Add a "Mark commit as base commit for rebase" command

This allows to do the equivalent of "git rebase --onto <target> <base>", by
first marking the <base> commit with the new command, and then selecting the
target branch and invoking the usual rebase command there.

2 files changed, 79 insertions, 0 deletions

diff --git a/pkg/integration/tests/branch/rebase_from_marked_base.go b/pkg/integration/tests/branch/rebase_from_marked_base.go
new file mode 100644
index 000000000..fb6ede722
--- /dev/null
+++ b/pkg/integration/tests/branch/rebase_from_marked_base.go
@@ -0,0 +1,78 @@
+package branch
+
+import (
+	"github.com/jesseduffield/lazygit/pkg/config"
+	. "github.com/jesseduffield/lazygit/pkg/integration/components"
+)
+
+var RebaseFromMarkedBase = NewIntegrationTest(NewIntegrationTestArgs{
+	Description:  "Rebase onto another branch from a marked base commit",
+	ExtraCmdArgs: []string{},
+	Skip:         false,
+	SetupConfig:  func(config *config.AppConfig) {},
+	SetupRepo: func(shell *Shell) {
+		shell.
+			NewBranch("base-branch").
+			EmptyCommit("one").
+			EmptyCommit("two").
+			EmptyCommit("three").
+			NewBranch("active-branch").
+			EmptyCommit("active one").
+			EmptyCommit("active two").
+			EmptyCommit("active three").
+			Checkout("base-branch").
+			NewBranch("target-branch").
+			EmptyCommit("target one").
+			EmptyCommit("target two").
+			Checkout("active-branch")
+	},
+	Run: func(t *TestDriver, keys config.KeybindingConfig) {
+		t.Views().Commits().
+			Focus().
+			Lines(
+				Contains("active three"),
+				Contains("active two"),
+				Contains("active one"),
+				Contains("three"),
+				Contains("two"),
+				Contains("one"),
+			).
+			NavigateToLine(Contains("active one")).
+			Press(keys.Commits.MarkCommitAsBaseForRebase).
+			Lines(
+				Contains("active three"),
+				Contains("active two"),
+				Contains("↑↑↑ Will rebase from here ↑↑↑ active one"),
+				Contains("three"),
+				Contains("two"),
+				Contains("one"),
+			)
+
+		t.Views().Information().Content(Contains("Marked a base commit for rebase"))
+
+		t.Views().Branches().
+			Focus().
+			Lines(
+				Contains("active-branch"),
+				Contains("target-branch"),
+				Contains("base-branch"),
+			).
+			SelectNextItem().
+			Press(keys.Branches.RebaseBranch)
+
+		t.ExpectPopup().Menu().
+			Title(Equals("Rebase 'active-branch' from marked base onto 'target-branch'")).
+			Select(Contains("Simple rebase")).
+			Confirm()
+
+		t.Views().Commits().Lines(
+			Contains("active three"),
+			Contains("active two"),
+			Contains("target two"),
+			Contains("target one"),
+			Contains("three"),
+			Contains("two"),
+			Contains("one"),
+		)
+	},
+})
diff --git a/pkg/integration/tests/test_list.go b/pkg/integration/tests/test_list.go
index 9dcb57dee..dfcd6c0ea 100644
--- a/pkg/integration/tests/test_list.go
+++ b/pkg/integration/tests/test_list.go
@@ -44,6 +44,7 @@ var tests = []*components.IntegrationTest{
 	branch.RebaseAndDrop,
 	branch.RebaseCancelOnConflict,
 	branch.RebaseDoesNotAutosquash,
+	branch.RebaseFromMarkedBase,
 	branch.Reset,
 	branch.ResetUpstream,
 	branch.SetUpstream,