Consolidate Result and rank structs

By not storing item index twice, we can cut down the size of Result
struct and now it makes more sense to store and pass Results by values.
Benchmarks show no degradation of performance by additional pointer
indirection for looking up index.

src/cache.go

@@ -3,7 +3,7 @@ package fzf
 import "sync"
 
 // queryCache associates strings to lists of items
-type queryCache map[string][]*Result
+type queryCache map[string][]Result
 
 // ChunkCache associates Chunk and query string to lists of items
 type ChunkCache struct {
@@ -17,7 +17,7 @@ func NewChunkCache() ChunkCache {
 }
 
 // Add adds the list to the cache
-func (cc *ChunkCache) Add(chunk *Chunk, key string, list []*Result) {
+func (cc *ChunkCache) Add(chunk *Chunk, key string, list []Result) {
 	if len(key) == 0 || !chunk.IsFull() || len(list) > queryCacheMax {
 		return
 	}
@@ -34,7 +34,7 @@ func (cc *ChunkCache) Add(chunk *Chunk, key string, list []*Result) {
 }
 
 // Lookup is called to lookup ChunkCache
-func (cc *ChunkCache) Lookup(chunk *Chunk, key string) []*Result {
+func (cc *ChunkCache) Lookup(chunk *Chunk, key string) []Result {
 	if len(key) == 0 || !chunk.IsFull() {
 		return nil
 	}
@@ -52,7 +52,7 @@ func (cc *ChunkCache) Lookup(chunk *Chunk, key string) []*Result {
 	return nil
 }
 
-func (cc *ChunkCache) Search(chunk *Chunk, key string) []*Result {
+func (cc *ChunkCache) Search(chunk *Chunk, key string) []Result {
 	if len(key) == 0 || !chunk.IsFull() {
 		return nil
 	}

src/cache_test.go

@@ -7,8 +7,8 @@ func TestChunkCache(t *testing.T) {
 	chunk2 := make(Chunk, chunkSize)
 	chunk1p := &Chunk{}
 	chunk2p := &chunk2
-	items1 := []*Result{&Result{}}
+	items1 := []Result{Result{}}
-	items2 := []*Result{&Result{}, &Result{}}
+	items2 := []Result{Result{}, Result{}}
 	cache.Add(chunk1p, "foo", items1)
 	cache.Add(chunk2p, "foo", items1)
 	cache.Add(chunk2p, "bar", items2)

src/matcher.go

@@ -131,7 +131,7 @@ func (m *Matcher) sliceChunks(chunks []*Chunk) [][]*Chunk {
 
 type partialResult struct {
 	index   int
-	matches []*Result
+	matches []Result
 }
 
 func (m *Matcher) scan(request MatchRequest) (*Merger, bool) {
@@ -162,7 +162,7 @@ func (m *Matcher) scan(request MatchRequest) (*Merger, bool) {
 		go func(idx int, slab *util.Slab, chunks []*Chunk) {
 			defer func() { waitGroup.Done() }()
 			count := 0
-			allMatches := make([][]*Result, len(chunks))
+			allMatches := make([][]Result, len(chunks))
 			for idx, chunk := range chunks {
 				matches := request.pattern.Match(chunk, slab)
 				allMatches[idx] = matches
@@ -172,7 +172,7 @@ func (m *Matcher) scan(request MatchRequest) (*Merger, bool) {
 				}
 				countChan <- len(matches)
 			}
-			sliceMatches := make([]*Result, 0, count)
+			sliceMatches := make([]Result, 0, count)
 			for _, matches := range allMatches {
 				sliceMatches = append(sliceMatches, matches...)
 			}
@@ -212,7 +212,7 @@ func (m *Matcher) scan(request MatchRequest) (*Merger, bool) {
 		}
 	}
 
-	partialResults := make([][]*Result, numSlices)
+	partialResults := make([][]Result, numSlices)
 	for _ = range slices {
 		partialResult := <-resultChan
 		partialResults[partialResult.index] = partialResult.matches

src/merger.go

@@ -3,14 +3,14 @@ package fzf
 import "fmt"
 
 // EmptyMerger is a Merger with no data
-var EmptyMerger = NewMerger(nil, [][]*Result{}, false, false)
+var EmptyMerger = NewMerger(nil, [][]Result{}, false, false)
 
 // Merger holds a set of locally sorted lists of items and provides the view of
 // a single, globally-sorted list
 type Merger struct {
 	pattern *Pattern
-	lists   [][]*Result
+	lists   [][]Result
-	merged  []*Result
+	merged  []Result
 	chunks  *[]*Chunk
 	cursors []int
 	sorted  bool
@@ -35,11 +35,11 @@ func PassMerger(chunks *[]*Chunk, tac bool) *Merger {
 }
 
