return start_index..start_index; |
| } |
| |
| let mut end_index = start_index + 1; |
| while let Some(l) = levels.get(end_index) { |
| if *l < max { |
| return start_index..end_index; |
| } |
| end_index += 1; |
| } |
| |
| start_index..end_index |
| } |
| |
| // This implementation is similar to the L2 implementation in `visual_runs()` |
| // but it cannot benefit from a precalculated LevelRun vector so needs to be different. |
| |
| if levels.is_empty() { |
| return vec![]; |
| } |
| |
| // Get the min and max levels |
| let (mut min, mut max) = levels |
| .iter() |
| .fold((levels[0], levels[0]), |(min, max), &l| { |
| (cmp::min(min, l), cmp::max(max, l)) |
| }); |
| |
| // Initialize an index map |
| let mut result: Vec<usize> = (0..levels.len()).collect(); |
| |
| if min == max && min.is_ltr() { |
| // Everything is LTR and at the same level, do nothing |
| return result; |
| } |
| |
| // Stop at the lowest *odd* level, since everything below that |
| // is LTR and does not need further reordering |
| min = min.new_lowest_ge_rtl().expect("Level error"); |
| |
| // For each max level, take all contiguous chunks of |
| // levels ≥ max and reverse them |
| // |
| // We can do this check with the original levels instead of checking reorderings because all |
| // prior reorderings will have been for contiguous chunks of levels >> max, which will |
| // be a subset of these chunks anyway. |
| while min <= max { |
| let mut range = 0..0; |
| loop { |
| range = next_range(levels, range.end, max); |
| result[range.clone()].reverse(); |
| |
| if range.end >= levels.len() { |
| break; |
| } |
| } |
| |
| max.lower(1).expect("Level error"); |
| } |
| |
| result |
| } |
| |
| /// Find the level runs within a line and return them in visual order. |
| /// |
| /// `line` is a range of bytes indices within `levels`. |
| /// |
| /// <http://www.unicode.org/reports/tr9/#Reordering_Resolved_Levels> |
| #[cfg_attr(feature = "flame_it", flamer::flame)] |
| pub fn visual_runs( |
| &self, |
| para: &ParagraphInfo, |
| line: Range<usize>, |
| ) -> (Vec<Level>, Vec<LevelRun>) { |
| assert!(line.start <= self.levels.len()); |
| assert!(line.end <= self.levels.len()); |
| |
| let mut levels = self.levels.clone(); |
| let line_classes = &self.original_classes[line.clone()]; |
| let line_levels = &mut levels[line.clone()]; |
| |
| // Reset some whitespace chars to paragraph level. |
| // <http://www.unicode.org/reports/tr9/#L1> |
| let line_str: &str = &self.text[line.clone()]; |
| let mut reset_from: Option<usize> = Some(0); |
| let mut reset_to: Option<usize> = None; |
| let mut prev_level = para.level; |
| for (i, c) in line_str.char_indices() { |
| match line_classes[i] { |
| // Segment separator, Paragraph separator |
| B | S => { |
| assert_eq!(reset_to, None); |
| reset_to = Some(i + c.len_utf8()); |
| if reset_from == None { |
| reset_from = Some(i); |
| } |
| } |
| // Whitespace, isolate formatting |
| WS | FSI | LRI | RLI | PDI => { |
| if reset_from == None { |
| reset_from = Some(i); |
| } |
| } |
