enhance: only store subject in commits.

It has several advantages:

* reduce the memory costed by histories
* higher performance while parsing commits
* no need to calculate subject every time, which is invoked most frequently to render histories

src/Commands/QueryCommitFullMessage.cs

@@ -0,0 +1,19 @@
+namespace SourceGit.Commands
+{
+    public class QueryCommitFullMessage : Command
+    {
+        public QueryCommitFullMessage(string repo, string sha)
+        {
+            WorkingDirectory = repo;
+            Context = repo;
+            Args = $"show --no-show-signature --pretty=format:%B -s {sha}";
+        }
+
+        public string Result()
+        {
+            var rs = ReadToEnd();
+            if (rs.IsSuccess) return rs.StdOut.TrimEnd();
+            return string.Empty;
+        }
+    }
+}

src/Commands/QueryCommits.cs

@@ -7,11 +7,9 @@ namespace SourceGit.Commands
     {
         public QueryCommits(string repo, string limits, bool needFindHead = true)
         {
-            _endOfBodyToken = $"----- END OF BODY {Guid.NewGuid()} -----";
-
             WorkingDirectory = repo;
             Context = repo;
-            Args = $"log --date-order --no-show-signature --decorate=full --pretty=format:\"%H%n%P%n%D%n%aN±%aE%n%at%n%cN±%cE%n%ct%n%B%n{_endOfBodyToken}\" " + limits;
+            Args = $"log --date-order --no-show-signature --decorate=full --pretty=format:%H%n%P%n%D%n%aN±%aE%n%at%n%cN±%cE%n%ct%n%s " + limits;
             _findFirstMerged = needFindHead;
         }
 
@@ -24,7 +22,6 @@ namespace SourceGit.Commands
             var nextPartIdx = 0;
             var start = 0;
             var end = rs.StdOut.IndexOf('\n', start);
-            var max = rs.StdOut.Length;
             while (end > 0)
             {
                 var line = rs.StdOut.Substring(start, end - start);
@@ -51,24 +48,17 @@ namespace SourceGit.Commands
                         break;
                     case 6:
                         _current.CommitterTime = ulong.Parse(line);
-                        start = end + 1;
+                        break;
-                        end = rs.StdOut.IndexOf(_endOfBodyToken, start, StringComparison.Ordinal);
+                    case 7:
-                        if (end > 0)
+                        _current.Subject = line;
-                        {
+                        break;
-                            if (end > start)
-                                _current.Body = rs.StdOut.Substring(start, end - start).TrimEnd();
-
-                            start = end + _endOfBodyToken.Length + 1;
-                            end = start >= max ? -1 : rs.StdOut.IndexOf('\n', start);
-                        }
-
-                        nextPartIdx = 0;
-                        continue;
                     default:
                         break;
                 }
 
                 nextPartIdx++;
+                if (nextPartIdx == 8) nextPartIdx = 0;
+                
                 start = end + 1;
                 end = rs.StdOut.IndexOf('\n', start);
             }
@@ -157,7 +147,7 @@ namespace SourceGit.Commands
                 if (l.Type != r.Type)
                     return (int)l.Type - (int)r.Type;
                 else
-                    return l.Name.CompareTo(r.Name);
+                    return string.Compare(l.Name, r.Name, StringComparison.Ordinal);
             });
 
             if (_current.IsMerged && !_isHeadFounded)
@@ -187,7 +177,6 @@ namespace SourceGit.Commands
             }
         }
 
