rust: switch hg-core and hg-cpython to rust 2018 edition
Many interesting changes have happened in Rust since the Oxidation Plan was
introduced, like the 2018 edition and procedural macros:
- Opting in to the 2018 edition is a clear benefit in terms of future
proofing, new (nice to have) syntactical sugar notwithstanding. It
also has a new non-lexical, non-AST based borrow checker that has
fewer bugs(!) and allows us to write correct code that in some cases
would have been rejected by the old one.
- Procedural macros allow us to use the PyO3 crate which maintainers have
expressed the clear goal of compiling on stable, which would help in
code maintainability compared to rust-cpython.
In this patch are the following changes:
- Removing most `extern crate` uses
- Updating `use` clauses (`crate` keyword, nested `use`)
- Removing `mod.rs` in favor of an aptly named module file
Like discussed in the mailing list (
https://www.mercurial-scm.org/pipermail/mercurial-devel/2019-July/132316.html
), until Rust integration in Mercurial is considered to be out of the
experimental phase, the maximum version of Rust allowed is whatever the latest
version Debian packages.
Differential Revision: https://phab.mercurial-scm.org/D6597
#require no-reposimplestore
$ . "$TESTDIR/narrow-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [narrow]
> serveellipses=True
> EOF
$ for x in `$TESTDIR/seq.py 10`
> do
> echo $x > "f$x"
> hg add "f$x"
> done
$ hg commit -m "Add root files"
$ mkdir d1 d2
$ for x in `$TESTDIR/seq.py 10`
> do
> echo d1/$x > "d1/f$x"
> hg add "d1/f$x"
> echo d2/$x > "d2/f$x"
> hg add "d2/f$x"
> done
$ hg commit -m "Add d1 and d2"
$ for x in `$TESTDIR/seq.py 10`
> do
> echo f$x rev2 > "f$x"
> echo d1/f$x rev2 > "d1/f$x"
> echo d2/f$x rev2 > "d2/f$x"
> hg commit -m "Commit rev2 of f$x, d1/f$x, d2/f$x"
> done
$ cd ..
narrow and shallow clone the d2 directory
$ hg clone --narrow ssh://user@dummy/master shallow --include "d2" --depth 2
requesting all changes
adding changesets
adding manifests
adding file changes
added 4 changesets with 13 changes to 10 files
new changesets *:* (glob)
updating to branch default
10 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd shallow
$ hg log -T '{rev}{if(ellipsis,"...")}: {desc}\n'
3: Commit rev2 of f10, d1/f10, d2/f10
2: Commit rev2 of f9, d1/f9, d2/f9
1: Commit rev2 of f8, d1/f8, d2/f8
0...: Commit rev2 of f7, d1/f7, d2/f7
$ hg update 0
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat d2/f7 d2/f8
d2/f7 rev2
d2/8
$ cd ..
change every upstream file once
$ cd master
$ for x in `$TESTDIR/seq.py 10`
> do
> echo f$x rev3 > "f$x"
> echo d1/f$x rev3 > "d1/f$x"
> echo d2/f$x rev3 > "d2/f$x"
> hg commit -m "Commit rev3 of f$x, d1/f$x, d2/f$x"
> done
$ cd ..
pull new changes with --depth specified. There were 10 changes to the d2
directory but the shallow pull should only fetch 3.
$ cd shallow
$ hg pull --depth 2
pulling from ssh://user@dummy/master
searching for changes
adding changesets
adding manifests
adding file changes
added 4 changesets with 10 changes to 10 files
new changesets *:* (glob)
(run 'hg update' to get a working copy)
$ hg log -T '{rev}{if(ellipsis,"...")}: {desc}\n'
7: Commit rev3 of f10, d1/f10, d2/f10
6: Commit rev3 of f9, d1/f9, d2/f9
5: Commit rev3 of f8, d1/f8, d2/f8
4...: Commit rev3 of f7, d1/f7, d2/f7
3: Commit rev2 of f10, d1/f10, d2/f10
2: Commit rev2 of f9, d1/f9, d2/f9
1: Commit rev2 of f8, d1/f8, d2/f8
0...: Commit rev2 of f7, d1/f7, d2/f7
$ hg update 4
merging d2/f1
merging d2/f2
merging d2/f3
merging d2/f4
merging d2/f5
merging d2/f6
merging d2/f7
3 files updated, 7 files merged, 0 files removed, 0 files unresolved
$ cat d2/f7 d2/f8
d2/f7 rev3
d2/f8 rev2
$ hg update 7
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat d2/f10
d2/f10 rev3
$ cd ..
cannot clone with zero or negative depth
$ hg clone --narrow ssh://user@dummy/master bad --include "d2" --depth 0
requesting all changes
remote: abort: depth must be positive, got 0
abort: pull failed on remote
[255]
$ hg clone --narrow ssh://user@dummy/master bad --include "d2" --depth -1
requesting all changes
remote: abort: depth must be positive, got -1
abort: pull failed on remote
[255]