refmt removes necessary parenthesis

[vkammerer]

I don't know where an issue with refmt should be filed, so I apologize in advance if it should be posted elsewhere.

I was reading through http://reasonmlhub.com/exploring-reasonml/ch_functions.html (the section "Compatibility of function types with labeled parameters"), and trying to reproduce the examples locally when I encountered what seems to be a bug with refmt's handling of parenthesis.

Steps to reproduce:

• go to https://reasonml.github.io/en/try.html?rrjsx=true&reason=DYUwLgBAhgJjEF4IAoB+APANBVBPAlIgHwToQDUEuA3AFCiQDGUwwAggGICuAdgOoBLMAAsArGx4wATIhRRuPAFwo06ZQJ5hsedZsIISGsPn0l5vZKOxT8dWgCkAzgDpgAewDmyZq069BIuKSUsiwMCZ0QA
• as you can see, reason compiles correctly and the browser console logs the expected output.
• click on "refmt" and see how parenthesis are removed from the function's definition
• Trigger recompilation by adding a line break at the end
• reason cannot compile the code anymore and logs an error

[IwanKaramazow]

Hi @vkammerer. If you have issues with refmt, you can file them at https://github.com/facebook/reason/issues. This is indeed a legit issue, I'll fix it.

[vkammerer]

Duplicate of https://github.com/facebook/reason/issues/1957