Add change-ghost and transform-ghost

6 files changed, 153 insertions, 129 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 06dc3e77..0011c134 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ CHANGELOG
   # Display "Type to search" when the input is empty
   fzf --ghost "Type to search"
   ```
+- Added `change-ghost` and `transform-ghost` actions for dynamically changing the ghost text
 - Added `change-pointer` and `transform-pointer` actions for dynamically changing the pointer sign
 - Bug fixes and improvements
 
diff --git a/man/man1/fzf.1 b/man/man1/fzf.1
index 33ea2609..4b2c5896 100644
--- a/man/man1/fzf.1
+++ b/man/man1/fzf.1
@@ -1609,6 +1609,7 @@ A key or an event can be bound to one or more of the following actions.
     \fBbell\fR                         (ring the terminal bell)
     \fBcancel\fR                       (clear query string if not empty, abort fzf otherwise)
     \fBchange\-border\-label(...)\fR     (change \fB\-\-border\-label\fR to the given string)
+    \fBchange\-ghost(...)\fR            (change ghost text to the given string)
     \fBchange\-header(...)\fR           (change header to the given string; doesn't affect \fB\-\-header\-lines\fR)
     \fBchange\-header\-label(...)\fR     (change \fB\-\-header\-label\fR to the given string)
     \fBchange\-input\-label(...)\fR      (change \fB\-\-input\-label\fR to the given string)
@@ -1705,6 +1706,7 @@ A key or an event can be bound to one or more of the following actions.
     \fBtrack\-current\fR                (track the current item; automatically disabled if focus changes)
     \fBtransform(...)\fR               (transform states using the output of an external command)
     \fBtransform\-border\-label(...)\fR  (transform border label using an external command)
+    \fBtransform\-ghost(...)\fR         (transform ghost text using an external command)
     \fBtransform\-header(...)\fR        (transform header using an external command)
     \fBtransform\-header\-label(...)\fR  (transform header label using an external command)
     \fBtransform\-input\-label(...)\fR   (transform input label using an external command)
diff --git a/src/actiontype_string.go b/src/actiontype_string.go
index 19b5ea72..8b78008f 100644
--- a/src/actiontype_string.go
+++ b/src/actiontype_string.go
@@ -27,128 +27,130 @@ func _() {
 	_ = x[actBackwardWord-16]
 	_ = x[actCancel-17]
 	_ = x[actChangeBorderLabel-18]
-	_ = x[actChangeListLabel-19]
-	_ = x[actChangeInputLabel-20]
-	_ = x[actChangeHeader-21]
-	_ = x[actChangeHeaderLabel-22]
-	_ = x[actChangeMulti-23]
-	_ = x[actChangePreviewLabel-24]
-	_ = x[actChangePrompt-25]
-	_ = x[actChangeQuery-26]
-	_ = x[actChangeNth-27]
-	_ = x[actClearScreen-28]
-	_ = x[actClearQuery-29]
-	_ = x[actClearSelection-30]
-	_ = x[actClose-31]
-	_ = x[actDeleteChar-32]
-	_ = x[actDeleteCharEof-33]
-	_ = x[actEndOfLine-34]
-	_ = x[actFatal-35]
-	_ = x[actForwardChar-36]
-	_ = x[actForwardWord-37]
-	_ = x[actKillLine-38]
-	_ = x[actKillWord-39]
-	_ = x[actUnixLineDiscard-40]
-	_ = x[actUnixWordRubout-41]