| // <https://www.unicode.org/reports/tr9/#Retaining_Explicit_Formatting_Characters> |
| // same as above + set the level |
| RLE | LRE | RLO | LRO | PDF | BN => { |
| if reset_from == None { |
| reset_from = Some(i); |
| } |
| // also set the level to previous |
| line_levels[i] = prev_level; |
| } |
| _ => { |
| reset_from = None; |
| } |
| } |
| if let (Some(from), Some(to)) = (reset_from, reset_to) { |
| for level in &mut line_levels[from..to] { |
| *level = para.level; |
| } |
| reset_from = None; |
| reset_to = None; |
| } |
| prev_level = line_levels[i]; |
| } |
| if let Some(from) = reset_from { |
| for level in &mut line_levels[from..] { |
| *level = para.level; |
| } |
| } |
| |
| // Find consecutive level runs. |
| let mut runs = Vec::new(); |
| let mut start = line.start; |
| let mut run_level = levels[start]; |
| let mut min_level = run_level; |
| let mut max_level = run_level; |
| |
| for (i, &new_level) in levels.iter().enumerate().take(line.end).skip(start + 1) { |
| if new_level != run_level { |
| // End of the previous run, start of a new one. |
| runs.push(start..i); |
| start = i; |
| run_level = new_level; |
| min_level = cmp::min(run_level, min_level); |
| max_level = cmp::max(run_level, max_level); |
| } |
| } |
| runs.push(start..line.end); |
| |
| let run_count = runs.len(); |
| |
| // Re-order the odd runs. |
| // <http://www.unicode.org/reports/tr9/#L2> |
| |
| // Stop at the lowest *odd* level. |
| min_level = min_level.new_lowest_ge_rtl().expect("Level error"); |
| |
| // This loop goes through contiguous chunks of level runs that have a level |
| // ≥ max_level and reverses their contents, reducing max_level by 1 each time. |
| // |
| // It can do this check with the original levels instead of checking reorderings because all |
| // prior reorderings will have been for contiguous chunks of levels >> max, which will |
| // be a subset of these chunks anyway. |
| while max_level >= min_level { |
| // Look for the start of a sequence of consecutive runs of max_level or higher. |
| let mut seq_start = 0; |
| while seq_start < run_count { |
| if self.levels[runs[seq_start].start] < max_level { |
| seq_start += 1; |
| continue; |
| } |
| |
| // Found the start of a sequence. Now find the end. |
| let mut seq_end = seq_start + 1; |
| while seq_end < run_count { |
| if self.levels[runs[seq_end].start] < max_level { |
| break; |
| } |
| seq_end += 1; |
| } |
| |
| // Reverse the runs within this sequence. |
| runs[seq_start..seq_end].reverse(); |
| |
| seq_start = seq_end; |
| } |
| max_level |
| .lower(1) |
| .expect("Lowering embedding level below zero"); |
| } |
| |
| (levels, runs) |
| } |
| |
| /// If processed text has any computed RTL levels |
| /// |
| /// This information is usually used to skip re-ordering of text when no RTL level is present |
| #[inline] |
| pub fn has_rtl(&self) -> bool { |
| level::has_rtl(&self.levels) |
| } |
| } |
| |
| /// Contains a reference of `BidiInfo` and one of its `paragraphs`. |
| /// And it supports all operation in the `Paragraph` that needs also its |
| /// `BidiInfo` such as `direction`. |
