Register insertionLocations to undoManager more properly

CHANGELOG.md

@@ -7,15 +7,16 @@ Change Log
 
 ### Improvements
 
-- [beta] Support `^T` and `fn+delete` (`^D`) shortcut multi-cursor editing.
+- [beta] Support `^T` and `fn+delete` (`^D`) shortcut in multi-cursor editing.
 
 
 ### Fixes
 
-- [beta] Fix an issue where multiple cursors disappeared after (auto-)saving with “trim tailing whitespace on save” option.
+- [beta] Fix an issue where multiple cursors disappeared after (auto-)saving with “trim trailing whitespace on save” option.
+- [beta] Fix an issue where the first cursor could disappear after some specific text editing.
 - [beta] Fix an issue where auto-inserted tab did not expand to spaces on auto indent level adjustment.
-- [beta] Fix multi-cursor behavior of deleting to the beginning of visual line by `⌘⌫`.
-- [beta] Fix multi-cusor movement when encounter a surrogate pair.
+- [beta] Fix multi-cursor behavior of deleting to the beginning of the visual line by `⌘⌫`.
+- [beta] Fix multi-cursor movement when encountering a surrogate pair.
 - [beta] Fix an issue where a selected range and an insertion point could overlap.
 
 

CotEditor/Sources/NSTextView+TextReplacement.swift

@@ -66,7 +66,7 @@ extension NSTextView {
         
         
         textStorage.beginEditing()
-        // use backwards enumeration to skip adjustment of applying location
+        // use a backward enumeration to skip adjustment of applying location
         for (string, range) in zip(strings, ranges).reversed() {
             let attrString = NSAttributedString(string: string, attributes: self.typingAttributes)
             
@@ -87,7 +87,16 @@ extension NSTextView {
     /// set undoable selection change
     func setSelectedRangesWithUndo(_ ranges: [NSValue]) {
         
-        self.selectedRanges = ranges
+        if let self = self as? NSTextView & MultiCursorEditing,
+            let ranges = ranges as? [NSRange],
+            let set = self.prepareForSelectionUpdate(ranges)
+        {
+            self.selectedRanges = set.selectedRanges
+            self.insertionLocations = set.insertionLocations
+            
+        } else {
+            self.selectedRanges = ranges
+        }
         
         self.undoManager?.registerUndo(withTarget: self) { target in
             target.setSelectedRangesWithUndo(ranges)
@@ -102,7 +111,7 @@ extension NSTextView {
     }
     
     
-    /// trim all trailing whitespace with/without keeeping editing point
+    /// trim all trailing whitespace with/without keeping editing point
     func trimTrailingWhitespace(ignoresEmptyLines: Bool, keepingEditingPoint: Bool = false) {
         
         assert(Thread.isMainThread)