Add --keep-right option to keep the right end of the line visible

Close #1652

5 files changed, 31 insertions, 6 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 41d949e3..e9f26eec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,8 @@ CHANGELOG
 - Added `--pointer` and `--marker` options
 - `--height` option is now available on Windows binary (@kelleyma49)
 - More keys and actions for `--bind`
+- Added `--keep-right` option that keeps the right end of the line visible
+  when it's too long
 - Bug fixes and improvements
 - Vim plugin: Floating windows support
 - bash: Various improvements in key bindings (CTRL-T, CTRL-R, ALT-C)
diff --git a/man/man1/fzf.1 b/man/man1/fzf.1
index 5c39f367..cb8f51e7 100644
--- a/man/man1/fzf.1
+++ b/man/man1/fzf.1
@@ -130,6 +130,10 @@ the details.
 .B "--cycle"
 Enable cyclic scroll
 .TP
+.B "--keep-right"
+Keep the right end of the line visible when it's too long. Effective only when
+the query string is empty.
+.TP
 .B "--no-hscroll"
 Disable horizontal scroll
 .TP
diff --git a/src/options.go b/src/options.go
index 0fd97050..32c50af5 100644
--- a/src/options.go
+++ b/src/options.go
@@ -44,6 +44,7 @@ const usage = `usage: fzf [options]
     --no-mouse            Disable mouse
     --bind=KEYBINDS       Custom key bindings. Refer to the man page.
     --cycle               Enable cyclic scroll
+    --keep-right          Keep the right end of the line visible on overflow
     --no-hscroll          Disable horizontal scroll
     --hscroll-off=COL     Number of screen columns to keep to the right of the
                           highlighted substring (default: 10)
@@ -187,6 +188,7 @@ type Options struct {
 	MinHeight   int
 	Layout      layoutType
 	Cycle       bool
+	KeepRight   bool
 	Hscroll     bool
 	HscrollOff  int
 	FileWord    bool
@@ -242,6 +244,7 @@ func defaultOptions() *Options {
 		MinHeight:   10,
 		Layout:      layoutDefault,
 		Cycle:       false,
+		KeepRight:   false,
 		Hscroll:     true,
 		HscrollOff:  10,
 		FileWord:    false,
@@ -1174,6 +1177,10 @@ func parseOptions(opts *Options, allArgs []string) {
 			opts.Cycle = true
 		case "--no-cycle":
 			opts.Cycle = false
+		case "--keep-right":
+			opts.KeepRight = true
+		case "--no-keep-right":
+			opts.KeepRight = false
 		case "--hscroll":
 			opts.Hscroll = true
 		case "--no-hscroll":
diff --git a/src/terminal.go b/src/terminal.go
index a6a5c5ba..0cb45c90 100644
--- a/src/terminal.go
+++ b/src/terminal.go
@@ -25,6 +25,8 @@ import (
 var placeholder *regexp.Regexp
 var activeTempFiles []string
 
+const ellipsis string = ".."
+
 func init() {
 	placeholder = regexp.MustCompile(`\\?(?:{[+sf]*[0-9,-.]*}|{q}|{\+?f?nf?})`)
 	activeTempFiles = []string{}
@@ -73,6 +75,7 @@ type Terminal struct {
 	queryLen     [2]int
 	layout       layoutType
 	fullscreen   bool
+	keepRight    bool
 	hscroll      bool
 	hscrollOff   int
 	wordRubout   string
@@ -397,6 +400,7 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 		queryLen:    [2]int{0, 0},
 		layout:      opts.Layout,
 		fullscreen:  fullscreen,
+		keepRight:   opts.KeepRight,
 		hscroll:     opts.Hscroll,
 		hscrollOff:  opts.HscrollOff,
 		wordRubout:  wordRubout,
@@ -1000,14 +1004,17 @@ func (t *Terminal) printHighlighted(result Result, attr tui.Attr, col1 tui.Color
 	displayWidth := t.displayWidthWithLimit(text, 0, maxWidth)
 	if displayWidth > maxWidth {
 		if t.hscroll {
-			// Stri..
-			if !t.overflow(text[:maxe], maxWidth-2) {
+			if t.keepRight && pos == nil {
+				text, _ = t.trimLeft(text, maxWidth-2)
+				text = append([]rune(ellipsis), text...)
+			} else if !t.overflow(text[:maxe], maxWidth-2) {
+				// Stri..
 				text, _ = t.trimRight(text, maxWidth-2)
-				text = append(text, []rune("..")...)
+				text = append(text, []rune(ellipsis)...)
 			} else {
 				// Stri..
 				if t.overflow(text[maxe:], 2) {
-					text = append(text[:maxe], []rune("..")...)
+					text = append(text[:maxe], []rune(ellipsis)...)
 				}
 				// ..ri..
 				var diff int32
@@ -1022,11 +1029,11 @@ func (t *Terminal) printHighlighted(result Result, attr tui.Attr, col1 tui.Color
 					offsets[idx].offset[0] = b
 					offsets[idx].offset[1] = util.Max32(b, e)
 				}
-				text = append([]rune(".."), text...)
+				text = append([]rune(ellipsis), text...)
 			}
 		} else {
 			text, _ = t.trimRight(text, maxWidth-2)
-			text = append(text, []rune("..")...)
+			text = append(text, []rune(ellipsis)...)
 
 			for idx, offset := range offsets {
 				offsets[idx].offset[0] = util.Min32(offset.offset[0], int32(maxWidth-2))
diff --git a/test/test_go.rb b/test/test_go.rb
index c640e2fb..ca862a53 100755
--- a/test/test_go.rb
+++ b/test/test_go.rb
@@ -1728,6 +1728,11 @@ class TestGoFZF < TestBase
       tmux.send_keys :Enter
     end
   end
+
+  def test_keep_right
+    tmux.send_keys("seq 10000 | #{FZF} --read0 --keep-right", :Enter)
+    tmux.until { |lines| lines.any_include?('9999 10000') }
+  end
 end
 
 module TestShell