| #[derive(Debug)] |
| pub struct Paragraph<'a, 'text> { |
| pub info: &'a BidiInfo<'text>, |
| pub para: &'a ParagraphInfo, |
| } |
| |
| impl<'a, 'text> Paragraph<'a, 'text> { |
| pub fn new(info: &'a BidiInfo<'text>, para: &'a ParagraphInfo) -> Paragraph<'a, 'text> { |
| Paragraph { info, para } |
| } |
| |
| /// Returns if the paragraph is Left direction, right direction or mixed. |
| pub fn direction(&self) -> Direction { |
| let mut ltr = false; |
| let mut rtl = false; |
| for i in self.para.range.clone() { |
| if self.info.levels[i].is_ltr() { |
| ltr = true; |
| } |
| |
| if self.info.levels[i].is_rtl() { |
| rtl = true; |
| } |
| } |
| |
| if ltr && rtl { |
| return Direction::Mixed; |
| } |
| |
| if ltr { |
| return Direction::Ltr; |
| } |
| |
| Direction::Rtl |
| } |
| |
| /// Returns the `Level` of a certain character in the paragraph. |
| pub fn level_at(&self, pos: usize) -> Level { |
| let actual_position = self.para.range.start + pos; |
| self.info.levels[actual_position] |
| } |
| } |
| |
| /// Assign levels to characters removed by rule X9. |
| /// |
| /// The levels assigned to these characters are not specified by the algorithm. This function |
| /// assigns each one the level of the previous character, to avoid breaking level runs. |
| #[cfg_attr(feature = "flame_it", flamer::flame)] |
| fn assign_levels_to_removed_chars(para_level: Level, classes: &[BidiClass], levels: &mut [Level]) { |
| for i in 0..levels.len() { |
| if prepare::removed_by_x9(classes[i]) { |
| levels[i] = if i > 0 { levels[i - 1] } else { para_level }; |
| } |
| } |
| } |
| |
| #[cfg(test)] |
| #[cfg(feature = "hardcoded-data")] |
| mod tests { |
| use super::*; |
| |
| #[test] |
| fn test_initial_text_info() { |
| let text = "a1"; |
| assert_eq!( |
| InitialInfo::new(text, None), |
| InitialInfo { |
| text, |
| original_classes: vec![L, EN], |
| paragraphs: vec![ParagraphInfo { |
| range: 0..2, |
| level: LTR_LEVEL, |
| },], |
| } |
| ); |
| |
| let text = "غ א"; |
| assert_eq!( |
| InitialInfo::new(text, None), |
| InitialInfo { |
| text, |
| original_classes: vec![AL, AL, WS, R, R], |
| paragraphs: vec![ParagraphInfo { |
| range: 0..5, |
| level: RTL_LEVEL, |
| },], |
| } |
| ); |
| |
| let text = "a\u{2029}b"; |
| assert_eq!( |
| InitialInfo::new(text, None), |
| InitialInfo { |
| text, |
| original_classes: vec![L, B, B, B, L], |
| paragraphs: vec![ |
| ParagraphInfo { |
| range: 0..4, |
| level: LTR_LEVEL, |
| }, |
| ParagraphInfo { |
| range: 4..5, |
| level: LTR_LEVEL, |
| }, |
| ], |
| } |
| ); |
| |
| let text = format!("{}א{}a", chars::FSI, chars::PDI); |
| assert_eq!( |
| InitialInfo::new(&text, None), |
| InitialInfo { |
| text: &text, |
| original_classes: vec![RLI, RLI, RLI, R, R, PDI, PDI, PDI, L], |
| paragraphs: vec![ParagraphInfo { |
| range: 0..9, |
| level: LTR_LEVEL, |
| },], |
| } |
| ); |
| } |
| |
| #[test] |
| #[cfg(feature = "hardcoded-data")] |
| fn test_process_text() { |
| let text = "abc123"; |
| assert_eq!( |
| BidiInfo::new(text, Some(LTR_LEVEL)), |
| BidiInfo { |
| text, |
| levels: Level::vec(&[0, 0, 0, 0, 0, 0]), |
