Get undo working properly with multiple cursors

cmd/micro/actions.go

@@ -1848,6 +1848,7 @@ func (v *View) SpawnMultiCursor(usePlugin bool) bool {
 				}
 			}
 			v.Buf.cursors = append(v.Buf.cursors, c)
+			v.Buf.UpdateCursors()
 			v.Relocate()
 			v.Cursor = spawner
 		}
@@ -1879,6 +1880,7 @@ func (v *View) MouseMultiCursor(usePlugin bool, e *tcell.EventMouse) bool {
 		v.Cursor = &v.Buf.Cursor
 
 		v.Buf.cursors = append(v.Buf.cursors, c)
+		v.Buf.UpdateCursors()
 
 		if usePlugin {
 			PostActionCall("SpawnMultiCursorAtMouse", v)
@@ -1923,6 +1925,7 @@ func (v *View) RemoveMultiCursor(usePlugin bool) bool {
 			if end > 1 {
 				v.Buf.cursors[end-1] = nil
 				v.Buf.cursors = v.Buf.cursors[:end-1]
+				v.Buf.UpdateCursors()
 			}
 			v.Relocate()
 
@@ -1948,6 +1951,7 @@ func (v *View) RemoveAllMultiCursors(usePlugin bool) bool {
 			v.Buf.cursors[i] = nil
 		}
 		v.Buf.cursors = v.Buf.cursors[:1]
+		v.Buf.UpdateCursors()
 		v.Cursor.ResetSelection()
 		v.Relocate()
 

cmd/micro/buffer.go

@@ -28,8 +28,9 @@ type Buffer struct {
 	// This stores all the text in the buffer as an array of lines
 	*LineArray
 
-	Cursor  Cursor
-	cursors []*Cursor // for multiple cursors
+	Cursor    Cursor
+	cursors   []*Cursor // for multiple cursors
+	curCursor int       // the current cursor
 
 	// Path to the file on disk
 	Path string
@@ -308,6 +309,12 @@ func (b *Buffer) Update() {
 	b.NumLines = len(b.lines)
 }
 
+func (b *Buffer) UpdateCursors() {
+	for i, c := range b.cursors {
+		c.Num = i
+	}
+}
+
 // Save saves the buffer to its default path
 func (b *Buffer) Save() error {
 	return b.SaveAs(b.Path)

cmd/micro/cursor.go

@@ -21,6 +21,9 @@ type Cursor struct {
 	// This is used for line and word selection where it is necessary
 	// to know what the original selection was
 	OrigSelection [2]Loc
+
+	// Which cursor index is this (for multiple cursors)
+	Num int
 }
 
 // Goto puts the cursor at the given cursor's location and gives the current cursor its selection too

cmd/micro/eventhandler.go

@@ -97,7 +97,7 @@ func (eh *EventHandler) ApplyDiff(new string) {
 // Insert creates an insert text event and executes it
 func (eh *EventHandler) Insert(start Loc, text string) {
 	e := &TextEvent{
-		C:         eh.buf.Cursor,
+		C:         *eh.buf.cursors[eh.buf.curCursor],
 		EventType: TextEventInsert,
 		Deltas:    []Delta{Delta{text, start, Loc{0, 0}}},
 		Time:      time.Now(),
@@ -119,7 +119,7 @@ func (eh *EventHandler) Insert(start Loc, text string) {
 // Remove creates a remove text event and executes it
 func (eh *EventHandler) Remove(start, end Loc) {
 	e := &TextEvent{
-		C:         eh.buf.Cursor,
+		C:         *eh.buf.cursors[eh.buf.curCursor],
 		EventType: TextEventRemove,
 		Deltas:    []Delta{Delta{"", start, end}},
 		Time:      time.Now(),
@@ -141,7 +141,7 @@ func (eh *EventHandler) Remove(start, end Loc) {
 // MultipleReplace creates an multiple insertions executes them
 func (eh *EventHandler) MultipleReplace(deltas []Delta) {
 	e := &TextEvent{
-		C:         eh.buf.Cursor,
+		C:         *eh.buf.cursors[eh.buf.curCursor],
 		EventType: TextEventReplace,
 		Deltas:    deltas,
 		Time:      time.Now(),
@@ -216,8 +216,12 @@ func (eh *EventHandler) UndoOneEvent() {
 
 	// Set the cursor in the right place
 	teCursor := t.C
-	t.C = eh.buf.Cursor
-	eh.buf.Cursor.Goto(teCursor)
+	if teCursor.Num >= 0 && teCursor.Num < len(eh.buf.cursors) {
+		t.C = *eh.buf.cursors[teCursor.Num]
+		eh.buf.cursors[teCursor.Num].Goto(teCursor)
+	} else {
+		teCursor.Num = -1
+	}
 
 	// Push it to the redo stack
 	eh.RedoStack.Push(t)
@@ -259,8 +263,12 @@ func (eh *EventHandler) RedoOneEvent() {
 	UndoTextEvent(t, eh.buf)
 
 	teCursor := t.C
-	t.C = eh.buf.Cursor
-	eh.buf.Cursor.Goto(teCursor)
+	if teCursor.Num >= 0 && teCursor.Num < len(eh.buf.cursors) {
+		t.C = *eh.buf.cursors[teCursor.Num]
+		eh.buf.cursors[teCursor.Num].Goto(teCursor)
+	} else {
+		teCursor.Num = -1
+	}
 
 	eh.UndoStack.Push(t)
 }

cmd/micro/view.go

@@ -479,6 +479,11 @@ func (v *View) ExecuteActions(actions []func(*View, bool) bool) bool {
 	return relocate
 }
 
