feature: add context menu for changes in Views.CommitDetail and Views.RevisionCompare to diff with external merge tool (#53)

src/Resources/Locales/en_US.axaml

@@ -137,8 +137,9 @@
   <x:String x:Key="Text.Diff.Prev" xml:space="preserve">Previous Difference</x:String>
   <x:String x:Key="Text.Diff.SideBySide" xml:space="preserve">Side-By-Side Diff</x:String>
   <x:String x:Key="Text.Diff.SyntaxHighlight" xml:space="preserve">Syntax Highlighting</x:String>
-  <x:String x:Key="Text.Diff.UseMerger" xml:space="preserve">Open With Merge Tool</x:String>
+  <x:String x:Key="Text.Diff.UseMerger" xml:space="preserve">Open In Merge Tool</x:String>
   <x:String x:Key="Text.Diff.Welcome" xml:space="preserve">SELECT FILE TO VIEW CHANGES</x:String>
+  <x:String x:Key="Text.DiffWithMerger" xml:space="preserve">Open In Merge Tool</x:String>
   <x:String x:Key="Text.Discard" xml:space="preserve">Discard Changes</x:String>
   <x:String x:Key="Text.Discard.All" xml:space="preserve">All local changes in working copy.</x:String>
   <x:String x:Key="Text.Discard.Changes" xml:space="preserve">Changes :</x:String>

src/Resources/Locales/zh_CN.axaml

@@ -139,6 +139,7 @@
   <x:String x:Key="Text.Diff.SyntaxHighlight" xml:space="preserve">语法高亮</x:String>
   <x:String x:Key="Text.Diff.UseMerger" xml:space="preserve">使用外部合并工具查看</x:String>
   <x:String x:Key="Text.Diff.Welcome" xml:space="preserve">请选择需要对比的文件</x:String>
+  <x:String x:Key="Text.DiffWithMerger" xml:space="preserve">使用外部比对工具查看</x:String>
   <x:String x:Key="Text.Discard" xml:space="preserve">放弃更改确认</x:String>
   <x:String x:Key="Text.Discard.All" xml:space="preserve">所有本地址未提交的修改。</x:String>
   <x:String x:Key="Text.Discard.Changes" xml:space="preserve">需要放弃的变更 ：</x:String>

src/ViewModels/CommitDetail.cs

@@ -8,6 +8,7 @@ using Avalonia.Platform.Storage;
 using Avalonia.Threading;
 
 using CommunityToolkit.Mvvm.ComponentModel;
+using Microsoft.VisualBasic.FileIO;
 
 namespace SourceGit.ViewModels
 {
@@ -195,6 +196,28 @@ namespace SourceGit.ViewModels
         {
             var menu = new ContextMenu();
 
+            var diffWithMerger = new MenuItem();
+            diffWithMerger.Header = App.Text("DiffWithMerger");
+            diffWithMerger.Icon = App.CreateMenuIcon("Icons.Diff");
+            diffWithMerger.Click += (_, ev) =>
+            {
+                var opt = new Models.DiffOption(_commit, change);
+                var type = Preference.Instance.ExternalMergeToolType;
+                var exec = Preference.Instance.ExternalMergeToolPath;
+
+                var tool = Models.ExternalMergeTools.Supported.Find(x => x.Type == type);
+                if (tool == null || !File.Exists(exec))
+                {
+                    App.RaiseException(_repo, "Invalid merge tool in preference setting!");
+                    return;
+                }
+
+                var args = tool.Type != 0 ? tool.DiffCmd : Preference.Instance.ExternalMergeToolDiffCmd;
+                Task.Run(() => Commands.MergeTool.OpenForDiff(_repo, exec, args, opt));
+                ev.Handled = true;
+            };
+            menu.Items.Add(diffWithMerger);
+
             if (change.Index != Models.ChangeState.Deleted)
             {
                 var history = new MenuItem();
@@ -228,9 +251,11 @@ namespace SourceGit.ViewModels
                     ev.Handled = true;
                 };
 
