unquote piped into unquote results in invalid unquote/2 invocation

[elliottneilclark]

Versions

• Elixir: Elixir 1.14.5 (compiled with Erlang/OTP 25)
• Styler: locked at 0.7.12 (styler) 9b309b7c

Example Input

  defp pipe(left, right) do
    quote do
      unquote(left) |> unquote(right)
    end
  end

Stacktrace / Current Behaviour

That produces:

  defp pipe(left, right) do
    quote do
      unquote(unquote(left), right)
    end
  end

[novaugust]

Heya, thanks for the issue.

This doesn't look like something we'll fix in Styler. Sometimes when it makes kaboomy code, it's a good chance to zoom out and see if things can just be written different -- kind of like when the formatter makes code look weird.

In this case, I'd suggest using bind_quoted to remove the use of unquote. At that point, Styler would rewrite left |> right as just right(left), and your code will be just that little bit happier.

[elliottneilclark]

In this case, I'd suggest using bind_quoted to remove the use of unquote.

That's not possible in the place that I extracted the code from, but I understand your point of there are other ways to write this. (this is from code generation path that produces code from a Macro.to_string and the final format is more important so it's unsual) I still think this is worth solving by ignoring code in quote.

From experience with black/clang-format on large code bases I can tell you that you need to either focus on never producing broken code, or allow configuring styler in specific cases. #noqa or the like. The project README shows this already becoming apparent. There are a number of gotchas around styler making incorrect changes. You can't turn those checks off like you can with credo, and you have to manually fix them.

TLDR: You should follow Linus' golden rule:

You Do Not Break Userspace

[novaugust]

thanks for the input elliott, but having styler style code inside of quote is quite intentional - we like to keep all our code consistent. that said, we're very supportive of people forking the library and making the tool their own.

[novaugust]

while we don't want to disable styler in quotes, making it work with the idea that some unquote usages only work with a preceding pipe is good style, if you will. got it fixed on main, thanks

[elliottneilclark]

having styler style code inside of quote is quite intentional

Totally, that was simply the easiest tactical fix I could see, since creating quoted piped code wasn't that common. Thanks for the even better solution!