 // NewMerger returns a new Merger
-func NewMerger(pattern *Pattern, lists [][]*Result, sorted bool, tac bool) *Merger {
+func NewMerger(pattern *Pattern, lists [][]Result, sorted bool, tac bool) *Merger {
 	mg := Merger{
 		pattern: pattern,
 		lists:   lists,
-		merged:  []*Result{},
+		merged:  []Result{},
 		chunks:  nil,
 		cursors: make([]int, len(lists)),
 		sorted:  sorted,
@@ -59,13 +59,13 @@ func (mg *Merger) Length() int {
 }
 
 // Get returns the pointer to the Result object indexed by the given integer
-func (mg *Merger) Get(idx int) *Result {
+func (mg *Merger) Get(idx int) Result {
 	if mg.chunks != nil {
 		if mg.tac {
 			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 {
@@ -89,7 +89,7 @@ func (mg *Merger) cacheable() bool {
 	return mg.count < mergerCacheMax
 }
 
-func (mg *Merger) mergedGet(idx int) *Result {
+func (mg *Merger) mergedGet(idx int) Result {
 	for i := len(mg.merged); i <= idx; i++ {
 		minRank := minRank()
 		minIdx := -1
@@ -100,7 +100,7 @@ func (mg *Merger) mergedGet(idx int) *Result {
 				continue
 			}
 			if cursor >= 0 {
-				rank := list[cursor].rank
+				rank := list[cursor]
 				if minIdx < 0 || compareRanks(rank, minRank, mg.tac) {
 					minRank = rank
 					minIdx = listIdx

src/merger_test.go

@@ -15,11 +15,11 @@ func assert(t *testing.T, cond bool, msg ...string) {
 	}
 }
 
-func randResult() *Result {
+func randResult() Result {
 	str := fmt.Sprintf("%d", rand.Uint32())
-	return &Result{
+	chars := util.RunesToChars([]rune(str))
-		item: &Item{text: util.RunesToChars([]rune(str))},
+	chars.Index = rand.Int31()
-		rank: rank{index: rand.Int31()}}
+	return Result{item: &Item{text: chars}}
 }
 
 func TestEmptyMerger(t *testing.T) {
@@ -29,14 +29,14 @@ func TestEmptyMerger(t *testing.T) {
 	assert(t, len(EmptyMerger.merged) == 0, "Invalid merged list")
 }
 
-func buildLists(partiallySorted bool) ([][]*Result, []*Result) {
+func buildLists(partiallySorted bool) ([][]Result, []Result) {
 	numLists := 4
-	lists := make([][]*Result, numLists)
+	lists := make([][]Result, numLists)
 	cnt := 0
 	for i := 0; i < numLists; i++ {
 		numResults := rand.Int() % 20
 		cnt += numResults
-		lists[i] = make([]*Result, numResults)
+		lists[i] = make([]Result, numResults)
 		for j := 0; j < numResults; j++ {
 			item := randResult()
 			lists[i][j] = item
@@ -45,7 +45,7 @@ func buildLists(partiallySorted bool) ([][]*Result, []*Result) {
 			sort.Sort(ByRelevance(lists[i]))
 		}
 	}
-	items := []*Result{}
+	items := []Result{}
 	for _, list := range lists {
 		items = append(items, list...)
 	}

src/pattern.go

@@ -243,7 +243,7 @@ func (p *Pattern) CacheKey() string {
 }
 
 // Match returns the list of matches Items in the given Chunk
-func (p *Pattern) Match(chunk *Chunk, slab *util.Slab) []*Result {
+func (p *Pattern) Match(chunk *Chunk, slab *util.Slab) []Result {
 	// ChunkCache: Exact match
 	cacheKey := p.CacheKey()
 	if p.cacheable {
@@ -263,19 +263,19 @@ func (p *Pattern) Match(chunk *Chunk, slab *util.Slab) []*Result {
 	return matches
 }
 
