rearranging todo items while interactively rebasing

3 files changed, 69 insertions, 7 deletions

diff --git a/pkg/commands/git.go b/pkg/commands/git.go
index d8530c209..b042e24da 100644
--- a/pkg/commands/git.go
+++ b/pkg/commands/git.go
@@ -598,7 +598,7 @@ func (c *GitCommand) MoveCommitDown(commits []*Commit, index int) error {
 	if len(commits) <= index+2 {
 		// assuming they aren't picking the bottom commit
 		// TODO: support more than say 30 commits and ensure this logic is correct, and i18n
-		return errors.New("Not enough room")
+		return errors.New(c.Tr.SLocalize("NoRoom"))
 	}
 
 	todo := ""
@@ -696,6 +696,7 @@ func (c *GitCommand) AmendTo(sha string) error {
 	return c.OSCommand.RunCommand(fmt.Sprintf("git %s rebase --interactive --autostash --autosquash %s^", c.OSCommand.Platform.skipEditorArg, sha))
 }
 
+// EditRebaseTodo sets the action at a given index in the git-rebase-todo file
 func (c *GitCommand) EditRebaseTodo(index int, action string) error {
 	fileName := ".git/rebase-merge/git-rebase-todo"
 	bytes, err := ioutil.ReadFile(fileName)
@@ -713,6 +714,24 @@ func (c *GitCommand) EditRebaseTodo(index int, action string) error {
 	return ioutil.WriteFile(fileName, []byte(result), 0644)
 }
 
+// MoveTodoDown moves a rebase todo item down by one position
+func (c *GitCommand) MoveTodoDown(index int) error {
+	fileName := ".git/rebase-merge/git-rebase-todo"
+	bytes, err := ioutil.ReadFile(fileName)
+	if err != nil {
+		return err
+	}
+
+	content := strings.Split(string(bytes), "\n")
+	contentIndex := len(content) - 2 - index
+
+	rearrangedContent := append(content[0:contentIndex-1], content[contentIndex], content[contentIndex-1])
+	rearrangedContent = append(rearrangedContent, content[contentIndex+1:]...)
+	result := strings.Join(rearrangedContent, "\n")
+
+	return ioutil.WriteFile(fileName, []byte(result), 0644)
+}
+
 // Revert reverts the selected commit by sha
 func (c *GitCommand) Revert(sha string) error {
 	return c.OSCommand.RunCommand(fmt.Sprintf("git revert %s", sha))
diff --git a/pkg/gui/commits_panel.go b/pkg/gui/commits_panel.go
index 77b0b54dd..8189079c2 100644
--- a/pkg/gui/commits_panel.go
+++ b/pkg/gui/commits_panel.go
@@ -222,6 +222,21 @@ func (gui *Gui) handleMidRebaseCommand(action string) (bool, error) {
 	return true, gui.refreshCommits(gui.g)
 }
 
+// handleMoveTodoDown like handleMidRebaseCommand but for moving an item up in the todo list
+func (gui *Gui) handleMoveTodoDown(index int) (bool, error) {
+	selectedCommit := gui.State.Commits[index]
+	if selectedCommit.Status != "rebasing" {
+		return false, nil
+	}
+	if gui.State.Commits[index+1].Status != "rebasing" {
+		return true, nil
+	}
+	if err := gui.GitCommand.MoveTodoDown(index); err != nil {
+		return true, gui.createErrorPanel(gui.g, err.Error())
+	}
+	return true, gui.refreshCommits(gui.g)
+}
+
 func (gui *Gui) handleCommitDelete(g *gocui.Gui, v *gocui.View) error {
 	applied, err := gui.handleMidRebaseCommand("drop")
 	if err != nil {
@@ -239,20 +254,45 @@ func (gui *Gui) handleCommitDelete(g *gocui.Gui, v *gocui.View) error {
 }
 
 func (gui *Gui) handleCommitMoveDown(g *gocui.Gui, v *gocui.View) error {
-	gui.State.Panels.Commits.SelectedLine++
+	index := gui.State.Panels.Commits.SelectedLine
+	selectedCommit := gui.State.Commits[index]
+	if selectedCommit.Status == "rebasing" {
+		if gui.State.Commits[index+1].Status != "rebasing" {
+			return nil
+		}
+		if err := gui.GitCommand.MoveTodoDown(index); err != nil {
+			return gui.createErrorPanel(gui.g, err.Error())
+		}
+		gui.State.Panels.Commits.SelectedLine++
+		return gui.refreshCommits(gui.g)
+	}
 
-	err := gui.GitCommand.MoveCommitDown(gui.State.Commits, gui.State.Panels.Commits.SelectedLine-1)
+	err := gui.GitCommand.MoveCommitDown(gui.State.Commits, index)
+	if err == nil {
+		gui.State.Panels.Commits.SelectedLine++
+	}
 	return gui.handleGenericMergeCommandResult(err)
 }
 
 func (gui *Gui) handleCommitMoveUp(g *gocui.Gui, v *gocui.View) error {
-	if gui.State.Panels.Commits.SelectedLine == 0 {
-		return gui.createErrorPanel(gui.g, "You cannot move the topmost commit up") // TODO: i18n
+	index := gui.State.Panels.Commits.SelectedLine
+	if index == 0 {
+		return nil
 	}
 
-	gui.State.Panels.Commits.SelectedLine--
+	selectedCommit := gui.State.Commits[index]
+	if selectedCommit.Status == "rebasing" {
+		if err := gui.GitCommand.MoveTodoDown(index - 1); err != nil {
+			return gui.createErrorPanel(gui.g, err.Error())
+		}
+		gui.State.Panels.Commits.SelectedLine--
+		return gui.refreshCommits(gui.g)
+	}
 
-	err := gui.GitCommand.MoveCommitDown(gui.State.Commits, gui.State.Panels.Commits.SelectedLine)
+	err := gui.GitCommand.MoveCommitDown(gui.State.Commits, index-1)
+	if err == nil {
+		gui.State.Panels.Commits.SelectedLine--
+	}
 	return gui.handleGenericMergeCommandResult(err)
 }
 
diff --git a/pkg/i18n/english.go b/pkg/i18n/english.go
index 88058b265..e910d855b 100644
--- a/pkg/i18n/english.go
+++ b/pkg/i18n/english.go
@@ -562,6 +562,9 @@ func addEnglish(i18nObject *i18n.Bundle) error {
 		}, &i18n.Message{
 			ID:    "ErrorOccurred",
 			Other: "An error occurred! Please create an issue at https://github.com/jesseduffield/lazygit/issues",
+		}, &i18n.Message{
+			ID:    "NoRoom",
+			Other: "Not enough room",
 		},
 	)
 }