| original_classes: vec![L, L, L, EN, EN, EN], |
| paragraphs: vec![ParagraphInfo { |
| range: 0..6, |
| level: LTR_LEVEL, |
| },], |
| } |
| ); |
| |
| let text = "abc אבג"; |
| assert_eq!( |
| BidiInfo::new(text, Some(LTR_LEVEL)), |
| BidiInfo { |
| text, |
| levels: Level::vec(&[0, 0, 0, 0, 1, 1, 1, 1, 1, 1]), |
| original_classes: vec![L, L, L, WS, R, R, R, R, R, R], |
| paragraphs: vec![ParagraphInfo { |
| range: 0..10, |
| level: LTR_LEVEL, |
| },], |
| } |
| ); |
| assert_eq!( |
| BidiInfo::new(text, Some(RTL_LEVEL)), |
| BidiInfo { |
| text, |
| levels: Level::vec(&[2, 2, 2, 1, 1, 1, 1, 1, 1, 1]), |
| original_classes: vec![L, L, L, WS, R, R, R, R, R, R], |
| paragraphs: vec![ParagraphInfo { |
| range: 0..10, |
| level: RTL_LEVEL, |
| },], |
| } |
| ); |
| |
| let text = "אבג abc"; |
| assert_eq!( |
| BidiInfo::new(text, Some(LTR_LEVEL)), |
| BidiInfo { |
| text, |
| levels: Level::vec(&[1, 1, 1, 1, 1, 1, 0, 0, 0, 0]), |
| original_classes: vec![R, R, R, R, R, R, WS, L, L, L], |
| paragraphs: vec![ParagraphInfo { |
| range: 0..10, |
| level: LTR_LEVEL, |
| },], |
| } |
| ); |
| assert_eq!( |
| BidiInfo::new(text, None), |
| BidiInfo { |
| text, |
| levels: Level::vec(&[1, 1, 1, 1, 1, 1, 1, 2, 2, 2]), |
| original_classes: vec![R, R, R, R, R, R, WS, L, L, L], |
| paragraphs: vec![ParagraphInfo { |
| range: 0..10, |
| level: RTL_LEVEL, |
| },], |
| } |
| ); |
| |
| let text = "غ2ظ א2ג"; |
| assert_eq!( |
| BidiInfo::new(text, Some(LTR_LEVEL)), |
| BidiInfo { |
| text, |
| levels: Level::vec(&[1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1]), |
| original_classes: vec![AL, AL, EN, AL, AL, WS, R, R, EN, R, R], |
| paragraphs: vec![ParagraphInfo { |
| range: 0..11, |
| level: LTR_LEVEL, |
| },], |
| } |
| ); |
| |
| let text = "a א.\nג"; |
| assert_eq!( |
| BidiInfo::new(text, None), |
| BidiInfo { |
| text, |
| original_classes: vec![L, WS, R, R, CS, B, R, R], |
| levels: Level::vec(&[0, 0, 1, 1, 0, 0, 1, 1]), |
| paragraphs: vec![ |
| ParagraphInfo { |
| range: 0..6, |
| level: LTR_LEVEL, |
| }, |
| ParagraphInfo { |
| range: 6..8, |
| level: RTL_LEVEL, |
| }, |
| ], |
| } |
| ); |
| |
| // BidiTest:69635 (AL ET EN) |
| let bidi_info = BidiInfo::new("\u{060B}\u{20CF}\u{06F9}", None); |
| assert_eq!(bidi_info.original_classes, vec![AL, AL, ET, ET, ET, EN, EN]); |
| } |
| |
| #[test] |
| #[cfg(feature = "hardcoded-data")] |
| fn test_bidi_info_has_rtl() { |
| // ASCII only |
| assert_eq!(BidiInfo::new("123", None).has_rtl(), false); |
| assert_eq!(BidiInfo::new("123", Some(LTR_LEVEL)).has_rtl(), false); |
| assert_eq!(BidiInfo::new("123", Some(RTL_LEVEL)).has_rtl(), false); |
| assert_eq!(BidiInfo::new("abc", None).has_rtl(), false); |
| assert_eq!(BidiInfo::new("abc", Some(LTR_LEVEL)).has_rtl(), false); |
| assert_eq!(BidiInfo::new("abc", Some(RTL_LEVEL)).has_rtl(), false); |
| assert_eq!(BidiInfo::new("abc 123", None).has_rtl(), false); |
| assert_eq!(BidiInfo::new("abc\n123", None).has_rtl(), false); |
| |
| // With Hebrew |
| assert_eq!(BidiInfo::new("אבּג", None).has_rtl(), true); |
