Add 'load' event that is triggered when the input stream is complete

and the first search (with or without query) is complete

CHANGELOG.md

@@ -21,6 +21,16 @@ CHANGELOG
   # Put the cursor on the 10th to last item
   seq 100 | fzf --sync --bind 'start:pos(-10)'
   ```
+- Added `load` event that is triggered when the input stream is complete and
+  the initial processing of the list is complete.
+  ```sh
+  # Change the prompt to "loaded" when the input stream is complete
+  (seq 10; sleep 1; seq 11 20) | fzf --prompt 'Loading> ' --bind 'load:change-prompt:Loaded> '
+
+  # You can use it instead of 'start' event without `--sync` if asynchronous
+  # trigger is not an issue.
+  (seq 10; sleep 1; seq 11 20) | fzf --bind 'load:last'
+  ```
 - Added `next-selected` and `prev-selected` actions to move between selected
   items
   ```sh

man/man1/fzf.1

@@ -927,6 +927,15 @@ e.g.
      \fB# Move cursor to the last item and select all items
      seq 1000 | fzf --multi --sync --bind start:last+select-all\fR
 .RE
+\fIload\fR
+.RS
+Triggered when the input stream is complete and the initial processing of the
+list is complete.
+
+e.g.
+     \fB# Change the prompt to "loaded" when the input stream is complete
+     (seq 10; sleep 1; seq 11 20) | fzf --prompt 'Loading> ' --bind 'load:change-prompt:Loaded> '\fR
+.RE
 \fIchange\fR
 .RS
 Triggered whenever the query string is changed

src/options.go

@@ -590,6 +590,8 @@ func parseKeyChords(str string, message string) map[tui.Event]string {
 			add(tui.BackwardEOF)
 		case "start":
 			add(tui.Start)
+		case "load":
+			add(tui.Load)
 		case "alt-enter", "alt-return":
 			chords[tui.CtrlAltKey('m')] = key
 		case "alt-space":

src/terminal.go

@@ -177,6 +177,8 @@ type Terminal struct {
 	pwindow            tui.Window
 	count              int
 	progress           int
+	hasLoadActions     bool
+	triggerLoad        bool
 	reading            bool
 	running            bool
 	failed             *string
@@ -202,6 +204,7 @@ type Terminal struct {
 	startChan          chan fitpad
 	killChan           chan int
 	serverChan         chan []*action
+	eventChan          chan tui.Event
 	slab               *util.Slab
 	theme              *tui.ColorTheme
 	tui                tui.Renderer
@@ -579,6 +582,8 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 		ellipsis:           opts.Ellipsis,
 		ansi:               opts.Ansi,
 		tabstop:            opts.Tabstop,
+		hasLoadActions:     false,
+		triggerLoad:        false,
 		reading:            true,
 		running:            true,
 		failed:             nil,
@@ -603,6 +608,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 		startChan:          make(chan fitpad, 1),
 		killChan:           make(chan int),
 		serverChan:         make(chan []*action, 10),
+		eventChan:          make(chan tui.Event, 1),
 		tui:                renderer,
 		initFunc:           func() { renderer.Init() },
 		executing:          util.NewAtomicBool(false)}
@@ -624,6 +630,8 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 		t.separator, t.separatorLen = t.ansiLabelPrinter(bar, &tui.ColSeparator, true)
 	}
 
+	_, t.hasLoadActions = t.keymap[tui.Load.AsEvent()]
+
 	if err := startHttpServer(t.listenPort, t.serverChan); err != nil {
 		errorExit(err.Error())
 	}
@@ -763,6 +771,9 @@ func (t *Terminal) Input() (bool, []rune) {
 func (t *Terminal) UpdateCount(cnt int, final bool, failedCommand *string) {
 	t.mutex.Lock()
 	t.count = cnt
+	if t.hasLoadActions && t.reading && final {
+		t.triggerLoad = true
+	}
 	t.reading = !final
 	t.failed = failedCommand
 	t.mutex.Unlock()
@@ -811,6 +822,10 @@ func (t *Terminal) UpdateList(merger *Merger, reset bool) {
 		t.selected = make(map[int32]selectedItem)
 		t.version++
 	}
+	if t.hasLoadActions && t.triggerLoad {
+		t.triggerLoad = false
+		t.eventChan <- tui.Load.AsEvent()
+	}
 	t.mutex.Unlock()
 	t.reqBox.Set(reqInfo, nil)
 	t.reqBox.Set(reqList, nil)
@@ -2515,13 +2530,12 @@ func (t *Terminal) Loop() {
 	looping := true
 	_, startEvent := t.keymap[tui.Start.AsEvent()]
 
-	eventChan := make(chan tui.Event)
 	needBarrier := true
 	barrier := make(chan bool)
 	go func() {
 		for {
 			<-barrier
-			eventChan <- t.tui.GetChar()
+			t.eventChan <- t.tui.GetChar()
 		}
 	}()
 	for looping {
@@ -2540,8 +2554,8 @@ func (t *Terminal) Loop() {
 				barrier <- true
 			}
 			select {
-			case event = <-eventChan:
+			case event = <-t.eventChan:
-				needBarrier = true
+				needBarrier = event != tui.Load.AsEvent()
 			case actions = <-t.serverChan:
 				event = tui.Invalid.AsEvent()
 				needBarrier = false

src/tui/tui.go

@@ -91,6 +91,7 @@ const (
 	Change
 	BackwardEOF
 	Start
+	Load
 
 	AltBS