feature(LFS): LFS diff and preview support

src/Git/Diff.cs

@@ -31,14 +31,6 @@ namespace SourceGit.Git {
             Both,
         }
 
-        /// <summary>
-        ///     Binary change.
-        /// </summary>
-        public class BinaryChange {
-            public long Size = 0;
-            public long PreSize = 0;
-        }
-
         /// <summary>
         ///     Block
         /// </summary>
@@ -63,9 +55,9 @@ namespace SourceGit.Git {
         }
 
         /// <summary>
-        ///     Diff result.
+        ///     Text file change.
         /// </summary>
-        public class Result {
+        public class TextChange {
             public bool IsValid = false;
             public bool IsBinary = false;
             public List<Block> Blocks = new List<Block>();
@@ -119,14 +111,31 @@ namespace SourceGit.Git {
             }
         }
 
+        /// <summary>
+        ///     Binary change.
+        /// </summary>
+        public class BinaryChange {
+            public long Size = 0;
+            public long PreSize = 0;
+        }
+
+        /// <summary>
+        ///     Change for LFS object information.
+        /// </summary>
+        public class LFSChange {
+            public LFSObject Old;
+            public LFSObject New;
+            public bool IsValid => Old != null || New != null;
+        }
+
         /// <summary>
         ///     Run diff process.
         /// </summary>
         /// <param name="repo"></param>
         /// <param name="args"></param>
         /// <returns></returns>
-        public static Result Run(Repository repo, string args) {
+        public static TextChange GetTextChange(Repository repo, string args) {
-            var rs = new Result();
+            var rs = new TextChange();
             var current = new Block();
             var left = 0;
             var right = 0;
@@ -259,5 +268,37 @@ namespace SourceGit.Git {
 
             return change;
         }
+
+        /// <summary>
+        ///     Get LFS object changes.
+        /// </summary>
+        /// <param name="repo"></param>
+        /// <param name="args"></param>
+        /// <returns></returns>
+        public static LFSChange GetLFSChange(Repository repo, string args) {
+            var rc = new LFSChange();
+
+            repo.RunCommand($"diff --ignore-cr-at-eol {args}", line => {
+                if (line[0] == '-') {
+                    if (rc.Old == null) rc.Old = new LFSObject();
+                    line = line.Substring(1);
+                    if (line.StartsWith("oid sha256:")) {
+                        rc.Old.OID = line.Substring(11);
+                    } else if (line.StartsWith("size ")) {
+                        rc.Old.Size = int.Parse(line.Substring(5));
+                    }
+                } else if (line[0] == '+') {
+                    if (rc.New == null) rc.New = new LFSObject();
+                    line = line.Substring(1);
+                    if (line.StartsWith("oid sha256:")) {
+                        rc.New.OID = line.Substring(11);
+                    } else if (line.StartsWith("size ")) {
+                        rc.New.Size = int.Parse(line.Substring(5));
+                    }
+                }
+            });
+
+            return rc;
+        }
     }
 }

src/Git/LFS.cs

@@ -0,0 +1,18 @@
+namespace SourceGit.Git {
+    
+    /// <summary>
+    ///    Object filtered by LFS 
+    /// </summary>
+    public class LFSObject {
+
+        /// <summary>
+        ///     Object id
+        /// </summary>
+        public string OID { get; set; }
+
+        /// <summary>
+        ///     Object size.
+        /// </summary>
+        public long Size { get; set; }
+    }
+}

src/Git/Repository.cs

@@ -999,11 +999,46 @@ namespace SourceGit.Git {
         /// <returns></returns>
         public long GetFileSize(string sha, string path) {
             long size = 0;
+
             RunCommand($"cat-file -s {sha}:\"{path}\"", line => {
                 if (!long.TryParse(line, out size)) size = 0;
             });
+
             return size;
         }
+        
+        /// <summary>
+        ///     Detect if a file is managed by LFS.
+        /// </summary>
+        /// <param name="path">File path</param>
+        /// <returns></returns>
+        public bool IsLFSFiltered(string path) {
+            bool ok = false;
+            RunCommand($"check-attr -a -z \"{path}\"", line => {
+                ok = ok || line.Contains("filter\0lfs");
+            });
+            return ok;
+        }
+
+        /// <summary>
+        ///     Get LFS object information.
+        /// </summary>
+        /// <param name="sha"></param>
+        /// <param name="path"></param>
+        /// <returns></returns>
+        public LFSObject GetLFSObject(string sha, string path) {
+            LFSObject obj = new LFSObject();
+
+            RunCommand($"show {sha}:\"{path}\"", line => {
+                if (line.StartsWith("oid")) {
+                    obj.OID = line.Substring(3).Replace("sha256:", "").Trim();
+                } else if (line.StartsWith("size")) {
+                    obj.Size = int.Parse(line.Substring(4).Trim());
+                }                
+            });
+
+            return obj;
+        }
         #endregion
 
