Pull in all of bat's syntect themes

Cargo.lock

@@ -903,6 +903,7 @@ dependencies = [
  "clap",
  "comrak",
  "crossterm",
+ "flate2",
  "hex",
  "image",
  "itertools",

Cargo.toml

@@ -13,6 +13,7 @@ clap = { version = "4.4", features = ["derive", "string"] }
 comrak = { version = "0.19", default-features = false }
 crossterm = { version = "0.27", features = ["serde"] }
 hex = "0.4"
+flate2 = "1.0"
 image = "0.24"
 merge-struct = "0.1.0"
 itertools = "0.11"

bat/update.sh

@@ -19,6 +19,7 @@ cd $clone_path
 git reset --hard $git_hash
 
 cp assets/syntaxes.bin "$script_dir"
+cp assets/themes.bin "$script_dir"
 
 acknowledgements_file="$script_dir/acknowledgements.txt"
 cp LICENSE-MIT "$acknowledgements_file"

src/builder.rs

@@ -490,7 +490,7 @@ impl<'a> PresentationBuilder<'a> {
         let mut code_highlighter = self.highlighter.language_highlighter(&code.language);
         let padding_style = {
             let mut highlighter = self.highlighter.language_highlighter(&CodeLanguage::Rust);
-            highlighter.style_line("//").first().expect("no styles").style
+            highlighter.style_line("//").next().expect("no styles").style
         };
         let groups = match self.options.allow_mutations {
             true => code.attributes.highlight_groups.clone(),
@@ -669,8 +669,6 @@ impl CodeLine {
     fn highlight(&self, padding_style: &Style, code_highlighter: &mut LanguageHighlighter) -> String {
         let mut output = StyledTokens { style: *padding_style, tokens: &self.prefix }.apply_style();
         output.push_str(&code_highlighter.highlight_line(&self.code));
-        // Remove newline
-        output.pop();
         output.push_str(&StyledTokens { style: *padding_style, tokens: &self.suffix }.apply_style());
         output
     }
@@ -1147,7 +1145,7 @@ mod test {
     }
 
     fn try_build_presentation(elements: Vec<MarkdownElement>) -> Result<Presentation, BuildError> {
-        let highlighter = CodeHighlighter::new("base16-ocean.dark").unwrap();
+        let highlighter = CodeHighlighter::default();
         let theme = PresentationTheme::default();
         let mut resources = Resources::new("/tmp");
         let options = PresentationBuilderOptions::default();

src/export.rs

@@ -172,7 +172,7 @@ mod test {
         let arena = Arena::new();
         let parser = MarkdownParser::new(&arena);
         let theme = Default::default();
-        let highlighter = CodeHighlighter::new("base16-ocean.dark").unwrap();
+        let highlighter = CodeHighlighter::default();
         let resources = Resources::new("examples");
         let mut exporter = Exporter::new(parser, &theme, highlighter, resources);
         exporter.extract_metadata(content, Path::new(path)).expect("metadata extraction failed")

src/main.rs

@@ -74,7 +74,7 @@ fn run(cli: Cli) -> Result<(), Box<dyn std::error::Error>> {
     };
     let arena = Arena::new();
     let parser = MarkdownParser::new(&arena);
-    let default_highlighter = CodeHighlighter::new("base16-ocean.dark")?;
+    let default_highlighter = CodeHighlighter::default();
     if cli.acknowledgements {
         display_acknowledgements();
         return Ok(());

src/render/highlighting.rs

@@ -1,28 +1,76 @@
 use crate::markdown::elements::CodeLanguage;
+use crossterm::{
+    style::{SetBackgroundColor, SetForegroundColor},
+    QueueableCommand,
+};
+use flate2::read::ZlibDecoder;
 use once_cell::sync::Lazy;
+use serde::Deserialize;
+use std::{
+    collections::BTreeMap,
+    io::{self, Write},
+    sync::{Arc, Mutex},
+};
 use syntect::{
     easy::HighlightLines,
     highlighting::{Style, Theme, ThemeSet},
     parsing::SyntaxSet,
-    util::as_24_bit_terminal_escaped,
 };
 
 static SYNTAX_SET: Lazy<SyntaxSet> = Lazy::new(|| {
     let contents = include_bytes!("../../bat/syntaxes.bin");
     bincode::deserialize(contents).expect("syntaxes are broken")
 });
-static THEMES: Lazy<ThemeSet> = Lazy::new(ThemeSet::load_defaults);
+
+static THEMES: Lazy<LazyThemeSet> = Lazy::new(|| {
+    let contents = include_bytes!("../../bat/themes.bin");
+    let theme_set: LazyThemeSet = bincode::deserialize(contents).expect("syntaxes are broken");
+    let default_themes = ThemeSet::load_defaults();
+    theme_set.merge(default_themes);
+    theme_set
+});
+
+// This structure mimic's `bat`'s serialized theme set's.
+#[derive(Debug, Deserialize)]
+struct LazyThemeSet {
+    serialized_themes: BTreeMap<String, Vec<u8>>,
+    #[serde(skip)]
+    themes: Mutex<BTreeMap<String, Arc<Theme>>>,
+}
+
+impl LazyThemeSet {
+    fn merge(&self, themes: ThemeSet) {
+        let mut all_themes = self.themes.lock().unwrap();
+        for (name, theme) in themes.themes {
+            if !self.serialized_themes.contains_key(&name) {
+                all_themes.insert(name, theme.into());
+            }
+        }
+    }
+
+    fn get(&self, theme_name: &str) -> Option<Arc<Theme>> {
+        let mut themes = self.themes.lock().unwrap();
+        if let Some(theme) = themes.get(theme_name) {
+            return Some(theme.clone());
+        }
+        let serialized = self.serialized_themes.get(theme_name)?;
+        let decoded: Theme = bincode::deserialize_from(ZlibDecoder::new(serialized.as_slice())).ok()?;
+        let decoded = Arc::new(decoded);
+        themes.insert(theme_name.to_string(), decoded);
+        themes.get(theme_name).cloned()
+    }
+}
 
