Introduce '--keep-ansi' option to keep ANSI codes on output

This improves filtering mode by allowing cases when colors needed to be passed from input to output in filtering mode.

src/core.go

@@ -72,6 +72,7 @@ func Run(opts *Options, version string, revision string) {
 			}
 			item.text, item.colors = ansiProcessor(data)
 			item.text.Index = itemIndex
+			item.origText = &data
 			itemIndex++
 			return true
 		})

src/options.go

@@ -288,6 +288,7 @@ type Options struct {
 	Criteria     []criterion
 	Multi        int
 	Ansi         bool
+	KeepAnsi     bool
 	Mouse        bool
 	Theme        *tui.ColorTheme
 	Black        bool
@@ -1633,6 +1634,8 @@ func parseOptions(opts *Options, allArgs []string) {
 			opts.Multi = 0
 		case "--ansi":
 			opts.Ansi = true
+		case "--keep-ansi":
+			opts.KeepAnsi = true
 		case "--no-ansi":
 			opts.Ansi = false
 		case "--no-mouse":

src/terminal.go

@@ -202,6 +202,7 @@ type Terminal struct {
 	scrollbar          string
 	previewScrollbar   string
 	ansi               bool
+	keepAnsi           bool
 	tabstop            int
 	margin             [4]sizeSpec
 	padding            [4]sizeSpec
@@ -631,6 +632,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 		header0:            opts.Header,
 		ellipsis:           opts.Ellipsis,
 		ansi:               opts.Ansi,
+		keepAnsi:           opts.KeepAnsi,
 		tabstop:            opts.Tabstop,
 		hasLoadActions:     false,
 		triggerLoad:        false,
@@ -985,16 +987,17 @@ func (t *Terminal) output() bool {
 	if len(t.expect) > 0 {
 		t.printer(t.pressed)
 	}
+	stripAnsi := t.ansi && (!t.keepAnsi)
 	found := len(t.selected) > 0
 	if !found {
 		current := t.currentItem()
 		if current != nil {
-			t.printer(current.AsString(t.ansi))
+			t.printer(current.AsString(stripAnsi))
 			found = true
 		}
 	} else {
 		for _, sel := range t.sortSelected() {
-			t.printer(sel.item.AsString(t.ansi))
+			t.printer(sel.item.AsString(stripAnsi))
 		}
 	}
 	return found