         #region METHOD_GITFLOW

src/Resources/Icons.xaml

@@ -2,6 +2,7 @@
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
     <Geometry x:Key="Icon.Git">M1004.824 466.4L557.72 19.328c-25.728-25.76-67.488-25.76-93.28 0L360.568 123.2l78.176 78.176c12.544-5.984 26.56-9.376 41.376-9.376 53.024 0 96 42.976 96 96 0 14.816-3.36 28.864-9.376 41.376l127.968 127.968c12.544-5.984 26.56-9.376 41.376-9.376 53.024 0 96 42.976 96 96s-42.976 96-96 96-96-42.976-96-96c0-14.816 3.36-28.864 9.376-41.376L521.496 374.624a88.837 88.837 0 0 1-9.376 3.872v266.976c37.28 13.184 64 48.704 64 90.528 0 53.024-42.976 96-96 96s-96-42.976-96-96c0-41.792 26.72-77.344 64-90.528V378.496c-37.28-13.184-64-48.704-64-90.528 0-14.816 3.36-28.864 9.376-41.376l-78.176-78.176L19.416 464.288c-25.76 25.792-25.76 67.52 0 93.28l447.136 447.072c25.728 25.76 67.488 25.76 93.28 0l444.992-444.992c25.76-25.76 25.76-67.552 0-93.28z</Geometry>
     <Geometry x:Key="Icon.Submodule">M557.696 545.347L789.873 402.66c23.998-14.999 31.297-46.496 16.398-70.493-14.798-23.798-45.995-31.197-69.993-16.699L506.501 456.555 277.123 315.37c-24.098-14.798-55.595-7.3-70.493 16.799-14.799 24.097-7.3 55.594 16.798 70.493l231.778 142.586V819.12c0 28.297 22.897 51.195 51.195 51.195 28.297 0 51.195-22.898 51.195-51.195V545.347h0.1zM506.5 0l443.356 255.975v511.95L506.501 1023.9 63.144 767.925v-511.95L506.5 0z</Geometry>
+    <Geometry x:Key="Icon.LFS">M169.984 470.016l0 84.010667 86.016 0 0-84.010667-86.016 0zM86.016 598.016l0-171.989333 852.010667 0 0 171.989333-852.010667 0zM256 297.984l0-84.010667-86.016 0 0 84.010667 86.016 0zM86.016 169.984l852.010667 0 0 171.989333-852.010667 0 0-171.989333zM169.984 726.016l0 84.010667 86.016 0 0-84.010667-86.016 0zM86.016 854.016l0-171.989333 852.010667 0 0 171.989333-852.010667 0z</Geometry>
     
     <Geometry x:Key="Icon.ScrollLeft">M753.613 996.727L269.38 511.505 754.602 27.272z</Geometry>
     <Geometry x:Key="Icon.ScrollRight">M270.387 27.273L754.62 512.495 269.398 996.728z</Geometry>

src/UI/CommitViewer.xaml.cs

@@ -368,6 +368,12 @@ namespace SourceGit.UI {
 
             switch (node.CommitObject.Kind) {
             case Git.Commit.Object.Type.Blob:
+                if (repo.IsLFSFiltered(node.FilePath)) {
+                    var obj = repo.GetLFSObject(commit.SHA, node.FilePath);
+                    maskRevision.Visibility = Visibility.Visible;
+                    iconPreviewRevision.Data = FindResource("Icon.LFS") as Geometry;
+                    txtPreviewRevision.Content = $"LFS SIZE: {obj.Size} Bytes";
+                } else {
                     await Task.Run(() => {
                         var isBinary = false;
                         var data = commit.GetTextFileContent(repo, node.FilePath, out isBinary);
@@ -378,6 +384,7 @@ namespace SourceGit.UI {
                             Dispatcher.Invoke(() => filePreview.Text = data);
                         }
                     });
+                }
                 break;
             case Git.Commit.Object.Type.Tag:
                 maskRevision.Visibility = Visibility.Visible;

src/UI/DiffViewer.xaml

@@ -164,7 +164,7 @@
 
             <Border x:Name="sizeChange" Grid.Row="1" ClipToBounds="True" Background="{StaticResource Brush.BG3}" Visibility="Collapsed">
                 <StackPanel Orientation="Vertical" VerticalAlignment="Center">
-                    <Label Content="BINARY DIFF" Margin="0,0,0,32" FontSize="18" FontWeight="UltraBold" Foreground="{StaticResource Brush.FG2}" HorizontalAlignment="Center"/>
+                    <Label x:Name="txtSizeChangeTitle" Content="BINARY DIFF" Margin="0,0,0,32" FontSize="18" FontWeight="UltraBold" Foreground="{StaticResource Brush.FG2}" HorizontalAlignment="Center"/>
                     <Path Width="64" Height="64" Style="{StaticResource Style.Icon}" Data="{StaticResource Icon.Binary}" Fill="{StaticResource Brush.FG2}"/>
                     <Grid Margin="0,16,0,0" HorizontalAlignment="Center" TextElement.FontSize="18" TextElement.FontWeight="UltraBold">
                         <Grid.RowDefinitions>

src/UI/DiffViewer.xaml.cs

@@ -64,11 +64,22 @@ namespace SourceGit.UI {
                 if (!string.IsNullOrEmpty(opts.OrgPath)) args += $"\"{opts.OrgPath}\" ";
                 args += $"\"{opts.Path}\"";
 