+func (v *View) SetCursor(c *Cursor) {
+	v.Cursor = c
+	v.Buf.curCursor = c.Num
+}
+
 // HandleEvent handles an event passed by the main loop
 func (v *View) HandleEvent(event tcell.Event) {
 	// This bool determines whether the view is relocated at the end of the function
@@ -500,12 +505,12 @@ func (v *View) HandleEvent(event tcell.Event) {
 				}
 				if e.Modifiers() == key.modifiers {
 					for _, c := range v.Buf.cursors {
-						v.Cursor = c
+						v.SetCursor(c)
 						relocate = false
 						isBinding = true
 						relocate = v.ExecuteActions(actions) || relocate
 					}
-					v.Cursor = &v.Buf.Cursor
+					v.SetCursor(&v.Buf.Cursor)
 					break
 				}
 			}
@@ -514,7 +519,7 @@ func (v *View) HandleEvent(event tcell.Event) {
 			// Check viewtype if readonly don't insert a rune (readonly help and log view etc.)
 			if v.Type.readonly == false {
 				for _, c := range v.Buf.cursors {
-					v.Cursor = c
+					v.SetCursor(c)
 
 					// Insert a character
 					if v.Cursor.HasSelection() {
@@ -534,7 +539,7 @@ func (v *View) HandleEvent(event tcell.Event) {
 						curMacro = append(curMacro, e.Rune())
 					}
 				}
-				v.Cursor = &v.Buf.Cursor
+				v.SetCursor(&v.Buf.Cursor)
 			}
 		}
 	case *tcell.EventPaste:
@@ -545,11 +550,11 @@ func (v *View) HandleEvent(event tcell.Event) {
 			}
 
 			for _, c := range v.Buf.cursors {
-				v.Cursor = c
+				v.SetCursor(c)
 				v.paste(e.Text())
 
 			}
-			v.Cursor = &v.Buf.Cursor
+			v.SetCursor(&v.Buf.Cursor)
 
 			PostActionCall("Paste", v)
 		}
@@ -562,10 +567,10 @@ func (v *View) HandleEvent(event tcell.Event) {
 		for key, actions := range bindings {
 			if button == key.buttons && e.Modifiers() == key.modifiers {
 				for _, c := range v.Buf.cursors {
-					v.Cursor = c
+					v.SetCursor(c)
 					relocate = v.ExecuteActions(actions) || relocate
 				}
-				v.Cursor = &v.Buf.Cursor
+				v.SetCursor(&v.Buf.Cursor)
 			}
 		}
 
@@ -841,7 +846,7 @@ func (v *View) DisplayView() {
 
 				charLoc := char.realLoc
 				for _, c := range v.Buf.cursors {
-					v.Cursor = c
+					v.SetCursor(c)
 					if v.Cursor.HasSelection() &&
 						(charLoc.GreaterEqual(v.Cursor.CurSelection[0]) && charLoc.LessThan(v.Cursor.CurSelection[1]) ||
 							charLoc.LessThan(v.Cursor.CurSelection[0]) && charLoc.GreaterEqual(v.Cursor.CurSelection[1])) {
@@ -853,7 +858,7 @@ func (v *View) DisplayView() {
 						}
 					}
 				}
-				v.Cursor = &v.Buf.Cursor
+				v.SetCursor(&v.Buf.Cursor)
 
 				if v.Buf.Settings["cursorline"].(bool) && tabs[curTab].CurView == v.Num &&
 					!v.Cursor.HasSelection() && v.Cursor.Y == realLineN {
@@ -865,14 +870,14 @@ func (v *View) DisplayView() {
 				screen.SetContent(xOffset+char.visualLoc.X, yOffset+char.visualLoc.Y, char.drawChar, nil, lineStyle)
 
 				for i, c := range v.Buf.cursors {
-					v.Cursor = c
+					v.SetCursor(c)
 					if tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() &&
 						v.Cursor.Y == char.realLoc.Y && v.Cursor.X == char.realLoc.X && (!cursorSet || i != 0) {
 						ShowMultiCursor(xOffset+char.visualLoc.X, yOffset+char.visualLoc.Y, i)
 						cursorSet = true
 					}
 				}
-				v.Cursor = &v.Buf.Cursor
+				v.SetCursor(&v.Buf.Cursor)
 
 				lastChar = char
 			}
@@ -885,26 +890,26 @@ func (v *View) DisplayView() {
 		if lastChar != nil {
 			lastX = xOffset + lastChar.visualLoc.X + lastChar.width
 			for i, c := range v.Buf.cursors {
-				v.Cursor = c
+				v.SetCursor(c)
 				if tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() &&
 					v.Cursor.Y == lastChar.realLoc.Y && v.Cursor.X == lastChar.realLoc.X+1 {
 					ShowMultiCursor(lastX, yOffset+lastChar.visualLoc.Y, i)
 					cx, cy = lastX, yOffset+lastChar.visualLoc.Y
 				}
 			}
-			v.Cursor = &v.Buf.Cursor
+			v.SetCursor(&v.Buf.Cursor)
 			realLoc = Loc{lastChar.realLoc.X + 1, realLineN}
 			visualLoc = Loc{lastX - xOffset, lastChar.visualLoc.Y}
 		} else if len(line) == 0 {
 			for i, c := range v.Buf.cursors {
-				v.Cursor = c
+				v.SetCursor(c)
 				if tabs[curTab].CurView == v.Num && !v.Cursor.HasSelection() &&
 					v.Cursor.Y == realLineN {
 					ShowMultiCursor(xOffset, yOffset+visualLineN, i)
 					cx, cy = xOffset, yOffset+visualLineN
 				}
 			}
-			v.Cursor = &v.Buf.Cursor
+			v.SetCursor(&v.Buf.Cursor)
 			lastX = xOffset
 			realLoc = Loc{0, realLineN}
 			visualLoc = Loc{0, visualLineN}