-func (p *Pattern) matchChunk(chunk *Chunk, space []*Result, slab *util.Slab) []*Result {
+func (p *Pattern) matchChunk(chunk *Chunk, space []Result, slab *util.Slab) []Result {
-	matches := []*Result{}
+	matches := []Result{}
 
 	if space == nil {
 		for idx := range *chunk {
 			if match, _, _ := p.MatchItem(&(*chunk)[idx], false, slab); match != nil {
-				matches = append(matches, match)
+				matches = append(matches, *match)
 			}
 		}
 	} else {
 		for _, result := range space {
 			if match, _, _ := p.MatchItem(result.item, false, slab); match != nil {
-				matches = append(matches, match)
+				matches = append(matches, *match)
 			}
 		}
 	}
@@ -286,14 +286,16 @@ func (p *Pattern) matchChunk(chunk *Chunk, space []*Result, slab *util.Slab) []*
 func (p *Pattern) MatchItem(item *Item, withPos bool, slab *util.Slab) (*Result, []Offset, *[]int) {
 	if p.extended {
 		if offsets, bonus, pos := p.extendedMatch(item, withPos, slab); len(offsets) == len(p.termSets) {
-			return buildResult(item, offsets, bonus), offsets, pos
+			result := buildResult(item, offsets, bonus)
+			return &result, offsets, pos
 		}
 		return nil, nil, nil
 	}
 	offset, bonus, pos := p.basicMatch(item, withPos, slab)
 	if sidx := offset[0]; sidx >= 0 {
 		offsets := []Offset{offset}
-		return buildResult(item, offsets, bonus), offsets, pos
+		result := buildResult(item, offsets, bonus)
+		return &result, offsets, pos
 	}
 	return nil, nil, nil
 }

src/result.go

@@ -19,22 +19,17 @@ type colorOffset struct {
 	index  int32
 }
 
-type rank struct {
-	points [4]uint16
-	index  int32
-}
-
 type Result struct {
-	item *Item
+	item   *Item
-	rank rank
+	points [4]uint16
 }
 
-func buildResult(item *Item, offsets []Offset, score int) *Result {
+func buildResult(item *Item, offsets []Offset, score int) Result {
 	if len(offsets) > 1 {
 		sort.Sort(ByOrder(offsets))
 	}
 
-	result := Result{item: item, rank: rank{index: item.Index()}}
+	result := Result{item: item}
 	numChars := item.text.Length()
 	minBegin := math.MaxUint16
 	minEnd := math.MaxUint16
@@ -75,10 +70,10 @@ func buildResult(item *Item, offsets []Offset, score int) *Result {
 				}
 			}
 		}
-		result.rank.points[idx] = val
+		result.points[idx] = val
 	}
 
-	return &result
+	return result
 }
 
 // Sort criteria to use. Never changes once fzf is started.
@@ -89,8 +84,8 @@ func (result *Result) Index() int32 {
 	return result.item.Index()
 }
 
-func minRank() rank {
+func minRank() Result {
-	return rank{index: 0, points: [4]uint16{math.MaxUint16, 0, 0, 0}}
+	return Result{item: &nilItem, points: [4]uint16{math.MaxUint16, 0, 0, 0}}
 }
 
 func (result *Result) colorOffsets(matchOffsets []Offset, theme *tui.ColorTheme, color tui.ColorPair, attr tui.Attr, current bool) []colorOffset {
@@ -201,7 +196,7 @@ func (a ByOrder) Less(i, j int) bool {
 }
 
 // ByRelevance is for sorting Items
-type ByRelevance []*Result
+type ByRelevance []Result
 
 func (a ByRelevance) Len() int {
 	return len(a)
@@ -212,11 +207,11 @@ func (a ByRelevance) Swap(i, j int) {
 }
 
 func (a ByRelevance) Less(i, j int) bool {
-	return compareRanks((*a[i]).rank, (*a[j]).rank, false)
+	return compareRanks(a[i], a[j], false)
 }
 
 // ByRelevanceTac is for sorting Items
-type ByRelevanceTac []*Result
+type ByRelevanceTac []Result
 
 func (a ByRelevanceTac) Len() int {
 	return len(a)
@@ -227,10 +222,10 @@ func (a ByRelevanceTac) Swap(i, j int) {
 }
 
 func (a ByRelevanceTac) Less(i, j int) bool {
-	return compareRanks((*a[i]).rank, (*a[j]).rank, true)
+	return compareRanks(a[i], a[j], true)
 }
 