-        private string _endOfBodyToken = string.Empty;
         private List<Models.Commit> _commits = new List<Models.Commit>();
         private Models.Commit _current = null;
         private bool _findFirstMerged = false;

src/Commands/QuerySingleCommit.cs

@@ -10,7 +10,7 @@ namespace SourceGit.Commands
         {
             WorkingDirectory = repo;
             Context = repo;
-            Args = $"show --no-show-signature --decorate=full --pretty=format:%H%n%P%n%D%n%aN±%aE%n%at%n%cN±%cE%n%ct%n%B -s {sha}";
+            Args = $"show --no-show-signature --decorate=full --pretty=format:%H%n%P%n%D%n%aN±%aE%n%at%n%cN±%cE%n%ct%n%s -s {sha}";
         }
 
         public Models.Commit Result()
@@ -32,11 +32,7 @@ namespace SourceGit.Commands
                 commit.AuthorTime = ulong.Parse(lines[4]);
                 commit.Committer = Models.User.FindOrAdd(lines[5]);
                 commit.CommitterTime = ulong.Parse(lines[6]);
-
+                commit.Subject = lines[7];
-                StringBuilder builder = new StringBuilder();
-                for (int i = 7; i < lines.Length; i++)
-                    builder.AppendLine(lines[i]);
-                commit.Body = builder.ToString().TrimEnd();
 
                 return commit;
             }
@@ -105,7 +101,7 @@ namespace SourceGit.Commands
                 if (l.Type != r.Type)
                     return (int)l.Type - (int)r.Type;
                 else
-                    return l.Name.CompareTo(r.Name);
+                    return string.Compare(l.Name, r.Name, StringComparison.Ordinal);
             });
 
             return isHeadOfCurrent;

src/Models/Commit.cs

@@ -12,31 +12,13 @@ namespace SourceGit.Models
         public ulong AuthorTime { get; set; } = 0;
         public User Committer { get; set; } = User.Invalid;
         public ulong CommitterTime { get; set; } = 0;
-        public string Body { get; set; } = string.Empty;
+        public string Subject { get; set; } = string.Empty;
         public List<string> Parents { get; set; } = new List<string>();
         public List<Decorator> Decorators { get; set; } = new List<Decorator>();
         public bool HasDecorators => Decorators.Count > 0;
         public bool IsMerged { get; set; } = false;
         public Thickness Margin { get; set; } = new Thickness(0);
 
-        public string Subject
-        {
-            get
-            {
-                var end = Body.IndexOf("\r\n\r\n", StringComparison.Ordinal);
-                if (end == -1)
-                {
-                    end = Body.IndexOf("\n\n", StringComparison.Ordinal);
-                    if (end > 0)
-                        return Body.Substring(0, end).Replace("\n", "", StringComparison.Ordinal);
-
-                    return Body.Replace("\n", " ", StringComparison.Ordinal);
-                }
-
-                return Body.Substring(0, end).Replace("\r\n", " ", StringComparison.Ordinal);
-            }
-        }
-
         public string AuthorTimeStr => _utcStart.AddSeconds(AuthorTime).ToString("yyyy/MM/dd HH:mm:ss");
         public string CommitterTimeStr => _utcStart.AddSeconds(CommitterTime).ToString("yyyy/MM/dd HH:mm:ss");
         public string AuthorTimeShortStr => _utcStart.AddSeconds(AuthorTime).ToString("yyyy/MM/dd");

src/ViewModels/CommitDetail.cs

@@ -36,6 +36,12 @@ namespace SourceGit.ViewModels
             }
         }
 
+        public string FullMessage
+        {
+            get => _fullMessage;
+            private set => SetProperty(ref _fullMessage, value);
+        }
+
         public List<Models.Change> Changes
         {
             get => _changes;
@@ -376,6 +382,7 @@ namespace SourceGit.ViewModels
         private void Refresh()
         {
             _changes = null;
+            FullMessage = string.Empty;
             VisibleChanges = null;
             SelectedChanges = null;
 
