remove some unncessary and/or misleading methods of copy

[JeffBezanson]

I think it's better not to define copy on objects where it doesn't make sense and doesn't do anything. IIRC, most of these definitions were introduced a long time ago when they might have been needed for copying ASTs. That was silly, and has been replaced by the internal astcopy function that knows how to copy only what's needed.

These can cause problems, such as writing copy(str).data and thinking you'll get a new copy of the string's data.

To minimize breakage, I'm leaving the definitions for Range and Number for now, since there is some code that assumes all array-like things are copyable.

[tkelman]

@jrevels how far are we from hooking up automatic pkgeval on demand?

[jrevels]

how far are we from hooking up automatic pkgeval on demand?

It's not something I've worked on, besides separating out the CI bot code from the benchmarking code. After this week, my paper-crunch should be over, and I'll finally have time to finish the current iteration of our benchmark tools. After that, I'll be working on the CI stuff again. I was going to start with setting up a database for the benchmark data, but it seems like getting the CI bot to run pkgeval is more urgent, so I could refocus and prioritize that instead.

[tkelman]

Good to know, thanks. PkgEval can be run manually anywhere we think we need it for now, and abusing git instead of using a real database has worked for the pkg.julialang.org results for a while. Either would be useful.

[timholy]

This should have had some kind of deprecation warning, rather than just removing the methods.

JuliaImages/Images.jl#478.

[timholy]

Also needs fixing:

julia/base/fft/FFTW.jl

Line 462 in a64c24a

R = copy(region)

(perhaps among others)

[JeffBezanson]

@timholy What was being copied in Images?

[timholy]

A string, https://github.com/timholy/Images.jl/blob/531bd0131079dd59db44ffdf8caeede81e7fd291/src/core.jl#L156-L160.

If you want to trigger the second error, you should be able to just replace dictcopy with deepcopy (now that it's type-stable) and then run the Images tests.