-func compareRanks(irank rank, jrank rank, tac bool) bool {
+func compareRanks(irank Result, jrank Result, tac bool) bool {
 	for idx := 0; idx < 4; idx++ {
 		left := irank.points[idx]
 		right := jrank.points[idx]
@@ -240,5 +235,5 @@ func compareRanks(irank rank, jrank rank, tac bool) bool {
 			return false
 		}
 	}
-	return (irank.index <= jrank.index) != tac
+	return (irank.item.Index() <= jrank.item.Index()) != tac
 }

src/result_test.go

@@ -31,10 +31,10 @@ func TestOffsetSort(t *testing.T) {
 }
 
 func TestRankComparison(t *testing.T) {
-	rank := func(vals ...uint16) rank {
+	rank := func(vals ...uint16) Result {
-		return rank{
+		return Result{
 			points: [4]uint16{vals[0], vals[1], vals[2], vals[3]},
-			index:  int32(vals[4])}
+			item:   &Item{text: util.Chars{Index: int32(vals[4])}}}
 	}
 	if compareRanks(rank(3, 0, 0, 0, 5), rank(2, 0, 0, 0, 7), false) ||
 		!compareRanks(rank(3, 0, 0, 0, 5), rank(3, 0, 0, 0, 6), false) ||
@@ -59,23 +59,23 @@ func TestResultRank(t *testing.T) {
 	strs := [][]rune{[]rune("foo"), []rune("foobar"), []rune("bar"), []rune("baz")}
 	item1 := buildResult(
 		withIndex(&Item{text: util.RunesToChars(strs[0])}, 1), []Offset{}, 2)
-	if item1.rank.points[0] != math.MaxUint16-2 || // Bonus
+	if item1.points[0] != math.MaxUint16-2 || // Bonus
-		item1.rank.points[1] != 3 || // Length
+		item1.points[1] != 3 || // Length
-		item1.rank.points[2] != 0 || // Unused
+		item1.points[2] != 0 || // Unused
-		item1.rank.points[3] != 0 || // Unused
+		item1.points[3] != 0 || // Unused
 		item1.item.Index() != 1 {
-		t.Error(item1.rank)
+		t.Error(item1)
 	}
 	// Only differ in index
 	item2 := buildResult(&Item{text: util.RunesToChars(strs[0])}, []Offset{}, 2)
 
-	items := []*Result{item1, item2}
+	items := []Result{item1, item2}
 	sort.Sort(ByRelevance(items))
 	if items[0] != item2 || items[1] != item1 {
 		t.Error(items)
 	}
 
-	items = []*Result{item2, item1, item1, item2}
+	items = []Result{item2, item1, item1, item2}
 	sort.Sort(ByRelevance(items))
 	if items[0] != item2 || items[1] != item2 ||
 		items[2] != item1 || items[3] != item1 {
@@ -91,7 +91,7 @@ func TestResultRank(t *testing.T) {
 		withIndex(&Item{}, 2), []Offset{Offset{1, 3}, Offset{5, 7}}, 5)
 	item6 := buildResult(
 		withIndex(&Item{}, 2), []Offset{Offset{1, 2}, Offset{6, 7}}, 6)
-	items = []*Result{item1, item2, item3, item4, item5, item6}
+	items = []Result{item1, item2, item3, item4, item5, item6}
 	sort.Sort(ByRelevance(items))
 	if !(items[0] == item6 && items[1] == item5 &&
 		items[2] == item4 && items[3] == item3 &&

src/terminal.go

@@ -714,7 +714,7 @@ func (t *Terminal) printHeader() {
 			colors: colors}
 
 		t.move(line, 2, true)
-		t.printHighlighted(&Result{item: item},
+		t.printHighlighted(Result{item: item},
 			tui.AttrRegular, tui.ColHeader, tui.ColDefault, false, false)
 	}
 }
@@ -742,7 +742,7 @@ func (t *Terminal) printList() {
 	}
 }
 
-func (t *Terminal) printItem(result *Result, line int, i int, current bool) {
+func (t *Terminal) printItem(result Result, line int, i int, current bool) {
 	item := result.item
 	_, selected := t.selected[item.Index()]
 	label := " "
@@ -758,7 +758,7 @@ func (t *Terminal) printItem(result *Result, line int, i int, current bool) {
 
 	// Avoid unnecessary redraw
 	newLine := itemLine{current: current, selected: selected, label: label,
-		result: *result, queryLen: len(t.input), width: 0}
+		result: result, queryLen: len(t.input), width: 0}
 	prevLine := t.prevLines[i]
 	if prevLine.current == newLine.current &&
 		prevLine.selected == newLine.selected &&
@@ -840,7 +840,7 @@ func (t *Terminal) overflow(runes []rune, max int) bool {
 	return t.displayWidthWithLimit(runes, 0, max) > max
 }
 
-func (t *Terminal) printHighlighted(result *Result, attr tui.Attr, col1 tui.ColorPair, col2 tui.ColorPair, current bool, match bool) int {
+func (t *Terminal) printHighlighted(result Result, attr tui.Attr, col1 tui.ColorPair, col2 tui.ColorPair, current bool, match bool) int {
 	item := result.item
 
 	// Overflow