| assert_eq!(BidiInfo::new("אבּג", Some(LTR_LEVEL)).has_rtl(), true); |
| assert_eq!(BidiInfo::new("אבּג", Some(RTL_LEVEL)).has_rtl(), true); |
| assert_eq!(BidiInfo::new("abc אבּג", None).has_rtl(), true); |
| assert_eq!(BidiInfo::new("abc\nאבּג", None).has_rtl(), true); |
| assert_eq!(BidiInfo::new("אבּג abc", None).has_rtl(), true); |
| assert_eq!(BidiInfo::new("אבּג\nabc", None).has_rtl(), true); |
| assert_eq!(BidiInfo::new("אבּג 123", None).has_rtl(), true); |
| assert_eq!(BidiInfo::new("אבּג\n123", None).has_rtl(), true); |
| } |
| |
| #[cfg(feature = "hardcoded-data")] |
| fn reorder_paras(text: &str) -> Vec<Cow<'_, str>> { |
| let bidi_info = BidiInfo::new(text, None); |
| bidi_info |
| .paragraphs |
| .iter() |
| .map(|para| bidi_info.reorder_line(para, para.range.clone())) |
| .collect() |
| } |
| |
| #[test] |
| #[cfg(feature = "hardcoded-data")] |
| fn test_reorder_line() { |
| // Bidi_Class: L L L B L L L B L L L |
| assert_eq!( |
| reorder_paras("abc\ndef\nghi"), |
| vec!["abc\n", "def\n", "ghi"] |
| ); |
| |
| // Bidi_Class: L L EN B L L EN B L L EN |
| assert_eq!( |
| reorder_paras("ab1\nde2\ngh3"), |
| vec!["ab1\n", "de2\n", "gh3"] |
| ); |
| |
| // Bidi_Class: L L L B AL AL AL |
| assert_eq!(reorder_paras("abc\nابج"), vec!["abc\n", "جبا"]); |
| |
| // Bidi_Class: AL AL AL B L L L |
| assert_eq!(reorder_paras("ابج\nabc"), vec!["\nجبا", "abc"]); |
| |
| assert_eq!(reorder_paras("1.-2"), vec!["1.-2"]); |
| assert_eq!(reorder_paras("1-.2"), vec!["1-.2"]); |
| assert_eq!(reorder_paras("abc אבג"), vec!["abc גבא"]); |
| |
| // Numbers being weak LTR characters, cannot reorder strong RTL |
| assert_eq!(reorder_paras("123 אבג"), vec!["גבא 123"]); |
| |
| assert_eq!(reorder_paras("abc\u{202A}def"), vec!["abc\u{202A}def"]); |
| |
| assert_eq!( |
| reorder_paras("abc\u{202A}def\u{202C}ghi"), |
| vec!["abc\u{202A}def\u{202C}ghi"] |
| ); |
| |
| assert_eq!( |
| reorder_paras("abc\u{2066}def\u{2069}ghi"), |
| vec!["abc\u{2066}def\u{2069}ghi"] |
| ); |
| |
| // Testing for RLE Character |
| assert_eq!( |
| reorder_paras("\u{202B}abc אבג\u{202C}"), |
| vec!["\u{202B}\u{202C}גבא abc"] |
| ); |
| |
| // Testing neutral characters |
| assert_eq!(reorder_paras("אבג? אבג"), vec!["גבא ?גבא"]); |
| |
| // Testing neutral characters with special case |
| assert_eq!(reorder_paras("A אבג?"), vec!["A גבא?"]); |
| |
| // Testing neutral characters with Implicit RTL Marker |
| assert_eq!(reorder_paras("A אבג?\u{200F}"), vec!["A \u{200F}?גבא"]); |
| assert_eq!(reorder_paras("אבג abc"), vec!["abc גבא"]); |
| assert_eq!( |
| reorder_paras("abc\u{2067}.-\u{2069}ghi"), |
| vec!["abc\u{2067}-.\u{2069}ghi"] |
| ); |
| |
| assert_eq!( |
| reorder_paras("Hello, \u{2068}\u{202E}world\u{202C}\u{2069}!"), |
| vec!["Hello, \u{2068}\u{202E}\u{202C}dlrow\u{2069}!"] |
| ); |
| |
| // With mirrorable characters in RTL run |
| assert_eq!(reorder_paras("א(ב)ג."), vec![".ג)ב(א"]); |
| |
| // With mirrorable characters on level boundry |
| assert_eq!(reorder_paras("אב(גד[&ef].)gh"), vec!["gh).]ef&[דג(בא"]); |
| } |
| |
| fn reordered_levels_for_paras(text: &str) -> Vec<Vec<Level>> { |
