From 9275021497fc13938317b681319ba571c8d5f478 Mon Sep 17 00:00:00 2001 From: Blaž Hrastnik Date: Fri, 18 Jun 2021 17:31:31 +0900 Subject: ui: prompt: Better unicode support We copied over eval_movement from wezterm, that already solves most of our problems. self.cursor is now byte-based. --- helix-term/src/ui/prompt.rs | 181 +++++++++++++++++++++++++++++++++----------- 1 file changed, 137 insertions(+), 44 deletions(-) (limited to 'helix-term/src') diff --git a/helix-term/src/ui/prompt.rs b/helix-term/src/ui/prompt.rs index 991b328d..d1413209 100644 --- a/helix-term/src/ui/prompt.rs +++ b/helix-term/src/ui/prompt.rs @@ -6,6 +6,9 @@ use helix_view::{Editor, Theme}; use std::{borrow::Cow, ops::RangeFrom}; use tui::terminal::CursorKind; +use unicode_segmentation::{GraphemeCursor, GraphemeIncomplete}; +use unicode_width::UnicodeWidthStr; + pub type Completion = (RangeFrom, Cow<'static, str>); pub struct Prompt { @@ -34,6 +37,17 @@ pub enum CompletionDirection { Backward, } +#[derive(Debug, Clone, Copy)] +pub enum Movement { + BackwardChar(usize), + BackwardWord(usize), + ForwardChar(usize), + ForwardWord(usize), + StartOfLine, + EndOfLine, + None, +} + impl Prompt { pub fn new( prompt: String, @@ -52,30 +66,125 @@ impl Prompt { } } + /// Compute the cursor position after applying movement + /// Taken from: https://github.com/wez/wezterm/blob/e0b62d07ca9bf8ce69a61e30a3c20e7abc48ce7e/termwiz/src/lineedit/mod.rs#L516-L611 + fn eval_movement(&self, movement: Movement) -> usize { + match movement { + Movement::BackwardChar(rep) => { + let mut position = self.cursor; + for _ in 0..rep { + let mut cursor = GraphemeCursor::new(position, self.line.len(), false); + if let Ok(Some(pos)) = cursor.prev_boundary(&self.line, 0) { + position = pos; + } else { + break; + } + } + position + } + Movement::BackwardWord(rep) => { + let char_indices: Vec<(usize, char)> = self.line.char_indices().collect(); + if char_indices.is_empty() { + return self.cursor; + } + let mut char_position = char_indices + .iter() + .position(|(idx, _)| *idx == self.cursor) + .unwrap_or(char_indices.len() - 1); + + for _ in 0..rep { + if char_position == 0 { + break; + } + + let mut found = None; + for prev in (0..char_position - 1).rev() { + if char_indices[prev].1.is_whitespace() { + found = Some(prev + 1); + break; + } + } + + char_position = found.unwrap_or(0); + } + char_indices[char_position].0 + } + Movement::ForwardWord(rep) => { + let char_indices: Vec<(usize, char)> = self.line.char_indices().collect(); + if char_indices.is_empty() { + return self.cursor; + } + let mut char_position = char_indices + .iter() + .position(|(idx, _)| *idx == self.cursor) + .unwrap_or_else(|| char_indices.len()); + + for _ in 0..rep { + // Skip any non-whitespace characters + while char_position < char_indices.len() + && !char_indices[char_position].1.is_whitespace() + { + char_position += 1; + } + + // Skip any whitespace characters + while char_position < char_indices.len() + && char_indices[char_position].1.is_whitespace() + { + char_position += 1; + } + + // We are now on the start of the next word + } + char_indices + .get(char_position) + .map(|(i, _)| *i) + .unwrap_or_else(|| self.line.len()) + } + Movement::ForwardChar(rep) => { + let mut position = self.cursor; + for _ in 0..rep { + let mut cursor = GraphemeCursor::new(position, self.line.len(), false); + if let Ok(Some(pos)) = cursor.next_boundary(&self.line, 0) { + position = pos; + } else { + break; + } + } + position + } + Movement::StartOfLine => 0, + Movement::EndOfLine => { + let mut cursor = + GraphemeCursor::new(self.line.len().saturating_sub(1), self.line.len(), false); + if let Ok(Some(pos)) = cursor.next_boundary(&self.line, 0) { + pos + } else { + self.cursor + } + } + Movement::None => self.cursor, + } + } + pub fn insert_char(&mut self, c: char) { - let pos = if self.line.is_empty() { - 0 - } else { - self.line - .char_indices() - .nth(self.cursor) - .map(|(pos, _)| pos) - .unwrap_or_else(|| self.line.len()) - }; - self.line.insert(pos, c); - self.cursor += 1; + self.line.insert(self.cursor, c); + let mut cursor = GraphemeCursor::new(self.cursor, self.line.len(), false); + if let Ok(Some(pos)) = cursor.next_boundary(&self.line, 0) { + self.cursor = pos; + } self.completion = (self.completion_fn)(&self.line); self.exit_selection(); } pub fn move_char_left(&mut self) { - self.cursor = self.cursor.saturating_sub(1) + let pos = self.eval_movement(Movement::BackwardChar(1)); + self.cursor = pos } pub fn move_char_right(&mut self) { - if self.cursor < self.line.len() { - self.cursor += 1; - } + let pos = self.eval_movement(Movement::ForwardChar(1)); + self.cursor = pos; } pub fn move_start(&mut self) { @@ -87,39 +196,21 @@ impl Prompt { } pub fn delete_char_backwards(&mut self) { - if self.cursor > 0 { - let pos = self - .line - .char_indices() - .nth(self.cursor - 1) - .map(|(pos, _)| pos) - .expect("line is not empty"); - self.line.remove(pos); - self.cursor -= 1; - self.completion = (self.completion_fn)(&self.line); - } + let pos = self.eval_movement(Movement::BackwardChar(1)); + self.line.replace_range(pos..self.cursor, ""); + self.cursor = pos; + self.exit_selection(); + self.completion = (self.completion_fn)(&self.line); } pub fn delete_word_backwards(&mut self) { - use helix_core::get_general_category; - let mut chars = self.line.char_indices().rev(); - // TODO add skipping whitespace logic here - let (mut i, cat) = match chars.next() { - Some((i, c)) => (i, get_general_category(c)), - None => return, - }; - self.cursor -= 1; - for (nn, nc) in chars { - if get_general_category(nc) != cat { - break; - } - i = nn; - self.cursor -= 1; - } - self.line.drain(i..); - self.completion = (self.completion_fn)(&self.line); + let pos = self.eval_movement(Movement::BackwardWord(1)); + self.line.replace_range(pos..self.cursor, ""); + self.cursor = pos; + self.exit_selection(); + self.completion = (self.completion_fn)(&self.line); } pub fn clear(&mut self) { @@ -363,7 +454,9 @@ impl Component for Prompt { ( Some(Position::new( area.y as usize + line, - area.x as usize + self.prompt.len() + self.cursor, + area.x as usize + + self.prompt.len() + + UnicodeWidthStr::width(&self.line[..self.cursor]), )), CursorKind::Block, ) -- cgit v1.2.3-70-g09d2