feature<Diff>: highlights differences for modified lines (both added and removed)

build.bat

@@ -6,7 +6,7 @@ cd src
 rmdir /s /q bin
 rmdir /s /q obj
 dotnet publish SourceGit_48.csproj --nologo -c Release -r win-x86 -o ..\publish\net48
-ilrepack /ndebug /out:..\publish\SourceGit.exe ..\publish\net48\SourceGit.exe ..\publish\net48\Newtonsoft.Json.dll
+ilrepack /ndebug /out:..\publish\SourceGit.exe ..\publish\net48\SourceGit.exe ..\publish\net48\Newtonsoft.Json.dll ..\publish\net48\DiffPlex.dll
 cd ..\publish
 ren SourceGit.exe SourceGit_48.exe
 rmdir /s /q net48

src/Commands/Diff.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Text.RegularExpressions;
 
 namespace SourceGit.Commands {
@@ -8,6 +9,8 @@ namespace SourceGit.Commands {
     public class Diff : Command {
         private static readonly Regex REG_INDICATOR = new Regex(@"^@@ \-(\d+),?\d* \+(\d+),?\d* @@");
         private Models.TextChanges changes = new Models.TextChanges();
+        private List<Models.TextChanges.Line> deleted = new List<Models.TextChanges.Line>();
+        private List<Models.TextChanges.Line> added = new List<Models.TextChanges.Line>();
         private int oldLine = 0;
         private int newLine = 0;
 
@@ -18,6 +21,7 @@ namespace SourceGit.Commands {
 
         public Models.TextChanges Result() {
             Exec();
+            ProcessChanges();
             if (changes.IsBinary) changes.Lines.Clear();
             return changes;
         }
@@ -37,6 +41,7 @@ namespace SourceGit.Commands {
                 changes.Lines.Add(new Models.TextChanges.Line(Models.TextChanges.LineMode.Indicator, line, "", ""));
             } else {
                 if (line.Length == 0) {
+                    ProcessChanges();
                     changes.Lines.Add(new Models.TextChanges.Line(Models.TextChanges.LineMode.Normal, "", $"{oldLine}", $"{newLine}"));
                     oldLine++;
                     newLine++;
@@ -45,12 +50,13 @@ namespace SourceGit.Commands {
 
                 var ch = line[0];
                 if (ch == '-') {
-                    changes.Lines.Add(new Models.TextChanges.Line(Models.TextChanges.LineMode.Deleted, line.Substring(1), $"{oldLine}", ""));
+                    deleted.Add(new Models.TextChanges.Line(Models.TextChanges.LineMode.Deleted, line.Substring(1), $"{oldLine}", ""));
                     oldLine++;
                 } else if (ch == '+') {
-                    changes.Lines.Add(new Models.TextChanges.Line(Models.TextChanges.LineMode.Added, line.Substring(1), "", $"{newLine}"));
+                    added.Add(new Models.TextChanges.Line(Models.TextChanges.LineMode.Added, line.Substring(1), "", $"{newLine}"));
                     newLine++;
                 } else if (ch != '\\') {
+                    ProcessChanges();
                     var match = REG_INDICATOR.Match(line);
                     if (match.Success) {
                         oldLine = int.Parse(match.Groups[1].Value);
@@ -64,5 +70,29 @@ namespace SourceGit.Commands {
                 }
             }
         }
+    
+        private void ProcessChanges() {
+            if (deleted.Count > 0) {
+                if (added.Count == deleted.Count) {
+                    for (int i = added.Count - 1; i >= 0; i--) {
+                        var left = deleted[i];
+                        var right = added[i];
+                        var result = DiffPlex.Differ.Instance.CreateCharacterDiffs(left.Content, right.Content, false, false);
+                        foreach (var block in result.DiffBlocks) {
+                            left.Highlights.Add(new Models.TextChanges.HighlightRange(block.DeleteStartA, block.DeleteCountA));
+                            right.Highlights.Add(new Models.TextChanges.HighlightRange(block.InsertStartB, block.InsertCountB));
+                        }
+                    }
+                }
+
+                changes.Lines.AddRange(deleted);
+                deleted.Clear();
+            }
+
+            if (added.Count > 0) {
+                changes.Lines.AddRange(added);
+                added.Clear();
+            }
+        }
     }
 }

src/Models/TextChanges.cs

@@ -14,11 +14,18 @@ namespace SourceGit.Models {
             Deleted,
         }
 
