1 files changed, 45 insertions, 15 deletions

diff --git a/src/delta.rs b/src/delta.rs
index c42ba9f1..fca76ff8 100644
--- a/src/delta.rs
+++ b/src/delta.rs
@@ -18,13 +18,14 @@ use crate::style::{self, DecorationStyle};
 
 #[derive(Clone, Debug, PartialEq)]
 pub enum State {
-    CommitMeta,                // In commit metadata section
+    CommitMeta,                 // In commit metadata section
     FileMeta, // In diff metadata section, between (possible) commit metadata and first hunk
-    HunkHeader, // In hunk metadata line
+    HunkHeader(String, String), // In hunk metadata line (line, raw_line)
     HunkZero, // In hunk; unchanged line
     HunkMinus(Option<String>), // In hunk; removed line (raw_line)
     HunkPlus(Option<String>), // In hunk; added line (raw_line)
-    Submodule,
+    SubmoduleLog, // In a submodule section, with gitconfig diff.submodule = log
+    SubmoduleShort(String), // In a submodule section, with gitconfig diff.submodule = short
     Unknown,
 }
 
@@ -39,7 +40,7 @@ impl State {
     fn is_in_hunk(&self) -> bool {
         matches!(
             *self,
-            State::HunkHeader | State::HunkZero | State::HunkMinus(_) | State::HunkPlus(_)
+            State::HunkHeader(_, _) | State::HunkZero | State::HunkMinus(_) | State::HunkPlus(_)
         )
     }
 }
@@ -145,7 +146,13 @@ impl<'a> StateMachine<'a> {
             {
                 self.handle_additional_cases(State::FileMeta)?
             } else if line.starts_with("Submodule ") {
-                self.handle_additional_cases(State::Submodule)?
+                self.handle_additional_cases(State::SubmoduleLog)?
+            } else if (matches!(self.state, State::HunkHeader(_, _))
+                && line.starts_with("-Subproject commit "))
+                || (matches!(self.state, State::SubmoduleShort(_))
+                    && line.starts_with("+Subproject commit "))
+            {
+                self.handle_submodule_short_line()?
             } else if self.state.is_in_hunk() {
                 // A true hunk line should start with one of: '+', '-', ' '. However, handle_hunk_line
                 // handles all lines until the state transitions away from the hunk states.
@@ -415,14 +422,39 @@ impl<'a> StateMachine<'a> {
         Ok(handled_line)
     }
 
-    /// Emit the hunk header, with any requested decoration.
+    fn handle_submodule_short_line(&mut self) -> std::io::Result<bool> {
+        if let Some(commit) = parse::get_submodule_short_commit(&self.line) {
+            if let State::HunkHeader(_, _) = self.state {
+                self.state = State::SubmoduleShort(commit.to_owned());
+            } else if let State::SubmoduleShort(minus_commit) = &self.state {
+                self.painter.emit()?;
+                writeln!(
+                    self.painter.writer,
+                    "{} ⟶   {}",
+                    self.config
+                        .minus_style
+                        .paint(minus_commit.chars().take(7).collect::<String>()),
+                    self.config
+                        .plus_style
+                        .paint(commit.chars().take(7).collect::<String>()),
+                )?;
+            }
+        }
+        Ok(true)
+    }
+
     fn handle_hunk_header_line(&mut self) -> std::io::Result<bool> {
+        self.state = State::HunkHeader(self.line.clone(), self.raw_line.clone());
+        Ok(true)
+    }
+
+    /// Emit the hunk header, with any requested decoration.
+    fn emit_hunk_header_line(&mut self, line: &str, raw_line: &str) -> std::io::Result<bool> {
         self.painter.paint_buffered_minus_and_plus_lines();
-        self.state = State::HunkHeader;
         self.painter.set_highlighter();
         self.painter.emit()?;
 
-        let (code_fragment, line_numbers) = parse::parse_hunk_header(&self.line);
+        let (code_fragment, line_numbers) = parse::parse_hunk_header(line);
         if self.config.line_numbers {
             self.painter
                 .line_numbers_data
@@ -430,12 +462,7 @@ impl<'a> StateMachine<'a> {
         }
 
         if self.config.hunk_header_style.is_raw {
-            hunk_header::write_hunk_header_raw(
-                &mut self.painter,
-                &self.line,
-                &self.raw_line,
-                self.config,
-            )?;
+            hunk_header::write_hunk_header_raw(&mut self.painter, line, raw_line, self.config)?;
         } else if self.config.hunk_header_style.is_omitted {
             writeln!(self.painter.writer)?;
         } else {
@@ -449,7 +476,7 @@ impl<'a> StateMachine<'a> {
                 &code_fragment,
                 &line_numbers,
                 &mut self.painter,
-                &self.line,
+                line,
                 &self.plus_file,
                 self.config,
             )?;
@@ -473,6 +500,9 @@ impl<'a> StateMachine<'a> {
         {
             self.painter.paint_buffered_minus_and_plus_lines();
         }
+        if let State::HunkHeader(line, raw_line) = &self.state.clone() {
+            self.emit_hunk_header_line(line, raw_line)?;
+        }
         self.state = match self.line.chars().next() {
             Some('-') => {
                 if let State::HunkPlus(_) = self.state {