bendns' repos / helix
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'helix-term/src/ui/markdown.rs')
-rw-r--r--helix-term/src/ui/markdown.rs392
1 files changed, 0 insertions, 392 deletions
diff --git a/helix-term/src/ui/markdown.rs b/helix-term/src/ui/markdown.rs
deleted file mode 100644
index 6bef59d1..00000000
--- a/helix-term/src/ui/markdown.rs
+++ /dev/null
@@ -1,392 +0,0 @@
-use crate::compositor::{Component, Context};
-use arc_swap::ArcSwap;
-use tui::{
- buffer::Buffer as Surface,
- text::{Span, Spans, Text},
-};
-
-use std::sync::Arc;
-
-use pulldown_cmark::{CodeBlockKind, Event, HeadingLevel, Options, Parser, Tag, TagEnd};
-
-use helix_core::{
- syntax::{self, HighlightEvent, OverlayHighlights},
- RopeSlice, Syntax,
-};
-use helix_view::{
- graphics::{Margin, Rect, Style},
- theme::Modifier,
- Theme,
-};
-
-fn styled_multiline_text<'a>(text: &str, style: Style) -> Text<'a> {
- let spans: Vec<_> = text
- .lines()
- .map(|line| Span::styled(line.to_string(), style))
- .map(Spans::from)
- .collect();
- Text::from(spans)
-}
-
-pub fn highlighted_code_block<'a>(
- text: &str,
- language: &str,
- theme: Option<&Theme>,
- loader: &syntax::Loader,
- // Optional overlay highlights to mix in with the syntax highlights.
- //
- // Note that `OverlayHighlights` is typically used with char indexing but the only caller
- // which passes this parameter currently passes **byte indices** instead.
- additional_highlight_spans: Option<OverlayHighlights>,
-) -> Text<'a> {
- let mut spans = Vec::new();
- let mut lines = Vec::new();
-
- let get_theme = |key: &str| -> Style { theme.map(|t| t.get(key)).unwrap_or_default() };
- let text_style = get_theme(Markdown::TEXT_STYLE);
- let code_style = get_theme(Markdown::BLOCK_STYLE);
-
- let theme = match theme {
- Some(t) => t,
- None => return styled_multiline_text(text, code_style),
- };
-
- let ropeslice = RopeSlice::from(text);
- let Some(syntax) = loader
- .language_for_match(RopeSlice::from(language))
- .and_then(|lang| Syntax::new(ropeslice, lang, loader).ok())
- else {
- return styled_multiline_text(text, code_style);
- };
-
- let mut syntax_highlighter = syntax.highlighter(ropeslice, loader, ..);
- let mut syntax_highlight_stack = Vec::new();
- let mut overlay_highlight_stack = Vec::new();
- let mut overlay_highlighter = syntax::OverlayHighlighter::new(additional_highlight_spans);
- let mut pos = 0;
-
- while pos < ropeslice.len_bytes() as u32 {
- if pos == syntax_highlighter.next_event_offset() {
- let (event, new_highlights) = syntax_highlighter.advance();
- if event == HighlightEvent::Refresh {
- syntax_highlight_stack.clear();
- }
- syntax_highlight_stack.extend(new_highlights);
- } else if pos == overlay_highlighter.next_event_offset() as u32 {
- let (event, new_highlights) = overlay_highlighter.advance();
- if event == HighlightEvent::Refresh {
- overlay_highlight_stack.clear();
- }
- overlay_highlight_stack.extend(new_highlights)
- }
-
- let start = pos;
- pos = syntax_highlighter
- .next_event_offset()
- .min(overlay_highlighter.next_event_offset() as u32);
- if pos == u32::MAX {
- pos = ropeslice.len_bytes() as u32;
- }
- if pos == start {
- continue;
- }
- // The highlighter should always move forward.
- // If the highlighter malfunctions, bail on syntax highlighting and log an error.
- debug_assert!(pos > start);
- if pos < start {
- log::error!("Failed to highlight '{language}': {text:?}");
- return styled_multiline_text(text, code_style);
- }
-
- let style = syntax_highlight_stack
- .iter()
- .chain(overlay_highlight_stack.iter())
- .fold(text_style, |acc, highlight| {
- acc.patch(theme.highlight(*highlight))
- });
-
- let mut slice = &text[start as usize..pos as usize];
- // TODO: do we need to handle all unicode line endings
- // here, or is just '\n' okay?
