Syntax highlighting optimizations

src/cursor.go

@@ -6,12 +6,19 @@ import (
 
 // FromCharPos converts from a character position to an x, y position
 func FromCharPos(loc int, buf *Buffer) (int, int) {
-	charNum := 0
-	x, y := 0, 0
+	return FromCharPosStart(0, 0, 0, loc, buf)
+}
 
-	for charNum+Count(buf.lines[y])+1 <= loc {
-		charNum += Count(buf.lines[y]) + 1
+// FromCharPosStart converts from a character position to an x, y position, starting at the specified character location
+func FromCharPosStart(startLoc, startX, startY, loc int, buf *Buffer) (int, int) {
+	charNum := startLoc
+	x, y := startX, startY
+
+	lineLen := Count(buf.lines[y]) + 1
+	for charNum+lineLen <= loc {
+		charNum += lineLen
 		y++
+		lineLen = Count(buf.lines[y]) + 1
 	}
 	x = loc - charNum
 

src/highlighter.go

@@ -296,15 +296,20 @@ func Match(v *View) SyntaxMatches {
 	str := strings.Join(buf.lines[totalStart:totalEnd], "\n")
 	startNum := ToCharPos(0, totalStart, v.buf)
 
+	toplineNum := ToCharPos(0, v.topline, v.buf)
+	bottomlineNum := ToCharPos(0, v.topline+v.height, v.buf)
+
 	for _, rule := range rules {
 		if rule.startend {
-			if rule.regex.MatchString(str) {
-				indicies := rule.regex.FindAllStringIndex(str, -1)
+			if indicies := rule.regex.FindAllStringIndex(str, -1); indicies != nil {
 				for _, value := range indicies {
 					value[0] += startNum
 					value[1] += startNum
 					for i := value[0]; i < value[1]; i++ {
-						colNum, lineNum := FromCharPos(i, buf)
+						if i < toplineNum || i > bottomlineNum {
+							continue
+						}
+						colNum, lineNum := FromCharPosStart(toplineNum, 0, v.topline, i, buf)
 						if lineNum == -1 || colNum == -1 {
 							continue
 						}
@@ -317,8 +322,7 @@ func Match(v *View) SyntaxMatches {
 			}
 		} else {
 			for lineN, line := range lines {
-				if rule.regex.MatchString(line) {
-					indicies := rule.regex.FindAllStringIndex(line, -1)
+				if indicies := rule.regex.FindAllStringIndex(line, -1); indicies != nil {
 					for _, value := range indicies {
 						for i := value[0]; i < value[1]; i++ {
 							// matches[lineN+updateStart][i] = rule.style

src/micro.go

@@ -22,6 +22,8 @@ var screen tcell.Screen
 // Object to send messages and prompts to the user
 var messenger *Messenger
 
+var redrawStatus int
+
 // LoadInput loads the file input for the editor
 func LoadInput() (string, []byte, error) {
 	// There are a number of ways micro should start given its input

src/view.go

@@ -257,10 +257,7 @@ func (v *View) Paste() {
 		}
 		clip, _ := clipboard.ReadAll()
 		v.eh.Insert(v.cursor.Loc(), clip)
-		// This is a bit weird... Not sure if there's a better way
-		for i := 0; i < Count(clip); i++ {
-			v.cursor.Right()
-		}
+		v.cursor.SetLoc(v.cursor.Loc() + Count(clip))
 	} else {
 		messenger.Error("Clipboard is not supported on your system")
 	}
@@ -343,6 +340,7 @@ func (v *View) HandleEvent(event tcell.Event) {
 	relocate := true
 	// By default we don't update and syntax highlighting
 	v.UpdateLines(-2, 0)
+	rematch := true
 	switch e := event.(type) {
 	case *tcell.EventResize:
 		// Window resized
@@ -352,21 +350,26 @@ func (v *View) HandleEvent(event tcell.Event) {
 		case tcell.KeyUp:
 			// Cursor up
 			v.cursor.Up()
+			rematch = false
 		case tcell.KeyDown:
 			// Cursor down
 			v.cursor.Down()
+			rematch = false
 		case tcell.KeyLeft:
 			// Cursor left
 			v.cursor.Left()
+			rematch = false
 		case tcell.KeyRight:
 			// Cursor right
 			v.cursor.Right()
+			rematch = false
 		case tcell.KeyEnter:
 			// Insert a newline
 			v.eh.Insert(v.cursor.Loc(), "\n")
 			v.cursor.Right()
 			// Rehighlight the entire buffer
 			v.UpdateLines(v.topline, v.topline+v.height)
+			v.cursor.lastVisualX = v.cursor.GetVisualX()
 			// v.UpdateLines(v.cursor.y-1, v.cursor.y)
 		case tcell.KeySpace:
 			// Insert a space
@@ -396,6 +399,7 @@ func (v *View) HandleEvent(event tcell.Event) {
 				v.UpdateLines(v.topline, v.topline+v.height)
 				// v.UpdateLines(v.cursor.y, v.cursor.y+1)
 			}
+			v.cursor.lastVisualX = v.cursor.GetVisualX()
 		case tcell.KeyTab:
 			// Insert a tab
 			v.eh.Insert(v.cursor.Loc(), "\t")
@@ -415,6 +419,7 @@ func (v *View) HandleEvent(event tcell.Event) {
 			v.Copy()
 			// Rehighlight the entire buffer
 			v.UpdateLines(v.topline, v.topline+v.height)
+			rematch = false
 		case tcell.KeyCtrlX:
 			v.Cut()
 			// Rehighlight the entire buffer
@@ -509,6 +514,7 @@ func (v *View) HandleEvent(event tcell.Event) {
 				}
 			}
 			v.mouseReleased = false
+			rematch = false
 
 		case tcell.ButtonNone:
 			// Mouse event with no click
@@ -530,6 +536,7 @@ func (v *View) HandleEvent(event tcell.Event) {
 			// We don't want to relocate because otherwise the view will be relocated
 			// every time the user moves the cursor
 			relocate = false
+			rematch = false
 		case tcell.WheelUp:
 			// Scroll up two lines
 			v.ScrollUp(2)
@@ -551,7 +558,9 @@ func (v *View) HandleEvent(event tcell.Event) {
 		v.Relocate()
 	}
 
-	v.matches = Match(v)
+	if rematch {
+		v.matches = Match(v)
+	}
 }
 
 // DisplayView renders the view to the screen