Format files and commits as OSC 8 hyperlinks

Closes #257

src/cli.rs

@@ -341,6 +341,31 @@ pub struct Opt {
     /// (overline), or the combination 'ul ol'.
     pub file_decoration_style: String,
 
+    #[structopt(long = "hyperlinks")]
+    /// Render commit hashes, file names, and line numbers as hyperlinks, according to the
+    /// hyperlink spec for terminal emulators:
+    /// https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda. By default, file names
+    /// and line numbers link to the local file using a file URL, whereas commit hashes link to the
+    /// commit in GitHub, if the remote repository is hosted by GitHub. See
+    /// --hyperlinks-file-link-format for full control over the file URLs emitted. Hyperlinks are
+    /// supported by several common terminal emulators. However, they are not yet supported by
+    /// less, so they will not work in delta unless you install a patched fork of less (see
+    /// https://github.com/dandavison/less). If you use tmux, then you will also need a patched
+    /// fork of tmux (see https://github.com/dandavison/tmux).
+    pub hyperlinks: bool,
+
+    /// Format string for file hyperlinks. The placeholders "{path}" and "{line}" will be replaced
+    /// by the absolute file path and the line number, respectively. The default value of this
+    /// option creates hyperlinks using standard file URLs; your operating system should open these
+    /// in the application registered for that file type. However, these do not make use of the
+    /// line number. In order for the link to open the file at the correct line number, you could
+    /// use a custom URL format such as "file-line://{path}:{line_number}" and register an
+    /// application to handle the custom "file-line" URL scheme by opening the file in your
+    /// editor/IDE at the indicated line number. See https://github.com/dandavison/open-in-editor
+    /// for an example.
+    #[structopt(long = "hyperlinks-file-link-format", default_value = "file://{path}")]
+    pub hyperlinks_file_link_format: String,
+
     #[structopt(long = "hunk-header-style", default_value = "syntax")]
     /// Style (foreground, background, attributes) for the hunk-header. See STYLES section. The
     /// style 'omit' can be used to remove the hunk header section from the output.

src/config.rs

@@ -30,6 +30,8 @@ pub struct Config {
     pub git_config_entries: HashMap<String, GitConfigEntry>,
     pub keep_plus_minus_markers: bool,
     pub hunk_header_style: Style,
+    pub hyperlinks: bool,
+    pub hyperlinks_file_link_format: String,
     pub max_buffered_lines: usize,
     pub max_line_distance: f64,
     pub max_line_distance_for_naively_paired_lines: f64,
@@ -140,6 +142,8 @@ impl From<cli::Opt> for Config {
             git_config_entries: opt.git_config_entries,
             keep_plus_minus_markers: opt.keep_plus_minus_markers,
             hunk_header_style,
+            hyperlinks: opt.hyperlinks,
+            hyperlinks_file_link_format: opt.hyperlinks_file_link_format,
             max_buffered_lines: 32,
             max_line_distance: opt.max_line_distance,
             max_line_distance_for_naively_paired_lines,

src/delta.rs

@@ -1,3 +1,4 @@
+use std::borrow::Cow;
 use std::io::BufRead;
 use std::io::Write;
 
@@ -7,6 +8,8 @@ use unicode_segmentation::UnicodeSegmentation;
 
 use crate::config::Config;
 use crate::draw;
+use crate::features;
+use crate::format;
 use crate::paint::Painter;
 use crate::parse;
 use crate::style::DecorationStyle;
@@ -60,7 +63,7 @@ where
 {
     let mut painter = Painter::new(writer, config);
     let mut minus_file = "".to_string();
-    let mut plus_file;
+    let mut plus_file = "".to_string();
     let mut state = State::Unknown;
     let mut source = Source::Unknown;
 
@@ -115,7 +118,7 @@ where
             painter.set_highlighter();
             if should_handle(&state, config) {
                 painter.emit()?;
-                handle_hunk_header_line(&mut painter, &line, &raw_line, config)?;
+                handle_hunk_header_line(&mut painter, &line, &raw_line, &plus_file, config)?;
                 continue;
             }
         } else if source == Source::DiffUnified && line.starts_with("Only in ")
@@ -155,7 +158,11 @@ where
             continue;
         } else {
             painter.emit()?;
-            writeln!(painter.writer, "{}", raw_line)?;
+            writeln!(
+                painter.writer,
+                "{}",
+                format::format_raw_line(&raw_line, config)
+            )?;
         }
     }
 