 /// A code highlighter.
 #[derive(Clone)]
 pub struct CodeHighlighter {
-    theme: &'static Theme,
+    theme: Arc<Theme>,
 }
 
 impl CodeHighlighter {
     /// Construct a new highlighted using the given [syntect] theme name.
     pub fn new(theme: &str) -> Result<Self, ThemeNotFound> {
-        let theme = THEMES.themes.get(theme).ok_or(ThemeNotFound)?;
+        let theme = THEMES.get(theme).ok_or(ThemeNotFound)?;
         Ok(Self { theme })
     }
 
@@ -30,7 +78,7 @@ impl CodeHighlighter {
     pub(crate) fn language_highlighter(&self, language: &CodeLanguage) -> LanguageHighlighter {
         let extension = Self::language_extension(language);
         let syntax = SYNTAX_SET.find_syntax_by_extension(extension).unwrap();
-        let highlighter = HighlightLines::new(syntax, self.theme);
+        let highlighter = HighlightLines::new(syntax, &self.theme);
         LanguageHighlighter { highlighter }
     }
 
@@ -90,23 +138,28 @@ impl CodeHighlighter {
         }
     }
 }
-pub(crate) struct LanguageHighlighter {
-    highlighter: HighlightLines<'static>,
+
+impl Default for CodeHighlighter {
+    fn default() -> Self {
+        Self::new("base16-eighties.dark").expect("default theme not found")
+    }
 }
 
-impl LanguageHighlighter {
+pub(crate) struct LanguageHighlighter<'a> {
+    highlighter: HighlightLines<'a>,
+}
+
+impl<'a> LanguageHighlighter<'a> {
     pub(crate) fn highlight_line(&mut self, line: &str) -> String {
-        let ranges = self.highlighter.highlight_line(line, &SYNTAX_SET).unwrap();
-        as_24_bit_terminal_escaped(&ranges, true)
+        self.style_line(line).map(|s| s.apply_style()).collect()
     }
 
-    pub(crate) fn style_line<'a>(&mut self, line: &'a str) -> Vec<StyledTokens<'a>> {
+    pub(crate) fn style_line<'b>(&mut self, line: &'b str) -> impl Iterator<Item = StyledTokens<'b>> {
         self.highlighter
             .highlight_line(line, &SYNTAX_SET)
             .unwrap()
             .into_iter()
             .map(|(style, tokens)| StyledTokens { style, tokens })
-            .collect()
     }
 }
 
@@ -117,7 +170,29 @@ pub(crate) struct StyledTokens<'a> {
 
 impl<'a> StyledTokens<'a> {
     pub(crate) fn apply_style(&self) -> String {
-        as_24_bit_terminal_escaped(&[(self.style, self.tokens)], true)
+        let background = to_ansi_color(self.style.background);
+        let foreground = to_ansi_color(self.style.foreground);
+
+        // We do this conversion manually as crossterm will reset the color after styling, and we
+        // want to "keep it open" so that padding also uses this background color.
+        //
+        // Note: these unwraps shouldn't happen as this is an in-memory writer so there's no
+        // fallible IO here.
+        let mut cursor = io::BufWriter::new(Vec::new());
+        if let Some(color) = background {
+            cursor.queue(SetBackgroundColor(color)).unwrap();
+        }
+        if let Some(color) = foreground {
+            cursor.queue(SetForegroundColor(color)).unwrap();
+        }
+        // syntect likes its input to contain \n but we don't want them as we pad text with extra
+        // " " at the end so we get rid of them here.
+        for chunk in self.tokens.split('\n') {
+            cursor.write_all(chunk.as_bytes()).unwrap();
+        }
+
+        cursor.flush().unwrap();
+        String::from_utf8(cursor.into_inner().unwrap()).unwrap()
     }
 }
 
@@ -126,6 +201,28 @@ impl<'a> StyledTokens<'a> {
 #[error("theme not found")]
 pub struct ThemeNotFound;
 
+// This code has been adapted from bat's: https://github.com/sharkdp/bat
+fn to_ansi_color(color: syntect::highlighting::Color) -> Option<crossterm::style::Color> {
+    use crossterm::style::Color;
+    if color.a == 0 {
+        Some(match color.r {
+            0x00 => Color::Black,
+            0x01 => Color::DarkRed,
+            0x02 => Color::DarkGreen,
+            0x03 => Color::DarkYellow,
+            0x04 => Color::DarkBlue,
+            0x05 => Color::DarkMagenta,
+            0x06 => Color::DarkCyan,
+            0x07 => Color::Grey,
+            n => Color::AnsiValue(n),
+        })
+    } else if color.a == 1 {
+        None
+    } else {
+        Some(Color::Rgb { r: color.r, g: color.g, b: color.b })
+    }
+}
+
 #[cfg(test)]
 mod test {
     use super::*;
@@ -139,4 +236,9 @@ mod test {
             assert!(syntax.is_some(), "extension {extension} for {language:?} not found");
         }
     }
+
+    #[test]
+    fn default_highlighter() {
+        CodeHighlighter::default();
+    }
 }

themes/light.yaml

@@ -17,7 +17,7 @@ code:
   minimum_size: 50
   minimum_margin:
     percent: 8
-  theme_name: InspiredGitHub
+  theme_name: GitHub
   padding:
     horizontal: 2
     vertical: 1