supporing custom pagers step 1

8 files changed, 89 insertions, 8 deletions

diff --git a/pkg/gui/commit_files_panel.go b/pkg/gui/commit_files_panel.go
index 63458926b..5fa7a4683 100644
--- a/pkg/gui/commit_files_panel.go
+++ b/pkg/gui/commit_files_panel.go
@@ -50,7 +50,7 @@ func (gui *Gui) handleCommitFileSelect(g *gocui.Gui, v *gocui.View) error {
 	cmd := gui.OSCommand.ExecutableFromString(
 		gui.GitCommand.ShowCommitFileCmdStr(commitFile.Sha, commitFile.Name, false),
 	)
-	if err := gui.newCmdTask("main", cmd); err != nil {
+	if err := gui.newPtyTask("main", cmd); err != nil {
 		gui.Log.Error(err)
 	}
 
diff --git a/pkg/gui/commits_panel.go b/pkg/gui/commits_panel.go
index fe6b7acb9..0c901d085 100644
--- a/pkg/gui/commits_panel.go
+++ b/pkg/gui/commits_panel.go
@@ -67,7 +67,7 @@ func (gui *Gui) handleCommitSelect(g *gocui.Gui, v *gocui.View) error {
 	cmd := gui.OSCommand.ExecutableFromString(
 		gui.GitCommand.ShowCmdStr(commit.Sha),
 	)
-	if err := gui.newCmdTask("main", cmd); err != nil {
+	if err := gui.newPtyTask("main", cmd); err != nil {
 		gui.Log.Error(err)
 	}
 
diff --git a/pkg/gui/files_panel.go b/pkg/gui/files_panel.go
index 4e00dc523..6bd2c7076 100644
--- a/pkg/gui/files_panel.go
+++ b/pkg/gui/files_panel.go
@@ -62,7 +62,7 @@ func (gui *Gui) selectFile(alreadySelected bool) error {
 		gui.getSecondaryView().Title = gui.Tr.SLocalize("StagedChanges")
 		cmdStr := gui.GitCommand.DiffCmdStr(file, false, true)
 		cmd := gui.OSCommand.ExecutableFromString(cmdStr)
-		if err := gui.newCmdTask("secondary", cmd); err != nil {
+		if err := gui.newPtyTask("secondary", cmd); err != nil {
 			return err
 		}
 	} else {
@@ -76,7 +76,7 @@ func (gui *Gui) selectFile(alreadySelected bool) error {
 
 	cmdStr := gui.GitCommand.DiffCmdStr(file, false, !file.HasUnstagedChanges && file.HasStagedChanges)
 	cmd := gui.OSCommand.ExecutableFromString(cmdStr)
-	if err := gui.newCmdTask("main", cmd); err != nil {
+	if err := gui.newPtyTask("main", cmd); err != nil {
 		return err
 	}
 
diff --git a/pkg/gui/gui.go b/pkg/gui/gui.go
index 70c3c3f51..9289c4e31 100644
--- a/pkg/gui/gui.go
+++ b/pkg/gui/gui.go
@@ -211,6 +211,9 @@ type guiState struct {
 	Searching            searchingState
 	ScreenMode           int
 	SideView             *gocui.View
+	Ptmx                 *os.File
+	PrevMainWidth        int
+	PrevMainHeight       int
 }
 
 // for now the split view will always be on
@@ -247,6 +250,7 @@ func NewGui(log *logrus.Entry, gitCommand *commands.GitCommand, oSCommand *comma
 		},
 		ScreenMode: SCREEN_NORMAL,
 		SideView:   nil,
+		Ptmx:       nil,
 	}
 
 	gui := &Gui{
@@ -811,6 +815,15 @@ func (gui *Gui) layout(g *gocui.Gui) error {
 		}
 	}
 
+	mainViewWidth, mainViewHeight := gui.getMainView().Size()
+	if mainViewWidth != gui.State.PrevMainWidth || mainViewHeight != gui.State.PrevMainHeight {
+		gui.State.PrevMainWidth = mainViewWidth
+		gui.State.PrevMainHeight = mainViewHeight
+		if err := gui.onResize(); err != nil {
+			return err
+		}
+	}
+
 	// here is a good place log some stuff
 	// if you download humanlog and do tail -f development.log | humanlog
 	// this will let you see these branches as prettified json
@@ -942,7 +955,7 @@ func (gui *Gui) startBackgroundFetch() {
 