- while let Some(end) = slice.find('\n') {
- // emit span up to newline
- let text = &slice[..end];
- let text = text.replace('\t', " "); // replace tabs
- let span = Span::styled(text, style);
- spans.push(span);
-
- // truncate slice to after newline
- slice = &slice[end + 1..];
-
- // make a new line
- let spans = std::mem::take(&mut spans);
- lines.push(Spans::from(spans));
- }
-
- if !slice.is_empty() {
- let span = Span::styled(slice.replace('\t', " "), style);
- spans.push(span);
- }
- }
-
- if !spans.is_empty() {
- let spans = std::mem::take(&mut spans);
- lines.push(Spans::from(spans));
- }
-
- Text::from(lines)
-}
-
-pub struct Markdown {
- contents: String,
-
- config_loader: Arc<ArcSwap<syntax::Loader>>,
-}
-
-// TODO: pre-render and self reference via Pin
-// better yet, just use Tendril + subtendril for references
-
-impl Markdown {
- const TEXT_STYLE: &'static str = "ui.text";
- const BLOCK_STYLE: &'static str = "markup.raw.inline";
- const RULE_STYLE: &'static str = "punctuation.special";
- const UNNUMBERED_LIST_STYLE: &'static str = "markup.list.unnumbered";
- const NUMBERED_LIST_STYLE: &'static str = "markup.list.numbered";
- const HEADING_STYLES: [&'static str; 6] = [
- "markup.heading.1",
- "markup.heading.2",
- "markup.heading.3",
- "markup.heading.4",
- "markup.heading.5",
- "markup.heading.6",
- ];
- const INDENT: &'static str = " ";
-
- pub fn new(contents: String, config_loader: Arc<ArcSwap<syntax::Loader>>) -> Self {
- Self {
- contents,
- config_loader,
- }
- }
-
- pub fn parse(&self, theme: Option<&Theme>) -> tui::text::Text<'_> {
- fn push_line<'a>(spans: &mut Vec<Span<'a>>, lines: &mut Vec<Spans<'a>>) {
- let spans = std::mem::take(spans);
- if !spans.is_empty() {
- lines.push(Spans::from(spans));
- }
- }
-
- let mut options = Options::empty();
- options.insert(Options::ENABLE_STRIKETHROUGH);
- let parser = Parser::new_ext(&self.contents, options);
-
- // TODO: if possible, render links as terminal hyperlinks: https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda
- let mut tags = Vec::new();
- let mut spans = Vec::new();
- let mut lines = Vec::new();
- let mut list_stack = Vec::new();
-
- let get_indent = |level: usize| {
- if level < 1 {
- String::new()
- } else {
- Self::INDENT.repeat(level - 1)
- }
- };
-
- let get_theme = |key: &str| -> Style { theme.map(|t| t.get(key)).unwrap_or_default() };
- let text_style = get_theme(Self::TEXT_STYLE);
- let code_style = get_theme(Self::BLOCK_STYLE);
- let numbered_list_style = get_theme(Self::NUMBERED_LIST_STYLE);
- let unnumbered_list_style = get_theme(Self::UNNUMBERED_LIST_STYLE);
- let rule_style = get_theme(Self::RULE_STYLE);
- let heading_styles: Vec<Style> = Self::HEADING_STYLES
- .iter()
- .map(|key| get_theme(key))
- .collect();
-
- // Transform text in `<code>` blocks into `Event::Code`
- let mut in_code = false;
- let parser = parser.filter_map(|event| match event {
- Event::Html(tag)
- if tag.starts_with("<code") && matches!(tag.chars().nth(5), Some(' ' | '>')) =>
- {
- in_code = true;
- None
- }
- Event::Html(tag) if *tag == *"</code>" => {
- in_code = false;
- None
- }
- Event::Text(text) if in_code => Some(Event::Code(text)),
- _ => Some(event),
- });
-
- for event in parser {
- match event {
- Event::Start(Tag::List(list)) => {
- // if the list stack is not empty this is a sub list, in that
- // case we need to push the current line before proceeding
- if !list_stack.is_empty() {
- push_line(&mut spans, &mut lines);
- }
-
- list_stack.push(list);
- }
- Event::End(TagEnd::List(_)) => {
- list_stack.pop();
-
- // whenever top-level list closes, empty line
- if list_stack.is_empty() {
- lines.push(Spans::default());
- }
- }
- Event::Start(Tag::Item) => {
- if list_stack.is_empty() {
- log::warn!("markdown parsing error, list item without list");
- }
-
- tags.push(Tag::Item);
-
- // get the appropriate bullet for the current list
- let (bullet, bullet_style) = list_stack
- .last()
- .unwrap_or(&None) // use the '- ' bullet in case the list stack would be empty
- .map_or((String::from("• "), unnumbered_list_style), |number| {
- (format!("{}. ", number), numbered_list_style)
- });
-
- // increment the current list number if there is one
- if let Some(v) = list_stack.last_mut().unwrap_or(&mut None).as_mut() {
- *v += 1;
- }
-
- let prefix = get_indent(list_stack.len()) + bullet.as_str();
- spans.push(Span::styled(prefix, bullet_style));
- }
- Event::Start(tag) => {
- tags.push(tag);
- if spans.is_empty() && !list_stack.is_empty() {
- // TODO: could push indent + 2 or 3 spaces to align with
- // the rest of the list.