| let bidi_info = BidiInfo::new(text, None); |
| bidi_info |
| .paragraphs |
| .iter() |
| .map(|para| bidi_info.reordered_levels(para, para.range.clone())) |
| .collect() |
| } |
| |
| fn reordered_levels_per_char_for_paras(text: &str) -> Vec<Vec<Level>> { |
| let bidi_info = BidiInfo::new(text, None); |
| bidi_info |
| .paragraphs |
| .iter() |
| .map(|para| bidi_info.reordered_levels_per_char(para, para.range.clone())) |
| .collect() |
| } |
| |
| #[test] |
| #[cfg(feature = "hardcoded-data")] |
| fn test_reordered_levels() { |
| // BidiTest:946 (LRI PDI) |
| let text = "\u{2067}\u{2069}"; |
| assert_eq!( |
| reordered_levels_for_paras(text), |
| vec![Level::vec(&[0, 0, 0, 0, 0, 0])] |
| ); |
| assert_eq!( |
| reordered_levels_per_char_for_paras(text), |
| vec![Level::vec(&[0, 0])] |
| ); |
| |
| let text = "aa טֶ"; |
| let bidi_info = BidiInfo::new(text, None); |
| assert_eq!( |
| bidi_info.reordered_levels(&bidi_info.paragraphs[0], 3..7), |
| Level::vec(&[0, 0, 0, 1, 1, 1, 1]), |
| ) |
| |
| /* TODO |
| /// BidiTest:69635 (AL ET EN) |
| let text = "\u{060B}\u{20CF}\u{06F9}"; |
| assert_eq!( |
| reordered_levels_for_paras(text), |
| vec![Level::vec(&[1, 1, 1, 1, 1, 2, 2])] |
| ); |
| assert_eq!( |
| reordered_levels_per_char_for_paras(text), |
| vec![Level::vec(&[1, 1, 2])] |
| ); |
| */ |
| |
| /* TODO |
| // BidiTest:291284 (AN RLI PDF R) |
| assert_eq!( |
| reordered_levels_per_char_for_paras("\u{0605}\u{2067}\u{202C}\u{0590}"), |
| vec![&["2", "0", "x", "1"]] |
| ); |
| */ |
| } |
| |
| #[test] |
| fn test_paragraph_info_len() { |
| let text = "hello world"; |
| let bidi_info = BidiInfo::new(text, None); |
| assert_eq!(bidi_info.paragraphs.len(), 1); |
| assert_eq!(bidi_info.paragraphs[0].len(), text.len()); |
| |
| let text2 = "How are you"; |
| let whole_text = format!("{}\n{}", text, text2); |
| let bidi_info = BidiInfo::new(&whole_text, None); |
| assert_eq!(bidi_info.paragraphs.len(), 2); |
| |
| // The first paragraph include the paragraph separator. |
| // TODO: investigate if the paragraph separator character |
| // should not be part of any paragraph. |
| assert_eq!(bidi_info.paragraphs[0].len(), text.len() + 1); |
| assert_eq!(bidi_info.paragraphs[1].len(), text2.len()); |
| } |
| |
| #[test] |
| fn test_direction() { |
| let ltr_text = "hello world"; |
| let rtl_text = "أهلا بكم"; |
| let all_paragraphs = format!("{}\n{}\n{}{}", ltr_text, rtl_text, ltr_text, rtl_text); |
| let bidi_info = BidiInfo::new(&all_paragraphs, None); |
| assert_eq!(bidi_info.paragraphs.len(), 3); |
| let p_ltr = Paragraph::new(&bidi_info, &bidi_info.paragraphs[0]); |
| let p_rtl = Paragraph::new(&bidi_info, &bidi_info.paragraphs[1]); |
| let p_mixed = Paragraph::new(&bidi_info, &bidi_info.paragraphs[2]); |
| assert_eq!(p_ltr.direction(), Direction::Ltr); |
| assert_eq!(p_rtl.direction(), Direction::Rtl); |
| assert_eq!(p_mixed.direction(), Direction::Mixed); |
| } |
| |
| #[test] |
| fn test_edge_cases_direction() { |
| // No paragraphs for empty text. |
| let empty = ""; |
