broken on Julia 1.6?

[tbenst]

See below for something that works on 1.5, but not 1.6. Seems related to display...

I'm using PyPlot v2.9.0 on Ubuntu (over ssh).

❯ julia
               _
   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.6.0 (2021-03-24)
 _/ |\__'_|_|_|\__'_|  |  Official https://julialang.org/ release
|__/                   |

julia> using PyPlot
plt = 
julia> plt = PyPlot
PyPlot

julia> global fig, axes = plt.subplots(2,1)
ERROR: (in a Julia function called from Python)
JULIA: UndefVarError: _apply_latest not defined
Stacktrace:
  [1] getproperty
    @ ./Base.jl:26 [inlined]
  [2] _pyjlwrap_call(f::Function, args_::Ptr{PyCall.PyObject_struct}, kw_::Ptr{PyCall.PyObject_struct})
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/callback.jl:37
  [3] pyjlwrap_call(self_::Ptr{PyCall.PyObject_struct}, args_::Ptr{PyCall.PyObject_struct}, kw_::Ptr{PyCall.PyObject_struct})
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/callback.jl:49
  [4] macro expansion
    @ ~/.julia/packages/PyCall/BcTLp/src/exception.jl:95 [inlined]
  [5] #110
    @ ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:43 [inlined]
  [6] disable_sigint
    @ ./c.jl:458 [inlined]
  [7] __pycall!
    @ ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:42 [inlined]
  [8] _pycall!(ret::PyCall.PyObject, o::PyCall.PyObject, args::Tuple{Int64, Int64}, nargs::Int64, kw::Ptr{Nothing})
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:29
  [9] _pycall!(ret::PyCall.PyObject, o::PyCall.PyObject, args::Tuple{Int64, Int64}, kwargs::Base.Iterators.Pairs{Union{}, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:11
 [10] pycall(::PyCall.PyObject, ::Type{PyCall.PyAny}, ::Int64, ::Vararg{Int64, N} where N; kwargs::Base.Iterators.Pairs{Union{}, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:83
 [11] pycall(::PyCall.PyObject, ::Type{PyCall.PyAny}, ::Int64, ::Vararg{Int64, N} where N)
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:83
 [12] subplots(::Int64, ::Vararg{Int64, N} where N; kws::Base.Iterators.Pairs{Union{}, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
    @ PyPlot ~/.julia/packages/PyPlot/XHEG0/src/PyPlot.jl:177
 [13] subplots(::Int64, ::Vararg{Int64, N} where N)
    @ PyPlot ~/.julia/packages/PyPlot/XHEG0/src/PyPlot.jl:174
 [14] top-level scope
    @ REPL[2]:1
 [15] eval
    @ ./boot.jl:360 [inlined]
 [16] eval_user_input(ast::Any, backend::REPL.REPLBackend)
    @ REPL /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.6/REPL/src/REPL.jl:139
 [17] repl_backend_loop(backend::REPL.REPLBackend)
    @ REPL /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.6/REPL/src/REPL.jl:200
 [18] start_repl_backend(backend::REPL.REPLBackend, consumer::Any)
    @ REPL /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.6/REPL/src/REPL.jl:185
 [19] run_repl(repl::REPL.AbstractREPL, consumer::Any; backend_on_current_task::Bool)
    @ REPL /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.6/REPL/src/REPL.jl:317
 [20] run_repl(repl::REPL.AbstractREPL, consumer::Any)
    @ REPL /buildworker/worker/package_linux64/build/usr/share/julia/stdlib/v1.6/REPL/src/REPL.jl:305
 [21] (::Base.var"#874#876"{Bool, Bool, Bool})(REPL::Module)
    @ Base ./client.jl:387
 [22] #invokelatest#2
    @ ./essentials.jl:708 [inlined]
 [23] invokelatest
    @ ./essentials.jl:706 [inlined]
 [24] run_main_repl(interactive::Bool, quiet::Bool, banner::Bool, history_file::Bool, color_set::Bool)
    @ Base ./client.jl:372
 [25] exec_options(opts::Base.JLOptions)
    @ Base ./client.jl:302
 [26] _start()
    @ Base ./client.jl:485
Stacktrace:
  [1] pyerr_check
    @ ~/.julia/packages/PyCall/BcTLp/src/exception.jl:62 [inlined]
  [2] pyerr_check
    @ ~/.julia/packages/PyCall/BcTLp/src/exception.jl:66 [inlined]
  [3] _handle_error(msg::String)
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/exception.jl:83
  [4] macro expansion
    @ ~/.julia/packages/PyCall/BcTLp/src/exception.jl:97 [inlined]
  [5] #110
    @ ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:43 [inlined]
  [6] disable_sigint
    @ ./c.jl:458 [inlined]
  [7] __pycall!
    @ ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:42 [inlined]
  [8] _pycall!(ret::PyCall.PyObject, o::PyCall.PyObject, args::Tuple{Int64, Int64}, nargs::Int64, kw::Ptr{Nothing})
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:29
  [9] _pycall!(ret::PyCall.PyObject, o::PyCall.PyObject, args::Tuple{Int64, Int64}, kwargs::Base.Iterators.Pairs{Union{}, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:11
 [10] pycall(::PyCall.PyObject, ::Type{PyCall.PyAny}, ::Int64, ::Vararg{Int64, N} where N; kwargs::Base.Iterators.Pairs{Union{}, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:83
 [11] pycall(::PyCall.PyObject, ::Type{PyCall.PyAny}, ::Int64, ::Vararg{Int64, N} where N)
    @ PyCall ~/.julia/packages/PyCall/BcTLp/src/pyfncall.jl:83
 [12] subplots(::Int64, ::Vararg{Int64, N} where N; kws::Base.Iterators.Pairs{Union{}, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
    @ PyPlot ~/.julia/packages/PyPlot/XHEG0/src/PyPlot.jl:177
 [13] subplots(::Int64, ::Vararg{Int64, N} where N)
    @ PyPlot ~/.julia/packages/PyPlot/XHEG0/src/PyPlot.jl:174
 [14] top-level scope
    @ REPL[2]:1