-                var rs = Git.Diff.Run(repo, args);
+                if (repo.IsLFSFiltered(opts.Path)) {
+                    var lc = Git.Diff.GetLFSChange(repo, args);
+                    if (lc.IsValid) {
+                        SetLFSChange(lc);
+                    } else {
+                        SetSame();
+                    }
+
+                    return;
+                }
+
+                var rs = Git.Diff.GetTextChange(repo, args);
                 if (rs.IsBinary) {
-                    SetSizeChangeData(Git.Diff.GetSizeChange(repo, opts.RevisionRange, opts.Path, opts.OrgPath));
+                    SetBinaryChange(Git.Diff.GetSizeChange(repo, opts.RevisionRange, opts.Path, opts.OrgPath));
                 } else if (rs.Blocks.Count > 0) {
-                    SetData(rs);
+                    SetTextChange(rs);
                 } else {
                     SetSame();
                 }
@@ -91,36 +102,11 @@ namespace SourceGit.UI {
             }
         }
 
-        /// <summary>
-        ///     Show size changes.
-        /// </summary>
-        /// <param name="bc"></param>
-        private void SetSizeChangeData(Git.Diff.BinaryChange bc) {
-            Dispatcher.Invoke(() => {
-                loading.Visibility = Visibility.Collapsed;
-                sizeChange.Visibility = Visibility.Visible;
-                diffNavigation.Visibility = Visibility.Collapsed;
-                txtNewSize.Content = $"{bc.Size} Bytes";
-                txtOldSize.Content = $"{bc.PreSize} Bytes";
-            });
-        }
-
-        /// <summary>
-        ///     Show no changes or only EOL changes.
-        /// </summary>
-        private void SetSame() {
-            Dispatcher.Invoke(() => {
-                loading.Visibility = Visibility.Collapsed;
-                noChange.Visibility = Visibility.Visible;
-                diffNavigation.Visibility = Visibility.Collapsed;
-            });
-        }
-
         /// <summary>
         ///     Show diff content.
         /// </summary>
         /// <param name="rs"></param>
-        private void SetData(Git.Diff.Result rs) {
+        private void SetTextChange(Git.Diff.TextChange rs) {
             Dispatcher.Invoke(() => {
                 loading.Visibility = Visibility.Collapsed;
                 textChange.Visibility = Visibility.Visible;
@@ -141,6 +127,50 @@ namespace SourceGit.UI {
             });
         }
 
+        /// <summary>
+        ///     Show size changes.
+        /// </summary>
+        /// <param name="bc"></param>
+        private void SetBinaryChange(Git.Diff.BinaryChange bc) {
+            Dispatcher.Invoke(() => {
+                loading.Visibility = Visibility.Collapsed;
+                sizeChange.Visibility = Visibility.Visible;
+                diffNavigation.Visibility = Visibility.Collapsed;
+                txtSizeChangeTitle.Content = "BINARY DIFF";
+                txtNewSize.Content = $"{bc.Size} Bytes";
+                txtOldSize.Content = $"{bc.PreSize} Bytes";
+            });
+        }
+
+        /// <summary>
+        ///     Show size changes.
+        /// </summary>
+        /// <param name="lc"></param>
+        private void SetLFSChange(Git.Diff.LFSChange lc) {
+            Dispatcher.Invoke(() => {
+                var oldSize = lc.Old == null ? 0 : lc.Old.Size;
+                var newSize = lc.New == null ? 0 : lc.New.Size;
+
+                loading.Visibility = Visibility.Collapsed;
+                sizeChange.Visibility = Visibility.Visible;
+                diffNavigation.Visibility = Visibility.Collapsed;
+                txtSizeChangeTitle.Content = "LFS OBJECT CHANGE";
+                txtNewSize.Content = $"{newSize} Bytes";
+                txtOldSize.Content = $"{oldSize} Bytes";
+            });
+        }
+
+        /// <summary>
+        ///     Show no changes or only EOL changes.
+        /// </summary>
+        private void SetSame() {
+            Dispatcher.Invoke(() => {
+                loading.Visibility = Visibility.Collapsed;
+                noChange.Visibility = Visibility.Visible;
+                diffNavigation.Visibility = Visibility.Collapsed;
+            });
+        }
+
         /// <summary>
         ///     Make paragraph.
         /// </summary>