Micro-optimizations

- Make structs smaller
- Introduce Result struct and use it to represent matched items instead of
  reusing Item struct for that purpose
- Avoid unnecessary memory allocation
- Avoid growing slice from the initial capacity
- Code cleanup

19 files changed, 234 insertions, 568 deletions

diff --git a/src/algo/algo.go b/src/algo/algo.go
index 8825a059..00265c60 100644
--- a/src/algo/algo.go
+++ b/src/algo/algo.go
@@ -24,12 +24,12 @@ func indexAt(index int, max int, forward bool) int {
 
 // Result conatins the results of running a match function.
 type Result struct {
-	Start int32
-	End   int32
+	Start int
+	End   int
 
 	// Items are basically sorted by the lengths of matched substrings.
 	// But we slightly adjust the score with bonus for better results.
-	Bonus int32
+	Bonus int
 }
 
 type charClass int
@@ -42,8 +42,8 @@ const (
 	charNumber
 )
 
-func evaluateBonus(caseSensitive bool, text util.Chars, pattern []rune, sidx int, eidx int) int32 {
-	var bonus int32
+func evaluateBonus(caseSensitive bool, text util.Chars, pattern []rune, sidx int, eidx int) int {
+	var bonus int
 	pidx := 0
 	lenPattern := len(pattern)
 	consecutive := false
@@ -63,7 +63,7 @@ func evaluateBonus(caseSensitive bool, text util.Chars, pattern []rune, sidx int
 			class = charNonWord
 		}
 
-		var point int32
+		var point int
 		if prevClass == charNonWord && class != charNonWord {
 			// Word boundary
 			point = 2
@@ -181,7 +181,7 @@ func FuzzyMatch(caseSensitive bool, forward bool, text util.Chars, pattern []run
 			sidx, eidx = lenRunes-eidx, lenRunes-sidx
 		}
 
-		return Result{int32(sidx), int32(eidx),
+		return Result{sidx, eidx,
 			evaluateBonus(caseSensitive, text, pattern, sidx, eidx)}
 	}
 	return Result{-1, -1, 0}
@@ -228,7 +228,7 @@ func ExactMatchNaive(caseSensitive bool, forward bool, text util.Chars, pattern
 					sidx = lenRunes - (index + 1)
 					eidx = lenRunes - (index - lenPattern + 1)
 				}
-				return Result{int32(sidx), int32(eidx),
+				return Result{sidx, eidx,
 					evaluateBonus(caseSensitive, text, pattern, sidx, eidx)}
 			}
 		} else {
@@ -255,7 +255,7 @@ func PrefixMatch(caseSensitive bool, forward bool, text util.Chars, pattern []ru
 		}
 	}
 	lenPattern := len(pattern)
-	return Result{0, int32(lenPattern),
+	return Result{0, lenPattern,
 		evaluateBonus(caseSensitive, text, pattern, 0, lenPattern)}
 }
 
@@ -279,7 +279,7 @@ func SuffixMatch(caseSensitive bool, forward bool, text util.Chars, pattern []ru
 	lenPattern := len(pattern)
 	sidx := trimmedLen - lenPattern
 	eidx := trimmedLen
-	return Result{int32(sidx), int32(eidx),
+	return Result{sidx, eidx,
 		evaluateBonus(caseSensitive, text, pattern, sidx, eidx)}
 }
 
@@ -294,7 +294,7 @@ func EqualMatch(caseSensitive bool, forward bool, text util.Chars, pattern []run
 		runesStr = strings.ToLower(runesStr)
 	}
 	if runesStr == string(pattern) {
-		return Result{0, int32(len(pattern)), 0}
+		return Result{0, len(pattern), 0}
 	}
 	return Result{-1, -1, 0}
 }
diff --git a/src/algo/algo_test.go b/src/algo/algo_test.go
index d6a5d487..7034dcef 100644
--- a/src/algo/algo_test.go
+++ b/src/algo/algo_test.go
@@ -7,7 +7,7 @@ import (
 	"github.com/junegunn/fzf/src/util"
 )
 
-func assertMatch(t *testing.T, fun func(bool, bool, util.Chars, []rune) Result, caseSensitive, forward bool, input, pattern string, sidx int32, eidx int32, bonus int32) {
+func assertMatch(t *testing.T, fun func(bool, bool, util.Chars, []rune) Result, caseSensitive, forward bool, input, pattern string, sidx int, eidx int, bonus int) {
 	if !caseSensitive {
 		pattern = strings.ToLower(pattern)
 	}
diff --git a/src/ansi.go b/src/ansi.go
index 56831eee..0a525671 100644
--- a/src/ansi.go
+++ b/src/ansi.go
@@ -36,7 +36,7 @@ func init() {
 	ansiRegex = regexp.MustCompile("\x1b\\[[0-9;]*[mK]")
 }
 
