Add test for editing several commits right after a merge commit

This is very similar to edit_range_select_outside_rebase.go, except that it
selects commits right after, and including, a merge commit.

This test already works correctly. The reason we add it is that we are going to
have two different implementations of the `e` command depending on whether the
last selected commit is a merge commit, and we want to make sure they both work
with a range selection.

pkg/integration/tests/interactive_rebase/edit_range_select_down_to_merge_outside_rebase.go

@@ -0,0 +1,43 @@
+package interactive_rebase
+
+import (
+	"github.com/jesseduffield/lazygit/pkg/config"
+	. "github.com/jesseduffield/lazygit/pkg/integration/components"
+	"github.com/jesseduffield/lazygit/pkg/integration/tests/shared"
+)
+
+var EditRangeSelectDownToMergeOutsideRebase = NewIntegrationTest(NewIntegrationTestArgs{
+	Description:  "Select a range of commits (the last one being a merge commit) to edit outside of a rebase",
+	ExtraCmdArgs: []string{},
+	Skip:         false,
+	GitVersion:   AtLeast("2.22.0"), // first version that supports the --rebase-merges option
+	SetupConfig:  func(config *config.AppConfig) {},
+	SetupRepo: func(shell *Shell) {
+		shared.CreateMergeCommit(shell)
+		shell.CreateNCommits(2)
+	},
+	Run: func(t *TestDriver, keys config.KeybindingConfig) {
+		t.Views().Commits().
+			Focus().
+			TopLines(
+				Contains("CI ◯ commit 02").IsSelected(),
+				Contains("CI ◯ commit 01"),
+				Contains("Merge branch 'second-change-branch' into first-change-branch"),
+			).
+			Press(keys.Universal.RangeSelectDown).
+			Press(keys.Universal.RangeSelectDown).
+			Press(keys.Universal.Edit).
+			Lines(
+				Contains("edit  CI commit 02").IsSelected(),
+				Contains("edit  CI commit 01").IsSelected(),
+				Contains("      CI ⏣─╮ <-- YOU ARE HERE --- Merge branch 'second-change-branch' into first-change-branch").IsSelected(),
+				Contains("      CI │ ◯ * second-change-branch unrelated change"),
+				Contains("      CI │ ◯ second change"),
+				Contains("      CI ◯ │ first change"),
+				Contains("      CI ◯─╯ * original"),
+				Contains("      CI ◯ three"),
+				Contains("      CI ◯ two"),
+				Contains("      CI ◯ one"),
+			)
+	},
+})

pkg/integration/tests/test_list.go

@@ -214,6 +214,7 @@ var tests = []*components.IntegrationTest{
 	interactive_rebase.EditFirstCommit,
 	interactive_rebase.EditLastCommitOfStackedBranch,
 	interactive_rebase.EditNonTodoCommitDuringRebase,
+	interactive_rebase.EditRangeSelectDownToMergeOutsideRebase,
 	interactive_rebase.EditRangeSelectOutsideRebase,
 	interactive_rebase.EditTheConflCommit,
 	interactive_rebase.FixupFirstCommit,