-	_ = x[actYank-42]
-	_ = x[actBackwardKillWord-43]
-	_ = x[actSelectAll-44]
-	_ = x[actDeselectAll-45]
-	_ = x[actToggle-46]
-	_ = x[actToggleSearch-47]
-	_ = x[actToggleAll-48]
-	_ = x[actToggleDown-49]
-	_ = x[actToggleUp-50]
-	_ = x[actToggleIn-51]
-	_ = x[actToggleOut-52]
-	_ = x[actToggleTrack-53]
-	_ = x[actToggleTrackCurrent-54]
-	_ = x[actToggleHeader-55]
-	_ = x[actToggleWrap-56]
-	_ = x[actToggleMultiLine-57]
-	_ = x[actToggleHscroll-58]
-	_ = x[actTrackCurrent-59]
-	_ = x[actToggleInput-60]
-	_ = x[actHideInput-61]
-	_ = x[actShowInput-62]
-	_ = x[actUntrackCurrent-63]
-	_ = x[actDown-64]
-	_ = x[actUp-65]
-	_ = x[actPageUp-66]
-	_ = x[actPageDown-67]
-	_ = x[actPosition-68]
-	_ = x[actHalfPageUp-69]
-	_ = x[actHalfPageDown-70]
-	_ = x[actOffsetUp-71]
-	_ = x[actOffsetDown-72]
-	_ = x[actOffsetMiddle-73]
-	_ = x[actJump-74]
-	_ = x[actJumpAccept-75]
-	_ = x[actPrintQuery-76]
-	_ = x[actRefreshPreview-77]
-	_ = x[actReplaceQuery-78]
-	_ = x[actToggleSort-79]
-	_ = x[actShowPreview-80]
-	_ = x[actHidePreview-81]
-	_ = x[actTogglePreview-82]
-	_ = x[actTogglePreviewWrap-83]
-	_ = x[actTransform-84]
-	_ = x[actTransformBorderLabel-85]
-	_ = x[actTransformListLabel-86]
-	_ = x[actTransformInputLabel-87]
-	_ = x[actTransformHeader-88]
-	_ = x[actTransformHeaderLabel-89]
-	_ = x[actTransformNth-90]
-	_ = x[actTransformPointer-91]
-	_ = x[actTransformPreviewLabel-92]
-	_ = x[actTransformPrompt-93]
-	_ = x[actTransformQuery-94]
-	_ = x[actTransformSearch-95]
-	_ = x[actSearch-96]
-	_ = x[actPreview-97]
-	_ = x[actChangePointer-98]
-	_ = x[actChangePreview-99]
-	_ = x[actChangePreviewWindow-100]
-	_ = x[actPreviewTop-101]
-	_ = x[actPreviewBottom-102]
-	_ = x[actPreviewUp-103]
-	_ = x[actPreviewDown-104]
-	_ = x[actPreviewPageUp-105]
-	_ = x[actPreviewPageDown-106]
-	_ = x[actPreviewHalfPageUp-107]
-	_ = x[actPreviewHalfPageDown-108]
-	_ = x[actPrevHistory-109]
-	_ = x[actPrevSelected-110]
-	_ = x[actPrint-111]
-	_ = x[actPut-112]
-	_ = x[actNextHistory-113]
-	_ = x[actNextSelected-114]
-	_ = x[actExecute-115]
-	_ = x[actExecuteSilent-116]
-	_ = x[actExecuteMulti-117]
-	_ = x[actSigStop-118]
-	_ = x[actFirst-119]
-	_ = x[actLast-120]
-	_ = x[actReload-121]
-	_ = x[actReloadSync-122]
-	_ = x[actDisableSearch-123]
-	_ = x[actEnableSearch-124]
-	_ = x[actSelect-125]
-	_ = x[actDeselect-126]
-	_ = x[actUnbind-127]
-	_ = x[actRebind-128]
-	_ = x[actToggleBind-129]
-	_ = x[actBecome-130]
-	_ = x[actShowHeader-131]
-	_ = x[actHideHeader-132]
-	_ = x[actBell-133]
-	_ = x[actExclude-134]
-	_ = x[actExcludeMulti-135]
+	_ = x[actChangeGhost-19]
+	_ = x[actChangeHeader-20]
+	_ = x[actChangeHeaderLabel-21]
+	_ = x[actChangeInputLabel-22]
+	_ = x[actChangeListLabel-23]
+	_ = x[actChangeMulti-24]
+	_ = x[actChangeNth-25]
+	_ = x[actChangePointer-26]
+	_ = x[actChangePreview-27]
+	_ = x[actChangePreviewLabel-28]
+	_ = x[actChangePreviewWindow-29]
+	_ = x[actChangePrompt-30]
+	_ = x[actChangeQuery-31]
+	_ = x[actClearScreen-32]
+	_ = x[actClearQuery-33]
+	_ = x[actClearSelection-34]
+	_ = x[actClose-35]