-func extractColor(str string, state *ansiState, proc func(string, *ansiState) bool) (string, []ansiOffset, *ansiState) {
+func extractColor(str string, state *ansiState, proc func(string, *ansiState) bool) (string, *[]ansiOffset, *ansiState) {
 	var offsets []ansiOffset
 	var output bytes.Buffer
 
@@ -84,7 +84,10 @@ func extractColor(str string, state *ansiState, proc func(string, *ansiState) bo
 	if proc != nil {
 		proc(rest, state)
 	}
-	return output.String(), offsets, state
+	if len(offsets) == 0 {
+		return output.String(), nil, state
+	}
+	return output.String(), &offsets, state
 }
 
 func interpretCode(ansiCode string, prevState *ansiState) *ansiState {
diff --git a/src/ansi_test.go b/src/ansi_test.go
index 31803f38..a80e98ad 100644
--- a/src/ansi_test.go
+++ b/src/ansi_test.go
@@ -16,7 +16,7 @@ func TestExtractColor(t *testing.T) {
 	src := "hello world"
 	var state *ansiState
 	clean := "\x1b[0m"
-	check := func(assertion func(ansiOffsets []ansiOffset, state *ansiState)) {
+	check := func(assertion func(ansiOffsets *[]ansiOffset, state *ansiState)) {
 		output, ansiOffsets, newState := extractColor(src, state, nil)
 		state = newState
 		if output != "hello world" {
@@ -26,127 +26,127 @@ func TestExtractColor(t *testing.T) {
 		assertion(ansiOffsets, state)
 	}
 
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) > 0 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if offsets != nil {
 			t.Fail()
 		}
 	})
 
 	state = nil
 	src = "\x1b[0mhello world"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) > 0 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if offsets != nil {
 			t.Fail()
 		}
 	})
 
 	state = nil
 	src = "\x1b[1mhello world"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 1 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 1 {
 			t.Fail()
 		}
-		assert(offsets[0], 0, 11, -1, -1, true)
+		assert((*offsets)[0], 0, 11, -1, -1, true)
 	})
 
 	state = nil
 	src = "\x1b[1mhello \x1b[mworld"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 1 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 1 {
 			t.Fail()
 		}
-		assert(offsets[0], 0, 6, -1, -1, true)
+		assert((*offsets)[0], 0, 6, -1, -1, true)
 	})
 
 	state = nil
 	src = "\x1b[1mhello \x1b[Kworld"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 1 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 1 {
 			t.Fail()
 		}
-		assert(offsets[0], 0, 11, -1, -1, true)
+		assert((*offsets)[0], 0, 11, -1, -1, true)
 	})
 
 	state = nil
 	src = "hello \x1b[34;45;1mworld"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 1 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 1 {
 			t.Fail()
 		}
-		assert(offsets[0], 6, 11, 4, 5, true)
+		assert((*offsets)[0], 6, 11, 4, 5, true)
 	})
 
 	state = nil
 	src = "hello \x1b[34;45;1mwor\x1b[34;45;1mld"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 1 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 1 {
 			t.Fail()
 		}
-		assert(offsets[0], 6, 11, 4, 5, true)
+		assert((*offsets)[0], 6, 11, 4, 5, true)
 	})
 
 	state = nil
 	src = "hello \x1b[34;45;1mwor\x1b[0mld"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 1 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 1 {
 			t.Fail()
 		}
-		assert(offsets[0], 6, 9, 4, 5, true)
+		assert((*offsets)[0], 6, 9, 4, 5, true)
 	})
 
 	state = nil
 	src = "hello \x1b[34;48;5;233;1mwo\x1b[38;5;161mr\x1b[0ml\x1b[38;5;161md"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 3 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 3 {
 			t.Fail()
 		}
-		assert(offsets[0], 6, 8, 4, 233, true)
-		assert(offsets[1], 8, 9, 161, 233, true)
-		assert(offsets[2], 10, 11, 161, -1, false)
+		assert((*offsets)[0], 6, 8, 4, 233, true)
+		assert((*offsets)[1], 8, 9, 161, 233, true)
+		assert((*offsets)[2], 10, 11, 161, -1, false)
 	})
 
