Add 'exclude' action for excluding current/selected items from the result (#4231)

Close #4185

man/man1/fzf.1

@@ -1601,6 +1601,7 @@ A key or an event can be bound to one or more of the following actions.
     \fBdown\fR                         \fIctrl\-j  ctrl\-n  down\fR
     \fBenable\-search\fR                (enable search functionality)
     \fBend\-of\-line\fR                  \fIctrl\-e  end\fR
+    \fBexclude\fR                      (exclude the current item or the selected items from the result)
     \fBexecute(...)\fR                 (see below for the details)
     \fBexecute\-silent(...)\fR          (see below for the details)
     \fBfirst\fR                        (move to the first match; same as \fBpos(1)\fR)

src/core.go

@@ -198,10 +198,26 @@ func Run(opts *Options) (int, error) {
 	inputRevision := revision{}
 	snapshotRevision := revision{}
 	patternCache := make(map[string]*Pattern)
+	denyMutex := sync.Mutex{}
+	denylist := make(map[int32]struct{})
+	clearDenylist := func() {
+		denyMutex.Lock()
+		if len(denylist) > 0 {
+			patternCache = make(map[string]*Pattern)
+		}
+		denylist = make(map[int32]struct{})
+		denyMutex.Unlock()
+	}
 	patternBuilder := func(runes []rune) *Pattern {
+		denyMutex.Lock()
+		denylistCopy := make(map[int32]struct{})
+		for k, v := range denylist {
+			denylistCopy[k] = v
+		}
+		denyMutex.Unlock()
 		return BuildPattern(cache, patternCache,
 			opts.Fuzzy, opts.FuzzyAlgo, opts.Extended, opts.Case, opts.Normalize, forward, withPos,
-			opts.Filter == nil, nth, opts.Delimiter, inputRevision, runes)
+			opts.Filter == nil, nth, opts.Delimiter, inputRevision, runes, denylistCopy)
 	}
 	matcher := NewMatcher(cache, patternBuilder, sort, opts.Tac, eventBox, inputRevision)
 
@@ -301,6 +317,9 @@ func Run(opts *Options) (int, error) {
 	var snapshot []*Chunk
 	var count int
 	restart := func(command commandSpec, environ []string) {
+		if !useSnapshot {
+			clearDenylist()
+		}
 		reading = true
 		chunkList.Clear()
 		itemIndex = 0
@@ -347,7 +366,8 @@ func Run(opts *Options) (int, error) {
 					} else {
 						reading = reading && evt == EvtReadNew
 					}
-					if useSnapshot && evt == EvtReadFin {
+					if useSnapshot && evt == EvtReadFin { // reload-sync
+						clearDenylist()
 						useSnapshot = false
 					}
 					if !useSnapshot {
@@ -378,9 +398,21 @@ func Run(opts *Options) (int, error) {
 						command = val.command
 						environ = val.environ
 						changed = val.changed
+						bump := false
+						if len(val.denylist) > 0 && val.revision.compatible(inputRevision) {
+							denyMutex.Lock()
+							for _, itemIndex := range val.denylist {
+								denylist[itemIndex] = struct{}{}
+							}
+							denyMutex.Unlock()
+							bump = true
+						}
 						if val.nth != nil {
 							// Change nth and clear caches
 							nth = *val.nth
+							bump = true
+						}
+						if bump {
 							patternCache = make(map[string]*Pattern)
 							cache.Clear()
 							inputRevision.bumpMinor()

src/options.go

@@ -1603,6 +1603,8 @@ func parseActionList(masked string, original string, prevActions []*action, putA
 			}
 		case "bell":
 			appendAction(actBell)
+		case "exclude":
+			appendAction(actExclude)
 		default:
 			t := isExecuteAction(specLower)
 			if t == actIgnore {

src/pattern.go

@@ -63,6 +63,7 @@ type Pattern struct {
 	revision      revision
 	procFun       map[termType]algo.Algo
 	cache         *ChunkCache
+	denylist      map[int32]struct{}
 }
 
 var _splitRegex *regexp.Regexp
@@ -73,7 +74,7 @@ func init() {
 
 // BuildPattern builds Pattern object from the given arguments
 func BuildPattern(cache *ChunkCache, patternCache map[string]*Pattern, fuzzy bool, fuzzyAlgo algo.Algo, extended bool, caseMode Case, normalize bool, forward bool,
-	withPos bool, cacheable bool, nth []Range, delimiter Delimiter, revision revision, runes []rune) *Pattern {
+	withPos bool, cacheable bool, nth []Range, delimiter Delimiter, revision revision, runes []rune, denylist map[int32]struct{}) *Pattern {
 
 	var asString string
 	if extended {
@@ -144,6 +145,7 @@ func BuildPattern(cache *ChunkCache, patternCache map[string]*Pattern, fuzzy boo
 		revision:      revision,
 		delimiter:     delimiter,
 		cache:         cache,
+		denylist:      denylist,
 		procFun:       make(map[termType]algo.Algo)}
 
 	ptr.cacheKey = ptr.buildCacheKey()
@@ -243,6 +245,9 @@ func parseTerms(fuzzy bool, caseMode Case, normalize bool, str string) []termSet
 
 // IsEmpty returns true if the pattern is effectively empty
 func (p *Pattern) IsEmpty() bool {
+	if len(p.denylist) > 0 {
+		return false
+	}
 	if !p.extended {
 		return len(p.text) == 0
 	}
@@ -296,6 +301,8 @@ func (p *Pattern) Match(chunk *Chunk, slab *util.Slab) []Result {
 func (p *Pattern) matchChunk(chunk *Chunk, space []Result, slab *util.Slab) []Result {
 	matches := []Result{}
 