+        public class HighlightRange {
+            public int Start { get; set; }
+            public int Count { get; set; }
+            public HighlightRange(int p, int n) { Start = p; Count = n; }
+        }
+
         public class Line {
             public LineMode Mode = LineMode.Normal;
             public string Content = "";
             public string OldLine = "";
             public string NewLine = "";
+            public List<HighlightRange> Highlights = new List<HighlightRange>();
 
             public Line(LineMode mode, string content, string oldLine, string newLine) {
                 Mode = mode;

src/SourceGit.csproj

@@ -17,4 +17,7 @@
         <PackageRequireLicenseAcceptance>true</PackageRequireLicenseAcceptance>
         <SatelliteResourceLanguages>none</SatelliteResourceLanguages>
     </PropertyGroup>
+    <ItemGroup>
+      <PackageReference Include="DiffPlex" Version="1.7.0" />
+    </ItemGroup>
 </Project>

src/SourceGit_48.csproj

@@ -21,5 +21,6 @@
     </PropertyGroup>
     <ItemGroup>
       <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
+      <PackageReference Include="DiffPlex" Version="1.7.0" />
     </ItemGroup>
 </Project>

src/Views/Controls/HighlightableTextBlock.cs

@@ -0,0 +1,63 @@
+using System.Collections.Generic;
+using System.Windows;
+using System.Windows.Media;
+using System.Windows.Controls;
+using System.Windows.Documents;
+
+namespace SourceGit.Views.Controls {
+    /// <summary>
+    ///     支持部分高亮的文本组件
+    /// </summary>
+    public class HighlightableTextBlock : TextBlock {
+
+        public class Data {
+            public string Text { get; set; } = "";
+            public List<Models.TextChanges.HighlightRange> Highlights { get; set; } = new List<Models.TextChanges.HighlightRange>();
+            public Brush HighlightBrush { get; set; } = Brushes.Transparent;
+        }
+
+        public static readonly DependencyProperty ContentProperty = DependencyProperty.Register(
+            "Content", 
+            typeof(Data),
+            typeof(HighlightableTextBlock), 
+            new PropertyMetadata(null, OnContentChanged));
+
+        public Data Content {
+            get { return (Data)GetValue(ContentProperty); }
+            set { SetValue(ContentProperty, value); }
+        }
+
+        private static void OnContentChanged(DependencyObject d, DependencyPropertyChangedEventArgs e) {
+            var txt = d as HighlightableTextBlock;
+            if (txt == null) return;
+
+            txt.Inlines.Clear();
+            txt.Text = null;
+            if (txt.Content == null) return;
+
+            if (txt.Content.Highlights == null || txt.Content.Highlights.Count == 0) {
+                txt.Text = txt.Content.Text;
+                return;
+            }
+
+            var started = 0;
+            foreach (var highlight in txt.Content.Highlights) {
+                if (started < highlight.Start) {
+                    txt.Inlines.Add(new Run(txt.Content.Text.Substring(started, highlight.Start - started)));
+                }
+
+                txt.Inlines.Add(new TextBlock() {
+                    Background = txt.Content.HighlightBrush,
+                    LineHeight = txt.LineHeight,
+                    Text = txt.Content.Text.Substring(highlight.Start, highlight.Count),
+                });
+
+                started = highlight.Start + highlight.Count;
+            }
+
+            if (started < txt.Content.Text.Length) {
+                txt.Inlines.Add(new Run(txt.Content.Text.Substring(started)));
+            }
+        }
+    }
+}

