D1581: rust: implementation of `hg`

[yuja (Yuya Nishihara)]

yuja added inline comments.

INLINE COMMENTS

> indygreg wrote in Cargo.lock:1
> According to https://doc.rust-lang.org/cargo/faq.html#why-do-binaries-have-cargolock-in-version-control-but-not-libraries (and other places I found on the Internet), `Cargo.lock` files under version control are a good practice for binaries - but not libraries.
> 
> Since this `Cargo.lock` encompasses the `hgcli` binary, I think that counts.
> 
> FWIW, Firefox vendors `Cargo.lock` files for libraries. Although those libraries are attached to C++ binaries, so there isn't an appropriate Rust binary to attach to. But a main purpose of `Cargo.lock` files is to add determinism. For that reason, I think we want them vendored.

> Cargo.lock files under version control are a good practice for binaries

Okay, I didn't know that, thanks. (FWIW, I don't like the idea of version-controlling
strict build dependencies, but let's just follow their rule.)

Can we move Cargo.lock under hgcli directory, then? Sounds like we'll need a
separate Cargo.lock file for "libraries".

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D1581

To: indygreg, #hg-reviewers, yuja
Cc: yuja, quark, durin42, dlax, mercurial-devel