Remove pointer indirection by changing Chunk definition

src/chunklist.go

@@ -2,12 +2,12 @@ package fzf
 
 import "sync"
 
-// Chunk is a list of Item pointers whose size has the upper limit of chunkSize
-type Chunk []*Item // >>> []Item
+// Chunk is a list of Items whose size has the upper limit of chunkSize
+type Chunk []Item
 
 // ItemBuilder is a closure type that builds Item object from a pointer to a
 // string and an integer
-type ItemBuilder func([]byte, int) *Item
+type ItemBuilder func([]byte, int) Item
 
 // ChunkList is a list of Chunks
 type ChunkList struct {
@@ -28,11 +28,11 @@ func NewChunkList(trans ItemBuilder) *ChunkList {
 
 func (c *Chunk) push(trans ItemBuilder, data []byte, index int) bool {
 	item := trans(data, index)
-	if item != nil {
-		*c = append(*c, item)
-		return true
+	if item.Nil() {
+		return false
 	}
-	return false
+	*c = append(*c, item)
+	return true
 }
 
 // IsFull returns true if the Chunk is full
@@ -58,7 +58,7 @@ func (cl *ChunkList) Push(data []byte) bool {
 	defer cl.mutex.Unlock()
 
 	if len(cl.chunks) == 0 || cl.lastChunk().IsFull() {
-		newChunk := Chunk(make([]*Item, 0, chunkSize))
+		newChunk := Chunk(make([]Item, 0, chunkSize))
 		cl.chunks = append(cl.chunks, &newChunk)
 	}
 

src/chunklist_test.go

@@ -11,8 +11,8 @@ func TestChunkList(t *testing.T) {
 	// FIXME global
 	sortCriteria = []criterion{byScore, byLength}
 
-	cl := NewChunkList(func(s []byte, i int) *Item {
-		return &Item{text: util.ToChars(s), index: int32(i * 2)}
+	cl := NewChunkList(func(s []byte, i int) Item {
+		return Item{text: util.ToChars(s), index: int32(i * 2)}
 	})
 
 	// Snapshot

src/core.go

@@ -91,27 +91,27 @@ func Run(opts *Options, revision string) {
 	var chunkList *ChunkList
 	header := make([]string, 0, opts.HeaderLines)
 	if len(opts.WithNth) == 0 {
-		chunkList = NewChunkList(func(data []byte, index int) *Item {
+		chunkList = NewChunkList(func(data []byte, index int) Item {
 			if len(header) < opts.HeaderLines {
 				header = append(header, string(data))
 				eventBox.Set(EvtHeader, header)
-				return nil
+				return nilItem
 			}
 			chars, colors := ansiProcessor(data)
-			return &Item{
+			return Item{
 				index:      int32(index),
 				trimLength: -1,
 				text:       chars,
 				colors:     colors}
 		})
 	} else {
-		chunkList = NewChunkList(func(data []byte, index int) *Item {
+		chunkList = NewChunkList(func(data []byte, index int) Item {
 			tokens := Tokenize(util.ToChars(data), opts.Delimiter)
 			trans := Transform(tokens, opts.WithNth)
 			if len(header) < opts.HeaderLines {
 				header = append(header, string(joinTokens(trans)))
 				eventBox.Set(EvtHeader, header)
-				return nil
+				return nilItem
 			}
 			textRunes := joinTokens(trans)
 			item := Item{
@@ -123,7 +123,7 @@ func Run(opts *Options, revision string) {
 			trimmed, colors := ansiProcessorRunes(textRunes)
 			item.text = trimmed
 			item.colors = colors
-			return &item
+			return item
 		})
 	}
 
@@ -168,8 +168,8 @@ func Run(opts *Options, revision string) {
 			reader := Reader{
 				func(runes []byte) bool {
 					item := chunkList.trans(runes, 0)
-					if item != nil {
-						if result, _, _ := pattern.MatchItem(item, false, slab); result != nil {
+					if !item.Nil() {
+						if result, _, _ := pattern.MatchItem(&item, false, slab); result != nil {
 							opts.Printer(item.text.ToString())
 							found = true
 						}

src/item.go

@@ -19,6 +19,12 @@ func (item *Item) Index() int32 {
 	return item.index
 }
 
+var nilItem = Item{index: -1}
+
+func (item *Item) Nil() bool {
+	return item.index < 0
+}
+
 func (item *Item) TrimLength() int32 {
 	if item.trimLength >= 0 {
 		return item.trimLength

src/merger.go

@@ -65,7 +65,7 @@ func (mg *Merger) Get(idx int) *Result {
 			idx = mg.count - idx - 1
 		}
 		chunk := (*mg.chunks)[idx/chunkSize]
-		return &Result{item: (*chunk)[idx%chunkSize]}
+		return &Result{item: &(*chunk)[idx%chunkSize]}
 	}
 
 	if mg.sorted {

src/pattern.go

@@ -281,8 +281,8 @@ func (p *Pattern) matchChunk(chunk *Chunk, space []*Result, slab *util.Slab) []*
 	matches := []*Result{}
 
 	if space == nil {
-		for _, item := range *chunk {
-			if match, _, _ := p.MatchItem(item, false, slab); match != nil {
+		for idx := range *chunk {
+			if match, _, _ := p.MatchItem(&(*chunk)[idx], false, slab); match != nil {
 				matches = append(matches, match)
 			}
 		}

src/pattern_test.go

@@ -139,7 +139,7 @@ func TestOrigTextAndTransformed(t *testing.T) {
 	origBytes := []byte("junegunn.choi")
 	for _, extended := range []bool{false, true} {
 		chunk := Chunk{
-			&Item{
+			Item{
 				text:        util.RunesToChars([]rune("junegunn")),
 				origText:    &origBytes,
 				transformed: trans},
@@ -152,7 +152,7 @@ func TestOrigTextAndTransformed(t *testing.T) {
 			t.Error("Invalid match result", matches)
 		}
 
-		match, offsets, pos := pattern.MatchItem(chunk[0], true, slab)
+		match, offsets, pos := pattern.MatchItem(&chunk[0], true, slab)
 		if !(match.item.text.ToString() == "junegunn" &&
 			string(*match.item.origText) == "junegunn.choi" &&
 			offsets[0][0] == 0 && offsets[0][1] == 5 &&