src/Views/Widgets/DiffViewer.xaml.cs

@@ -19,6 +19,9 @@ namespace SourceGit.Views.Widgets {
         private static readonly Brush BG_ADDED = new SolidColorBrush(Color.FromArgb(60, 0, 255, 0));
         private static readonly Brush BG_DELETED = new SolidColorBrush(Color.FromArgb(60, 255, 0, 0));
         private static readonly Brush BG_NORMAL = Brushes.Transparent;
+        private static readonly Brush HL_ADDED = new SolidColorBrush(Color.FromArgb(100, 0, 255, 0));
+        private static readonly Brush HL_DELETED = new SolidColorBrush(Color.FromArgb(100, 255, 0, 0));
+        private static readonly Brush HL_NORMAL = Brushes.Transparent;
 
         public class Option {
             public string[] RevisionRange = new string[] { };
@@ -29,13 +32,13 @@ namespace SourceGit.Views.Widgets {
         }
 
         public class Block {
-            public string Content { get; set; }
             public Models.TextChanges.LineMode Mode { get; set; }
             public Brush BG { get; set; }
             public Brush FG { get; set; }
             public FontStyle Style { get; set; }
             public string OldLine { get; set; }
             public string NewLine { get; set; }
+            public Controls.HighlightableTextBlock.Data Data { get; set; } = new Controls.HighlightableTextBlock.Data();
 
             public bool IsContent {
                 get {
@@ -216,14 +219,15 @@ namespace SourceGit.Views.Widgets {
 
             foreach (var line in cachedTextChanges) {
                 var block = new Block();
-                block.Content = line.Content;
                 block.Mode = line.Mode;
                 block.BG = GetLineBackground(line);
                 block.FG = block.IsContent ? fgCommon : fgIndicator;
                 block.Style = block.IsContent ? FontStyles.Normal : FontStyles.Italic;
                 block.OldLine = line.OldLine;
                 block.NewLine = line.NewLine;
-
+                block.Data.Text = line.Content;
+                block.Data.HighlightBrush = GetLineHighlight(line);
+                block.Data.Highlights.AddRange(line.Highlights);
 
                 if (line.OldLine.Length > 0) lastOldLine = line.OldLine;
                 if (line.NewLine.Length > 0) lastNewLine = line.NewLine;
@@ -278,13 +282,15 @@ namespace SourceGit.Views.Widgets {
 
             foreach (var line in cachedTextChanges) {
                 var block = new Block();
-                block.Content = line.Content;
                 block.Mode = line.Mode;
                 block.BG = GetLineBackground(line);
                 block.FG = block.IsContent ? fgCommon : fgIndicator;
                 block.Style = block.IsContent ? FontStyles.Normal : FontStyles.Italic;
                 block.OldLine = line.OldLine;
                 block.NewLine = line.NewLine;
+                block.Data.Text = line.Content;
+                block.Data.HighlightBrush = GetLineHighlight(line);
+                block.Data.Highlights.AddRange(line.Highlights);
 
                 if (line.OldLine.Length > 0) lastOldLine = line.OldLine;
                 if (line.NewLine.Length > 0) lastNewLine = line.NewLine;
@@ -369,13 +375,23 @@ namespace SourceGit.Views.Widgets {
             }
         }
 
+        private Brush GetLineHighlight(Models.TextChanges.Line line) {
+            switch (line.Mode) {
+            case Models.TextChanges.LineMode.Added:
+                return HL_ADDED;
+            case Models.TextChanges.LineMode.Deleted:
+                return HL_DELETED;
+            default:
+                return HL_NORMAL;
+            }
+        }
+
         private void FillEmptyLines(List<Block> old, List<Block> cur) {
             if (old.Count < cur.Count) {
                 int diff = cur.Count - old.Count;
 