 	// {38,48};5;{38,48}
 	state = nil
 	src = "hello \x1b[38;5;38;48;5;48;1mwor\x1b[38;5;48;48;5;38ml\x1b[0md"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 2 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 2 {
 			t.Fail()
 		}
-		assert(offsets[0], 6, 9, 38, 48, true)
-		assert(offsets[1], 9, 10, 48, 38, true)
+		assert((*offsets)[0], 6, 9, 38, 48, true)
+		assert((*offsets)[1], 9, 10, 48, 38, true)
 	})
 
 	src = "hello \x1b[32;1mworld"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 1 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 1 {
 			t.Fail()
 		}
 		if state.fg != 2 || state.bg != -1 || !state.bold {
 			t.Fail()
 		}
-		assert(offsets[0], 6, 11, 2, -1, true)
+		assert((*offsets)[0], 6, 11, 2, -1, true)
 	})
 
 	src = "hello world"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 1 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 1 {
 			t.Fail()
 		}
 		if state.fg != 2 || state.bg != -1 || !state.bold {
 			t.Fail()
 		}
-		assert(offsets[0], 0, 11, 2, -1, true)
+		assert((*offsets)[0], 0, 11, 2, -1, true)
 	})
 
 	src = "hello \x1b[0;38;5;200;48;5;100mworld"
-	check(func(offsets []ansiOffset, state *ansiState) {
-		if len(offsets) != 2 {
+	check(func(offsets *[]ansiOffset, state *ansiState) {
+		if len(*offsets) != 2 {
 			t.Fail()
 		}
 		if state.fg != 200 || state.bg != 100 || state.bold {
 			t.Fail()
 		}
-		assert(offsets[0], 0, 6, 2, -1, true)
-		assert(offsets[1], 6, 11, 200, 100, false)
+		assert((*offsets)[0], 0, 6, 2, -1, true)
+		assert((*offsets)[1], 6, 11, 200, 100, false)
 	})
 }
diff --git a/src/cache.go b/src/cache.go
index d2ec00b4..baf88dd8 100644
--- a/src/cache.go
+++ b/src/cache.go
@@ -3,7 +3,7 @@ package fzf
 import "sync"
 
 // queryCache associates strings to lists of items
-type queryCache map[string][]*Item
+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 []*Item) {
+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 []*Item) {
 }
 
 // Find is called to lookup ChunkCache
-func (cc *ChunkCache) Find(chunk *Chunk, key string) ([]*Item, bool) {
+func (cc *ChunkCache) Find(chunk *Chunk, key string) ([]*Result, bool) {
 	if len(key) == 0 || !chunk.IsFull() {
 		return nil, false
 	}
diff --git a/src/cache_test.go b/src/cache_test.go
index 05f904c9..8703fc41 100644
--- a/src/cache_test.go
+++ b/src/cache_test.go
@@ -7,8 +7,8 @@ func TestChunkCache(t *testing.T) {
 	chunk2 := make(Chunk, chunkSize)
 	chunk1p := &Chunk{}
 	chunk2p := &chunk2
-	items1 := []*Item{&Item{}}
-	items2 := []*Item{&Item{}, &Item{}}
+	items1 := []*Result{&Result{}}
+	items2 := []*Result{&Result{}, &Result{}}
 	cache.Add(chunk1p, "foo", items1)
 	cache.Add(chunk2p, "foo", items1)
 	cache.Add(chunk2p, "bar", items2)
diff --git a/src/chunklist_test.go b/src/chunklist_test.go
index 2523675a..594daebb 100644
--- a/src/chunklist_test.go
+++ b/src/chunklist_test.go
@@ -12,7 +12,7 @@ func TestChunkList(t *testing.T) {
 	sortCriteria = []criterion{byMatchLen, byLength}
 
 	cl := NewChunkList(func(s []byte, i int) *Item {
-		return &Item{text: util.ToChars(s), rank: buildEmptyRank(int32(i * 2))}
+		return &Item{text: util.ToChars(s), index: int32(i * 2)}
 	})
 