@@ -240,10 +247,25 @@ fn handle_commit_meta_header_line(
             draw::write_no_decoration
         }
     };
+    let (formatted_line, formatted_raw_line) = if config.hyperlinks {
+        (
+            Cow::from(
+                features::hyperlinks::format_commit_line_with_osc8_commit_hyperlink(line, config),
+            ),
+            Cow::from(
+                features::hyperlinks::format_commit_line_with_osc8_commit_hyperlink(
+                    raw_line, config,
+                ),
+            ),
+        )
+    } else {
+        (Cow::from(line), Cow::from(raw_line))
+    };
+
     draw_fn(
         painter.writer,
-        &format!("{}{}", line, if pad { " " } else { "" }),
-        &format!("{}{}", raw_line, if pad { " " } else { "" }),
+        &format!("{}{}", formatted_line, if pad { " " } else { "" }),
+        &format!("{}{}", formatted_raw_line, if pad { " " } else { "" }),
         &config.decorations_width,
         config.commit_style,
         decoration_ansi_term_style,
@@ -332,6 +354,7 @@ fn handle_hunk_header_line(
     painter: &mut Painter,
     line: &str,
     raw_line: &str,
+    plus_file: &str,
     config: &Config,
 ) -> std::io::Result<()> {
     if config.hunk_header_style.is_omitted {
@@ -425,16 +448,28 @@ fn handle_hunk_header_line(
     };
     // Emit a single line number, or prepare for full line-numbering
     if config.line_numbers {
-        painter.line_numbers_data.initialize_hunk(line_numbers);
+        painter
+            .line_numbers_data
+            .initialize_hunk(line_numbers, plus_file.to_string());
     } else {
         let plus_line_number = line_numbers[line_numbers.len() - 1].0;
+        let formatted_plus_line_number = if config.hyperlinks {
+            features::hyperlinks::format_osc8_file_hyperlink(
+                plus_file,
+                Some(plus_line_number),
+                &format!("{}", plus_line_number),
+                config,
+            )
+        } else {
+            Cow::from(format!("{}", plus_line_number))
+        };
         match config.hunk_header_style.decoration_ansi_term_style() {
             Some(style) => writeln!(
                 painter.writer,
                 "{}",
-                style.paint(format!("{}", plus_line_number))
+                style.paint(formatted_plus_line_number)
             )?,
-            None => writeln!(painter.writer, "{}", plus_line_number)?,
+            None => writeln!(painter.writer, "{}", formatted_plus_line_number)?,
         }
     }
     Ok(())

src/features/hyperlinks.rs

@@ -0,0 +1,88 @@
+use std::borrow::Cow;
+
+use lazy_static::lazy_static;
+use regex::{Captures, Regex};
+
+use crate::config::Config;
+use crate::features::OptionValueFunction;
+use crate::git_config_entry::{GitConfigEntry, GitRemoteRepo};
+
+pub fn make_feature() -> Vec<(String, OptionValueFunction)> {
+    builtin_feature!([
+        (
+            "hyperlinks",
+            bool,
+            None,
+            _opt => true
+        )
+    ])
+}
+
+pub fn format_commit_line_with_osc8_commit_hyperlink<'a>(
+    line: &'a str,
+    config: &Config,
+) -> Cow<'a, str> {
+    if let Some(GitConfigEntry::GitRemote(GitRemoteRepo::GitHubRepo(repo))) =
+        config.git_config_entries.get("remote.origin.url")
+    {
+        COMMIT_LINE_REGEX.replace(line, |captures: &Captures| {
+            format_commit_line_captures_with_osc8_commit_hyperlink(captures, repo)
+        })
+    } else {
+        Cow::from(line)
+    }
+}
+
+/// Create a file hyperlink to `path`, displaying `text`.
+pub fn format_osc8_file_hyperlink<'a>(
+    relative_path: &'a str,
+    line_number: Option<usize>,
+    text: &str,
+    config: &Config,
+) -> Cow<'a, str> {
+    if let Some(GitConfigEntry::Path(workdir)) = config.git_config_entries.get("delta.__workdir__")
+    {
+        let absolute_path = workdir.join(relative_path);
+        let mut url = config
+            .hyperlinks_file_link_format
+            .replace("{path}", &absolute_path.to_string_lossy());
+        if let Some(n) = line_number {
+            url = url.replace("{line}", &format!("{}", n))
+        } else {
+            url = url.replace("{line}", "")
+        };
+        Cow::from(format!(
+            "{osc}8;;{url}{st}{text}{osc}8;;{st}",
+            url = url,
+            text = text,
+            osc = "\x1b]",
+            st = "\x1b\\"
+        ))
+    } else {
+        Cow::from(relative_path)
+    }
+}
+
+lazy_static! {
+    static ref COMMIT_LINE_REGEX: Regex = Regex::new("(.* )([0-9a-f]{40})(.*)").unwrap();
+}
+
+fn format_commit_line_captures_with_osc8_commit_hyperlink<'a, 'b>(
+    captures: &'a Captures,
+    github_repo: &'b str,
+) -> String {
+    let commit = captures.get(2).unwrap().as_str();
+    format!(
+        "{prefix}{osc}8;;{url}{st}{commit}{osc}8;;{st}{suffix}",
+        url = format_github_commit_url(commit, github_repo),
+        commit = commit,
+        prefix = captures.get(1).unwrap().as_str(),
+        suffix = captures.get(3).unwrap().as_str(),
+        osc = "\x1b]",
+        st = "\x1b\\"
+    )
+}
+
+fn format_github_commit_url(commit: &str, github_repo: &str) -> String {
+    format!("https://github.com/{}/commit/{}", github_repo, commit)
+}

src/features/line_numbers.rs

@@ -6,6 +6,7 @@ use regex::Regex;
 
 use crate::config;
 use crate::delta::State;
+use crate::features::hyperlinks;
 use crate::features::side_by_side;
 use crate::features::OptionValueFunction;
 use crate::style::Style;
@@ -112,6 +113,8 @@ pub fn format_and_paint_line_numbers<'a>(
             line_numbers_data.hunk_max_line_number_width,
             &minus_style,
             &plus_style,
+            &line_numbers_data.plus_file,
+            config,
         ));
     }
 
