From 8f4820ba28dc6cad6adbdfa405d1ce4a0ab7dfd3 Mon Sep 17 00:00:00 2001
From: Zachary Yedidia <zyedidia@gmail.com>
Date: Sun, 25 Jun 2017 19:14:01 -0400
Subject: [PATCH] Move cursor selections on Insert or Remove

Ref #715
---
 cmd/micro/buffer.go       |  2 +-
 cmd/micro/eventhandler.go | 34 ++++++++++++++++++++++++----------
 2 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/cmd/micro/buffer.go b/cmd/micro/buffer.go
index 6471baf0..258ea18b 100644
--- a/cmd/micro/buffer.go
+++ b/cmd/micro/buffer.go
@@ -316,7 +316,7 @@ func (b *Buffer) MergeCursors() {
 		if c1 != nil {
 			for j := 0; j < len(b.cursors); j++ {
 				c2 := b.cursors[j]
-				if i != j && c1.Loc == c2.Loc {
+				if c2 != nil && i != j && c1.Loc == c2.Loc {
 					b.cursors[j] = nil
 				}
 			}
diff --git a/cmd/micro/eventhandler.go b/cmd/micro/eventhandler.go
index 24bc593e..d50bdb0e 100644
--- a/cmd/micro/eventhandler.go
+++ b/cmd/micro/eventhandler.go
@@ -107,11 +107,19 @@ func (eh *EventHandler) Insert(start Loc, text string) {
 	end := e.Deltas[0].End
 
 	for _, c := range eh.buf.cursors {
-		if start.Y != end.Y && c.GreaterThan(start) {
-			c.Loc.Y += end.Y - start.Y
-		} else if c.Y == start.Y && c.GreaterEqual(start) {
-			c.Loc = c.Move(Count(text), eh.buf)
+		move := func(loc Loc) Loc {
+			if start.Y != end.Y && loc.GreaterThan(start) {
+				loc.Y += end.Y - start.Y
+			} else if loc.Y == start.Y && loc.GreaterEqual(start) {
+				loc = loc.Move(Count(text), eh.buf)
+			}
+			return loc
 		}
+		c.Loc = move(c.Loc)
+		c.CurSelection[0] = move(c.CurSelection[0])
+		c.CurSelection[1] = move(c.CurSelection[1])
+		c.OrigSelection[0] = move(c.OrigSelection[0])
+		c.OrigSelection[1] = move(c.OrigSelection[1])
 		c.LastVisualX = c.GetVisualX()
 	}
 }
@@ -127,13 +135,19 @@ func (eh *EventHandler) Remove(start, end Loc) {
 	eh.Execute(e)
 
 	for _, c := range eh.buf.cursors {
-		if start.Y != end.Y && c.GreaterThan(end) {
-			c.Loc.Y -= end.Y - start.Y
-		} else if c.Y == end.Y && c.GreaterEqual(end) {
-			// TermMessage(start, end)
-			c.Loc = c.Move(-Diff(start, end, eh.buf), eh.buf)
-			// c.Loc = c.Move(ToCharPos(start, eh.buf)-ToCharPos(end, eh.buf), eh.buf)
+		move := func(loc Loc) Loc {
+			if start.Y != end.Y && loc.GreaterThan(end) {
+				loc.Y -= end.Y - start.Y
+			} else if loc.Y == end.Y && loc.GreaterEqual(end) {
+				loc = loc.Move(-Diff(start, end, eh.buf), eh.buf)
+			}
+			return loc
 		}
+		c.Loc = move(c.Loc)
+		c.CurSelection[0] = move(c.CurSelection[0])
+		c.CurSelection[1] = move(c.CurSelection[1])
+		c.OrigSelection[0] = move(c.OrigSelection[0])
+		c.OrigSelection[1] = move(c.OrigSelection[1])
 		c.LastVisualX = c.GetVisualX()
 	}
 }