Extend TextProcessing with receive/lose focus callbacks

Proton/Sources/Swift/Editor/EditorView.swift

@@ -1451,10 +1451,14 @@ extension EditorView: RichTextViewDelegate {
     }
 
     func richTextView(_ richTextView: RichTextView, didReceiveFocusAt range: NSRange) {
+        let executableProcessors = textProcessor?.filteringExecutableOn(editor: self) ?? []
+        executableProcessors.forEach { $0.didReceiveFocus(editor: self) }
         AggregateEditorViewDelegate.editor(self, didReceiveFocusAt: range)
     }
 
     func richTextView(_ richTextView: RichTextView, didLoseFocusFrom range: NSRange) {
+        let executableProcessors = textProcessor?.filteringExecutableOn(editor: self) ?? []
+        executableProcessors.forEach { $0.didLoseFocus(editor: self) }
         AggregateEditorViewDelegate.editor(self, didLoseFocusFrom: range)
     }
 

Proton/Sources/Swift/TextProcessors/TextProcessing.swift

@@ -104,6 +104,16 @@ public protocol TextProcessing {
     ///   - newRange: Current range after the change
     func selectedRangeChanged(editor: EditorView, oldRange: NSRange?, newRange: NSRange?)
 
+    /// Notifies the processor when `editor` receives focus.
+    /// - Note: This function is also called when focus moves between `EditorView`'s nested editors.
+    /// - Parameter editor: `EditorView` which received focus
+    func didReceiveFocus(editor: EditorView)
+
+    /// Notifies the processor when `editor` loses focus.
+    /// - Note: This function is also called when focus moves between `EditorView`'s nested editors.
+    /// - Parameter editor: `EditorView` which lost focus
+    func didLoseFocus(editor: EditorView)
+
     /// Invoked after the text has been processed in the `Editor`.
     /// - Parameter editor: EditorView in which text is changed.
     func didProcess(editor: EditorView)
@@ -134,4 +144,6 @@ public extension TextProcessing {
     func shouldProcess(_ editorView: EditorView, shouldProcessTextIn range: NSRange, replacementText text: String) -> Bool { return true }
     func willProcessEditing(editor: EditorView, editedMask: NSTextStorage.EditActions, range editedRange: NSRange, changeInLength delta: Int) { }
     func didProcessEditing(editor: EditorView, editedMask: NSTextStorage.EditActions, range editedRange: NSRange, changeInLength delta: Int) { }
+    func didReceiveFocus(editor: EditorView) { }
+    func didLoseFocus(editor: EditorView) { }
 }

Proton/Tests/Editor/EditorViewDelegateTests.swift

@@ -133,6 +133,38 @@ class EditorViewDelegateTests: XCTestCase {
         try assertKeyPress(.tab, replacementText: "\t")
     }
 
+    func testNotifiesTextProcessorsOnDidReceiveFocus() {
+        let expectation = functionExpectation()
+        let mockProcessor = MockTextProcessor()
+        mockProcessor.onDidReceiveFocus = { _ in
+            expectation.fulfill()
+        }
+        let editor = EditorView()
+        editor.textProcessor?.register(mockProcessor)
+        let richTextView = editor.richTextView
+        let richTextViewDelegate = richTextView.richTextViewDelegate
+
+        richTextViewDelegate?.richTextView(richTextView, didReceiveFocusAt: .zero)
+
+        waitForExpectations(timeout: 1.0)
+    }
+
+    func testNotifiesTextProcessorsOnDidLoseFocus() {
+        let expectation = functionExpectation()
+        let mockProcessor = MockTextProcessor()
+        mockProcessor.onDidLoseFocus = { _ in
+            expectation.fulfill()
+        }
+        let editor = EditorView()
+        editor.textProcessor?.register(mockProcessor)
+        let richTextView = editor.richTextView
+        let richTextViewDelegate = richTextView.richTextViewDelegate
+
+        richTextViewDelegate?.richTextView(richTextView, didLoseFocusFrom: .zero)
+
+        waitForExpectations(timeout: 1.0)
+    }
+
     private func assertKeyPress(_ key: EditorKey, replacementText: String, file: StaticString = #file, line: UInt = #line) throws {
         let delegateExpectation = functionExpectation()
         let delegate = MockEditorViewDelegate()

Proton/Tests/TextProcessors/Mocks/MockTextProcessor.swift

@@ -33,6 +33,8 @@ class MockTextProcessor: TextProcessing {
     var onKeyWithModifier: ((EditorView, EditorKey, UIKeyModifierFlags, NSRange) -> Void)?
     var onProcessInterrupted: ((EditorView, NSRange) -> Void)?
     var onSelectedRangeChanged: ((EditorView, NSRange?, NSRange?) -> Void)?
+    var onDidReceiveFocus: ((EditorView) -> Void)?
+    var onDidLoseFocus: ((EditorView) -> Void)?
     var onDidProcess: ((EditorView) -> Void)?
     var onShouldProcess: ((EditorView, NSRange, String) -> Bool)?
 
@@ -72,6 +74,14 @@ class MockTextProcessor: TextProcessing {
         onSelectedRangeChanged?(editor, oldRange, newRange)
     }
 
+    func didReceiveFocus(editor: EditorView) {
+        onDidReceiveFocus?(editor)
+    }
+
+    func didLoseFocus(editor: EditorView) {
+        onDidLoseFocus?(editor)
+    }
+
     func didProcess(editor: EditorView) {
         onDidProcess?(editor)
     }

Proton/Tests/TextProcessors/TextProcessorTests.swift

@@ -138,6 +138,28 @@ class TextProcessorTests: XCTestCase {
         waitForExpectations(timeout: 1.0)
     }
 
+    func testPreventsDidReceiveFocusOnSetAttributedText() throws {
+        let expectation = expectation(description: "Should not invoke didReceiveFocus")
+        expectation.isInverted = true
+        try assertProcessorInvocationOnSetAttributedText(expectation, isRunOnSettingText: false) { mockProcessor in
+            mockProcessor.onDidReceiveFocus = { _ in
+                expectation.fulfill()
+            }
+        }
+        waitForExpectations(timeout: 1.0)
+    }
+
+    func testPreventsDidLoseFocusOnSetAttributedText() throws {
+        let expectation = expectation(description: "Should not invoke didLoseFocus")
+        expectation.isInverted = true
+        try assertProcessorInvocationOnSetAttributedText(expectation, isRunOnSettingText: false) { mockProcessor in
+            mockProcessor.onDidLoseFocus = { _ in
+                expectation.fulfill()
+            }
+        }
+        waitForExpectations(timeout: 1.0)
+    }
+
     func testInvokesTextProcessor() {
         let testExpectation = functionExpectation()
         let editor = EditorView()