+	_ = x[actDeleteChar-36]
+	_ = x[actDeleteCharEof-37]
+	_ = x[actEndOfLine-38]
+	_ = x[actFatal-39]
+	_ = x[actForwardChar-40]
+	_ = x[actForwardWord-41]
+	_ = x[actKillLine-42]
+	_ = x[actKillWord-43]
+	_ = x[actUnixLineDiscard-44]
+	_ = x[actUnixWordRubout-45]
+	_ = x[actYank-46]
+	_ = x[actBackwardKillWord-47]
+	_ = x[actSelectAll-48]
+	_ = x[actDeselectAll-49]
+	_ = x[actToggle-50]
+	_ = x[actToggleSearch-51]
+	_ = x[actToggleAll-52]
+	_ = x[actToggleDown-53]
+	_ = x[actToggleUp-54]
+	_ = x[actToggleIn-55]
+	_ = x[actToggleOut-56]
+	_ = x[actToggleTrack-57]
+	_ = x[actToggleTrackCurrent-58]
+	_ = x[actToggleHeader-59]
+	_ = x[actToggleWrap-60]
+	_ = x[actToggleMultiLine-61]
+	_ = x[actToggleHscroll-62]
+	_ = x[actTrackCurrent-63]
+	_ = x[actToggleInput-64]
+	_ = x[actHideInput-65]
+	_ = x[actShowInput-66]
+	_ = x[actUntrackCurrent-67]
+	_ = x[actDown-68]
+	_ = x[actUp-69]
+	_ = x[actPageUp-70]
+	_ = x[actPageDown-71]
+	_ = x[actPosition-72]
+	_ = x[actHalfPageUp-73]
+	_ = x[actHalfPageDown-74]
+	_ = x[actOffsetUp-75]
+	_ = x[actOffsetDown-76]
+	_ = x[actOffsetMiddle-77]
+	_ = x[actJump-78]
+	_ = x[actJumpAccept-79]
+	_ = x[actPrintQuery-80]
+	_ = x[actRefreshPreview-81]
+	_ = x[actReplaceQuery-82]
+	_ = x[actToggleSort-83]
+	_ = x[actShowPreview-84]
+	_ = x[actHidePreview-85]
+	_ = x[actTogglePreview-86]
+	_ = x[actTogglePreviewWrap-87]
+	_ = x[actTransform-88]
+	_ = x[actTransformBorderLabel-89]
+	_ = x[actTransformGhost-90]
+	_ = x[actTransformHeader-91]
+	_ = x[actTransformHeaderLabel-92]
+	_ = x[actTransformInputLabel-93]
+	_ = x[actTransformListLabel-94]
+	_ = x[actTransformNth-95]
+	_ = x[actTransformPointer-96]
+	_ = x[actTransformPreviewLabel-97]
+	_ = x[actTransformPrompt-98]
+	_ = x[actTransformQuery-99]
+	_ = x[actTransformSearch-100]
+	_ = x[actSearch-101]
+	_ = x[actPreview-102]
+	_ = x[actPreviewTop-103]
+	_ = x[actPreviewBottom-104]
+	_ = x[actPreviewUp-105]
+	_ = x[actPreviewDown-106]
+	_ = x[actPreviewPageUp-107]
+	_ = x[actPreviewPageDown-108]
+	_ = x[actPreviewHalfPageUp-109]
+	_ = x[actPreviewHalfPageDown-110]
+	_ = x[actPrevHistory-111]
+	_ = x[actPrevSelected-112]
+	_ = x[actPrint-113]
+	_ = x[actPut-114]
+	_ = x[actNextHistory-115]
+	_ = x[actNextSelected-116]
+	_ = x[actExecute-117]
+	_ = x[actExecuteSilent-118]
+	_ = x[actExecuteMulti-119]
+	_ = x[actSigStop-120]
+	_ = x[actFirst-121]
+	_ = x[actLast-122]
+	_ = x[actReload-123]
+	_ = x[actReloadSync-124]
+	_ = x[actDisableSearch-125]
+	_ = x[actEnableSearch-126]
+	_ = x[actSelect-127]
+	_ = x[actDeselect-128]
+	_ = x[actUnbind-129]
+	_ = x[actRebind-130]
+	_ = x[actToggleBind-131]
+	_ = x[actBecome-132]
+	_ = x[actShowHeader-133]
+	_ = x[actHideHeader-134]
+	_ = x[actBell-135]
+	_ = x[actExclude-136]
+	_ = x[actExcludeMulti-137]
 }
 