@@ -389,6 +396,7 @@ namespace SourceGit.ViewModels
 
             Task.Run(() =>
             {
+                var fullMessage = new Commands.QueryCommitFullMessage(_repo, _commit.SHA).Result();
                 var parent = _commit.Parents.Count == 0 ? "4b825dc642cb6eb9a060e54bf8d69288fbee4904" : _commit.Parents[0];
                 var cmdChanges = new Commands.CompareRevisions(_repo, parent, _commit.SHA) { Cancel = _cancelToken };
                 var changes = cmdChanges.Result();
@@ -407,6 +415,7 @@ namespace SourceGit.ViewModels
                 {
                     Dispatcher.UIThread.Post(() =>
                     {
+                        FullMessage = fullMessage;
                         Changes = changes;
                         VisibleChanges = visible;
                     });
@@ -444,6 +453,7 @@ namespace SourceGit.ViewModels
         private string _repo = string.Empty;
         private int _activePageIndex = 0;
         private Models.Commit _commit = null;
+        private string _fullMessage = string.Empty;
         private List<Models.Change> _changes = null;
         private List<Models.Change> _visibleChanges = null;
         private List<Models.Change> _selectedChanges = null;

src/ViewModels/Repository.cs

@@ -429,7 +429,7 @@ namespace SourceGit.ViewModels
                 foreach (var c in _histories.Commits)
                 {
                     if (c.SHA.Contains(_searchCommitFilter, StringComparison.OrdinalIgnoreCase)
-                        || c.Body.Contains(_searchCommitFilter, StringComparison.OrdinalIgnoreCase)
+                        || c.Subject.Contains(_searchCommitFilter, StringComparison.OrdinalIgnoreCase)
                         || c.Author.Name.Contains(_searchCommitFilter, StringComparison.OrdinalIgnoreCase)
                         || c.Committer.Name.Contains(_searchCommitFilter, StringComparison.OrdinalIgnoreCase)
                         || c.Author.Email.Contains(_searchCommitFilter, StringComparison.OrdinalIgnoreCase)

src/ViewModels/Reword.cs

@@ -1,4 +1,5 @@
-using System.ComponentModel.DataAnnotations;
+using System;
+using System.ComponentModel.DataAnnotations;
 using System.Threading.Tasks;
 
 namespace SourceGit.ViewModels
@@ -21,14 +22,16 @@ namespace SourceGit.ViewModels
         public Reword(Repository repo, Models.Commit head)
         {
             _repo = repo;
+            _oldMessage = new Commands.QueryCommitFullMessage(_repo.FullPath, head.SHA).Result();
+            _message = _oldMessage;
+            
             Head = head;
-            Message = head.Body;
             View = new Views.Reword() { DataContext = this };
         }
 
         public override Task<bool> Sure()
         {
-            if (_message == Head.Body)
+            if (string.Compare(_message, _oldMessage, StringComparison.Ordinal) == 0)
                 return null;
 
             _repo.SetWatcherEnabled(false);
@@ -44,5 +47,6 @@ namespace SourceGit.ViewModels
 
         private readonly Repository _repo = null;
         private string _message = string.Empty;
+        private string _oldMessage = string.Empty;
     }
 }

src/ViewModels/Squash.cs

@@ -27,7 +27,8 @@ namespace SourceGit.ViewModels
         public Squash(Repository repo, Models.Commit head, Models.Commit parent)
         {
             _repo = repo;
-            _message = parent.Body;
+            _message = new Commands.QueryCommitFullMessage(_repo.FullPath, parent.SHA).Result();
+            
             Head = head;
             Parent = parent;
             View = new Views.Squash() { DataContext = this };

src/ViewModels/WorkingCopy.cs

@@ -93,16 +93,7 @@ namespace SourceGit.ViewModels
                         return;
                     }
 
-                    var head = new Commands.QuerySingleCommit(_repo.FullPath, currentBranch.Head).Result();
+                    CommitMessage = new Commands.QueryCommitFullMessage(_repo.FullPath, currentBranch.Head).Result();
-                    if (head == null)
-                    {
-                        App.RaiseException(_repo.FullPath, "No commits to amend!!!");
-                        _useAmend = false;
-                        OnPropertyChanged();
-                        return;
-                    }
-
-                    CommitMessage = head.Body;
                 }
 