+	if len(p.denylist) == 0 {
+		// Huge code duplication for minimizing unnecessary map lookups
 		if space == nil {
 			for idx := 0; idx < chunk.count; idx++ {
 				if match, _, _ := p.MatchItem(&chunk.items[idx], p.withPos, slab); match != nil {
@@ -312,6 +319,28 @@ func (p *Pattern) matchChunk(chunk *Chunk, space []Result, slab *util.Slab) []Re
 		return matches
 	}
 
+	if space == nil {
+		for idx := 0; idx < chunk.count; idx++ {
+			if _, prs := p.denylist[chunk.items[idx].Index()]; prs {
+				continue
+			}
+			if match, _, _ := p.MatchItem(&chunk.items[idx], p.withPos, slab); match != nil {
+				matches = append(matches, *match)
+			}
+		}
+	} else {
+		for _, result := range space {
+			if _, prs := p.denylist[result.item.Index()]; prs {
+				continue
+			}
+			if match, _, _ := p.MatchItem(result.item, p.withPos, slab); match != nil {
+				matches = append(matches, *match)
+			}
+		}
+	}
+	return matches
+}
+
 // MatchItem returns true if the Item is a match
 func (p *Pattern) MatchItem(item *Item, withPos bool, slab *util.Slab) (*Result, []Offset, *[]int) {
 	if p.extended {

src/pattern_test.go

@@ -68,7 +68,7 @@ func buildPattern(fuzzy bool, fuzzyAlgo algo.Algo, extended bool, caseMode Case,
 	withPos bool, cacheable bool, nth []Range, delimiter Delimiter, runes []rune) *Pattern {
 	return BuildPattern(NewChunkCache(), make(map[string]*Pattern),
 		fuzzy, fuzzyAlgo, extended, caseMode, normalize, forward,
-		withPos, cacheable, nth, delimiter, revision{}, runes)
+		withPos, cacheable, nth, delimiter, revision{}, runes, nil)
 }
 
 func TestExact(t *testing.T) {

src/terminal.go

@@ -584,6 +584,7 @@ const (
 	actShowHeader
 	actHideHeader
 	actBell
+	actExclude
 )
 
 func (a actionType) Name() string {
@@ -627,6 +628,8 @@ type searchRequest struct {
 	command  *commandSpec
 	environ  []string
 	changed  bool
+	denylist []int32
+	revision revision
 }
 
 type previewRequest struct {
@@ -4751,6 +4754,7 @@ func (t *Terminal) Loop() error {
 		changed := false
 		beof := false
 		queryChanged := false
+		denylist := []int32{}
 
 		// Special handling of --sync. Activate the interface on the second tick.
 		if loopIndex == 1 && t.deferActivation() {
@@ -4907,6 +4911,21 @@ func (t *Terminal) Loop() error {
 				}
 			case actBell:
 				t.tui.Bell()
+			case actExclude:
+				if len(t.selected) > 0 {
+					for _, item := range t.sortSelected() {
+						denylist = append(denylist, item.item.Index())
+					}
+					// Clear selected items
+					t.selected = make(map[int32]selectedItem)
+					t.version++
+				} else {
+					item := t.currentItem()
+					if item != nil {
+						denylist = append(denylist, item.Index())
+					}
+				}
+				changed = true
 			case actExecute, actExecuteSilent:
 				t.executeCommand(a.a, false, a.t == actExecuteSilent, false, false, "")
 			case actExecuteMulti:
@@ -6016,7 +6035,7 @@ func (t *Terminal) Loop() error {
 		reload := changed || newCommand != nil
 		var reloadRequest *searchRequest
 		if reload {
-			reloadRequest = &searchRequest{sort: t.sort, sync: reloadSync, nth: newNth, command: newCommand, environ: t.environ(), changed: changed}
+			reloadRequest = &searchRequest{sort: t.sort, sync: reloadSync, nth: newNth, command: newCommand, environ: t.environ(), changed: changed, denylist: denylist, revision: t.merger.Revision()}
 		}
 		t.mutex.Unlock() // Must be unlocked before touching reqBox
 

test/test_core.rb

@@ -1666,6 +1666,30 @@ class TestCore < TestInteractive
     end
   end
 
+  def test_exclude
+    tmux.send_keys %(seq 1000 | #{FZF} --multi --bind 'a:exclude,b:reload(seq 1000),c:reload-sync(seq 1000)'), :Enter
+
+    tmux.until { |lines| assert_equal 1000, lines.match_count }
+    tmux.until { |lines| assert_includes lines, '> 1' }
+    tmux.send_keys :a
+    tmux.until { |lines| assert_includes lines, '> 2' }
+    tmux.until { |lines| assert_equal 999, lines.match_count }
+    tmux.send_keys :Up, :BTab, :BTab, :BTab, :a
+    tmux.until { |lines| assert_equal 996, lines.match_count }
+    tmux.until { |lines| assert_includes lines, '> 9' }
+    tmux.send_keys :b
+    tmux.until { |lines| assert_equal 1000, lines.match_count }
+    tmux.until { |lines| assert_includes lines, '> 5' }
+    tmux.send_keys :Tab, :Tab, :Tab, :a
+    tmux.until { |lines| assert_equal 997, lines.match_count }
+    tmux.until { |lines| assert_includes lines, '> 2' }
+    tmux.send_keys :c
+    tmux.until { |lines| assert_equal 1000, lines.match_count }
+    tmux.until { |lines| assert_includes lines, '> 2' }
+
+    # TODO: We should also check the behavior of 'exclude' during reloads
+  end
+
   def test_accept_nth
     tmux.send_keys %((echo "foo  bar  baz"; echo "bar baz  foo") | #{FZF} --multi --accept-nth 2,2 --sync --bind start:select-all+accept > #{tempname}), :Enter
     wait do