@@ -124,6 +127,8 @@ pub fn format_and_paint_line_numbers<'a>(
             line_numbers_data.hunk_max_line_number_width,
             &minus_style,
             &plus_style,
+            &line_numbers_data.plus_file,
+            config,
         ));
     }
     formatted_numbers
@@ -155,6 +160,7 @@ pub struct LineNumbersData<'a> {
     pub hunk_minus_line_number: usize,
     pub hunk_plus_line_number: usize,
     pub hunk_max_line_number_width: usize,
+    pub plus_file: String,
 }
 
 // Although it's probably unusual, a single format string can contain multiple placeholders. E.g.
@@ -178,18 +184,20 @@ impl<'a> LineNumbersData<'a> {
             hunk_minus_line_number: 0,
             hunk_plus_line_number: 0,
             hunk_max_line_number_width: 0,
+            plus_file: "".to_string(),
         }
     }
 
     /// Initialize line number data for a hunk.
-    pub fn initialize_hunk(&mut self, line_numbers: Vec<(usize, usize)>) {
+    pub fn initialize_hunk(&mut self, line_numbers: Vec<(usize, usize)>, plus_file: String) {
         // Typically, line_numbers has length 2: an entry for the minus file, and one for the plus
         // file. In the case of merge commits, it may be longer.
         self.hunk_minus_line_number = line_numbers[0].0;
         self.hunk_plus_line_number = line_numbers[line_numbers.len() - 1].0;
         let hunk_max_line_number = line_numbers.iter().map(|(n, d)| n + d).max().unwrap();
         self.hunk_max_line_number_width =
             1 + (hunk_max_line_number as f64).log10().floor() as usize;
+        self.plus_file = plus_file;
     }
 }
 
@@ -233,6 +241,8 @@ fn format_and_paint_line_number_field<'a>(
     min_field_width: usize,
     minus_number_style: &Style,
     plus_number_style: &Style,
+    plus_file: &str,
+    config: &config::Config,
 ) -> Vec<ansi_term::ANSIGenericString<'a, str>> {
     let mut ansi_strings = Vec::new();
     let mut suffix = "";
@@ -251,11 +261,15 @@ fn format_and_paint_line_number_field<'a>(
                 minus_number,
                 alignment_spec,
                 width,
+                None,
+                config,
             ))),
             Some("np") => ansi_strings.push(plus_number_style.paint(format_line_number(
                 plus_number,
                 alignment_spec,
                 width,
+                Some(plus_file),
+                config,
             ))),
             None => {}
             Some(_) => unreachable!(),
@@ -267,15 +281,29 @@ fn format_and_paint_line_number_field<'a>(
 }
 
 /// Return line number formatted according to `alignment` and `width`.
-fn format_line_number(line_number: Option<usize>, alignment: &str, width: usize) -> String {
-    let n = line_number
-        .map(|n| format!("{}", n))
-        .unwrap_or_else(|| "".to_string());
-    match alignment {
+fn format_line_number(
+    line_number: Option<usize>,
+    alignment: &str,
+    width: usize,
+    plus_file: Option<&str>,
+    config: &config::Config,
+) -> String {
+    let format_n = |n| match alignment {
         "<" => format!("{0:<1$}", n, width),
         "^" => format!("{0:^1$}", n, width),
         ">" => format!("{0:>1$}", n, width),
         _ => unreachable!(),
+    };
+    match (line_number, config.hyperlinks, plus_file) {
+        (None, _, _) => format_n(""),
+        (Some(n), true, Some(file)) => hyperlinks::format_osc8_file_hyperlink(
+            file,
+            line_number,
+            &format_n(&n.to_string()),
+            config,
+        )
+        .to_string(),
+        (Some(n), _, _) => format_n(&n.to_string()),
     }
 }
 

src/features/mod.rs

@@ -38,6 +38,10 @@ pub fn make_builtin_features() -> HashMap<String, BuiltinFeature> {
             "diff-so-fancy".to_string(),
             diff_so_fancy::make_feature().into_iter().collect(),
         ),
+        (
+            "hyperlinks".to_string(),
+            hyperlinks::make_feature().into_iter().collect(),
+        ),
         (
             "line-numbers".to_string(),
             line_numbers::make_feature().into_iter().collect(),
@@ -81,6 +85,7 @@ macro_rules! builtin_feature {
 pub mod color_only;
 pub mod diff_highlight;
 pub mod diff_so_fancy;
+pub mod hyperlinks;
 pub mod line_numbers;
 pub mod navigate;
 pub mod raw;