Add bare-minimum support for multi-line stash-message

With these changes, a multi-line message cannow be copied-into, viewed and copied-out-of a Stash:
* Simplify parsing in QueryStashes, by passing the `-z` argument to `git stash list` for item separation.
* Query full Message (`%B`) from stash (list-item still shows only first (Subject) line, tooltip shows full Message).
* Add "Copy Message" command in stash-item context-menu.
* Make the "Message:" text-box in StashChanges dialog support multiple lines, without changing the layout.

src/Commands/QueryStashes.cs

@@ -9,7 +9,7 @@ namespace SourceGit.Commands
         {
             WorkingDirectory = repo;
             Context = repo;
-            Args = "stash list --format=%H%n%P%n%ct%n%gd%n%s";
+            Args = "stash list -z --format=%H%n%P%n%ct%n%gd%n%B";
         }
 
         public List<Models.Stash> Result()
@@ -19,55 +19,54 @@ namespace SourceGit.Commands
             if (!rs.IsSuccess)
                 return outs;
 
+            var stashes = rs.StdOut.Split('\0', System.StringSplitOptions.RemoveEmptyEntries);
+            foreach (var stash in stashes)
+            {
+                var current = new Models.Stash();
+
                 var nextPartIdx = 0;
                 var start = 0;
-            var end = rs.StdOut.IndexOf('\n', start);
+                var end = stash.IndexOf('\n', start);
-            while (end > 0)
+                while (end > 0 && nextPartIdx < 4)
                 {
-                var line = rs.StdOut.Substring(start, end - start);
+                    var line = stash.Substring(start, end - start);
 
                     switch (nextPartIdx)
                     {
                         case 0:
-                        _current = new Models.Stash() { SHA = line };
+                            current = new Models.Stash() { SHA = line };
-                        outs.Add(_current);
                             break;
                         case 1:
-                        ParseParent(line);
+                            ParseParent(line, ref current);
                             break;
                         case 2:
-                        _current.Time = ulong.Parse(line);
+                            current.Time = ulong.Parse(line);
                             break;
                         case 3:
-                        _current.Name = line;
+                            current.Name = line;
-                        break;
-                    case 4:
-                        _current.Message = line;
                             break;
                     }
 
                     nextPartIdx++;
-                if (nextPartIdx > 4)
-                    nextPartIdx = 0;
 
                     start = end + 1;
-                end = rs.StdOut.IndexOf('\n', start);
+                    end = stash.IndexOf('\n', start);
                 }
 
-            if (start < rs.StdOut.Length)
+                if (start < stash.Length)
-                _current.Message = rs.StdOut.Substring(start);
+                    current.Message = stash.Substring(start);
 
+                outs.Add(current);
+            }
             return outs;
         }
 
-        private void ParseParent(string data)
+        private void ParseParent(string data, ref Models.Stash current)
         {
             if (data.Length < 8)
                 return;
 
-            _current.Parents.AddRange(data.Split(separator: ' ', options: StringSplitOptions.RemoveEmptyEntries));
+            current.Parents.AddRange(data.Split(separator: ' ', options: StringSplitOptions.RemoveEmptyEntries));
         }
-
-        private Models.Stash _current = null;
     }
 }

src/Resources/Locales/en_US.axaml

@@ -697,6 +697,7 @@
   <x:String x:Key="Text.Stash.TipForSelectedFiles" xml:space="preserve">Both staged and unstaged changes of selected file(s) will be stashed!!!</x:String>
   <x:String x:Key="Text.Stash.Title" xml:space="preserve">Stash Local Changes</x:String>
   <x:String x:Key="Text.StashCM.Apply" xml:space="preserve">Apply</x:String>
+  <x:String x:Key="Text.StashCM.CopyMessage" xml:space="preserve">Copy Message</x:String>
   <x:String x:Key="Text.StashCM.Drop" xml:space="preserve">Drop</x:String>
   <x:String x:Key="Text.StashCM.SaveAsPatch" xml:space="preserve">Save as Patch...</x:String>
   <x:String x:Key="Text.StashDropConfirm" xml:space="preserve">Drop Stash</x:String>

src/ViewModels/StashesPage.cs

@@ -194,11 +194,21 @@ namespace SourceGit.ViewModels
                 e.Handled = true;
             };
 
+            var copy = new MenuItem();
+            copy.Header = App.Text("StashCM.CopyMessage");
+            copy.Icon = App.CreateMenuIcon("Icons.Copy");
+            copy.Click += (_, ev) =>
+            {
+                App.CopyText(stash.Message);
+                ev.Handled = true;
+            };
+
             var menu = new ContextMenu();
             menu.Items.Add(apply);
             menu.Items.Add(drop);
             menu.Items.Add(new MenuItem { Header = "-" });
             menu.Items.Add(patch);
+            menu.Items.Add(copy);
             return menu;
         }
 

src/Views/StashChanges.axaml

@@ -20,6 +20,7 @@
       <TextBox Grid.Row="0" Grid.Column="1"
                Height="26"
                CornerRadius="3"
+               AcceptsReturn="True"
                Text="{Binding Message, Mode=TwoWay}"
                Watermark="{DynamicResource Text.Stash.Message.Placeholder}"
                v:AutoFocusBehaviour.IsEnabled="True"/>