                 for (int i = 0; i < diff; i++) {
                     var empty = new Block();
-                    empty.Content = "";
                     empty.Mode = Models.TextChanges.LineMode.None;
                     empty.BG = BG_EMPTY;
                     empty.FG = Brushes.Transparent;
@@ -389,7 +405,6 @@ namespace SourceGit.Views.Widgets {
 
                 for (int i = 0; i < diff; i++) {
                     var empty = new Block();
-                    empty.Content = "";
                     empty.Mode = Models.TextChanges.LineMode.None;
                     empty.BG = BG_EMPTY;
                     empty.FG = Brushes.Transparent;
@@ -432,7 +447,7 @@ namespace SourceGit.Views.Widgets {
                     if (block == null) continue;
                     if (!block.IsContent) continue;
 
-                    builder.Append(block.Content);
+                    builder.Append(block.Data.Text);
                     builder.AppendLine();
                 }
 
@@ -447,27 +462,21 @@ namespace SourceGit.Views.Widgets {
                 grid.Columns.Add(colLineNumber);
             }
 
-            var borderContent = new FrameworkElementFactory(typeof(Border));
+            var line = new FrameworkElementFactory(typeof(Controls.HighlightableTextBlock));
-            borderContent.SetBinding(Border.BackgroundProperty, new Binding("BG"));
+            line.SetBinding(Controls.HighlightableTextBlock.ContentProperty, new Binding("Data"));
-
+            line.SetBinding(TextBlock.BackgroundProperty, new Binding("BG"));
-            var textContent = new FrameworkElementFactory(typeof(TextBlock));
+            line.SetBinding(TextBlock.ForegroundProperty, new Binding("FG"));
-            textContent.SetBinding(TextBlock.TextProperty, new Binding("Content"));
+            line.SetBinding(TextBlock.FontStyleProperty, new Binding("Style"));
-            textContent.SetBinding(TextBlock.ForegroundProperty, new Binding("FG"));
+            line.SetValue(TextBlock.FontSizeProperty, new FontSizeConverter().ConvertFrom("9pt"));
-            textContent.SetBinding(TextBlock.FontStyleProperty, new Binding("Style"));
+            line.SetValue(TextBlock.MarginProperty, new Thickness(0));
-            textContent.SetValue(TextBlock.BackgroundProperty, Brushes.Transparent);
+            line.SetValue(TextBlock.PaddingProperty, new Thickness(4, 0, 0, 0));
-            textContent.SetValue(TextBlock.FontSizeProperty, new FontSizeConverter().ConvertFrom("9pt"));
+            line.SetValue(TextBlock.LineHeightProperty, 16.0);
-            textContent.SetValue(TextBlock.MarginProperty, new Thickness(0));
+            line.SetValue(TextOptions.TextFormattingModeProperty, TextFormattingMode.Display);
-            textContent.SetValue(TextBlock.PaddingProperty, new Thickness(4, 0, 0, 0));
+            line.SetValue(TextOptions.TextRenderingModeProperty, TextRenderingMode.ClearType);
-            textContent.SetValue(TextOptions.TextFormattingModeProperty, TextFormattingMode.Display);
-            textContent.SetValue(TextOptions.TextRenderingModeProperty, TextRenderingMode.ClearType);
-
-            var visualTree = new FrameworkElementFactory(typeof(Grid));
-            visualTree.AppendChild(borderContent);
-            visualTree.AppendChild(textContent);
 
             var colContent = new DataGridTemplateColumn();
             colContent.CellTemplate = new DataTemplate();
-            colContent.CellTemplate.VisualTree = visualTree;
+            colContent.CellTemplate.VisualTree = line;
             colContent.Width = DataGridLength.SizeToCells;
             grid.Columns.Add(colContent);
 
@@ -567,7 +576,7 @@ namespace SourceGit.Views.Widgets {
                     if (block == null) continue;
                     if (!block.IsContent) continue;
 
-                    builder.Append(block.Content);
+                    builder.Append(block.Data.Text);
                     builder.AppendLine();
                 }