-const _actionType_name = "actIgnoreactStartactClickactInvalidactBracketedPasteBeginactBracketedPasteEndactCharactMouseactBeginningOfLineactAbortactAcceptactAcceptNonEmptyactAcceptOrPrintQueryactBackwardCharactBackwardDeleteCharactBackwardDeleteCharEofactBackwardWordactCancelactChangeBorderLabelactChangeListLabelactChangeInputLabelactChangeHeaderactChangeHeaderLabelactChangeMultiactChangePreviewLabelactChangePromptactChangeQueryactChangeNthactClearScreenactClearQueryactClearSelectionactCloseactDeleteCharactDeleteCharEofactEndOfLineactFatalactForwardCharactForwardWordactKillLineactKillWordactUnixLineDiscardactUnixWordRuboutactYankactBackwardKillWordactSelectAllactDeselectAllactToggleactToggleSearchactToggleAllactToggleDownactToggleUpactToggleInactToggleOutactToggleTrackactToggleTrackCurrentactToggleHeaderactToggleWrapactToggleMultiLineactToggleHscrollactTrackCurrentactToggleInputactHideInputactShowInputactUntrackCurrentactDownactUpactPageUpactPageDownactPositionactHalfPageUpactHalfPageDownactOffsetUpactOffsetDownactOffsetMiddleactJumpactJumpAcceptactPrintQueryactRefreshPreviewactReplaceQueryactToggleSortactShowPreviewactHidePreviewactTogglePreviewactTogglePreviewWrapactTransformactTransformBorderLabelactTransformListLabelactTransformInputLabelactTransformHeaderactTransformHeaderLabelactTransformNthactTransformPointeractTransformPreviewLabelactTransformPromptactTransformQueryactTransformSearchactSearchactPreviewactChangePointeractChangePreviewactChangePreviewWindowactPreviewTopactPreviewBottomactPreviewUpactPreviewDownactPreviewPageUpactPreviewPageDownactPreviewHalfPageUpactPreviewHalfPageDownactPrevHistoryactPrevSelectedactPrintactPutactNextHistoryactNextSelectedactExecuteactExecuteSilentactExecuteMultiactSigStopactFirstactLastactReloadactReloadSyncactDisableSearchactEnableSearchactSelectactDeselectactUnbindactRebindactToggleBindactBecomeactShowHeaderactHideHeaderactBellactExcludeactExcludeMulti"
+const _actionType_name = "actIgnoreactStartactClickactInvalidactBracketedPasteBeginactBracketedPasteEndactCharactMouseactBeginningOfLineactAbortactAcceptactAcceptNonEmptyactAcceptOrPrintQueryactBackwardCharactBackwardDeleteCharactBackwardDeleteCharEofactBackwardWordactCancelactChangeBorderLabelactChangeGhostactChangeHeaderactChangeHeaderLabelactChangeInputLabelactChangeListLabelactChangeMultiactChangeNthactChangePointeractChangePreviewactChangePreviewLabelactChangePreviewWindowactChangePromptactChangeQueryactClearScreenactClearQueryactClearSelectionactCloseactDeleteCharactDeleteCharEofactEndOfLineactFatalactForwardCharactForwardWordactKillLineactKillWordactUnixLineDiscardactUnixWordRuboutactYankactBackwardKillWordactSelectAllactDeselectAllactToggleactToggleSearchactToggleAllactToggleDownactToggleUpactToggleInactToggleOutactToggleTrackactToggleTrackCurrentactToggleHeaderactToggleWrapactToggleMultiLineactToggleHscrollactTrackCurrentactToggleInputactHideInputactShowInputactUntrackCurrentactDownactUpactPageUpactPageDownactPositionactHalfPageUpactHalfPageDownactOffsetUpactOffsetDownactOffsetMiddleactJumpactJumpAcceptactPrintQueryactRefreshPreviewactReplaceQueryactToggleSortactShowPreviewactHidePreviewactTogglePreviewactTogglePreviewWrapactTransformactTransformBorderLabelactTransformGhostactTransformHeaderactTransformHeaderLabelactTransformInputLabelactTransformListLabelactTransformNthactTransformPointeractTransformPreviewLabelactTransformPromptactTransformQueryactTransformSearchactSearchactPreviewactPreviewTopactPreviewBottomactPreviewUpactPreviewDownactPreviewPageUpactPreviewPageDownactPreviewHalfPageUpactPreviewHalfPageDownactPrevHistoryactPrevSelectedactPrintactPutactNextHistoryactNextSelectedactExecuteactExecuteSilentactExecuteMultiactSigStopactFirstactLastactReloadactReloadSyncactDisableSearchactEnableSearchactSelectactDeselectactUnbindactRebindactToggleBindactBecomeactShowHeaderactHideHeaderactBellactExcludeactExcludeMulti"
 
-var _actionType_index = [...]uint16{0, 9, 17, 25, 35, 57, 77, 84, 92, 110, 118, 127, 144, 165, 180, 201, 225, 240, 249, 269, 287, 306, 321, 341, 355, 376, 391, 405, 417, 431, 444, 461, 469, 482, 498, 510, 518, 532, 546, 557, 568, 586, 603, 610, 629, 641, 655, 664, 679, 691, 704, 715, 726, 738, 752, 773, 788, 801, 819, 835, 850, 864, 876, 888, 905, 912, 917, 926, 937, 948, 961, 976, 987, 1000, 1015, 1022, 1035, 1048, 1065, 1080, 1093, 1107, 1121, 1137, 1157, 1169, 1192, 1213, 1235, 1253, 1276, 1291, 1310, 1334, 1352, 1369, 1387, 1396, 1406, 1422, 1438, 1460, 1473, 1489, 1501, 1515, 1531, 1549, 1569, 1591, 1605, 1620, 1628, 1634, 1648, 1663, 1673, 1689, 1704, 1714, 1722, 1729, 1738, 1751, 1767, 1782, 1791, 1802, 1811, 1820, 1833, 1842, 1855, 1868, 1875, 1885, 1900}
+var _actionType_index = [...]uint16{0, 9, 17, 25, 35, 57, 77, 84, 92, 110, 118, 127, 144, 165, 180, 201, 225, 240, 249, 269, 283, 298, 318, 337, 355, 369, 381, 397, 413, 434, 456, 471, 485, 499, 512, 529, 537, 550, 566, 578, 586, 600, 614, 625, 636, 654, 671, 678, 697, 709, 723, 732, 747, 759, 772, 783, 794, 806, 820, 841, 856, 869, 887, 903, 918, 932, 944, 956, 973, 980, 985, 994, 1005, 1016, 1029, 1044, 1055, 1068, 1083, 1090, 1103, 1116, 1133, 1148, 1161, 1175, 1189, 1205, 1225, 1237, 1260, 1277, 1295, 1318, 1340, 1361, 1376, 1395, 1419, 1437, 1454, 1472, 1481, 1491, 1504, 1520, 1532, 1546, 1562, 1580, 1600, 1622, 1636, 1651, 1659, 1665, 1679, 1694, 1704, 1720, 1735, 1745, 1753, 1760, 1769, 1782, 1798, 1813, 1822, 1833, 1842, 1851, 1864, 1873, 1886, 1899, 1906, 1916, 1931}
 
 func (i actionType) String() string {
 	if i < 0 || i >= actionType(len(_actionType_index)-1) {
diff --git a/src/options.go b/src/options.go
index 80e428e3..c250fb59 100644
--- a/src/options.go
+++ b/src/options.go
@@ -1404,7 +1404,7 @@ const (
 
 func init() {
 	executeRegexp = regexp.MustCompile(
-		`(?si)[:+](become|execute(?:-multi|-silent)?|reload(?:-sync)?|preview|(?:change|transform)-(?:query|prompt|(?:border|list|preview|input|header)-label|header|search|nth|pointer)|transform|change-(?:preview-window|preview|multi)|(?:re|un|toggle-)bind|pos|put|print|search)`)
+		`(?si)[:+](become|execute(?:-multi|-silent)?|reload(?:-sync)?|preview|(?:change|transform)-(?:query|prompt|(?:border|list|preview|input|header)-label|header|search|nth|pointer|ghost)|transform|change-(?:preview-window|preview|multi)|(?:re|un|toggle-)bind|pos|put|print|search)`)
 	splitRegexp = regexp.MustCompile("[,:]+")
 	actionNameRegexp = regexp.MustCompile("(?i)^[a-z-]+")
