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Diffstat (limited to 'src/handlers/blame.rs')
-rw-r--r-- | src/handlers/blame.rs | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/src/handlers/blame.rs b/src/handlers/blame.rs new file mode 100644 index 00000000..d7486303 --- /dev/null +++ b/src/handlers/blame.rs @@ -0,0 +1,181 @@ +use chrono::{DateTime, FixedOffset}; +use lazy_static::lazy_static; +use regex::Regex; + +use crate::color; +use crate::config; +use crate::delta::{self, State, StateMachine}; +use crate::format; +use crate::style::Style; + +impl<'a> StateMachine<'a> { + /// If this is a line of git blame output then render it accordingly. If + /// this is the first blame line, then set the syntax-highlighter language + /// according to delta.default-language. + pub fn handle_blame_line(&mut self) -> std::io::Result<bool> { + let mut handled_line = false; + self.painter.emit()?; + if matches!(self.state, State::Unknown | State::Blame(_)) { + if let Some(blame) = + parse_git_blame_line(&self.line, &self.config.blame_timestamp_format) + { + // Determine color for this line + let color = if let Some(color) = self.blame_commit_colors.get(blame.commit) { + color + } else { + let n_commits = self.blame_commit_colors.len(); + let n_colors = self.config.blame_palette.len(); + let new_color = &self.config.blame_palette[(n_commits + 1) % n_colors]; + self.blame_commit_colors + .insert(blame.commit.to_owned(), new_color.to_owned()); + new_color + }; + let mut style = Style::from_colors(None, color::parse_color(color, true)); + style.is_syntax_highlighted = true; + + // Construct commit metadata, paint, and emit + let format_data = format::parse_line_number_format( + &self.config.blame_format, + &*BLAME_PLACEHOLDER_REGEX, + ); + write!( + self.painter.writer, + "{}", + style.paint(format_blame_metadata(&format_data, &blame, self.config)) + )?; + + // Emit syntax-highlighted code + if matches!(self.state, State::Unknown) { + if let Some(lang) = self.config.default_language.as_ref() { + self.painter.set_syntax(Some(lang)); + self.painter.set_highlighter(); + } + self.state = State::Blame(blame.commit.to_owned()); + } + self.painter.syntax_highlight_and_paint_line( + blame.code, + style, + self.state.clone(), + true, + ); + handled_line = true + } + } + Ok(handled_line) + } +} + +#[derive(Debug)] +pub struct BlameLine<'a> { + pub commit: &'a str, + pub author: &'a str, + pub time: DateTime<FixedOffset>, + pub line_number: usize, + pub code: &'a str, +} + +// E.g. +//ea82f2d0 (Dan Davison 2021-08-22 18:20:19 -0700 120) let mut handled_line = self.handle_commit_meta_header_line()? + +lazy_static! { + static ref BLAME_LINE_REGEX: Regex = Regex::new( + r"(?x) +^ +( + [0-9a-f]{8} # commit hash +) +[\ ] +\( # open ( +( + [^\ ].*[^\ ] # author name +) +[\ ]+ +( # timestamp + [0-9]{4}-[0-9]{2}-[0-9]{2}\ [0-9]{2}:[0-9]{2}:[0-9]{2}\ [-+][0-9]{4} +) +[\ ]+ +( + [0-9]+ # line number +) +\) # close ) +( + .* # code, with leading space +) +$ +" + ) + .unwrap(); +} + +pub fn parse_git_blame_line<'a>(line: &'a str, timestamp_format: &str) -> Option<BlameLine<'a>> { + if let Some(caps) = BLAME_LINE_REGEX.captures(line) { + let commit = caps.get(1).unwrap().as_str(); + let author = caps.get(2).unwrap().as_str(); + let timestamp = caps.get(3).unwrap().as_str(); + if let Ok(time) = DateTime::parse_from_str(timestamp, timestamp_format) { + let line_number_str = caps.get(4).unwrap().as_str(); + if let Ok(line_number) = line_number_str.parse::<usize>() { + let code = caps.get(5).unwrap().as_str(); + Some(BlameLine { + commit, + author, + time, + line_number, + code, + }) + } else { + None + } + } else { + None + } + } else { + None + } +} + +lazy_static! { + pub static ref BLAME_PLACEHOLDER_REGEX: Regex = + format::make_placeholder_regex(&["timestamp", "author", "commit"]); +} + +pub fn format_blame_metadata( + format_data: &[format::FormatStringPlaceholderData], + blame: &BlameLine, + config: &config::Config, +) -> String { + let mut s = String::new(); + let mut suffix = ""; + for placeholder in format_data { + s.push_str(placeholder.prefix); + + let alignment_spec = placeholder.alignment_spec.unwrap_or("<"); + let width = placeholder.width.unwrap_or(15); + + let pad = |s| format::pad(s, width, alignment_spec); + match placeholder.placeholder { + Some("timestamp") => s.push_str(&pad( + &chrono_humanize::HumanTime::from(blame.time).to_string() + )), + Some("author") => s.push_str(&pad(blame.author)), + Some("commit") => s.push_str(&pad(&delta::format_raw_line(blame.commit, config))), + None => {} + Some(_) => unreachable!(), + } + suffix = placeholder.suffix; + } + s.push_str(suffix); + s +} + +#[test] +fn test_blame_line_regex() { + for line in &[ + "ea82f2d0 (Dan Davison 2021-08-22 18:20:19 -0700 120) let mut handled_line = self.handle_commit_meta_header_line()?", + "b2257cfa (Dan Davison 2020-07-18 15:34:43 -0400 1) use std::borrow::Cow;" + ] { + let caps = BLAME_LINE_REGEX.captures(line); + assert!(caps.is_some()); + assert!(parse_git_blame_line(line, "%Y-%m-%d %H:%M:%S %z").is_some()); + } +} |