Make CEUndoManager public (#212)

Author: avinizhanov

Sources/CodeEditTextView/CodeEditTextView.swift

@@ -35,6 +35,7 @@ public struct CodeEditTextView: NSViewControllerRepresentable {
     ///                    character's width between characters, etc. Defaults to `1.0`
     ///   - bracketPairHighlight: The type of highlight to use to highlight bracket pairs.
     ///                           See `BracketPairHighlight` for more information. Defaults to `nil`
+    ///   - undoManager: The undo manager for the text view. Defaults to `nil`, which will create a new CEUndoManager
     public init(
         _ text: Binding<String>,
         language: CodeLanguage,
@@ -51,7 +52,8 @@ public struct CodeEditTextView: NSViewControllerRepresentable {
         contentInsets: NSEdgeInsets? = nil,
         isEditable: Bool = true,
         letterSpacing: Double = 1.0,
-        bracketPairHighlight: BracketPairHighlight? = nil
+        bracketPairHighlight: BracketPairHighlight? = nil,
+        undoManager: CEUndoManager? = nil
     ) {
         self._text = text
         self.language = language
@@ -69,6 +71,7 @@ public struct CodeEditTextView: NSViewControllerRepresentable {
         self.isEditable = isEditable
         self.letterSpacing = letterSpacing
         self.bracketPairHighlight = bracketPairHighlight
+        self.undoManager = undoManager ?? CEUndoManager()
     }
 
     @Binding private var text: String
@@ -87,6 +90,7 @@ public struct CodeEditTextView: NSViewControllerRepresentable {
     private var isEditable: Bool
     private var letterSpacing: Double
     private var bracketPairHighlight: BracketPairHighlight?
+    private var undoManager: CEUndoManager
 
     public typealias NSViewControllerType = STTextViewController
 
@@ -107,7 +111,8 @@ public struct CodeEditTextView: NSViewControllerRepresentable {
             contentInsets: contentInsets,
             isEditable: isEditable,
             letterSpacing: letterSpacing,
-            bracketPairHighlight: bracketPairHighlight
+            bracketPairHighlight: bracketPairHighlight,
+            undoManager: undoManager
         )
         return controller
     }

Sources/CodeEditTextView/Controller/CEUndoManager.swift

@@ -16,30 +16,30 @@ import TextStory
 /// - Grouping pasted text
 ///
 /// If needed, the automatic undo grouping can be overridden using the `beginGrouping()` and `endGrouping()` methods.
-class CEUndoManager {
+public class CEUndoManager {
     /// An `UndoManager` subclass that forwards relevant actions to a `CEUndoManager`.
     /// Allows for objects like `STTextView` to use the `UndoManager` API
     /// while CETV manages the undo/redo actions.
-    class DelegatedUndoManager: UndoManager {
+    public class DelegatedUndoManager: UndoManager {
         weak var parent: CEUndoManager?
 
-        override var canUndo: Bool { parent?.canUndo ?? false }
-        override var canRedo: Bool { parent?.canRedo ?? false }
+        public override var canUndo: Bool { parent?.canUndo ?? false }
+        public override var canRedo: Bool { parent?.canRedo ?? false }
 
-        func registerMutation(_ mutation: TextMutation) {
+        public func registerMutation(_ mutation: TextMutation) {
             parent?.registerMutation(mutation)
             removeAllActions()
         }
 
-        override func undo() {
+        public override func undo() {
             parent?.undo()
         }
 
-        override func redo() {
+        public override func redo() {
             parent?.redo()
         }
 
-        override func registerUndo(withTarget target: Any, selector: Selector, object anObject: Any?) {
+        public override func registerUndo(withTarget target: Any, selector: Selector, object anObject: Any?) {
             // no-op, but just in case to save resources:
             removeAllActions()
         }
@@ -71,36 +71,41 @@ class CEUndoManager {
     /// A stack of operations that can be redone.
     private var redoStack: [UndoGroup] = []
 
-    private unowned let textView: STTextView
+    internal weak var textView: STTextView?
     private(set) var isGrouping: Bool = false
 
