Inline jsx with function expressions (single arg callback)

What refmt gives me:

      <input
        onChange=(
          self.reduce(
            (event) => {
              let text = ReactDOMRe.domElementToObj(ReactEventRe.Form.target(event))##value;
              Search(text)
            }
          )
        )
        value=self.state.search
     />

What I actually want:

      <input
        onChange=(self.reduce((event) => {
            let text = ReactDOMRe.domElementToObj(ReactEventRe.Form.target(event))##value;
            Search(text)
            }
          )
        )
        value=self.state.search
      />

The issue provides paired refmt input and desired output but names no source file or test. Start by reproducing the JSX formatting example with refmt, then trace the formatter's handling of inline function expressions with a single-argument callback. Done means the output matches the requested layout without changing the code's meaning.