Optimization for buffer text

We no longer store a string representation of the buffer and instead
directly access it through the rope

cmd/micro/bindings.go

@@ -373,7 +373,7 @@ func (v *View) SelectDown() bool {
 // SelectLeft selects the character to the left of the cursor
 func (v *View) SelectLeft() bool {
 	loc := v.cursor.Loc()
-	count := Count(v.buf.text) - 1
+	count := v.buf.Len() - 1
 	if loc > count {
 		loc = count
 	}
@@ -388,7 +388,7 @@ func (v *View) SelectLeft() bool {
 // SelectRight selects the character to the right of the cursor
 func (v *View) SelectRight() bool {
 	loc := v.cursor.Loc()
-	count := Count(v.buf.text) - 1
+	count := v.buf.Len() - 1
 	if loc > count {
 		loc = count
 	}
@@ -465,7 +465,7 @@ func (v *View) CursorStart() bool {
 
 // CursorEnd moves the cursor to the end of the buffer
 func (v *View) CursorEnd() bool {
-	v.cursor.SetLoc(len(v.buf.text))
+	v.cursor.SetLoc(v.buf.Len())
 	return true
 }
 
@@ -487,7 +487,7 @@ func (v *View) SelectToEnd() bool {
 		v.cursor.origSelection[0] = loc
 	}
 	v.CursorEnd()
-	v.cursor.SelectTo(len(v.buf.text))
+	v.cursor.SelectTo(v.buf.Len())
 	return true
 }
 
@@ -570,7 +570,7 @@ func (v *View) Delete() bool {
 		v.cursor.ResetSelection()
 	} else {
 		loc := v.cursor.Loc()
-		if loc < len(v.buf.text) {
+		if loc < v.buf.Len() {
 			v.eh.Remove(loc, loc+1)
 		}
 	}

cmd/micro/buffer.go

@@ -27,7 +27,6 @@ type Buffer struct {
 	// Provide efficient and easy access to text and lines so the rope String does not
 	// need to be constantly recalculated
 	// These variables are updated in the update() function
-	text  string
 	lines []string
 
 	// Syntax highlighting rules
@@ -60,14 +59,17 @@ func (b *Buffer) UpdateRules() {
 	b.rules, b.filetype = GetRules(b)
 }
 
+func (b *Buffer) String() string {
+	text := ""
+	if b.r.Len() != 0 {
+		text = b.r.String()
+	}
+	return text
+}
+
 // Update fetches the string from the rope and updates the `text` and `lines` in the buffer
 func (b *Buffer) Update() {
-	if b.r.Len() == 0 {
-		b.text = ""
-	} else {
-		b.text = b.r.String()
-	}
-	b.lines = strings.Split(b.text, "\n")
+	b.lines = strings.Split(b.String(), "\n")
 }
 
 // Save saves the buffer to its default path
@@ -78,7 +80,7 @@ func (b *Buffer) Save() error {
 // SaveAs saves the buffer to a specified path (filename), creating the file if it does not exist
 func (b *Buffer) SaveAs(filename string) error {
 	b.UpdateRules()
-	data := []byte(b.text)
+	data := []byte(b.String())
 	err := ioutil.WriteFile(filename, data, 0644)
 	if err == nil {
 		b.savedText = md5.Sum(data)
@@ -93,17 +95,13 @@ func (b *Buffer) IsDirty() bool {
 		return false
 	}
 	if b.netInsertions == 0 {
-		isDirty := b.savedText != md5.Sum([]byte(b.text))
+		isDirty := b.savedText != md5.Sum([]byte(b.String()))
 		b.dirtySinceLastCheck = isDirty
 		return isDirty
 	}
 	return true
 }
 
-func (b *Buffer) Lines() []string {
-	return strings.Split(b.text, "\n")
-}
-
 // Insert a string into the rope
 func (b *Buffer) Insert(idx int, value string) {
 	b.dirtySinceLastCheck = true
@@ -123,7 +121,7 @@ func (b *Buffer) Remove(start, end int) string {
 	if end > b.Len() {
 		end = b.Len()
 	}
-	removed := b.text[start:end]
+	removed := b.r.Report(start+1, end-start)
 	// The rope implenentation I am using wants indicies starting at 1 instead of 0
 	start++
 	end++

cmd/micro/command.go

@@ -141,7 +141,7 @@ func HandleCommand(input string, view *View) {
 
 		found := false
 		for {
-			match := regex.FindStringIndex(view.buf.text)
+			match := regex.FindStringIndex(view.buf.String())
 			if match == nil {
 				break
 			}

cmd/micro/cursor.go

@@ -102,9 +102,9 @@ func (c *Cursor) DeleteSelection() {
 // GetSelection returns the cursor's selection
 func (c *Cursor) GetSelection() string {
 	if c.curSelection[0] > c.curSelection[1] {
-		return string([]rune(c.v.buf.text)[c.curSelection[1]:c.curSelection[0]])
+		return c.v.buf.r.Report(c.curSelection[1]+1, c.curSelection[0]-c.curSelection[1])
 	}
-	return string([]rune(c.v.buf.text)[c.curSelection[0]:c.curSelection[1]])
+	return c.v.buf.r.Report(c.curSelection[0]+1, c.curSelection[1]-c.curSelection[0])
 }
 
 // SelectLine selects the current line

cmd/micro/search.go

@@ -72,11 +72,12 @@ func Search(searchStr string, v *View, down bool) {
 	}
 	var str string
 	var charPos int
+	text := v.buf.String()
 	if down {
-		str = v.buf.text[searchStart:]
+		str = text[searchStart:]
 		charPos = searchStart
 	} else {
-		str = v.buf.text[:searchStart]
+		str = text[:searchStart]
 	}
 	r, err := regexp.Compile(searchStr)
 	if err != nil {
@@ -86,7 +87,7 @@ func Search(searchStr string, v *View, down bool) {
 	var match []int
 	if matches == nil {
 		// Search the entire buffer now
-		matches = r.FindAllStringIndex(v.buf.text, -1)
+		matches = r.FindAllStringIndex(text, -1)
 		charPos = 0
 		if matches == nil {
 			v.cursor.ResetSelection()