-    public init(textView: STTextView) {
-        self.textView = textView
+    public init() {
         self.manager = DelegatedUndoManager()
         manager.parent = self
     }
 
     /// Performs an undo operation if there is one available.
     public func undo() {
-        guard let item = undoStack.popLast() else {
+        guard let item = undoStack.popLast(),
+              let textView else {
             return
         }
         isUndoing = true
         for mutation in item.mutations.reversed() {
+            NotificationCenter.default.post(name: .NSUndoManagerWillUndoChange, object: self.manager)
             textView.applyMutationNoUndo(mutation.inverse)
+            NotificationCenter.default.post(name: .NSUndoManagerDidUndoChange, object: self.manager)
         }
         redoStack.append(item)
         isUndoing = false
     }
 
     /// Performs a redo operation if there is one available.
     public func redo() {
-        guard let item = redoStack.popLast() else {
+        guard let item = redoStack.popLast(),
+              let textView else {
             return
         }
         isRedoing = true
         for mutation in item.mutations {
+            NotificationCenter.default.post(name: .NSUndoManagerWillRedoChange, object: self.manager)
             textView.applyMutationNoUndo(mutation.mutation)
+            NotificationCenter.default.post(name: .NSUndoManagerDidRedoChange, object: self.manager)
         }
         undoStack.append(item)
         isRedoing = false
@@ -117,6 +122,8 @@ class CEUndoManager {
     /// Calling this method while the manager is in an undo/redo operation will result in a no-op.
     /// - Parameter mutation: The mutation to register for undo/redo
     public func registerMutation(_ mutation: TextMutation) {
+        guard let textView else { return }
+
         if (mutation.range.length == 0 && mutation.string.isEmpty) || isUndoing || isRedoing { return }
         let newMutation = UndoGroup.Mutation(mutation: mutation, inverse: textView.inverseMutation(for: mutation))
         if !undoStack.isEmpty, let lastMutation = undoStack.last?.mutations.last {

Sources/CodeEditTextView/Controller/STTextViewController+Lifecycle.swift

@@ -57,7 +57,7 @@ extension STTextViewController {
             return event
         }
 
-        textViewUndoManager = CEUndoManager(textView: textView)
+        textViewUndoManager.textView = textView
         reloadUI()
         setUpHighlighter()
         setHighlightProvider(self.highlightProvider)

Sources/CodeEditTextView/Controller/STTextViewController.swift

@@ -27,7 +27,7 @@ public class STTextViewController: NSViewController, STTextViewDelegate, ThemeAt
     /// for every new selection.
     internal var lastTextSelections: [NSTextRange] = []
 
-    internal var textViewUndoManager: CEUndoManager!
+    internal var textViewUndoManager: CEUndoManager
 
     /// Binding for the `textView`s string
     public var text: Binding<String>
@@ -133,7 +133,8 @@ public class STTextViewController: NSViewController, STTextViewDelegate, ThemeAt
         contentInsets: NSEdgeInsets? = nil,
         isEditable: Bool,
         letterSpacing: Double,
-        bracketPairHighlight: BracketPairHighlight? = nil
+        bracketPairHighlight: BracketPairHighlight? = nil,
+        undoManager: CEUndoManager
     ) {
         self.text = text
         self.language = language
@@ -150,6 +151,7 @@ public class STTextViewController: NSViewController, STTextViewDelegate, ThemeAt
         self.contentInsets = contentInsets
         self.isEditable = isEditable
         self.bracketPairHighlight = bracketPairHighlight
+        self.textViewUndoManager = undoManager
         super.init(nibName: nil, bundle: nil)
     }
 

Tests/CodeEditTextViewTests/STTextViewControllerTests.swift

@@ -42,7 +42,8 @@ final class STTextViewControllerTests: XCTestCase {
             editorOverscroll: 0.5,
             useThemeBackground: true,
             isEditable: true,
-            letterSpacing: 1.0
+            letterSpacing: 1.0,
+            undoManager: CEUndoManager()
         )
 
         controller.loadView()