feature: auto add checkout target branch to history filters if the filter list is not empty (#518)

src/ViewModels/Checkout.cs

@@ -62,7 +62,16 @@ namespace SourceGit.ViewModels
                     rs = new Commands.Stash(_repo.FullPath).Pop("stash@{0}");
                 }
 
-                CallUIThread(() => _repo.SetWatcherEnabled(true));
+                CallUIThread(() =>
+                {
+                    var b = _repo.Branches.Find(x => x.IsLocal && x.Name == Branch);
+                    if (b != null)
+                        _repo.AutoAddBranchFilterPostCheckout(b);
+
+                    _repo.MarkBranchesDirtyManually();
+                    _repo.SetWatcherEnabled(true);
+                });
+
                 return rs;
             });
         }

src/ViewModels/CreateBranch.cs

@@ -126,6 +126,15 @@ namespace SourceGit.ViewModels
 
                 CallUIThread(() =>
                 {
+                    if (CheckoutAfterCreated)
+                    {
+                        _repo.AutoAddBranchFilterPostCheckout(new Models.Branch()
+                        {
+                            FullName = $"refs/heads/{_name}",
+                            Upstream = BasedOn is Models.Branch { IsLocal: false } remoteBranch ? remoteBranch.FullName : string.Empty,
+                        });
+                    }
+
                     _repo.MarkBranchesDirtyManually();
                     _repo.SetWatcherEnabled(true);
                 });

src/ViewModels/Repository.cs

@@ -659,6 +659,31 @@ namespace SourceGit.ViewModels
                 NavigateToCommit(_currentBranch.Head);
         }
 
+        public void AutoAddBranchFilterPostCheckout(Models.Branch local)
+        {
+            if (_settings.Filters.Count == 0 || _settings.Filters.Contains(local.FullName))
+                return;
+
+            var hasLeft = false;
+            foreach (var b in _branches)
+            {
+                if (!b.FullName.Equals(local.FullName, StringComparison.Ordinal) && 
+                    !b.FullName.Equals(local.Upstream, StringComparison.Ordinal) && 
+                    !_settings.Filters.Contains(b.FullName))
+                {
+                    hasLeft = true;
+                    break;
+                }
+            }
+
+            if (!hasLeft)
+                _settings.Filters.Clear();
+            else if (string.IsNullOrEmpty(local.Upstream) || _settings.Filters.Contains(local.Upstream))
+                _settings.Filters.Add(local.FullName);
+            else
+                _settings.Filters.AddRange([local.FullName, local.Upstream]);
+        }
+
         public void UpdateFilters(List<string> filters, bool toggle)
         {
             var changed = false;