Using `toUpperCase` or `textTransform: 'uppercase'` breaks on an Android controlled TextInput

React Native version: 0.61.4 and lower

Trying to force capitalization of characters inside a TextInput is broken on Android.

• autoCapitalize="characters" doesn’t seem to do anything
• Using toUpperCase in the onChangeText hook causes duplication of letters
• Using textTransform: 'uppercase' in styles block causes the same duplication of letters
• Using textTransform: 'uppercase' in a non-controlled TextInput does nothing

Steps To Reproduce

1. Create a controlled TextInput and either use onTextChanged to modify the text to uppercase or use text transform in the styles block
2. Type multiple lowercase characters into the text box

Describe what you expected to happen: Characters should be capitalized

What actually happens: Characters are capitalized and duplicated

Snack, code example, screenshot, or link to a repository: https://snack.expo.io/@nmi09/rn-android-capitalize-input-bug

[arthurolga]

autoCapitalize={'characters'} Seems to solve the problem. https://www.reddit.com/r/reactnative/comments/jhdref/any_solution_to_the_touppercase_problem

[simon-davies-avtura]

keyboardType={Platform.OS === 'ios' ? 'default' : 'visible-password'}

Seems to be the only workaround for me with Android at the moment (I’ve been looking for ages!). Will need some cross platform testing locally though.