 }
@@ -1799,6 +1799,8 @@ func isExecuteAction(str string) actionType {
 		return actChangeInputLabel
 	case "change-header-label":
 		return actChangeHeaderLabel
+	case "change-ghost":
+		return actChangeGhost
 	case "change-pointer":
 		return actChangePointer
 	case "change-preview-window":
@@ -1839,6 +1841,8 @@ func isExecuteAction(str string) actionType {
 		return actTransformHeaderLabel
 	case "transform-header":
 		return actTransformHeader
+	case "transform-ghost":
+		return actTransformGhost
 	case "transform-nth":
 		return actTransformNth
 	case "transform-pointer":
diff --git a/src/terminal.go b/src/terminal.go
index ad5ad628..8b4651c1 100644
--- a/src/terminal.go
+++ b/src/terminal.go
@@ -475,15 +475,19 @@ const (
 	actBackwardWord
 	actCancel
 	actChangeBorderLabel
-	actChangeListLabel
-	actChangeInputLabel
+	actChangeGhost
 	actChangeHeader
 	actChangeHeaderLabel
+	actChangeInputLabel
+	actChangeListLabel
 	actChangeMulti
+	actChangeNth
+	actChangePointer
+	actChangePreview
 	actChangePreviewLabel
+	actChangePreviewWindow
 	actChangePrompt
 	actChangeQuery
-	actChangeNth
 	actClearScreen
 	actClearQuery
 	actClearSelection
@@ -542,10 +546,11 @@ const (
 	actTogglePreviewWrap
 	actTransform
 	actTransformBorderLabel
-	actTransformListLabel
-	actTransformInputLabel
+	actTransformGhost
 	actTransformHeader
 	actTransformHeaderLabel
+	actTransformInputLabel
+	actTransformListLabel
 	actTransformNth
 	actTransformPointer
 	actTransformPreviewLabel
@@ -554,9 +559,6 @@ const (
 	actTransformSearch
 	actSearch
 	actPreview
-	actChangePointer
-	actChangePreview
-	actChangePreviewWindow
 	actPreviewTop
 	actPreviewBottom
 	actPreviewUp
@@ -5958,6 +5960,15 @@ func (t *Terminal) Loop() error {
 						}
 					}
 				}
+			case actChangeGhost, actTransformGhost:
+				ghost := a.a
+				if a.t == actTransformGhost {
+					ghost = t.captureLine(a.a)
+				}
+				t.ghost = ghost
+				if len(t.input) == 0 {
+					req(reqPrompt)
+				}
 			case actChangePointer, actTransformPointer:
 				pointer := a.a
 				if a.t == actTransformPointer {
diff --git a/test/test_core.rb b/test/test_core.rb
index c8b73f23..f8a182f8 100644
--- a/test/test_core.rb
+++ b/test/test_core.rb
@@ -1815,7 +1815,7 @@ class TestCore < TestInteractive
   end
 
   def test_ghost
-    tmux.send_keys %(seq 100 | #{FZF} --prompt 'X ' --ghost 'Type in query ...'), :Enter
+    tmux.send_keys %(seq 100 | #{FZF} --prompt 'X ' --ghost 'Type in query ...' --bind 'space:change-ghost:Y Z' --bind 'enter:transform-ghost:echo Z Y'), :Enter
     tmux.until do |lines|
       assert_equal 100, lines.match_count
       assert_includes lines, 'X Type in query ...'
@@ -1830,6 +1830,10 @@ class TestCore < TestInteractive
       assert_equal 100, lines.match_count
       assert_includes lines, 'X Type in query ...'
     end
+    tmux.send_keys :Space
+    tmux.until { |lines| assert_includes lines, 'X Y Z' }
+    tmux.send_keys :Enter
+    tmux.until { |lines| assert_includes lines, 'X Z Y' }
   end
 
   def test_ghost_inline