Add {*} placeholder flag

4 files changed, 70 insertions, 41 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4a8cb3a7..6bfb9427 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,11 @@ CHANGELOG
 
 0.63.0
 ------
+- Added `{*}` placeholder flag that evaluates to all matched items.
+  ```bash
+  seq 10000 | fzf --preview "awk '{sum += \$1} END {print sum}' {*f}"
+  ```
+  - Use this with caution, as it can make fzf sluggish for large lists.
 - Added background variants of transform actions with `bg-` prefix that run asynchronously in the background
   ```sh
   GETTER='curl -s http://metaphorpsum.com/sentences/1'
diff --git a/man/man1/fzf.1 b/man/man1/fzf.1
index a64b5e0d..df2fba5f 100644
--- a/man/man1/fzf.1
+++ b/man/man1/fzf.1
@@ -789,13 +789,16 @@ fzf also exports \fB$FZF_PREVIEW_TOP\fR and \fB$FZF_PREVIEW_LEFT\fR so that
 the preview command can determine the position of the preview window.
 
 A placeholder expression starting with \fB+\fR flag will be replaced to the
-space-separated list of the selected lines (or the current line if no selection
+space-separated list of the selected items (or the current item if no selection
 was made) individually quoted.
 
 e.g.
      \fBfzf \-\-multi \-\-preview='head \-10 {+}'
      git log \-\-oneline | fzf \-\-multi \-\-preview 'git show {+1}'\fR
 
+Similarly, a placeholder expression starting with \fB*\fR flag will be replaced
+to the space-separated list of all matched items individually quoted.
+
 Each expression expands to a quoted string, so that it's safe to pass it as an
 argument to an external command. So you should not manually add quotes around
 the curly braces. But if you don't want this behavior, you can put
@@ -807,14 +810,13 @@ from the replacement string. To preserve the whitespace, use the \fBs\fR flag.
 
 A placeholder expression with \fBf\fR flag is replaced to the path of
 a temporary file that holds the evaluated list. This is useful when you
-multi-select a large number of items and the length of the evaluated string may
+pass a large number of items and the length of the evaluated string may
 exceed \fBARG_MAX\fR.
 
 e.g.
-     \fB# Press CTRL\-A to select 100K items and see the sum of all the numbers.
+     \fB# See the sum of all the matched numbers
      # This won't work properly without 'f' flag due to ARG_MAX limit.
-     seq 100000 | fzf \-\-multi \-\-bind ctrl\-a:select\-all \\
-                      \-\-preview "awk '{sum+=\\$1} END {print sum}' {+f}"\fR
+     seq 100000 | fzf \-\-preview "awk '{sum+=\\$1} END {print sum}' {*f}"\fR
 
 Also,
 
diff --git a/src/terminal.go b/src/terminal.go
index 85a51112..fe33b340 100644
--- a/src/terminal.go
+++ b/src/terminal.go
@@ -66,7 +66,7 @@ const maxFocusEvents = 10000
 const blockDuration = 1 * time.Second
 
 func init() {
-	placeholder = regexp.MustCompile(`\\?(?:{[+sfr]*[0-9,-.]*}|{q(?::s?[0-9,-.]+)?}|{fzf:(?:query|action|prompt)}|{\+?f?nf?})`)
+	placeholder = regexp.MustCompile(`\\?(?:{[+*sfr]*[0-9,-.]*}|{q(?::s?[0-9,-.]+)?}|{fzf:(?:query|action|prompt)}|{\+?f?nf?})`)
 	whiteSuffix = regexp.MustCompile(`\s*$`)
 	offsetComponentRegex = regexp.MustCompile(`([+-][0-9]+)|(-?/[1-9][0-9]*)`)
 	offsetTrimCharsRegex = regexp.MustCompile(`[^0-9/+-]`)
@@ -692,6 +692,7 @@ func processExecution(action actionType) bool {
 
 type placeholderFlags struct {
 	plus          bool
+	asterisk      bool
 	preserveSpace bool
 	number        bool
 	forceUpdate   bool
@@ -713,7 +714,7 @@ type searchRequest struct {
 type previewRequest struct {
 	template     string
 	scrollOffset int
-	list         []*Item
+	list         [3][]*Item
 	env          []string
 	query        string
