New formatting turns optional positional argument into keyword argument

[gdalle]

Kudos on the full rewrite!
Unfortunately I have encountered a bug when I tried to apply the new formatting in JuliaDiff/DifferentiationInterface.jl#589. An unnamed, Val-typed positional argument was "formatted" into a keyword argument (see this comment).

Schematically, the following code

function f(x, y, ::Val{N}=Val(1)) where {N}

turned into (note the semicolon)

function f(x, y; (::Val{N})=Val(1)) where {N}

which changed the semantics.

EDIT: As discussed below, this apparently applied to all optional positional arguments, named or not. It might be due to BlueStyle.

[MilesCranmer]

Same bug unfortunately. All optional arguments (named or not) seem to get converted to keyword arguments.

@domluna do you think you could yank versions 2.0.0 and 1.0.62 until these bugs and #879 are patched? (I am unfortunately needing to patch all my CI scripts at the moment).

Thanks for all your hard work!!

[domluna]

@domluna do you think you could yank versions 2.0.0 and 1.0.62 until these bugs and #879 are patched? (I am unfortunately needing to patch all my CI scripts at the moment).

what do I need to do to yank the release?

[avik-pal]

https://github.com/JuliaRegistries/General#when-is-yanking-a-release-appropriate open a PR with yanked=true

[domluna]

@MilesCranmer why does 1.0.62 need to be yanked?

[MilesCranmer]

The latest version of 1 seemed to change the rules in a breaking way, not sure the number

[domluna]

The latest version of 1 seemed to change the rules in a breaking way, not sure the number

there hasn't been any major changes for the past few releases, is there an example?

[gdalle]

Here's a minimum working example, where the first two formattings work and the last one introduces an unwanted kwarg:

julia> using JuliaFormatter  # version 2

julia> format_text("""
       function f(x::Vector{T}) where {T}
           return nothing
       end
       """, BlueStyle()) |> println
function f(x::Vector{T}) where {T}
    return nothing
end


julia> format_text("""
       function f(x::Vector=[])
           return nothing
       end
       """, BlueStyle()) |> println
function f(x::Vector=[])
    return nothing
end


julia> format_text("""
       function f(x::Vector{T}=[]) where {T}
           return nothing
       end
       """, BlueStyle()) |> println
function f(; x::Vector{T}=[]) where {T}
    return nothing
end

So it might be the combination of a parametric type and a default value that is to blame

[MilesCranmer]

@domluna I see, then that’s probably my mistake, and it’s only 2.0.0 that should be yanked.

(What I assume happened is I added 1.0.62 to my env, but 2.0.0 was already loaded somewhere from my base env, and that’s what actually did the formatting. I’ll double check this though.)