 // Run setup the gui with keybindings and start the mainloop
 func (gui *Gui) Run() error {
-	g, err := gocui.NewGui(gocui.OutputNormal, OverlappingEdges)
+	g, err := gocui.NewGui(gocui.Output256, OverlappingEdges)
 	if err != nil {
 		return err
 	}
diff --git a/pkg/gui/pty.go b/pkg/gui/pty.go
new file mode 100644
index 000000000..18fb98fda
--- /dev/null
+++ b/pkg/gui/pty.go
@@ -0,0 +1,21 @@
+package gui
+
+import (
+	"github.com/jesseduffield/pty"
+)
+
+func (gui *Gui) onResize() error {
+	if gui.State.Ptmx == nil {
+		return nil
+	}
+	mainView := gui.getMainView()
+	width, height := mainView.Size()
+
+	if err := pty.Setsize(gui.State.Ptmx, &pty.Winsize{Cols: uint16(width), Rows: uint16(height)}); err != nil {
+		return err
+	}
+
+	// TODO: handle resizing properly
+
+	return nil
+}
diff --git a/pkg/gui/reflog_panel.go b/pkg/gui/reflog_panel.go
index 37144d8c6..1837e2f7d 100644
--- a/pkg/gui/reflog_panel.go
+++ b/pkg/gui/reflog_panel.go
@@ -41,7 +41,7 @@ func (gui *Gui) handleReflogCommitSelect(g *gocui.Gui, v *gocui.View) error {
 	cmd := gui.OSCommand.ExecutableFromString(
 		gui.GitCommand.ShowCmdStr(commit.Sha),
 	)
-	if err := gui.newCmdTask("main", cmd); err != nil {
+	if err := gui.newPtyTask("main", cmd); err != nil {
 		gui.Log.Error(err)
 	}
 
diff --git a/pkg/gui/stash_panel.go b/pkg/gui/stash_panel.go
index db12767e8..92d84df9f 100644
--- a/pkg/gui/stash_panel.go
+++ b/pkg/gui/stash_panel.go
@@ -41,7 +41,7 @@ func (gui *Gui) handleStashEntrySelect(g *gocui.Gui, v *gocui.View) error {
 	cmd := gui.OSCommand.ExecutableFromString(
 		gui.GitCommand.ShowStashEntryCmdStr(stashEntry.Index),
 	)
-	if err := gui.newCmdTask("main", cmd); err != nil {
+	if err := gui.newPtyTask("main", cmd); err != nil {
 		gui.Log.Error(err)
 	}
 
diff --git a/pkg/gui/tasks_adapter.go b/pkg/gui/tasks_adapter.go
index 22ebb9da9..38d7ce36b 100644
--- a/pkg/gui/tasks_adapter.go
+++ b/pkg/gui/tasks_adapter.go
@@ -5,6 +5,7 @@ import (
 
 	"github.com/jesseduffield/gocui"
 	"github.com/jesseduffield/lazygit/pkg/tasks"
+	"github.com/jesseduffield/pty"
 )
 
 func (gui *Gui) newCmdTask(viewName string, cmd *exec.Cmd) error {
@@ -25,6 +26,49 @@ func (gui *Gui) newCmdTask(viewName string, cmd *exec.Cmd) error {
 	return nil
 }
 
+func (gui *Gui) newPtyTask(viewName string, cmd *exec.Cmd) error {
+	width, _ := gui.getMainView().Size()
+	pager, err := gui.GitCommand.GetPager(width)
+	if err != nil {
+		return err
+	}
+
+	if pager == "" {
+		// if we're not using a custom pager we don't need to use a pty
+		return gui.newCmdTask(viewName, cmd)
+	}
+
+	cmd.Env = append(cmd.Env, "GIT_PAGER="+pager)
+
+	view, err := gui.g.View(viewName)
+	if err != nil {
+		return nil // swallowing for now
+	}
+
+	_, height := view.Size()
+	_, oy := view.Origin()
+
+	manager := gui.getManager(view)
+
+	ptmx, err := pty.Start(cmd)
+	if err != nil {
+		return err
+	}
+
+	gui.State.Ptmx = ptmx
+	onClose := func() { gui.State.Ptmx = nil }
+
+	if err := gui.onResize(); err != nil {
+		return err
+	}
+
+	if err := manager.NewTask(manager.NewPtyTask(ptmx, cmd, height+oy+10, onClose)); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 func (gui *Gui) newTask(viewName string, f func(chan struct{}) error) error {
 	view, err := gui.g.View(viewName)
 	if err != nil {
@@ -69,7 +113,10 @@ func (gui *Gui) getManager(view *gocui.View) *tasks.ViewBufferManager {
 				view.Clear()
 			},
 			func() {
-				gui.g.Update(func(*gocui.Gui) error { return nil })
+				gui.g.Update(func(*gocui.Gui) error {
+					gui.Log.Warn("updating view")
+					return nil
+				})
 			})
 		gui.viewBufferManagerMap[view.Name()] = manager
 	}