julia> 

❯ /opt/julia/julia-1.5.3/bin/julia
               _
   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.5.3 (2020-11-09)
 _/ |\__'_|_|_|\__'_|  |  Official https://julialang.org/ release
|__/                   |

julia> using PyPlot

julia> plt = PyPlot
PyPlot

julia> global fig, axes = plt.subplots(2,1)
(Figure(PyObject <Figure size 1280x960 with 2 Axes>), PyCall.PyObject[PyObject <AxesSubplot:>, PyObject <AxesSubplot:>])

julia>

[tbenst]

Just wanted to confirm that I get the same error locally for PyPlot on Julia 1.6, so it seems unfortunately that this package is currently broken.

[mzaffalon]

Can you provide a minimal working example?

[tbenst]

Hi @mzaffalon, yes I did in the original post. Here it is again for convenience:

using PyPlot
plt = PyPlot
fig, axes = plt.subplots(2,1)

Edit: or I suppose even more minimally: using PyPlot; PyPlot.subplots()

[mzaffalon]

Sorry, I misread the error message. It works fine for me:

> julia
               _
   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.6.0 (2021-03-24)
 _/ |\__'_|_|_|\__'_|  |  Official https://julialang.org/ release
|__/                   |

julia> using PyPlot

julia> fig, axes = plt.subplots(2,1)
(Figure(PyObject <Figure size 640x478 with 2 Axes>), PyCall.PyObject[PyObject <matplotlib.axes._subplots.AxesSubplot object at 0x0000000060D98C50>, PyObject <matplotlib.axes._subplots.AxesSubplot object at 0x0000000001C9F2B0>])

Any reason to call plt = PyPlot? Also the global keyword is not necessary.

[tbenst]

Hm, it worked for me too in a fresh environment.

But I could reproduce by doing the following:

> conda create -n jl-1.6 python=3.9
> julia
julia> ENV["CONDA_JL_HOME"] = "/home/tyler/opt/anaconda3/envs/jl-1.6"
pkg> build Conda
pkg> build PyPlot
julia> using PyPlot
julia> PyPlot.subplots()

This fails in julia 1.6, but works with julia 1.5

Edit: oh and global was vestige of the code where I discovered the problem, and plt naming is idiomatic python. Also note that other PyCall functionality still works fine, eg

math = pyimport("math")
math.sin(math.pi / 4)

[tbenst]

This is caused by JuliaPy/PyCall.jl#873. Updating PyCall to v1.92.2 resolved the issue!