`redirect_stdin` with temp file fails inside compile workload

[sandyspiers]

Hi,

Testing functionality that requires stdin is usually done using a temporary file and redirect_stdin.

Or at least, this is how this is tested in julia, using something like

julia> let filename = tempname()
           open(filename, "w") do io
               print(io, "hello")
           end

           ret = open(filename) do f
               redirect_stdin(f) do
                   readline()
               end
           end

           @info ret
       end
[ Info: hello

But this same code fails inside a @compile_workload,

module PrecompileStdin

using PrecompileTools

@setup_workload begin
    @compile_workload begin
        let filename = tempname()
            open(filename, "w") do io
                print(io, "hello")
            end

            ret = open(filename) do f
                redirect_stdin(f) do
                    readline()
                end
            end

            @info ret
        end
    end
end

end

(PrecompileStdin) pkg> precompile
  ✗ PrecompileStdin
Precompiling packages finished.
  0 dependencies successfully precompiled in 2 seconds. 6 already precompiled.

ERROR: The following 1 direct dependency failed to precompile:

PrecompileStdin

Failed to precompile PrecompileStdin [8f563060-54df-4cc8-b9ee-fdd41108d2e7] to "/home/sandy/.julia/compiled/v1.12/PrecompileStdin/jl_S7650f".
ERROR: LoadError: SystemError: dup: Bad file descriptor
Stacktrace:
  [1] systemerror(p::String, errno::Int32; extrainfo::Nothing)
    @ Base ./error.jl:186
  [2] systemerror
    @ ./error.jl:185 [inlined]
  [3] dup
    @ ./libc.jl:47 [inlined]
  [4] _redirect_io_libc
    @ ./stream.jl:1252 [inlined]
  [5] (::Base.RedirectStdStream)(handle::Base.PipeEndpoint)
    @ Base ./stream.jl:1262
  [6] (::Base.RedirectStdStream)(thunk::PrecompileStdin.var"#8#9", stream::IOStream)
    @ Base ./stream.jl:1466
  [7] #6
    @ ~/docs/quicks/PrecompileStdin/src/PrecompileStdin.jl:13 [inlined]
  [8] open(f::PrecompileStdin.var"#6#7", args::String; kwargs::@Kwargs{})
    @ Base ./io.jl:410
  [9] open(f::Function, args::String)
    @ Base ./io.jl:407
 [10] macro expansion
    @ ~/docs/quicks/PrecompileStdin/src/PrecompileStdin.jl:12 [inlined]
 [11] macro expansion
    @ ~/.julia/packages/PrecompileTools/gn08A/src/workloads.jl:73 [inlined]
 [12] macro expansion
    @ ~/docs/quicks/PrecompileStdin/src/PrecompileStdin.jl:6 [inlined]
 [13] macro expansion
    @ ~/.julia/packages/PrecompileTools/gn08A/src/workloads.jl:121 [inlined]
 [14] top-level scope
    @ ~/docs/quicks/PrecompileStdin/src/PrecompileStdin.jl:5
 [15] include(mod::Module, _path::String)
    @ Base ./Base.jl:306
 [16] include_package_for_output(pkg::Base.PkgId, input::String, depot_path::Vector{String}, dl_load_path::Vector{String}, load_path::Vector{String}, concrete_deps::Vector{Pair{Base.PkgId, UInt128}}, source::Nothing)
    @ Base ./loading.jl:3024
 [17] top-level scope
    @ stdin:5
 [18] eval(m::Module, e::Any)
    @ Core ./boot.jl:489
 [19] include_string(mapexpr::typeof(identity), mod::Module, code::String, filename::String)
    @ Base ./loading.jl:2870
 [20] include_string
    @ ./loading.jl:2880 [inlined]
 [21] exec_options(opts::Base.JLOptions)
    @ Base ./client.jl:315
 [22] _start()
    @ Base ./client.jl:550
in expression starting at /home/sandy/docs/quicks/PrecompileStdin/src/PrecompileStdin.jl:1
in expression starting at stdin:

I am not sure if this is intended or a bug.

Thanks in advance :)

[sandyspiers]

It is possible to work around this with a try/catch, since it seems the error occurs when exiting the redirect_stdin(f) block.