Save-only error on newly registered file type with custom package

[BambOoxX]

@maucejo 's https://github.com/maucejo/UFFFiles.jl was recently merged into the FileIO registry.
For my work, I have a custom package that handles similar files.

To handle the load / save logic, so far, I used the following in my package.

function load(f::File{format"UNV"})
    ...
end

function save(f::File{format"UNV"}, data)
    ...
end

detect_unv(io) = endswith(io.name, ".unv>") || endswith(io.name, ".uff>")

function __init__()
    add_format(format"UNV", detect_unv, [".unv", ".uff"], [MyPackage])
end

Since 1.18, which is the introduction of UFFFiles in the registry, my tests fail for save, but load works fine.

ERROR: ArgumentError: Package UFFFiles [20c5726e-8372-4c34-be2c-190a5a70d483] is required but does not seem to be installed

I could have expected that both success (as in previous FileIO versions) or fail, but I don't understand a partial fail.

Any ideas what could be the reason ?

I've attempted to make a MWE, but in a module, not totally a package, so the init-equivalent step may not be relevant as such.

using Pkg
Pkg.activate("TestFileIO")
Pkg.add(name="FileIO", version="1.17")

unvname = joinpath(tempdir(), "test.unv")
write(unvname, "test")

module TempFileIO
using FileIO

function load(f::File{FileIO.format"UNV"})
    open(f, "r") do s
        String(take!(s.io))
    end
end

function save(f::File{FileIO.format"UNV"}, data)
    open(f, "w") do s
        write(s.io, data)
    end
end

detect_unv(io) = endswith(io.name, ".unv>") || endswith(io.name, ".uff>")

add_loader(format"UNV", detect_unv, [".unv", ".uff"], [TempFileIO])
end

using .TempFileIO

using FileIO

load(unvname) # Works regardless of version
save(unvname, "test") # Fails in 1.18+ since UFF is registered

[maucejo]

Hi @BambOoxX. I am usure about the roots of this partial fail. What I can tellement you is that the changes I made to FileIO are minor and follow the guidelines. From the UFFFiles side, I have implemented the save\load logic using these lines:

fileio_load(file::File{FileIO.format"UFF"}) = readuff(file.filename)
fileio_save(file::File{format"UFF"}, data) = writeuff(file.filename, data)

I observe that in the save function I have format"UFF" instead of FileIO.format"UFF". I think that it is the root of your problem.

I will fix that on Friday.

Could you tell me if this change fix your issue?