[Android] Fix letters duplication when using autoCapitalize

ReactAndroid/src/main/java/com/facebook/react/views/textinput/ReactEditText.java

@@ -111,6 +111,7 @@ public class ReactEditText extends AppCompatEditText
   private int mFontStyle = ReactTypefaceUtils.UNSET;
   private boolean mAutoFocus = false;
   private boolean mDidAttachToWindow = false;
+  private Integer mMaximumTextLength = 0;
 
   private ReactViewBackgroundManager mReactBackgroundManager;
 
@@ -331,7 +332,9 @@ public void maybeSetSelection(int eventCounter, int start, int end) {
     }
 
     if (start != UNSET && end != UNSET) {
-      setSelection(start, end);
+      int validStart = (start > mMaximumTextLength) ? mMaximumTextLength : start;
+      int validEnd = (end > mMaximumTextLength) ? mMaximumTextLength : end;
+      setSelection(validStart, validEnd);
     }
   }
 
@@ -510,6 +513,7 @@ public boolean canUpdateWithEventCount(int eventCounter) {
 
   // VisibleForTesting from {@link TextInputEventsTestCase}.
   public void maybeSetText(ReactTextUpdate reactTextUpdate) {
+    mMaximumTextLength = reactTextUpdate.getText().length();
     if (isSecureText() && TextUtils.equals(getText(), reactTextUpdate.getText())) {
       return;
     }
@@ -553,7 +557,11 @@ public void maybeSetText(ReactTextUpdate reactTextUpdate) {
       // When we update text, we trigger onChangeText code that will
       // try to update state if the wrapper is available. Temporarily disable
       // to prevent an infinite loop.
-      getText().replace(0, length(), spannableStringBuilder);
+      Integer startPosition = getSelectionStart();
+      Integer endPosition = getSelectionEnd();
+      setText(spannableStringBuilder);
+      mMaximumTextLength = spannableStringBuilder.length();
+      maybeSetSelection(mNativeEventCount, startPosition, endPosition);
     }
     mDisableTextDiffing = false;
 

packages/rn-tester/js/examples/TextInput/TextInputSharedExamples.js

@@ -104,7 +104,7 @@ class RewriteExample extends React.Component<$FlowFixMeProps, any> {
           multiline={false}
           maxLength={limit}
           onChangeText={text => {
-            text = text.replace(/ /g, '_');
+            text = text.replace(/ /g, '_').toUpperCase();
             this.setState({text});
           }}
           style={styles.default}