Add --diff-stat-align-width to control alignment of relativized paths

5 files changed, 19 insertions, 4 deletions

diff --git a/src/cli.rs b/src/cli.rs
index ca465454..4109269a 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -482,6 +482,11 @@ pub struct Opt {
     #[structopt(short = "w", long = "width")]
     pub width: Option<String>,
 
+    /// Width allocated for file paths in a diff stat section. If a relativized
+    /// file path exceeds this width then the diff stat will be misaligned.
+    #[structopt(long = "diff-stat-align-width", default_value = "48")]
+    pub diff_stat_align_width: usize,
+
     /// The number of spaces to replace tab characters with. Use --tabs=0 to pass tab characters
     /// through directly, but note that in that case delta will calculate line widths assuming tabs
     /// occupy one character's width on the screen: if your terminal renders tabs as more than than
diff --git a/src/config.rs b/src/config.rs
index c6719839..6d949dff 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -25,6 +25,7 @@ pub struct Config {
     pub color_only: bool,
     pub cwd_relative_to_repo_root: Option<String>,
     pub decorations_width: cli::Width,
+    pub diff_stat_align_width: usize,
     pub error_exit_code: i32,
     pub file_added_label: String,
     pub file_copied_label: String,
@@ -185,6 +186,7 @@ impl From<cli::Opt> for Config {
             color_only: opt.color_only,
             cwd_relative_to_repo_root: std::env::var("GIT_PREFIX").ok(),
             decorations_width: opt.computed.decorations_width,
+            diff_stat_align_width: opt.diff_stat_align_width,
             error_exit_code: 2, // Use 2 for error because diff uses 0 and 1 for non-error.
             file_added_label,
             file_copied_label,
diff --git a/src/delta.rs b/src/delta.rs
index 869bd4a4..608b89c9 100644
--- a/src/delta.rs
+++ b/src/delta.rs
@@ -231,9 +231,11 @@ impl<'a> StateMachine<'a> {
     fn handle_diff_stat_line(&mut self) -> std::io::Result<bool> {
         let mut handled_line = false;
         if let Some(cwd) = self.config.cwd_relative_to_repo_root.as_deref() {
-            if let Some(replacement_line) =
-                parse::relativize_path_in_diff_stat_line(&self.raw_line, cwd)
-            {
+            if let Some(replacement_line) = parse::relativize_path_in_diff_stat_line(
+                &self.raw_line,
+                cwd,
+                self.config.diff_stat_align_width,
+            ) {
                 self.painter.emit()?;
                 writeln!(self.painter.writer, "{}", replacement_line)?;
                 handled_line = true
diff --git a/src/options/set.rs b/src/options/set.rs
index 2d112f87..8373e86b 100644
--- a/src/options/set.rs
+++ b/src/options/set.rs
@@ -128,6 +128,7 @@ pub fn set_options(
             color_only,
             commit_decoration_style,
             commit_style,
+            diff_stat_align_width,
             file_added_label,
             file_copied_label,
             file_decoration_style,
diff --git a/src/parse.rs b/src/parse.rs
index 65ad72f1..a90323c3 100644
--- a/src/parse.rs
+++ b/src/parse.rs
@@ -85,6 +85,7 @@ lazy_static! {
 pub fn relativize_path_in_diff_stat_line(
     line: &str,
     cwd_relative_to_repo_root: &str,
+    diff_stat_align_width: usize,
 ) -> Option<String> {
     if let Some(caps) = DIFF_STAT_LINE_REGEX.captures(line) {
         let path_relative_to_repo_root = caps.get(1).unwrap().as_str();
@@ -93,7 +94,11 @@ pub fn relativize_path_in_diff_stat_line(
         {
             if let Some(relative_path) = relative_path.to_str() {
                 let suffix = caps.get(2).unwrap().as_str();
-                return Some(format!(" {:<30}{}", relative_path, suffix,));
+                let pad_width = diff_stat_align_width
+                    .checked_sub(relative_path.len())
+                    .unwrap_or(0);
+                let padding = " ".repeat(pad_width);
+                return Some(format!(" {}{}{}", relative_path, padding, suffix));
             }
         }
     }