 }
@@ -4099,6 +4100,8 @@ func parsePlaceholder(match string) (bool, string, placeholderFlags) {
 	trimmed := ""
 	for _, char := range match[1:] {
 		switch char {
+		case '*':
+			flags.asterisk = true
 		case '+':
 			flags.plus = true
 		case 's':
@@ -4122,19 +4125,16 @@ func parsePlaceholder(match string) (bool, string, placeholderFlags) {
 	return false, matchWithoutFlags, flags
 }
 
-func hasPreviewFlags(template string) (slot bool, plus bool, forceUpdate bool) {
+func hasPreviewFlags(template string) (slot bool, plus bool, asterisk bool, forceUpdate bool) {
 	for _, match := range placeholder.FindAllString(template, -1) {
 		escaped, _, flags := parsePlaceholder(match)
 		if escaped {
 			continue
 		}
-		if flags.plus {
-			plus = true
-		}
-		if flags.forceUpdate {
-			forceUpdate = true
-		}
 		slot = true
+		plus = plus || flags.plus
+		asterisk = asterisk || flags.asterisk
+		forceUpdate = forceUpdate || flags.forceUpdate
 	}
 	return
 }
@@ -4146,17 +4146,17 @@ type replacePlaceholderParams struct {
 	printsep   string
 	forcePlus  bool
 	query      string
-	allItems   []*Item
+	allItems   [3][]*Item // current, select, and all matched items
 	lastAction actionType
 	prompt     string
 	executor   *util.Executor
 }
 
 func (t *Terminal) replacePlaceholderInInitialCommand(template string) (string, []string) {
-	return t.replacePlaceholder(template, false, string(t.input), []*Item{nil, nil})
+	return t.replacePlaceholder(template, false, string(t.input), [3][]*Item{nil, nil, nil})
 }
 
-func (t *Terminal) replacePlaceholder(template string, forcePlus bool, input string, list []*Item) (string, []string) {
+func (t *Terminal) replacePlaceholder(template string, forcePlus bool, input string, list [3][]*Item) (string, []string) {
 	return replacePlaceholder(replacePlaceholderParams{
 		template:   template,
 		stripAnsi:  t.ansi,
@@ -4177,7 +4177,7 @@ func (t *Terminal) evaluateScrollOffset() int {
 	}
 
 	// We only need the current item to calculate the scroll offset
-	replaced, tempFiles := t.replacePlaceholder(t.activePreviewOpts.scroll, false, "", []*Item{t.currentItem(), nil})
+	replaced, tempFiles := t.replacePlaceholder(t.activePreviewOpts.scroll, false, "", [3][]*Item{{t.currentItem()}, nil, nil})
 	removeFiles(tempFiles)
 	offsetExpr := offsetTrimCharsRegex.ReplaceAllString(replaced, "")
 
@@ -4209,14 +4209,9 @@ func (t *Terminal) evaluateScrollOffset() int {
 
 func replacePlaceholder(params replacePlaceholderParams) (string, []string) {
 	tempFiles := []string{}
-	current := params.allItems[:1]
-	selected := params.allItems[1:]
-	if current[0] == nil {
-		current = []*Item{}
-	}
-	if selected[0] == nil {
-		selected = []*Item{}
-	}
+	current := params.allItems[0]
+	selected := params.allItems[1]
+	matched := params.allItems[2]
 
 	// replace placeholders one by one
 	replaced := placeholder.ReplaceAllStringFunc(params.template, func(match string) string {
@@ -4312,7 +4307,9 @@ func replacePlaceholder(params replacePlaceholderParams) (string, []string) {
 		// apply 'replace' function over proper set of items and return result
 
 		items := current
-		if flags.plus || params.forcePlus {
+		if flags.asterisk {
+			items = matched
+		} else if flags.plus || params.forcePlus {
 			items = selected
 		}
 		replacements := make([]string, len(items))
@@ -4546,11 +4543,15 @@ func (t *Terminal) currentItem() *Item {
 	return nil
 }
 
-func (t *Terminal) buildPlusList(template string, forcePlus bool) (bool, []*Item) {
+func (t *Terminal) buildPlusList(template string, forcePlus bool) (bool, [3][]*Item) {
 	current := t.currentItem()
