Add test demonstrating problem with revert (or cherry-pick) during a rebase

This problem can't happen inside of lazygit itself right now, but this will
change in the future. It will only happen when you stopped in an interactive
rebase on an "edit" entry, and then you perform a revert or cherry-pick
consisting of more than one commit; in this situation lazygit will show a
conflict although there is none.

This is not possible with lazygit yet, as we don't support range-select for
reverting, and we don't use `git cherry-pick` for cherry-picking. Both will
change in the future, so it's good to fix this bug.

pkg/integration/tests/interactive_rebase/revert_during_rebase_when_stopped_on_edit.go

@@ -0,0 +1,67 @@
+package interactive_rebase
+
+import (
+	"github.com/jesseduffield/lazygit/pkg/config"
+	. "github.com/jesseduffield/lazygit/pkg/integration/components"
+)
+
+var RevertDuringRebaseWhenStoppedOnEdit = NewIntegrationTest(NewIntegrationTestArgs{
+	Description:  "Revert a series of commits while stopped in a rebase",
+	ExtraCmdArgs: []string{},
+	Skip:         false,
+	SetupConfig: func(cfg *config.AppConfig) {
+		// TODO: use our revert UI once we support range-select for reverts
+		cfg.GetUserConfig().CustomCommands = []config.CustomCommand{
+			{
+				Key:     "X",
+				Context: "commits",
+				Command: "git -c core.editor=: revert HEAD^ HEAD^^",
+			},
+		}
+	},
+	SetupRepo: func(shell *Shell) {
+		shell.EmptyCommit("master commit")
+		shell.NewBranch("branch")
+		shell.CreateNCommits(4)
+	},
+	Run: func(t *TestDriver, keys config.KeybindingConfig) {
+		t.Views().Commits().
+			Focus().
+			Lines(
+				Contains("commit 04").IsSelected(),
+				Contains("commit 03"),
+				Contains("commit 02"),
+				Contains("commit 01"),
+				Contains("master commit"),
+			).
+			NavigateToLine(Contains("commit 03")).
+			Press(keys.Universal.Edit).
+			Lines(
+				Contains("pick").Contains("commit 04"),
+				Contains("<-- YOU ARE HERE --- commit 03").IsSelected(),
+				Contains("commit 02"),
+				Contains("commit 01"),
+				Contains("master commit"),
+			).
+			Press("X").
+			Lines(
+				/* EXPECTED:
+				Contains("pick").Contains("commit 04"),
+				Contains(`<-- YOU ARE HERE --- Revert "commit 01"`).IsSelected(),
+				Contains(`Revert "commit 02"`),
+				Contains("commit 03"),
+				Contains("commit 02"),
+				Contains("commit 01"),
+				Contains("master commit"),
+				ACTUAL: */
+				Contains("pick").Contains("commit 04"),
+				Contains("edit").Contains("<-- CONFLICT --- commit 03").IsSelected(),
+				Contains(`Revert "commit 01"`),
+				Contains(`Revert "commit 02"`),
+				Contains("commit 03"),
+				Contains("commit 02"),
+				Contains("commit 01"),
+				Contains("master commit"),
+			)
+	},
+})

pkg/integration/tests/test_list.go

@@ -264,6 +264,7 @@ var tests = []*components.IntegrationTest{
 	interactive_rebase.QuickStartKeepSelectionRange,
 	interactive_rebase.Rebase,
 	interactive_rebase.RebaseWithCommitThatBecomesEmpty,
+	interactive_rebase.RevertDuringRebaseWhenStoppedOnEdit,
 	interactive_rebase.RevertMultipleCommitsInInteractiveRebase,
 	interactive_rebase.RevertSingleCommitInInteractiveRebase,
 	interactive_rebase.RewordCommitWithEditorAndFail,