- spans.push(Span::from(get_indent(list_stack.len())));
- }
- }
- Event::End(tag) => {
- tags.pop();
- match tag {
- TagEnd::Heading(_)
- | TagEnd::Paragraph
- | TagEnd::CodeBlock
- | TagEnd::Item => {
- push_line(&mut spans, &mut lines);
- }
- _ => (),
- }
-
- // whenever heading, code block or paragraph closes, empty line
- match tag {
- TagEnd::Heading(_) | TagEnd::Paragraph | TagEnd::CodeBlock => {
- lines.push(Spans::default());
- }
- _ => (),
- }
- }
- Event::Text(text) => {
- if let Some(Tag::CodeBlock(kind)) = tags.last() {
- let language = match kind {
- CodeBlockKind::Fenced(language) => language,
- CodeBlockKind::Indented => "",
- };
- let tui_text = highlighted_code_block(
- &text,
- language,
- theme,
- &self.config_loader.load(),
- None,
- );
- lines.extend(tui_text.lines.into_iter());
- } else {
- let style = match tags.last() {
- Some(Tag::Heading { level, .. }) => match level {
- HeadingLevel::H1 => heading_styles[0],
- HeadingLevel::H2 => heading_styles[1],
- HeadingLevel::H3 => heading_styles[2],
- HeadingLevel::H4 => heading_styles[3],
- HeadingLevel::H5 => heading_styles[4],
- HeadingLevel::H6 => heading_styles[5],
- },
- Some(Tag::Emphasis) => text_style.add_modifier(Modifier::ITALIC),
- Some(Tag::Strong) => text_style.add_modifier(Modifier::BOLD),
- Some(Tag::Strikethrough) => {
- text_style.add_modifier(Modifier::CROSSED_OUT)
- }
- _ => text_style,
- };
- spans.push(Span::styled(text, style));
- }
- }
- Event::Code(text) | Event::Html(text) => {
- spans.push(Span::styled(text, code_style));
- }
- Event::SoftBreak | Event::HardBreak => {
- push_line(&mut spans, &mut lines);
- if !list_stack.is_empty() {
- // TODO: could push indent + 2 or 3 spaces to align with
- // the rest of the list.
- spans.push(Span::from(get_indent(list_stack.len())));
- }
- }
- Event::Rule => {
- lines.push(Spans::from(Span::styled("───", rule_style)));
- lines.push(Spans::default());
- }
- // TaskListMarker(bool) true if checked
- _ => {
- log::warn!("unhandled markdown event {:?}", event);
- }
- }
- // build up a vec of Paragraph tui widgets
- }
-
- if !spans.is_empty() {
- lines.push(Spans::from(spans));
- }
-
- // if last line is empty, remove it
- if let Some(line) = lines.last() {
- if line.0.is_empty() {
- lines.pop();
- }
- }
-
- Text::from(lines)
- }
-}
-
-impl Component for Markdown {
- fn render(&mut self, area: Rect, surface: &mut Surface, cx: &mut Context) {
- use tui::widgets::{Paragraph, Widget, Wrap};
-
- let text = self.parse(Some(&cx.editor.theme));
-
- let par = Paragraph::new(&text)
- .wrap(Wrap { trim: false })
- .scroll((cx.scroll.unwrap_or_default() as u16, 0));
-
- let margin = Margin::all(1);
- par.render(area.inner(margin), surface);
- }
-
- fn required_size(&mut self, viewport: (u16, u16)) -> Option<(u16, u16)> {
- let padding = 2;
- let contents = self.parse(None);
-
- // TODO: account for tab width
- let max_text_width = (viewport.0.saturating_sub(padding)).min(120);
- let (width, height) = crate::ui::text::required_size(&contents, max_text_width);
-
- Some((width + padding, height + padding))
- }
-}