PreferCurlyFors generates illegal code (and it isn't curly either)

[SethTisue]

• Version: 3.0.0
• Integration: Coursier launcher
• Configuration:

  version = 3.0.0
  rewrite.rules = [ PreferCurlyFors ]

Steps

Given code like this:

object O {
  for (pos <- "a->1|b->2".split('|'); c = pos.split("->"))
  yield ()
}

When I run scalafmt like this:

scalafmt --config scalafmt.conf S.scala

Problem

Scalafmt formats code like this:

object O {
  for (
    pos <- "a->1|b->2".split('|')
    c = pos.split("->")
  )
    yield ()
}

which the compiler then actually rejects:

% scalac S.scala
S.scala:4: error: value c is not a member of Array[String]
possible cause: maybe a semicolon is missing before `value c`?
    c = pos.split("->")
    ^
1 error

Expectation

I would like the formatted output to look like this:

object O {
  for {
    pos <- "a->1|b->2".split('|')
    c = pos.split("->")
  }
    yield ()
}

Notes

this came up over at https://github.com/playframework/twirl/pull/437

[SethTisue]

thank you for the speedy fix! ❤️