1.1.3 regression? "Unexpected 'CALL_END'" error on inline assignment expression

[aseemk]

Hey there,

This block of code used to work in 1.1.2 (I just confirmed by downgrading):

$actionButton.val label=
    if isFollow then 'Follow'
    else if isTouch then "✘ Unfollow #{NBSP}"
    else "✔ Following #{NBSP}"

The intent is that the if/else block's value should be assigned to the variable label, and then the val() method be called w/ that same value.

The generated JS in 1.1.2:

var label;
$actionButton.val(label = isFollow ? 'Follow' : isTouch ? "✘ Unfollow " + NBSP : "✔ Following " + NBSP);

In 1.1.3 (you can test via the website), the same block now throws this error:

PARSE ERROR ON LINE 1: UNEXPECTED 'CALL_END'

Is this an accidental regression, or a purposeful change? I'm guessing that with the bugfix version bump, it's an accidental regression.

Thanks!

/cc @jeremyis

[TrevorBurnham]

Confirmed. The key here is the line break in the function call with implicit parentheses. A simpler test case is

func x =
  y

Without the function call, it works. If you escape the line break, i.e.

func x = \
  y

then it works. If you use explicit parentheses, i.e.

func(x =
  y)

then it works.

Line breaks in function calls with implicit parentheses have always been a tricky case for the parser, so I'd highly recommend using explicit parentheses for cases like this one. Nonetheless, I doubt this was an intended change, so I'm labeling it as a bug. Bisecting...

[jashkenas]

Thanks for reporting this -- the above patch should fix it.

[jashkenas]

@TrevorBurnham For the record, there are a number of regressions for edge cases (untested) relating to satyr's change to the "unifinished" lexer logic. I'd like to keep his improvements in place, but make the rewriter aware that now some right-hand-sides will be indented, where previously the indentation was suppressed.

[aseemk]

Great. Thanks!

[TrevorBurnham]

Bisect tells me that the problem stems from 2ea51b0, so pinging @satyr.

[jashkenas]

Trevor: it's fixed.

[TrevorBurnham]

Ah, that'll teach me not to refresh before posting. Thanks, @jashkenas.