Safe figure saving by default, + new arg

[isentropic]

Like I suggested before in #3001

[isentropic]

julia> p = plot(rand(10), safe_saving=true);

julia> savefig(p, "this.png")
"/Users/z/Projects/Plots.jl/this.png"

julia> savefig(p, "this.png")
┌ Warning: Filename /Users/z/Projects/Plots.jl/this.png already exists, defaulting to prevent overriding. To disable this behavior, provide `:safe_saving=false` kwarg, i.e. `plot(rand(10), safe_saving=false)`
└ @ PlotsBase ~/Projects/Plots.jl/PlotsBase/src/output.jl:142

julia> p = plot(rand(10), safe_saving=false);

julia> savefig(p, "this.png")
"/Users/z/Projects/Plots.jl/this.png"

[isentropic]

I'll fix the tests, once we agree if it goes into 2.0 or not. I was also thinking instead of making this a property of a plot, maybe just make it a flag in savefig feature, but then maybe someone would want this unsafe behavior by default. Making it part of plot struct will enable such defaulting

[BeastyBlacksmith]

I'll fix the tests, once we agree if it goes into 2.0 or not. I was also thinking instead of making this a property of a plot, maybe just make it a flag in savefig feature, but then maybe someone would want this unsafe behavior by default.

I would be in favor of making it a part of savefig, same goes for tex_output_standalone. If changing the default is the main concern we could make it a ScopedValue

[isentropic]

I can't understand how scopedvalues can help here. Can you give an example please?

[BeastyBlacksmith]

julia> using ScopedValues

julia> const DEFAULT_OVERWRITE = ScopedValue(false)
ScopedValue{Bool}(0)

julia> savefig(;overwrite = DEFAULT_OVERWRITE) = @show overwrite[]
savefig (generic function with 1 method)

julia> savefig()
overwrite[] = false
false

julia> with(DEFAULT_OVERWRITE => true) do
         savefig()
       end
overwrite[] = true
true

[isentropic]

I see, I meant about script usage. Probably some people have their research pipelines such that there is some saving done inside. Like having users modify so much code to accomodate such a change might be too drastic

I was thinking that a user would set the flag in Prefernces.jl or startup.jl

Now that I'm looking into these, where are the docs about setting the defaults? I can't seem to find the docs about default setting anymore

[BeastyBlacksmith]

I think its the tip on the bottom of this page: https://docs.juliaplots.org/stable/install/

[isentropic]

So you still think ScopedValue is the right solution here?

[BeastyBlacksmith]

I do. I mean, you can still do something like

const DEFAULT_OVERWRITE = ScopedValue(get(PLOTS_DEFAULTS, :overwrite, false))

To get change it based on some value in startup.jl.