help.md

a(
  SomethingVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryLong,
  [
    {
      SomethingVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryLong: 1
    }
  ]
);

If you run this on master (or after #927) it prints

a(
  SomethingVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryLong,
  [{
      SomethingVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryLong: 1
    }]
);

In src/printer.js,

replace

concat(["(", join(concat([", "]), printedLastArgExpanded), ")"]),

by

concat(["(", join(concat([", "]), printed), ")"]),

and see that the output is now the correct

a(
  SomethingVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryLong,
  [
    {
      SomethingVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryVeryLong: 1
    }
  ]
);

but but but but, this isn't actually printing this line, it's still printing the last argument of the conditionalGroup.

What I don't understand is why changing the first group of a conditionalGroup changes, which doesn't end up being used, changes the behavior of the last one.