Gadfly embedded NULs and invalid plotting

[datadreamscorp]

Opened one of my scripts today to find this error whenever I tried to plot using a DataFrame in Pluto.jl. Tried plotting to vectors in another session and axis ticks are not showing properly (image below), which I guess is part of the problem.

Failed to show value:

ArgumentError: embedded NULs are not allowed in C strings: "-\0.\0"

[email protected]:216[inlined]
pango_to_svg(::String)@pango.jl:330
draw(::Compose.SVG, ::Compose.TextPrimitive{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}, Compose.Rotation{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}}, Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}}, ::Int64)@svg.jl:975
draw(::Compose.SVG, ::Compose.Form{Compose.TextPrimitive{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}, Compose.Rotation{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}}, Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}}})@svg.jl:732
drawpart(::Compose.SVG, ::Compose.Context, ::Compose.IdentityTransform, ::Compose.UnitBox{Float64, Float64, Float64, Float64}, ::Measures.BoundingBox{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}, Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}})@container.jl:477
drawpart(::Compose.SVG, ::Compose.Context, ::Compose.IdentityTransform, ::Compose.UnitBox{Float64, Float64, Float64, Float64}, ::Measures.BoundingBox{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}, Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}})@container.jl:509
drawpart(::Compose.SVG, ::Compose.AdhocContainerPromise, ::Compose.IdentityTransform, ::Compose.UnitBox{Float64, Float64, Float64, Float64}, ::Measures.BoundingBox{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}, Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}})@container.jl:390
drawpart(::Compose.SVG, ::Compose.Context, ::Compose.IdentityTransform, ::Compose.UnitBox{Float64, Float64, Float64, Float64}, ::Measures.BoundingBox{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}, Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}})@container.jl:509
drawpart(::Compose.SVG, ::Compose.Table, ::Compose.IdentityTransform, ::Compose.UnitBox{Float64, Float64, Float64, Float64}, ::Measures.BoundingBox{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}, Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}})@container.jl:390
drawpart(::Compose.SVG, ::Compose.Context, ::Compose.IdentityTransform, ::Compose.UnitBox{Float64, Float64, Float64, Float64}, ::Measures.BoundingBox{Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}, Tuple{Measures.AbsoluteLength, Measures.AbsoluteLength}})@container.jl:509
[email protected]:356[inlined]
show(::IOContext{IOBuffer}, ::MIME{Symbol("text/html")}, ::Compose.Context)@Compose.jl:182
show_richest(::IOContext{IOBuffer}, ::Any)@PlutoRunner.jl:640
var"#sprint_withreturned#28"(::IOContext{Base.DevNull}, ::Int64, ::typeof(Main.PlutoRunner.sprint_withreturned), ::Function, ::Compose.Context)@PlutoRunner.jl:579
format_output_default(::Any, ::Any)@PlutoRunner.jl:503
#format_output#[email protected]:520[inlined]
formatted_result_of(::Base.UUID, ::Bool, ::Nothing)@PlutoRunner.jl:435
top-level scope@none:1

[datadreamscorp]

Happening in REPL as well.

[pdeffebach]

I can reproduce on Mac with 1.6.0. Not the error, but the unicode errors in the axes.

[rikhuijzer]

It also occurs for me on NixOS with a fresh Julia after updating my dependencies. I'll see whether I can find the upstream culprit.

[Mattriks]

There's a discourse thread too

[rikhuijzer]

When looking at the dependencies, I would expect it to be Colors.jl since it got updated two days ago. Unfortunately, pinning that to 0.12.6 as used here doesn't seem to be helping.

[rikhuijzer]

I've got the first Gadfly error on 2021-04-28 around 15:00 GMT. When looking through the General registry for changes, there recently have been updates to:

• Colors.jl
• ColorTypes.jl
• StaticArrays.jl

I've pinned them all to older versions with a Gadfly dev project, but plots keep failing. I guess that to fix this, it is necessary to approach the problem from another direction, namely debugging the code.

[rikhuijzer]

I'm pretty sure that Showoff.jl is the culprit. On Julia 1.6.1 in my normal environment:

julia> using Showoff

julia> showoff([100.0], :auto)
1-element Vector{String}:
 "\x0000"

and on Julia 1.5, Julia 1.6.0 and Julia 1.6.1 via Docker with Showoff v.1.0.2.

julia> showoff([100.0], :auto)
1-element Array{String,1}:
 "100"

[rikhuijzer]

@datadreamscorp The issue should be solved by https://discourse.julialang.org/t/plotting-broken-gadfly-and-plots-backends-not-showing-axis-ticks-cant-plot-dataframes/60201/10. Can you close this issue or do you still have problems?