ADD $FZF_DIRECTION

CHANGELOG.md

@@ -132,6 +132,20 @@ fzf --gutter ' ' --color gutter:reverse
 
 As noted above, the `--gutter-raw CHAR` option was also added for customizing the gutter column in raw mode.
 
+### Added environment variable
+
+`$FZF_DIRECTION` is now exported to child processes, indicating the list direction of the current layout.
+
+- `up` for the default layout
+- `down` for `reverse` or `reverse-list`
+
+This simplifies writing transform actions involving layout-dependent actions
+like `{up,down}-match`, `{up,down}-selected`, and `toggle+{up,down}`.
+
+```sh
+fzf --raw --bind 'result:first+transform:[[ $FZF_RAW = 0 ]] && echo $FZF_DIRECTION-match'
+```
+
 ### Breaking changes
 
 #### Hiding the gutter column

man/man1/fzf.1

@@ -1335,6 +1335,8 @@ fzf exports the following environment variables to its child processes.
 .br
 .BR FZF_COLUMNS "         Number of columns fzf takes up excluding padding and margin"
 .br
+.BR FZF_DIRECTION "       Direction of the list (\fBup\fR or \fBdown\fR)"
+.br
 .BR FZF_TOTAL_COUNT "     Total number of items"
 .br
 .BR FZF_MATCH_COUNT "     Number of matched items"

src/terminal.go

@@ -1307,6 +1307,11 @@ func (t *Terminal) environImpl(forPreview bool) []string {
 	env = append(env, "FZF_LIST_LABEL="+t.listLabelOpts.label)
 	env = append(env, "FZF_INPUT_LABEL="+t.inputLabelOpts.label)
 	env = append(env, "FZF_HEADER_LABEL="+t.headerLabelOpts.label)
+	direction := "down"
+	if t.layout == layoutDefault {
+		direction = "up"
+	}
+	env = append(env, "FZF_DIRECTION="+direction)
 	if len(t.nthCurrent) > 0 {
 		env = append(env, "FZF_NTH="+RangesToString(t.nthCurrent))
 	}

test/test_core.rb

@@ -1682,6 +1682,7 @@ class TestCore < TestInteractive
 
     tmux.send_keys %(seq 100 | #{FZF} --multi --reverse --preview-window 0 --preview 'env | grep ^FZF_ | sort > #{tempname}' --no-input --bind enter:show-input+refresh-preview,space:disable-search+refresh-preview), :Enter
     expected = {
+      FZF_DIRECTION: 'down',
       FZF_TOTAL_COUNT: '100',
       FZF_MATCH_COUNT: '100',
       FZF_SELECT_COUNT: '0',