| let bidi_info = BidiInfo::new(empty, Option::from(RTL_LEVEL)); |
| assert_eq!(bidi_info.paragraphs.len(), 0); |
| // The paragraph separator will take the value of the default direction |
| // which is left to right. |
| let empty = "\n"; |
| let bidi_info = BidiInfo::new(empty, None); |
| assert_eq!(bidi_info.paragraphs.len(), 1); |
| let p = Paragraph::new(&bidi_info, &bidi_info.paragraphs[0]); |
| assert_eq!(p.direction(), Direction::Ltr); |
| // The paragraph separator will take the value of the given initial direction |
| // which is left to right. |
| let empty = "\n"; |
| let bidi_info = BidiInfo::new(empty, Option::from(LTR_LEVEL)); |
| assert_eq!(bidi_info.paragraphs.len(), 1); |
| let p = Paragraph::new(&bidi_info, &bidi_info.paragraphs[0]); |
| assert_eq!(p.direction(), Direction::Ltr); |
| |
| // The paragraph separator will take the value of the given initial direction |
| // which is right to left. |
| let empty = "\n"; |
| let bidi_info = BidiInfo::new(empty, Option::from(RTL_LEVEL)); |
| assert_eq!(bidi_info.paragraphs.len(), 1); |
| let p = Paragraph::new(&bidi_info, &bidi_info.paragraphs[0]); |
| assert_eq!(p.direction(), Direction::Rtl); |
| } |
| |
| #[test] |
| fn test_level_at() { |
| let ltr_text = "hello world"; |
| let rtl_text = "أهلا بكم"; |
| let all_paragraphs = format!("{}\n{}\n{}{}", ltr_text, rtl_text, ltr_text, rtl_text); |
| let bidi_info = BidiInfo::new(&all_paragraphs, None); |
| assert_eq!(bidi_info.paragraphs.len(), 3); |
| |
| let p_ltr = Paragraph::new(&bidi_info, &bidi_info.paragraphs[0]); |
| let p_rtl = Paragraph::new(&bidi_info, &bidi_info.paragraphs[1]); |
| let p_mixed = Paragraph::new(&bidi_info, &bidi_info.paragraphs[2]); |
| |
| assert_eq!(p_ltr.level_at(0), LTR_LEVEL); |
| assert_eq!(p_rtl.level_at(0), RTL_LEVEL); |
| assert_eq!(p_mixed.level_at(0), LTR_LEVEL); |
| assert_eq!(p_mixed.info.levels.len(), 54); |
| assert_eq!(p_mixed.para.range.start, 28); |
| assert_eq!(p_mixed.level_at(ltr_text.len()), RTL_LEVEL); |
| } |
| } |
| |
| #[cfg(all(feature = "serde", feature = "hardcoded-data", test))] |
| mod serde_tests { |
| use super::*; |
| use serde_test::{assert_tokens, Token}; |
| |
| #[test] |
| fn test_levels() { |
| let text = "abc אבג"; |
| let bidi_info = BidiInfo::new(text, None); |
| let levels = bidi_info.levels; |
| assert_eq!(text.as_bytes().len(), 10); |
| assert_eq!(levels.len(), 10); |
| assert_tokens( |
| &levels, |
| &[ |
| Token::Seq { len: Some(10) }, |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(0), |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(0), |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(0), |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(0), |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(1), |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(1), |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(1), |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(1), |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(1), |
| Token::NewtypeStruct { name: "Level" }, |
| Token::U8(1), |
| Token::SeqEnd, |
| ], |
| ); |
| } |
| } |
