[BUG] Heatmap with DateTime x-axis causes error

[hagi123456]

Details

I want to create a heatmap with DateTime axis as for example shown in the Plots documentation:

using Plots
plotlyjs()
using Dates
heatmap(DateTime.(2016:2020), 1:5, rand(5, 5))

Unfortunately, this causes an error.

Error showing value of type Plots.Plot{Plots.PlotlyJSBackend}:
ERROR: MethodError: no method matching -(::String, ::String)
Stacktrace:
  [1] __heatmap_edges(v::Vector{String}, isedges::Bool, ispolar::Bool)
    @ Plots ~/.julia/packages/Plots/HyyIK/src/utils.jl:244
  [2] _heatmap_edges(::Val{true}, v::Vector{String}, ::Symbol, isedges::Bool, ispolar::Bool)
    @ Plots ~/.julia/packages/Plots/HyyIK/src/utils.jl:249
  [3] heatmap_edges(v::Vector{String}, scale::Symbol, isedges::Bool, ispolar::Bool)
    @ Plots ~/.julia/packages/Plots/HyyIK/src/utils.jl:258
  [4] plotly_series(plt::Plots.Plot{Plots.PlotlyJSBackend}, series::Plots.Series)
    @ Plots ~/.julia/packages/Plots/HyyIK/src/backends/plotly.jl:596
  [5] #653
    @ ./none:0 [inlined]
  [6] MappingRF
    @ ./reduce.jl:100 [inlined]
  [7] _foldl_impl(op::Base.MappingRF{Plots.var"#653#654"{…}, Base.BottomRF{…}}, init::Base._InitialValue, itr::Vector{Plots.Series})
    @ Base ./reduce.jl:58
  [8] foldl_impl
    @ ./reduce.jl:48 [inlined]
  [9] mapfoldl_impl
    @ ./reduce.jl:44 [inlined]
 [10] mapfoldl
    @ ./reduce.jl:175 [inlined]
 [11] mapreduce
    @ ./reduce.jl:307 [inlined]
 [12] reduce
    @ ./reduce.jl:490 [inlined]
 [13] plotly_series
    @ ~/.julia/packages/Plots/HyyIK/src/backends/plotly.jl:1045 [inlined]
 [14] plotlyjs_syncplot(plt::Plots.Plot{Plots.PlotlyJSBackend})
    @ Plots ~/.julia/packages/Plots/HyyIK/src/backends/plotlyjs.jl:10
 [15] _display(plt::Plots.Plot{Plots.PlotlyJSBackend})
    @ Plots ~/.julia/packages/Plots/HyyIK/src/backends/plotlyjs.jl:44
 [16] display(::Plots.PlotsDisplay, plt::Plots.Plot{Plots.PlotlyJSBackend})
    @ Plots ~/.julia/packages/Plots/HyyIK/src/output.jl:169
 [17] display(x::Any)
    @ Base.Multimedia ./multimedia.jl:340
 [18] #invokelatest#2
    @ Base ./essentials.jl:887 [inlined]
 [19] invokelatest
    @ Base ./essentials.jl:884 [inlined]
 [20] print_response(errio::IO, response::Any, show_value::Bool, have_color::Bool, specialdisplay::Union{Nothing, AbstractDisplay})
    @ REPL /opt/julia/julia-1.10.0/share/julia/stdlib/v1.10/REPL/src/REPL.jl:315
 [21] (::REPL.var"#57#58"{REPL.LineEditREPL, Pair{Any, Bool}, Bool, Bool})(io::Any)
    @ REPL /opt/julia/julia-1.10.0/share/julia/stdlib/v1.10/REPL/src/REPL.jl:284
 [22] with_repl_linfo(f::Any, repl::REPL.LineEditREPL)
    @ REPL /opt/julia/julia-1.10.0/share/julia/stdlib/v1.10/REPL/src/REPL.jl:569
 [23] print_response(repl::REPL.AbstractREPL, response::Any, show_value::Bool, have_color::Bool)
    @ REPL /opt/julia/julia-1.10.0/share/julia/stdlib/v1.10/REPL/src/REPL.jl:282
 [24] (::REPL.var"#do_respond#80"{…})(s::REPL.LineEdit.MIState, buf::Any, ok::Bool)
    @ REPL /opt/julia/julia-1.10.0/share/julia/stdlib/v1.10/REPL/src/REPL.jl:911
 [25] #invokelatest#2
    @ Base ./essentials.jl:887 [inlined]
 [26] invokelatest
    @ Base ./essentials.jl:884 [inlined]
 [27] run_interface(terminal::REPL.Terminals.TextTerminal, m::REPL.LineEdit.ModalInterface, s::REPL.LineEdit.MIState)
    @ REPL.LineEdit /opt/julia/julia-1.10.0/share/julia/stdlib/v1.10/REPL/src/LineEdit.jl:2656
 [28] run_frontend(repl::REPL.LineEditREPL, backend::REPL.REPLBackendRef)
    @ REPL /opt/julia/julia-1.10.0/share/julia/stdlib/v1.10/REPL/src/REPL.jl:1312
 [29] (::REPL.var"#62#68"{REPL.LineEditREPL, REPL.REPLBackendRef})()
    @ REPL /opt/julia/julia-1.10.0/share/julia/stdlib/v1.10/REPL/src/REPL.jl:386
Some type information was truncated. Use `show(err)` to see complete types.

Backends

This bug occurs on ( insert x below )

Backend	yes	no	untested
gr (default)		x
pythonplot			x
plotlyjs	x
pgfplotsx		x	though the xticks are wrong; could be just unix epochs
unicodeplots			x
inspectdr			x
gaston			x

Versions

Plots.jl version: v1.40.1
Backend version:

• Plotly v0.4.1
• PlotlyJS v0.18.13
  Output of versioninfo():

Julia Version 1.10.0
Commit 3120989f39b (2023-12-25 18:01 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 12 × AMD Ryzen 5 3600 6-Core Processor
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-15.0.7 (ORCJIT, znver2)
  Threads: 17 on 12 virtual cores