[MemberExpression] Brackets are required when calling a method on a number

Really excited about Prettier! I just ran it against our codebase here at Geckoboard and discovered a few edge case bugs. I’ll open issues for each of the bugs that I can generate a small repro case for.

You can call methods on a number using the following syntax:

(0).toLocaleString();

Prettier currently converts this to:

0.toLocaleString();

Which gives the following syntax error when run in Chrome:

Uncaught SyntaxError: Invalid or unexpected token

I would have expected the output to be:

(0).toLocaleString();

https://vjeux.github.io/prettier-browser/#{"content"%3A"(0).toLocaleString()%3B"%2C"options"%3A{"printWidth"%3A80%2C"tabWidth"%3A2%2C"useFlowParser"%3Afalse%2C"singleQuote"%3Afalse%2C"trailingComma"%3Afalse%2C"bracketSpacing"%3Afalse}}

[vjeux]

This is now fixed in 0.0.9

[vjeux]

needsParens is not being called for the binary expression. I think that it’s because printMemberChain somehow skips it but I don’t understand enough of how it works to be sure.