 	// Snapshot
@@ -41,11 +41,8 @@ func TestChunkList(t *testing.T) {
 	if len(*chunk1) != 2 {
 		t.Error("Snapshot should contain only two items")
 	}
-	last := func(arr [5]int32) int32 {
-		return arr[len(arr)-1]
-	}
-	if (*chunk1)[0].text.ToString() != "hello" || last((*chunk1)[0].rank) != 0 ||
-		(*chunk1)[1].text.ToString() != "world" || last((*chunk1)[1].rank) != 2 {
+	if (*chunk1)[0].text.ToString() != "hello" || (*chunk1)[0].index != 0 ||
+		(*chunk1)[1].text.ToString() != "world" || (*chunk1)[1].index != 2 {
 		t.Error("Invalid data")
 	}
 	if chunk1.IsFull() {
diff --git a/src/core.go b/src/core.go
index 76d30d1a..290c0af0 100644
--- a/src/core.go
+++ b/src/core.go
@@ -56,16 +56,16 @@ func Run(opts *Options) {
 	eventBox := util.NewEventBox()
 
 	// ANSI code processor
-	ansiProcessor := func(data []byte) (util.Chars, []ansiOffset) {
+	ansiProcessor := func(data []byte) (util.Chars, *[]ansiOffset) {
 		return util.ToChars(data), nil
 	}
-	ansiProcessorRunes := func(data []rune) (util.Chars, []ansiOffset) {
+	ansiProcessorRunes := func(data []rune) (util.Chars, *[]ansiOffset) {
 		return util.RunesToChars(data), nil
 	}
 	if opts.Ansi {
 		if opts.Theme != nil {
 			var state *ansiState
-			ansiProcessor = func(data []byte) (util.Chars, []ansiOffset) {
+			ansiProcessor = func(data []byte) (util.Chars, *[]ansiOffset) {
 				trimmed, offsets, newState := extractColor(string(data), state, nil)
 				state = newState
 				return util.RunesToChars([]rune(trimmed)), offsets
@@ -73,12 +73,12 @@ func Run(opts *Options) {
 		} else {
 			// When color is disabled but ansi option is given,
 			// we simply strip out ANSI codes from the input
-			ansiProcessor = func(data []byte) (util.Chars, []ansiOffset) {
+			ansiProcessor = func(data []byte) (util.Chars, *[]ansiOffset) {
 				trimmed, _, _ := extractColor(string(data), nil, nil)
 				return util.RunesToChars([]rune(trimmed)), nil
 			}
 		}
-		ansiProcessorRunes = func(data []rune) (util.Chars, []ansiOffset) {
+		ansiProcessorRunes = func(data []rune) (util.Chars, *[]ansiOffset) {
 			return ansiProcessor([]byte(string(data)))
 		}
 	}
@@ -95,14 +95,13 @@ func Run(opts *Options) {
 			}
 			chars, colors := ansiProcessor(data)
 			return &Item{
+				index:  int32(index),
 				text:   chars,
-				colors: colors,
-				rank:   buildEmptyRank(int32(index))}
+				colors: colors}
 		})
 	} else {
 		chunkList = NewChunkList(func(data []byte, index int) *Item {
-			chars := util.ToChars(data)
-			tokens := Tokenize(chars, opts.Delimiter)
+			tokens := Tokenize(util.ToChars(data), opts.Delimiter)
 			trans := Transform(tokens, opts.WithNth)
 			if len(header) < opts.HeaderLines {
 				header = append(header, string(joinTokens(trans)))
@@ -111,10 +110,9 @@ func Run(opts *Options) {
 			}
 			textRunes := joinTokens(trans)
 			item := Item{
-				text:     util.RunesToChars(textRunes),
+				index:    int32(index),
 				origText: &data,
-				colors:   nil,
-				rank:     buildEmptyRank(int32(index))}
+				colors:   nil}
 
 			trimmed, colors := ansiProcessorRunes(textRunes)
 			item.text = trimmed
@@ -163,7 +161,7 @@ func Run(opts *Options) {
 			reader := Reader{
 				func(runes []byte) bool {
 					item := chunkList.trans(runes, 0)
-					if item != nil && pattern.MatchItem(item) {
+					if item != nil && pattern.MatchItem(item) != nil {
 						fmt.Println(item.text.ToString())
 						found = true
 					}
@@ -179,7 +177,7 @@ func Run(opts *Options) {
 				chunks:  snapshot,
 				pattern: pattern})
 			for i := 0; i < merger.Length(); i++ {
-				fmt.Println(merger.Get(i).AsString(opts.Ansi))
+				fmt.Println(merger.Get(i).item.AsString(opts.Ansi))
 				found = true
 			}
 		}
@@ -259,7 +257,7 @@ func Run(opts *Options) {
 										fmt.Println()
 									}
 									for i := 0; i < count; i++ {
-										fmt.Println(val.Get(i).AsString(opts.Ansi))
+										fmt.Println(val.Get(i).item.AsString(opts.Ansi))
 									}
 									if count > 0 {
 										os.Exit(exitOk)
diff --git a/src/item.go b/src/item.go
index 584dfd85..4e60fafb 100644
--- a/src/item.go
+++ b/src/item.go
@@ -1,295 +1,39 @@
 package fzf
 
 import (
-	"math"
-
-	"github.com/junegunn/fzf/src/curses"
 	"github.com/junegunn/fzf/src/util"
 )
 
