From e7a4e68c5fb831b3e42c5af9cc83ebe1c00e1089 Mon Sep 17 00:00:00 2001
From: Shun-ichi Goto <shunichi.goto@gmail.com>
Date: Fri, 17 Apr 2026 17:14:56 +0900
Subject: [PATCH] fix: center diff change indicators and fix width calculation

- Center the +/- indicators horizontally in the diff gutter
- Use Math.Max(minus.Width, plus.Width) for accurate margin width
  instead of only measuring the '-' character
---
 src/Views/TextDiffView.axaml.cs | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/src/Views/TextDiffView.axaml.cs b/src/Views/TextDiffView.axaml.cs
index d3b602c3a..1e75811db 100644
--- a/src/Views/TextDiffView.axaml.cs
+++ b/src/Views/TextDiffView.axaml.cs
@@ -155,7 +155,10 @@ public override void Render(DrawingContext context)
                         }
 
                         if (indicator != null)
-                            context.DrawText(indicator, new Point(0, y - (indicator.Height * 0.5)));
+                        {
+                            var x = (Bounds.Width - indicator.Width) * 0.5;
+                            context.DrawText(indicator, new Point(x, y - (indicator.Height * 0.5)));
+                        }
                     }
                 }
             }
@@ -167,14 +170,21 @@ protected override Size MeasureOverride(Size availableSize)
                     return new Size(0, 0);
 
                 var typeface = TextView.CreateTypeface();
-                var test = new FormattedText(
+                var minus = new FormattedText(
                     "-",
                     CultureInfo.CurrentCulture,
                     FlowDirection.LeftToRight,
                     typeface,
                     presenter.FontSize,
                     Brushes.White);
-                return new Size(test.Width, 0);
+                var plus = new FormattedText(
+                    "+",
+                    CultureInfo.CurrentCulture,
+                    FlowDirection.LeftToRight,
+                    typeface,
+                    presenter.FontSize,
+                    Brushes.White);
+                return new Size(Math.Max(minus.Width, plus.Width), 0);
             }
 
             protected override void OnDataContextChanged(EventArgs e)