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|
use std::io::Write;
use syntect::easy::HighlightLines;
use syntect::highlighting::{Style, StyleModifier};
use syntect::parsing::SyntaxReference;
use unicode_segmentation::UnicodeSegmentation;
use crate::bat::assets::HighlightingAssets;
use crate::config;
use crate::edits;
use crate::paint::superimpose_style_sections::superimpose_style_sections;
use crate::style;
pub struct Painter<'a> {
pub minus_lines: Vec<String>,
pub plus_lines: Vec<String>,
pub writer: &'a mut dyn Write,
pub syntax: Option<&'a SyntaxReference>,
pub highlighter: HighlightLines<'a>,
pub config: &'a config::Config<'a>,
pub output_buffer: String,
}
impl<'a> Painter<'a> {
pub fn new(
writer: &'a mut dyn Write,
config: &'a config::Config,
assets: &'a HighlightingAssets,
) -> Self {
let dummy_highlighter = HighlightLines::new(
assets.syntax_set.find_syntax_by_extension("txt").unwrap(),
&assets.theme_set.themes[style::DEFAULT_LIGHT_THEME],
);
Self {
minus_lines: Vec::new(),
plus_lines: Vec::new(),
output_buffer: String::new(),
syntax: None,
highlighter: dummy_highlighter,
writer,
config,
}
}
pub fn reset_highlighter(&mut self) {
if let Some(theme) = self.config.theme {
self.highlighter = HighlightLines::new(self.syntax.unwrap(), theme)
};
}
pub fn paint_buffered_lines(&mut self) {
let (minus_line_syntax_style_sections, plus_line_syntax_style_sections) =
Self::get_syntax_style_sections(
&self.minus_lines,
&self.plus_lines,
&mut self.highlighter,
self.config,
);
let (minus_line_diff_style_sections, plus_line_diff_style_sections) =
Self::get_diff_style_sections(&self.minus_lines, &self.plus_lines, self.config);
// TODO: lines and style sections contain identical line text
if !self.minus_lines.is_empty() {
Painter::paint_lines(
&mut self.output_buffer,
minus_line_syntax_style_sections,
minus_line_diff_style_sections,
self.config,
self.config.minus_style_modifier,
true,
);
}
if !self.plus_lines.is_empty() {
Painter::paint_lines(
&mut self.output_buffer,
plus_line_syntax_style_sections,
plus_line_diff_style_sections,
self.config,
self.config.plus_style_modifier,
true,
);
}
self.minus_lines.clear();
self.plus_lines.clear();
}
/// Superimpose background styles and foreground syntax
/// highlighting styles, and write colored lines to output buffer.
pub fn paint_lines(
output_buffer: &mut String,
syntax_style_sections: Vec<Vec<(Style, &str)>>,
diff_style_sections: Vec<Vec<(StyleModifier, &str)>>,
config: &config::Config,
background_style_modifier: StyleModifier,
should_trim_newline_and_right_pad: bool,
) {
use std::fmt::Write;
for (syntax_sections, diff_sections) in
syntax_style_sections.iter().zip(diff_style_sections.iter())
{
let mut text_width = 0;
for (style, text) in superimpose_style_sections(syntax_sections, diff_sections) {
paint_text(&text, style, output_buffer).unwrap();
if config.width.is_some() {
text_width += text.graphemes(true).count();
}
}
if should_trim_newline_and_right_pad {
// Remove the terminating newline whose presence was necessary for the syntax
// highlighter to work correctly.
output_buffer.truncate(output_buffer.len() - 1);
// Right pad with background-highlighted white space.
match config.width {
Some(width) if width > text_width => {
// Right pad to requested width with spaces.
let background_style = config.no_style.apply(background_style_modifier);
paint_text(
&" ".repeat(width - text_width),
background_style,
output_buffer,
)
.unwrap();
}
_ => (),
}
}
writeln!(output_buffer).unwrap();
}
}
/// Write output buffer to output stream, and clear the buffer.
pub fn emit(&mut self) -> std::io::Result<()> {
write!(self.writer, "{}", self.output_buffer)?;
self.output_buffer.clear();
Ok(())
}
/// Perform syntax highlighting for minus and plus lines in buffer.
fn get_syntax_style_sections<'m, 'p>(
minus_lines: &'m [String],
plus_lines: &'p [String],
highlighter: &mut HighlightLines,
config: &config::Config,
) -> (Vec<Vec<(Style, &'m str)>>, Vec<Vec<(Style, &'p str)>>) {
let mut minus_line_sections = Vec::new();
for line in minus_lines.iter() {
minus_line_sections.push(Painter::get_line_syntax_style_sections(
&line,
highlighter,
&config,
config.opt.highlight_removed,
));
}
let mut plus_line_sections = Vec::new();
for line in plus_lines.iter() {
plus_line_sections.push(Painter::get_line_syntax_style_sections(
&line,
highlighter,
&config,
true,
));
}
(minus_line_sections, plus_line_sections)
}
pub fn get_line_syntax_style_sections(
line: &'a str,
highlighter: &mut HighlightLines,
config: &config::Config,
should_syntax_highlight: bool,
) -> Vec<(Style, &'a str)> {
if should_syntax_highlight && config.theme.is_some() {
highlighter.highlight(line, &config.syntax_set)
} else {
vec![(config.no_style, line)]
}
}
/// Set background styles to represent diff for minus and plus lines in buffer.
fn get_diff_style_sections<'b>(
minus_lines: &'b [String],
plus_lines: &'b [String],
config: &config::Config,
) -> (
Vec
|