-// Offset holds three 32-bit integers denoting the offsets of a matched substring
-type Offset [3]int32
-
-type colorOffset struct {
-	offset [2]int32
-	color  int
-	bold   bool
-}
-
 // Item represents each input line
 type Item struct {
+	index       int32
 	text        util.Chars
 	origText    *[]byte
+	colors      *[]ansiOffset
 	transformed []Token
-	offsets     []Offset
-	colors      []ansiOffset
-	rank        [5]int32
-	bonus       int32
-}
-
-// Sort criteria to use. Never changes once fzf is started.
-var sortCriteria []criterion
-
-func isRankValid(rank [5]int32) bool {
-	// Exclude ordinal index
-	for _, r := range rank[:4] {
-		if r > 0 {
-			return true
-		}
-	}
-	return false
-}
-
-func buildEmptyRank(index int32) [5]int32 {
-	return [5]int32{0, 0, 0, 0, index}
 }
 
 // Index returns ordinal index of the Item
 func (item *Item) Index() int32 {
-	return item.rank[4]
+	return item.index
 }
 
-// Rank calculates rank of the Item
-func (item *Item) Rank(cache bool) [5]int32 {
-	if cache && isRankValid(item.rank) {
-		return item.rank
-	}
-	matchlen := 0
-	prevEnd := 0
-	lenSum := 0
-	minBegin := math.MaxInt32
-	for _, offset := range item.offsets {
-		begin := int(offset[0])
-		end := int(offset[1])
-		trimLen := int(offset[2])
-		lenSum += trimLen
-		if prevEnd > begin {
-			begin = prevEnd
-		}
-		if end > prevEnd {
-			prevEnd = end
-		}
-		if end > begin {
-			if begin < minBegin {
-				minBegin = begin
-			}
-			matchlen += end - begin
-		}
-	}
-	rank := buildEmptyRank(item.Index())
-	for idx, criterion := range sortCriteria {
-		var val int32
-		switch criterion {
-		case byMatchLen:
-			if matchlen == 0 {
-				val = math.MaxInt32
-			} else {
-				// It is extremely unlikely that bonus exceeds 128
-				val = 128*int32(matchlen) - item.bonus
-			}
-		case byLength:
-			// It is guaranteed that .transformed in not null in normal execution
-			if item.transformed != nil {
-				// If offsets is empty, lenSum will be 0, but we don't care
-				val = int32(lenSum)
-			} else {
-				val = int32(item.text.Length())
-			}
-		case byBegin:
-			// We can't just look at item.offsets[0][0] because it can be an inverse term
-			whitePrefixLen := 0
-			numChars := item.text.Length()
-			for idx := 0; idx < numChars; idx++ {
-				r := item.text.Get(idx)
-				whitePrefixLen = idx
-				if idx == minBegin || r != ' ' && r != '\t' {
-					break
-				}
-			}
-			val = int32(minBegin - whitePrefixLen)
-		case byEnd:
-			if prevEnd > 0 {
-				val = int32(1 + item.text.Length() - prevEnd)
-			} else {
-				// Empty offsets due to inverse terms.
-				val = 1
-			}
-		}
-		rank[idx] = val
-	}
-	if cache {
-		item.rank = rank
+// Colors returns ansiOffsets of the Item
+func (item *Item) Colors() []ansiOffset {
+	if item.colors == nil {
+		return []ansiOffset{}
 	}
-	return rank
+	return *item.colors
 }
 
