Support interpolating in git cmd string macro

[DilumAluthge]

I think this is a bug in Julia?

julia> macro foo_cmd(ex)
       println(ex)
       end
@foo_cmd (macro with 1 method)

julia> a = "123"
"123"

julia> foo`x y z`
x y z

julia> foo`x $a z`
x $a z

[DilumAluthge]

julia> macro foo_str(ex)
       println(ex)
       end
@foo_str (macro with 1 method)

julia> macro bar_cmd(ex)
       println(ex)
       end
@bar_cmd (macro with 1 method)

julia> a = "hello"
"hello"

julia> foo"$a"
$a

julia> bar`$a`
$a

[DilumAluthge]

https://github.com/JuliaLang/julia/issues/23481

[DilumAluthge]

The discussion in https://github.com/JuliaLang/julia/issues/23481 seems to imply that support for interpolation string macros won’t be added to Julia.

So we’d have to add the support ourselves in this package.

[fredrikekre]

So we’d have to add the support ourselves in this package.

Yea, thats what I meant from the start, should have been more clear.

[DilumAluthge]

So we’d have to add the support ourselves in this package.

Yea, thats what I meant from the start, should have been more clear.

Nah, the confusion was all on me.

Anyway, sounds like a good idea. I don’t really know enough about macros to figure out how to don’t this; maybe someone else can help out.

[fredrikekre]

I haven't looked at it, but can maybe look at what @btime etc does since they also use $ in macros to men interpolation (although for a different purpose).

[omus]

I had to deal with handling interpolation in a non-standard string literal here: https://github.com/invenia/MultilineStrings.jl/blob/3192dbf8872b99cb2a09a46894b22428191805ca/src/MultilineStrings.jl#L120. I think the same approach would probably work here

[GunnarFarneback]

I propose to deprecate the cmd string macro in favor of git("clone https://github.com/JuliaRegistries/General") and split the argument with Base.shell_split. This gives interpolation for free and allows the use of whatever string macros people want to use. (I already have a PR in preparation for git(::AbstractString)).

[fredrikekre]

Isn't it better to just let people use

git = Git.git()
`$git clone ....`

?

[GunnarFarneback]

That's already available so if we think that's all that's needed the easiest solution is just to remove the cmd macro.

[fredrikekre]

Exactly. Is there any other advantage with the cmd macro?

[GunnarFarneback]

Considering that it currently does a plain split of the argument I would say that it's mostly kinda dangerous but for one time uses it's a bit more compact than first having to create the git object or interpolating it into the command. ~My proposal would allow things like git(raw"status src\foo\bar.jl") which might be practical if you e.g. need to copy/paste paths on Windows.~ Never mind, shell_split destroys the backslashes.

The functionality I really want, however, is git(["status", "README.md"]) to bypass the cmd argument parsing. But maybe the magic of the cmd interpolation of iterables doesn't make it worth the trouble.

[DilumAluthge]

It sounds like the plan here would be:

1. Remove the @git_cmd cmd macro. We can do this in a nonbreaking release because it's not part of the public API.
2. Add a new method git(::AbstractVector(<:AbstractString)) for the use case that @GunnarFarneback wants.

[DilumAluthge]

Step 1 is done in #34