isdeprecated should not resolve binding

[pfitzseb]

This is one way to fix https://discourse.julialang.org/t/inconsistent-base-method-overwrite-behaviour/15367 and related issues. Without this PR the following rather undesirable things happen:

λ j1 --quiet
julia> sin<tab>
sin    sinc    sincos  sind    sinh    sinpi
julia> sin=2
ERROR: cannot assign variable Base.sin from module Main
Stacktrace:
 [1] top-level scope at none:0

julia on sp/isdepnoresolve 
λ j1 --quiet
julia> Base.isdeprecated(Main, :sin); sin = 3
ERROR: cannot assign variable Base.sin from module Main
Stacktrace:
 [1] top-level scope at none:0

I think this behaviour is more sensible than making sure to write

isbindingesolved(mod, sym) && isdeprecated(mod, sym)

to avoid accidentally resolving bindings.

[StefanKarpinski]

Looks good to me but @JeffBezanson should really take a quick look.

[JeffBezanson]

Yes, I think this is ok, as long as uses of isdeprecated call it on the module exporting the binding in question rather than on possible client modules. All uses in base and stdlib seem to conform to that.

[JeffBezanson]

Please see other if statements in this file for the style we use.

[JeffBezanson]

I recommend making an empty module for this purpose so it doesn't depend on Main, which will be unpredictable.

[pfitzseb]

Thanks for the comments, should be addressed now :)

Yes, I think this is ok, as long as uses of isdeprecated call it on the module exporting the binding in question rather than on possible client modules. All uses in base and stdlib seem to conform to that.

Well, this for example will call isdeprecated on Main instead of e.g. Base all the time, which is why it's important that isdeprecated doesn't resolve the binding.

[JeffBezanson]

Well, this for example will call isdeprecated on Main instead of e.g. Base all the time

That's true, but as of now that code is almost a bug --- there should never be a need to call isdeprecated(Main, ...) because Main itself never deprecates anything. Of course if the REPL were attached to a different module the code might make sense.

[JeffBezanson]

Failures are #29923