 // AsString returns the original string
 func (item *Item) AsString(stripAnsi bool) string {
-	return *item.StringPtr(stripAnsi)
-}
-
-// StringPtr returns the pointer to the original string
-func (item *Item) StringPtr(stripAnsi bool) *string {
 	if item.origText != nil {
 		if stripAnsi {
 			trimmed, _, _ := extractColor(string(*item.origText), nil, nil)
-			return &trimmed
-		}
-		orig := string(*item.origText)
-		return &orig
-	}
-	str := item.text.ToString()
-	return &str
-}
-
-func (item *Item) colorOffsets(color int, bold bool, current bool) []colorOffset {
-	if len(item.colors) == 0 {
-		var offsets []colorOffset
-		for _, off := range item.offsets {
-
-			offsets = append(offsets, colorOffset{offset: [2]int32{off[0], off[1]}, color: color, bold: bold})
-		}
-		return offsets
-	}
-
-	// Find max column
-	var maxCol int32
-	for _, off := range item.offsets {
-		if off[1] > maxCol {
-			maxCol = off[1]
-		}
-	}
-	for _, ansi := range item.colors {
-		if ansi.offset[1] > maxCol {
-			maxCol = ansi.offset[1]
-		}
-	}
-	cols := make([]int, maxCol)
-
-	for colorIndex, ansi := range item.colors {
-		for i := ansi.offset[0]; i < ansi.offset[1]; i++ {
-			cols[i] = colorIndex + 1 // XXX
-		}
-	}
-
-	for _, off := range item.offsets {
-		for i := off[0]; i < off[1]; i++ {
-			cols[i] = -1
-		}
-	}
-
-	// sort.Sort(ByOrder(offsets))
-
-	// Merge offsets
-	// ------------  ----  --  ----
-	//   ++++++++      ++++++++++
-	// --++++++++--  --++++++++++---
-	curr := 0
-	start := 0
-	var offsets []colorOffset
-	add := func(idx int) {
-		if curr != 0 && idx > start {
-			if curr == -1 {
-				offsets = append(offsets, colorOffset{
-					offset: [2]int32{int32(start), int32(idx)}, color: color, bold: bold})
-			} else {
-				ansi := item.colors[curr-1]
-				fg := ansi.color.fg
-				if fg == -1 {
-					if current {
-						fg = curses.CurrentFG
-					} else {
-						fg = curses.FG
-					}
-				}
-				bg := ansi.color.bg
-				if bg == -1 {
-					if current {
-						bg = curses.DarkBG
-					} else {
-						bg = curses.BG
-					}
-				}
-				offsets = append(offsets, colorOffset{
-					offset: [2]int32{int32(start), int32(idx)},
-					color:  curses.PairFor(fg, bg),
-					bold:   ansi.color.bold || bold})
-			}
-		}
-	}
-	for idx, col := range cols {
-		if col != curr {
-			add(idx)
-			start = idx
-			curr = col
-		}
-	}
-	add(int(maxCol))
-	return offsets
-}
-
-// ByOrder is for sorting substring offsets
-type ByOrder []Offset
-
-func (a ByOrder) Len() int {
-	return len(a)
-}
-
-func (a ByOrder) Swap(i, j int) {
-	a[i], a[j] = a[j], a[i]
-}
-
-func (a ByOrder) Less(i, j int) bool {
-	ioff := a[i]
-	joff := a[j]
-	return (ioff[0] < joff[0]) || (ioff[0] == joff[0]) && (ioff[1] <= joff[1])
-}
-
-// ByRelevance is for sorting Items
-type ByRelevance []*Item
-
-func (a ByRelevance) Len() int {
-	return len(a)
-}
-
-func (a ByRelevance) Swap(i, j int) {
-	a[i], a[j] = a[j], a[i]
-}
-
-func (a ByRelevance) Less(i, j int) bool {
-	irank := a[i].Rank(true)
-	jrank := a[j].Rank(true)
-
-	return compareRanks(irank, jrank, false)
-}
-
-// ByRelevanceTac is for sorting Items
-type ByRelevanceTac []*Item
-
-func (a ByRelevanceTac) Len() int {
-	return len(a)
-}
-
-func (a ByRelevanceTac) Swap(i, j int) {
-	a[i], a[j] = a[j], a[i]
-}
-
-func (a ByRelevanceTac) Less(i, j int) bool {
-	irank := a[i].Rank(true)
-	jrank := a[j].Rank(true)
-
-	return compareRanks(irank, jrank, true)
-}
-
-func compareRanks(irank [5]int32, jrank [5]int32, tac bool) bool {
-	for idx := 0; idx < 4; idx++ {
-		left := irank[idx]
-		right := jrank[idx]
-		if left < right {
-			return true
-		} else if left > right {
-			return false
+			return trimmed
 		}
+		return string(*item.origText)
 	}
-	return (irank[4] <= jrank[4]) != tac
+	return item.text.ToString()
 }
diff --git a/src/item_test.go b/src/item_test.go
index 36a436d3..1efb5f1d 100644
--- a/src/item_test.go
+++ b/src/item_test.go
@@ -1,109 +1,23 @@
 package fzf
 
 import (
-	"math"
-	"sort"
 	"testing"
 
