From 953f5a0eff873fe94ff6d946a18511bc580c873b Mon Sep 17 00:00:00 2001
From: Zachary Yedidia <zyedidia@gmail.com>
Date: Tue, 28 Jan 2020 20:54:14 -0500
Subject: [PATCH] Highlight in parallel

---
 cmd/micro/micro.go            | 19 ++++++++++++++--
 internal/buffer/buffer.go     | 13 ++++++++---
 internal/buffer/line_array.go | 42 +++++++++++++++++++++++++++++++----
 3 files changed, 65 insertions(+), 9 deletions(-)

diff --git a/cmd/micro/micro.go b/cmd/micro/micro.go
index 3e2f95fa..fb5ce220 100644
--- a/cmd/micro/micro.go
+++ b/cmd/micro/micro.go
@@ -7,6 +7,7 @@ import (
 	"os"
 	"runtime"
 	"sort"
+	"time"
 
 	"github.com/go-errors/errors"
 	isatty "github.com/mattn/go-isatty"
@@ -240,6 +241,22 @@ func main() {
 		}
 	}()
 
+	// clear the drawchan so we don't redraw excessively
+	// if someone requested a redraw before we started displaying
+	for len(screen.DrawChan) > 0 {
+		<-screen.DrawChan
+	}
+
+	var event tcell.Event
+
+	// wait for initial resize event
+	select {
+	case event = <-events:
+		action.Tabs.HandleEvent(event)
+	case <-time.After(20 * time.Millisecond):
+		// time out after 10ms
+	}
+
 	for {
 		// Display everything
 		screen.Screen.Fill(' ', config.DefStyle)
@@ -252,8 +269,6 @@ func main() {
 		action.InfoBar.Display()
 		screen.Screen.Show()
 
-		var event tcell.Event
-
 		// Check for new events
 		select {
 		case f := <-shell.Jobs:
diff --git a/internal/buffer/buffer.go b/internal/buffer/buffer.go
index e4af6be5..01fe167f 100644
--- a/internal/buffer/buffer.go
+++ b/internal/buffer/buffer.go
@@ -10,6 +10,7 @@ import (
 	"path/filepath"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 	"unicode/utf8"
 
@@ -117,6 +118,7 @@ type Buffer struct {
 	Highlighter *highlight.Highlighter
 	// Modifications is the list of modified regions for syntax highlighting
 	Modifications []Loc
+	HighlightLock sync.Mutex
 
 	// Hash of the original buffer -- empty if fastdirty is on
 	origHash [md5.Size]byte
@@ -610,7 +612,9 @@ func (b *Buffer) UpdateRules() {
 	}
 
 	if b.Highlighter == nil || syntaxFile != "" {
-		b.Settings["filetype"] = b.SyntaxDef.FileType
+		if b.SyntaxDef != nil {
+			b.Settings["filetype"] = b.SyntaxDef.FileType
+		}
 	} else {
 		b.SyntaxDef = &highlight.EmptyDef
 	}
@@ -618,8 +622,11 @@ func (b *Buffer) UpdateRules() {
 	if b.SyntaxDef != nil {
 		b.Highlighter = highlight.NewHighlighter(b.SyntaxDef)
 		if b.Settings["syntax"].(bool) {
-			b.Highlighter.HighlightStates(b)
-			b.Highlighter.HighlightMatches(b, 0, b.End().Y)
+			go func() {
+				b.Highlighter.HighlightStates(b)
+				b.Highlighter.HighlightMatches(b, 0, b.End().Y)
+				screen.DrawChan <- true
+			}()
 		}
 	}
 }
diff --git a/internal/buffer/line_array.go b/internal/buffer/line_array.go
index dcbf2e43..0aa69d7a 100644
--- a/internal/buffer/line_array.go
+++ b/internal/buffer/line_array.go
@@ -3,6 +3,7 @@ package buffer
 import (
 	"bufio"
 	"io"
+	"sync"
 	"unicode/utf8"
 
 	"github.com/zyedidia/micro/pkg/highlight"
@@ -38,6 +39,7 @@ type Line struct {
 	state       highlight.State
 	match       highlight.LineMatch
 	rehighlight bool
+	lock        sync.Mutex
 }
 
 const (
@@ -124,12 +126,22 @@ func NewLineArray(size uint64, endings FileFormat, reader io.Reader) *LineArray
 
 		if err != nil {
 			if err == io.EOF {
-				la.lines = Append(la.lines, Line{data[:], nil, nil, false})
+				la.lines = Append(la.lines, Line{
+					data:        data[:],
+					state:       nil,
+					match:       nil,
+					rehighlight: false,
+				})
 			}
 			// Last line was read
 			break
 		} else {
-			la.lines = Append(la.lines, Line{data[:dlen-1], nil, nil, false})
+			la.lines = Append(la.lines, Line{
+				data:        data[:dlen-1],
+				state:       nil,
+				match:       nil,
+				rehighlight: false,
+			})
 		}
 		n++
 	}
@@ -155,9 +167,19 @@ func (la *LineArray) Bytes() []byte {
 
 // newlineBelow adds a newline below the given line number
 func (la *LineArray) newlineBelow(y int) {
-	la.lines = append(la.lines, Line{[]byte{' '}, nil, nil, false})
+	la.lines = append(la.lines, Line{
+		data:        []byte{' '},
+		state:       nil,
+		match:       nil,
+		rehighlight: false,
+	})
 	copy(la.lines[y+2:], la.lines[y+1:])
-	la.lines[y+1] = Line{[]byte{}, la.lines[y].state, nil, false}
+	la.lines[y+1] = Line{
+		data:        []byte{},
+		state:       la.lines[y].state,
+		match:       nil,
+		rehighlight: false,
+	}
 }
 
 // Inserts a byte array at a given location
@@ -285,28 +307,40 @@ func (la *LineArray) LineBytes(n int) []byte {
 
 // State gets the highlight state for the given line number
 func (la *LineArray) State(lineN int) highlight.State {
+	la.lines[lineN].lock.Lock()
+	defer la.lines[lineN].lock.Unlock()
 	return la.lines[lineN].state
 }
 
 // SetState sets the highlight state at the given line number
 func (la *LineArray) SetState(lineN int, s highlight.State) {
+	la.lines[lineN].lock.Lock()
+	defer la.lines[lineN].lock.Unlock()
 	la.lines[lineN].state = s
 }
 
 // SetMatch sets the match at the given line number
 func (la *LineArray) SetMatch(lineN int, m highlight.LineMatch) {
+	la.lines[lineN].lock.Lock()
+	defer la.lines[lineN].lock.Unlock()
 	la.lines[lineN].match = m
 }
 
 // Match retrieves the match for the given line number
 func (la *LineArray) Match(lineN int) highlight.LineMatch {
+	la.lines[lineN].lock.Lock()
+	defer la.lines[lineN].lock.Unlock()
 	return la.lines[lineN].match
 }
 
 func (la *LineArray) Rehighlight(lineN int) bool {
+	la.lines[lineN].lock.Lock()
+	defer la.lines[lineN].lock.Unlock()
 	return la.lines[lineN].rehighlight
 }
 
 func (la *LineArray) SetRehighlight(lineN int, on bool) {
+	la.lines[lineN].lock.Lock()
+	defer la.lines[lineN].lock.Unlock()
 	la.lines[lineN].rehighlight = on
 }