+                menu.Items.Add(new MenuItem { Header = "-" });
                 menu.Items.Add(history);
                 menu.Items.Add(blame);
                 menu.Items.Add(explore);
+                menu.Items.Add(new MenuItem { Header = "-" });
             }            
 
             var copyPath = new MenuItem();
@@ -241,8 +266,8 @@ namespace SourceGit.ViewModels
                 App.CopyText(change.Path);
                 ev.Handled = true;
             };
-
             menu.Items.Add(copyPath);
+
             return menu;
         }
 

src/ViewModels/DiffContext.cs

@@ -147,7 +147,7 @@ namespace SourceGit.ViewModels
             });
         }
 
-        public async void OpenExternalMergeTool()
+        public void OpenExternalMergeTool()
         {
             var type = Preference.Instance.ExternalMergeToolType;
             var exec = Preference.Instance.ExternalMergeToolPath;
@@ -160,7 +160,7 @@ namespace SourceGit.ViewModels
             }
 
             var args = tool.Type != 0 ? tool.DiffCmd : Preference.Instance.ExternalMergeToolDiffCmd;
-            await Task.Run(() => Commands.MergeTool.OpenForDiff(_repo, exec, args, _option));
+            Task.Run(() => Commands.MergeTool.OpenForDiff(_repo, exec, args, _option));
         }
 
         private static readonly HashSet<string> IMG_EXTS = new HashSet<string>()

src/ViewModels/RevisionCompare.cs

@@ -157,33 +157,46 @@ namespace SourceGit.ViewModels
         {
             var menu = new ContextMenu();
 
+            var diffWithMerger = new MenuItem();
+            diffWithMerger.Header = App.Text("DiffWithMerger");
+            diffWithMerger.Icon = App.CreateMenuIcon("Icons.Diff");
+            diffWithMerger.Click += (_, ev) =>
+            {
+                var opt = new Models.DiffOption(StartPoint.SHA, EndPoint.SHA, change);
+                var type = Preference.Instance.ExternalMergeToolType;
+                var exec = Preference.Instance.ExternalMergeToolPath;
+
+                var tool = Models.ExternalMergeTools.Supported.Find(x => x.Type == type);
+                if (tool == null || !File.Exists(exec))
+                {
+                    App.RaiseException(_repo, "Invalid merge tool in preference setting!");
+                    return;
+                }
+
+                var args = tool.Type != 0 ? tool.DiffCmd : Preference.Instance.ExternalMergeToolDiffCmd;
+                Task.Run(() => Commands.MergeTool.OpenForDiff(_repo, exec, args, opt));
+                ev.Handled = true;
+            };
+            menu.Items.Add(diffWithMerger);
+
             if (change.Index != Models.ChangeState.Deleted)
             {
-                var history = new MenuItem();
-                history.Header = App.Text("FileHistory");
-                history.Click += (_, ev) =>
-                {
-                    var window = new Views.FileHistories() { DataContext = new FileHistories(_repo, change.Path) };
-                    window.Show();
-                    ev.Handled = true;
-                };
-
                 var full = Path.GetFullPath(Path.Combine(_repo, change.Path));
                 var explore = new MenuItem();
                 explore.Header = App.Text("RevealFile");
+                explore.Icon = App.CreateMenuIcon("Icons.Folder.Open");
                 explore.IsEnabled = File.Exists(full);
                 explore.Click += (_, ev) =>
                 {
                     Native.OS.OpenInFileManager(full, true);
                     ev.Handled = true;
                 };
-
-                menu.Items.Add(history);
                 menu.Items.Add(explore);
             }
 
             var copyPath = new MenuItem();
             copyPath.Header = App.Text("CopyPath");
+            copyPath.Icon = App.CreateMenuIcon("Icons.Copy");
             copyPath.Click += (_, ev) =>
             {
                 App.CopyText(change.Path);