Too many bugs in composition mode

Do you want to request a feature or report a bug?

bug

What is the current behavior?

1. Input some chars use IME, then command + z to undo the chars, it will not work
2. Input two line text, select them all, use IME to input some chars, the second line would not be removed

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem. You can use this jsfiddle to get started: https://jsfiddle.net/gmertk/e61z7nfa/.

Just go to the official site to try: https://draftjs.org/

What is the expected behavior?

1. undo should work when input use IME
2. use IME should replace all selected lines

Which versions of Draft.js, and which browser / OS are affected by this issue? Did this work in previous versions of Draft.js?

version >= 0.11.0 all have these problems, I notice that you have changed the composition handler, that is the cause of these bugs.

like this: https://github.com/facebook/draft-js/blob/master/src/component/handlers/composition/DraftEditorCompositionHandler.js#L256, the author must be drunk when he write the code, EditorState.push has push the same contentState, this line of code just useless.