[Libguestfs] [nbdkit PATCH 2/2] plugins/rust: restrict predicates-{tree, core} to {1.0.7, 1.0.5}

[Eric Blake]

On Tue, Mar 28, 2023 at 06:25:14PM +0200, Laszlo Ersek wrote:
> The beautiful world of uncontained dependencies:
> 
> - We restrict mockall to 0.11.0, which in practice currently expands to
>   0.11.4,
> 
> - mockall depends on predicates-tree,
> 
> - predicates-tree depends on predicates-core,
> 
> - approx. two weeks ago, predicates-tree and predicates-core have seen
>   *PATCHLEVEL* upgrades (1.0.7 -> 1.0.9, and 1.0.5 -> 1.0.6, respectively)
>   that now require "rustc 1.64.0 or newer".
> 
> RHEL-9.2 will eventually ship rustc 1.66, but RHEL-9.2 has not been
> released. The above rustc requirement bump breaks the nbdkit build on
> RHEL-9.1 -- which provides rustc 1.62. Restrict predicates-{tree,core} to
> {1.0.7,1.0.5}.
> 
> (Side commentary: when such things can happen via a *patchlevel* upgrade,
> that makes a total mockery of "semantic versioning"
> <https://en.wikipedia.org/wiki/Software_versioning#Semantic_versioning>.)

Yeah, I get the feeling that the Rust community has not yet learned
the hard lessons that it has taken the C community years to
understand.  Versioning is hard, but being cavalier about it is not
doing your users a service.

> 
> Signed-off-by: Laszlo Ersek <lersek at redhat.com>
> ---
>  plugins/rust/Cargo.toml | 2 ++
>  1 file changed, 2 insertions(+)

I'm not a Rust expert, so I won't give R-b, but since it fixes the
build, I can at least offer:

Acked-by: Eric Blake <eblake at redhat.com>

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
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