-	"github.com/junegunn/fzf/src/curses"
 	"github.com/junegunn/fzf/src/util"
 )
 
-func TestOffsetSort(t *testing.T) {
-	offsets := []Offset{
-		Offset{3, 5}, Offset{2, 7},
-		Offset{1, 3}, Offset{2, 9}}
-	sort.Sort(ByOrder(offsets))
-
-	if offsets[0][0] != 1 || offsets[0][1] != 3 ||
-		offsets[1][0] != 2 || offsets[1][1] != 7 ||
-		offsets[2][0] != 2 || offsets[2][1] != 9 ||
-		offsets[3][0] != 3 || offsets[3][1] != 5 {
-		t.Error("Invalid order:", offsets)
-	}
-}
-
-func TestRankComparison(t *testing.T) {
-	if compareRanks([5]int32{3, 0, 0, 0, 5}, [5]int32{2, 0, 0, 0, 7}, false) ||
-		!compareRanks([5]int32{3, 0, 0, 0, 5}, [5]int32{3, 0, 0, 0, 6}, false) ||
-		!compareRanks([5]int32{1, 2, 0, 0, 3}, [5]int32{1, 3, 0, 0, 2}, false) ||
-		!compareRanks([5]int32{0, 0, 0, 0, 0}, [5]int32{0, 0, 0, 0, 0}, false) {
-		t.Error("Invalid order")
-	}
-
-	if compareRanks([5]int32{3, 0, 0, 0, 5}, [5]int32{2, 0, 0, 0, 7}, true) ||
-		!compareRanks([5]int32{3, 0, 0, 0, 5}, [5]int32{3, 0, 0, 0, 6}, false) ||
-		!compareRanks([5]int32{1, 2, 0, 0, 3}, [5]int32{1, 3, 0, 0, 2}, true) ||
-		!compareRanks([5]int32{0, 0, 0, 0, 0}, [5]int32{0, 0, 0, 0, 0}, false) {
-		t.Error("Invalid order (tac)")
-	}
-}
-
-// Match length, string length, index
-func TestItemRank(t *testing.T) {
-	// FIXME global
-	sortCriteria = []criterion{byMatchLen, byLength}
-
-	strs := [][]rune{[]rune("foo"), []rune("foobar"), []rune("bar"), []rune("baz")}
-	item1 := Item{text: util.RunesToChars(strs[0]), offsets: []Offset{}, rank: [5]int32{0, 0, 0, 0, 1}}
-	rank1 := item1.Rank(true)
-	if rank1[0] != math.MaxInt32 || rank1[1] != 3 || rank1[4] != 1 {
-		t.Error(item1.Rank(true))
+func TestStringPtr(t *testing.T) {
+	orig := []byte("\x1b[34mfoo")
+	text := []byte("\x1b[34mbar")
+	item := Item{origText: &orig, text: util.ToChars(text)}
+	if item.AsString(true) != "foo" || item.AsString(false) != string(orig) {
+		t.Fail()
 	}
-	// Only differ in index
-	item2 := Item{text: util.RunesToChars(strs[0]), offsets: []Offset{}}
-
-	items := []*Item{&item1, &item2}
-	sort.Sort(ByRelevance(items))
-	if items[0] != &item2 || items[1] != &item1 {
-		t.Error(items)
+	if item.AsString(true) != "foo" {
+		t.Fail()
 	}
-
-	items = []*Item{&item2, &item1, &item1, &item2}
-	sort.Sort(ByRelevance(items))
-	if items[0] != &item2 || items[1] != &item2 ||
-		items[2] != &item1 || items[3] != &item1 {
-		t.Error(items)
-	}
-
-	// Sort by relevance
-	item3 := Item{text: util.RunesToChars(strs[1]), rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 3}, Offset{5, 7}}}
-	item4 := Item{text: util.RunesToChars(strs[1]), rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 2}, Offset{6, 7}}}
-	item5 := Item{text: util.RunesToChars(strs[2]), rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 3}, Offset{5, 7}}}
-	item6 := Item{text: util.RunesToChars(strs[2]), rank: [5]int32{0, 0, 0, 0, 2}, offsets: []Offset{Offset{1, 2}, Offset{6, 7}}}
-	items = []*Item{&item1, &item2, &item3, &item4, &item5, &item6}
-	sort.Sort(ByRelevance(items))
-	if items[0] != &item6 || items[1] != &item4 ||
-		items[2] != &item5 || items[3] != &item3 ||
-		items[4] != &item2 || items[5] != &item1 {
-		t.Error(items)
-	}
-}
-
-func TestColorOffset(t *testing.T) {
-	// ------------ 20 ----  --  ----
-	//   ++++++++        ++++++++++
-	// --++++++++--    --++++++++++---
-	item := Item{
-		offsets: []Offset{Offset{5, 15}, Offset{25, 35}},
-		colors: []ansiOffset{
-			ansiOffset{[2]int32{0, 20}, ansiState{1, 5, false}},
-			ansiOffset{[2]int32{22, 27}, ansiState{2, 6, true}},
-			ansiOffset{[2]int32{30, 32}, ansiState{3, 7, false}},
-			ansiOffset{[2]int32{33, 40}, ansiState{4, 8, true}}}}
-	// [{[0 5] 9 false} {[5 15] 99 false} {[15 20] 9 false} {[22 25] 10 true} {[25 35] 99 false} {[35 40] 11 true}]
-
-	offsets := item.colorOffsets(99, false, true)
-	assert := func(idx int, b int32, e int32, c int, bold bool) {
-		o := offsets[idx]
-		if o.offset[0] != b || o.offset[1] != e || o.color != c || o.bold != bold {
-			t.Error(o)
-		}
+	item.origText = nil
+	if item.AsString(true) != string(text) || item.AsString(false) != string(text) {
+		t.Fail()
 	}
-	assert(0, 0, 5, curses.ColUser, false)
-	assert(1, 5, 15, 99, false)
-	assert(2, 15, 20, curses.ColUser, false)
-	assert(3, 22, 25, curses.ColUser+1, true)
-	assert(4, 25, 35, 99, false)
-	assert(5, 35, 40, curses.ColUser+2, true)
 }
diff --git a/src/matcher.go b/src/matcher.go
index 4c00db7e..8cd9a9f8 100644
--- a/src/matcher.go
+++ b/src/matcher.go
@@ -128,7 +128,7 @@ func (m *Matcher) sliceChunks(chunks []*Chunk) [][]*Chunk {
 