-	slot, plus, forceUpdate := hasPreviewFlags(template)
-	if !(!slot || forceUpdate || (forcePlus || plus) && len(t.selected) > 0) {
-		return current != nil, []*Item{current, current}
+	slot, plus, asterisk, forceUpdate := hasPreviewFlags(template)
+	if !(!slot || forceUpdate || asterisk || (forcePlus || plus) && len(t.selected) > 0) {
+		if current == nil {
+			// Invalid
+			return false, [3][]*Item{nil, nil, nil}
+		}
+		return true, [3][]*Item{{current}, {current}, nil}
 	}
 
 	// We would still want to update preview window even if there is no match if
@@ -4561,17 +4562,26 @@ func (t *Terminal) buildPlusList(template string, forcePlus bool) (bool, []*Item
 		current = &minItem
 	}
 
+	var all []*Item
+	if asterisk {
+		cnt := t.merger.Length()
+		all = make([]*Item, cnt)
+		for i := 0; i < cnt; i++ {
+			item := t.merger.Get(i).item
+			all[i] = item
+		}
+	}
+
 	var sels []*Item
 	if len(t.selected) == 0 {
-		sels = []*Item{current, current}
-	} else {
-		sels = make([]*Item, len(t.selected)+1)
-		sels[0] = current
+		sels = []*Item{current}
+	} else if len(t.selected) > 0 {
+		sels = make([]*Item, len(t.selected))
 		for i, sel := range t.sortSelected() {
-			sels[i+1] = sel.item
+			sels[i] = sel.item
 		}
 	}
-	return true, sels
+	return true, [3][]*Item{{current}, sels, all}
 }
 
 func (t *Terminal) selectItem(item *Item) bool {
@@ -4831,7 +4841,8 @@ func (t *Terminal) Loop() error {
 			stop := false
 			t.previewBox.WaitFor(reqPreviewReady)
 			for {
-				var items []*Item
+				requested := false
+				var items [3][]*Item
 				var commandTemplate string
 				var env []string
 				var query string
@@ -4849,6 +4860,7 @@ func (t *Terminal) Loop() error {
 							items = request.list
 							env = request.env
 							query = request.query
+							requested = true
 						}
 					}
 					events.Clear()
@@ -4856,7 +4868,7 @@ func (t *Terminal) Loop() error {
 				if stop {
 					break
 				}
-				if items == nil {
+				if !requested {
 					continue
 				}
 				version++
@@ -6396,7 +6408,7 @@ func (t *Terminal) Loop() error {
 					// We run the command even when there's no match
 					// 1. If the template doesn't have any slots
 					// 2. If the template has {q}
-					slot, _, forceUpdate := hasPreviewFlags(a.a)
+					slot, _, _, forceUpdate := hasPreviewFlags(a.a)
 					valid = !slot || forceUpdate
 				}
 				if valid {
@@ -6585,7 +6597,7 @@ func (t *Terminal) Loop() error {
 		}
 
 		if queryChanged && t.canPreview() && len(t.previewOpts.command) > 0 {
-			_, _, forceUpdate := hasPreviewFlags(t.previewOpts.command)
+			_, _, _, forceUpdate := hasPreviewFlags(t.previewOpts.command)
 			if forceUpdate {
 				t.version++
 			}
diff --git a/test/test_preview.rb b/test/test_preview.rb
index 576e36ec..e2147735 100644
--- a/test/test_preview.rb
+++ b/test/test_preview.rb
@@ -189,6 +189,16 @@ class TestPreview < TestInteractive
     tmux.until { |lines| assert_includes lines[1], ' {//1 10/1   10  /123//0 9} ' }
   end
 
+  def test_preview_asterisk
+    tmux.send_keys %(seq 5 | #{FZF} --multi --preview 'echo {} / {+} / {*}'), :Enter
+    tmux.until { |lines| assert_equal 5, lines.match_count }
+    tmux.until { |lines| assert_includes lines[1], ' 1 / 1 / 1 2 3 4 5 ' }
+    tmux.send_keys :BTab
+    tmux.until { |lines| assert_includes lines[1], ' 2 / 1 / 1 2 3 4 5 ' }
+    tmux.send_keys :BTab
+    tmux.until { |lines| assert_includes lines[1], ' 3 / 1 2 / 1 2 3 4 5 ' }
+  end
+
   def test_preview_file
     tmux.send_keys %[(echo foo bar; echo bar foo) | #{FZF} --multi --preview 'cat {+f} {+f2} {+nf} {+fn}' --print0], :Enter
     tmux.until { |lines| assert_includes lines[1], ' foo barbar00 ' }