fix(input): gate prior tone change with preference

Author: zonble

Source/Engine/Mandarin/Mandarin.h

@@ -458,16 +458,6 @@ class BopomofoReadingBuffer {
 
   const BPMF syllable() const { return syllable_; }
 
-  void setSyllableRemovingTone(BPMF syllable) {
-    BPMF::Component masked = (syllable.consonantComponent() |
-                               syllable.middleVowelComponent() |
-                               syllable.vowelComponent());
-    syllable_ = BPMF(masked);
-    if (pinyin_mode_) {
-      pinyin_sequence_ = syllable_.HanyuPinyinString(false, false);
-    }
-  }
-
   const std::string standardLayoutQueryString() const {
     return BopomofoKeyboardLayout::StandardLayout()->keySequenceFromSyllable(
         syllable_);

Source/KeyHandler.mm

@@ -468,13 +468,20 @@ - (BOOL)handleInput:(KeyHandlerInput *)input state:(InputState *)inState stateCa
     //
     // This allows users to use tone key to change an existing reading before
     // the current cursor.
-    if (_bpmfReadingBuffer->hasToneMarkerOnly() && _grid->readings().size() > 0 && _grid->cursor() > 0) {
+    if (Preferences.allowChangingPriorTone &&
+        _bpmfReadingBuffer->hasToneMarkerOnly() &&
+        _grid->readings().size() > 0 &&
+        _grid->cursor() > 0) {
         size_t cursor = _grid->cursor() - 1;
-        const std::string reading = _grid->readings()[cursor];
+//        const std::string reading = _grid->readings()[cursor];
+        const std::string& reading = _grid->readings()[cursor];
         if (!reading.empty() && reading[0] != '_') {
             Formosa::Mandarin::BopomofoReadingBuffer tmpBuffer(_bpmfReadingBuffer->keyboardLayout());
-            Formosa::Mandarin::BopomofoSyllable syllable =      Formosa::Mandarin::BopomofoSyllable::FromComposedString(reading);
-            tmpBuffer.setSyllableRemovingTone(syllable);
+            Formosa::Mandarin::BopomofoSyllable syllable = Formosa::Mandarin::BopomofoSyllable::FromComposedString(reading);
+            std::string keys = _bpmfReadingBuffer->keyboardLayout()->keySequenceFromSyllable(syllable);
+            for (char k:keys) {
+                tmpBuffer.combineKey(k);
+            }
             tmpBuffer.combineKey((char)charCode);
             std::string newReading = tmpBuffer.syllable().composedString();
             if (_languageModel->hasUnigrams(newReading)) {

Source/Preferences.swift

@@ -74,6 +74,7 @@ private let kBig5InputEnabledKey = "Big5InputEnabled"
 let kBeepUponInputErrorKey = "BeepUponInputError"
 
 private let kEnableUserPhrasesInPlainBopomofo = "EnableUserPhrasesInPlainBopomofo"
+private let kAllowChangingPriorTone = "AllowChangingPriorTone"
 
 // MARK: Property wrappers
 
@@ -570,6 +571,11 @@ extension Preferences {
     @objc static var enableUserPhrasesInPlainBopomofo: Bool
 }
 
+extension Preferences {
+    @UserDefault(key: kAllowChangingPriorTone, defaultValue: false)
+    @objc static var allowChangingPriorTone: Bool
+}
+
 extension Preferences {
     static func createReport() -> String {
         var lines: [String] = []