 type partialResult struct {
 	index   int
-	matches []*Item
+	matches []*Result
 }
 
 func (m *Matcher) scan(request MatchRequest) (*Merger, bool) {
@@ -155,15 +155,21 @@ func (m *Matcher) scan(request MatchRequest) (*Merger, bool) {
 		waitGroup.Add(1)
 		go func(idx int, chunks []*Chunk) {
 			defer func() { waitGroup.Done() }()
-			sliceMatches := []*Item{}
-			for _, chunk := range chunks {
+			count := 0
+			allMatches := make([][]*Result, len(chunks))
+			for idx, chunk := range chunks {
 				matches := request.pattern.Match(chunk)
-				sliceMatches = append(sliceMatches, matches...)
+				allMatches[idx] = matches
+				count += len(matches)
 				if cancelled.Get() {
 					return
 				}
 				countChan <- len(matches)
 			}
+			sliceMatches := make([]*Result, 0, count)
+			for _, matches := range allMatches {
+				sliceMatches = append(sliceMatches, matches...)
+			}
 			if m.sort {
 				if m.tac {
 					sort.Sort(ByRelevanceTac(sliceMatches))
@@ -200,7 +206,7 @@ func (m *Matcher) scan(request MatchRequest) (*Merger, bool) {
 		}
 	}
 
-	partialResults := make([][]*Item, numSlices)
+	partialResults := make([][]*Result, numSlices)
 	for _ = range slices {
 		partialResult := <-resultChan
 		partialResults[partialResult.index] = partialResult.matches
diff --git a/src/merger.go b/src/merger.go
index 0d3fb801..3879ab7e 100644
--- a/src/merger.go
+++ b/src/merger.go
@@ -3,13 +3,13 @@ package fzf
 import "fmt"
 
 // EmptyMerger is a Merger with no data
-var EmptyMerger = NewMerger([][]*Item{}, false, false)
+var EmptyMerger = NewMerger([][]*Result{}, false, false)
 
 // Merger holds a set of locally sorted lists of items and provides the view of