From b1783c4e6ae2efa4c5f21de77e9313d130f4e8b2 Mon Sep 17 00:00:00 2001
From: Wilfred Hughes <me@wilfred.me.uk>
Date: Thu, 2 Oct 2025 01:36:41 +0100
Subject: [PATCH] Add comment clarifying . line number rendering rationale

---
 src/display/side_by_side.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/display/side_by_side.rs b/src/display/side_by_side.rs
index e1aa6d9e9..4027223bd 100644
--- a/src/display/side_by_side.rs
+++ b/src/display/side_by_side.rs
@@ -57,6 +57,13 @@ fn format_missing_line_num(
     let num_digits = prev_num.display().len();
     format!(
         "{:>width$} ",
+        // If there are further lines in this file, we want to use
+        // . (i.e. dot), but if we've already shown the last line we
+        // just render whitespace.
+        //
+        // We also want to show dots when we're rendering a
+        // continuation line, i.e. the content line is so long we need
+        // to wrap it.
         (if after_end { " " } else { "." }).repeat(num_digits),
         width = column_width - 1
     )