Fix a bug where typing and delete a single space hid the placeholder.

Author: pixlwave

.gitignore

@@ -1,6 +1,7 @@
 # ENV
 **/.python-version
 **/.vscode
+**/.idea
 **/.DS_Store
 # Generated
 /target/

platforms/ios/lib/WysiwygComposer/Sources/HTMLParser/Extensions/NSAttributedString+Range.swift

@@ -79,6 +79,15 @@ extension NSAttributedString {
     ///   - range: the range on which the elements should be detected. Entire range if omitted
     /// - Returns: an array of matching ranges
     func discardableTextRanges(in range: NSRange? = nil) -> [NSRange] {
+        // When typing a space into an empty composer, the single space being disposable results in
+        // `applyReplaceAll` failing, leaving attributedContent out of sync. The reconciliation then
+        // adds a second space to the model that isn't in the text view.
+        if string == .zwsp {
+            // This fixes that, although it doesn't help in the case of adding a single space to e.g.
+            // a list/quote where the same result can be seen with the model having an extra space.
+            return []
+        }
+        
         var ranges = [NSRange]()
 
         enumerateTypedAttribute(.discardableText, in: range) { (isDiscardable: Bool, range: NSRange, _) in

platforms/ios/lib/WysiwygComposer/Tests/WysiwygComposerTests/Components/WysiwygComposerView/WysiwygComposerViewModelTests.swift

@@ -41,6 +41,21 @@ final class WysiwygComposerViewModelTests: XCTestCase {
         viewModel.textView.attributedText = viewModel.attributedContent.text
         waitExpectation(expectation: expectTrue, timeout: 2.0)
     }
+    
+    func testIsContentEmptyAfterDeletingSingleSpace() {
+        // When typing a single space.
+        _ = viewModel.replaceText(range: .zero, replacementText: " ")
+        viewModel.textView.attributedText = NSAttributedString(string: " ")
+        viewModel.didUpdateText()
+        
+        // And then deleting that space.
+        _ = viewModel.replaceText(range: .init(location: 0, length: 1), replacementText: "")
+        viewModel.textView.attributedText = NSAttributedString(string: "")
+        viewModel.didUpdateText()
+        
+        // Then the content should be empty for the placeholder to be shown.
+        XCTAssertTrue(viewModel.isContentEmpty)
+    }
 
     func testSimpleTextInputIsAccepted() throws {
         let shouldChange = viewModel.replaceText(range: .zero,