                 OnPropertyChanged(nameof(IsCommitWithPushVisible));

src/Views/CommitBaseInfo.axaml

@@ -7,14 +7,15 @@
              xmlns:v="using:SourceGit.Views"
              xmlns:c="using:SourceGit.Converters"
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
-             x:Class="SourceGit.Views.CommitBaseInfo">
+             x:Class="SourceGit.Views.CommitBaseInfo"
+             x:Name="ThisControl">
   <UserControl.DataTemplates>
     <DataTemplate DataType="m:Commit">
       <StackPanel Orientation="Vertical">
         <!-- Author & Committer -->
         <UniformGrid Rows="1" Margin="0,8">
           <!-- Author -->
-          <Grid Grid.Column="0" ColumnDefinitions="96,*">
+          <Grid ColumnDefinitions="96,*">
             <v:Avatar Grid.Column="0" Width="64" Height="64" HorizontalAlignment="Right" User="{Binding Author}"/>
             <StackPanel Grid.Column="1" Margin="16,0,8,0" Orientation="Vertical">
               <TextBlock Classes="group_header_label" Margin="0" Text="{DynamicResource Text.CommitDetail.Info.Author}"/>
@@ -30,7 +31,7 @@
           </Grid>
 
           <!-- Committer -->
-          <Grid Grid.Column="1" ColumnDefinitions="96,*" IsVisible="{Binding IsCommitterVisible}">
+          <Grid ColumnDefinitions="96,*" IsVisible="{Binding IsCommitterVisible}">
             <v:Avatar Grid.Column="0" Width="64" Height="64" HorizontalAlignment="Right" User="{Binding Committer}"/>
             <StackPanel Grid.Column="1" Margin="16,0,8,0" Orientation="Vertical">
               <TextBlock Classes="group_header_label" Margin="0" Text="{DynamicResource Text.CommitDetail.Info.Committer}"/>
@@ -104,7 +105,7 @@
           <!-- Messages -->
           <TextBlock Grid.Row="3" Grid.Column="0" Classes="info_label" Text="{DynamicResource Text.CommitDetail.Info.Message}" VerticalAlignment="Top" Margin="0,4,0,0" />
           <ScrollViewer Grid.Row="3" Grid.Column="1" Margin="12,5,8,0" MaxHeight="64" HorizontalScrollBarVisibility="Disabled" VerticalScrollBarVisibility="Auto">
-            <SelectableTextBlock Text="{Binding Body}" FontFamily="{Binding Source={x:Static vm:Preference.Instance}, Path=MonospaceFont}" TextWrapping="Wrap"/>
+            <SelectableTextBlock Text="{Binding #ThisControl.Message}" FontFamily="{Binding Source={x:Static vm:Preference.Instance}, Path=MonospaceFont}" TextWrapping="Wrap"/>
           </ScrollViewer>
         </Grid>
       </StackPanel>

src/Views/CommitBaseInfo.axaml.cs

@@ -14,6 +14,15 @@ namespace SourceGit.Views
             get => GetValue(CanNavigateProperty);
             set => SetValue(CanNavigateProperty, value);
         }
+        
+        public static readonly StyledProperty<string> MessageProperty =
+            AvaloniaProperty.Register<CommitBaseInfo, string>(nameof(Message), string.Empty);
+
+        public string Message
+        {
+            get => GetValue(MessageProperty);
+            set => SetValue(MessageProperty, value);
+        }
 
         public CommitBaseInfo()
         {

src/Views/CommitDetail.axaml

@@ -19,7 +19,7 @@
 
       <Grid RowDefinitions="Auto,1,*">
         <!-- Base Information -->
-        <v:CommitBaseInfo Grid.Row="0" Content="{Binding Commit}"/>
+        <v:CommitBaseInfo Grid.Row="0" Content="{Binding Commit}" Message="{Binding FullMessage}"/>
 
         <!-- Line -->
         <Rectangle Grid.Row="1" Height=".65" Margin="8" Fill="{DynamicResource Brush.Border2}" VerticalAlignment="Center"/>