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
test parents command
$ hg init repo
$ cd repo
no working directory
$ hg parents
$ echo a > a
$ echo b > b
$ hg ci -Amab -d '0 0'
adding a
adding b
$ echo a >> a
$ hg ci -Ama -d '1 0'
$ echo b >> b
$ hg ci -Amb -d '2 0'
$ echo c > c
$ hg ci -Amc -d '3 0'
adding c
$ hg up -C 1
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo d > c
$ hg ci -Amc2 -d '4 0'
adding c
created new head
$ hg up -C 3
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 3:02d851b7e549
user: test
date: Thu Jan 01 00:00:03 1970 +0000
summary: c
$ hg parents a
changeset: 1:d786049f033a
user: test
date: Thu Jan 01 00:00:01 1970 +0000
summary: a
hg parents c, single revision
$ hg parents c
changeset: 3:02d851b7e549
user: test
date: Thu Jan 01 00:00:03 1970 +0000
summary: c
$ hg parents -r 3 c
abort: 'c' not found in manifest!
[255]
$ hg parents -r 2
changeset: 1:d786049f033a
user: test
date: Thu Jan 01 00:00:01 1970 +0000
summary: a
$ hg parents -r 2 a
changeset: 1:d786049f033a
user: test
date: Thu Jan 01 00:00:01 1970 +0000
summary: a
$ hg parents -r 2 ../a
abort: ../a not under root '$TESTTMP/repo'
[255]
cd dir; hg parents -r 2 ../a
$ mkdir dir
$ cd dir
$ hg parents -r 2 ../a
changeset: 1:d786049f033a
user: test
date: Thu Jan 01 00:00:01 1970 +0000
summary: a
$ hg parents -r 2 path:a
changeset: 1:d786049f033a
user: test
date: Thu Jan 01 00:00:01 1970 +0000
summary: a
$ cd ..
$ hg parents -r 2 glob:a
abort: can only specify an explicit filename
[255]
merge working dir with 2 parents, hg parents c
$ HGMERGE=true hg merge
merging c
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg parents c
changeset: 3:02d851b7e549
user: test
date: Thu Jan 01 00:00:03 1970 +0000
summary: c
changeset: 4:48cee28d4b4e
tag: tip
parent: 1:d786049f033a
user: test
date: Thu Jan 01 00:00:04 1970 +0000
summary: c2
merge working dir with 1 parent, hg parents
$ hg up -C 2
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ HGMERGE=true hg merge -r 4
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg parents
changeset: 2:6cfac479f009
user: test
date: Thu Jan 01 00:00:02 1970 +0000
summary: b
changeset: 4:48cee28d4b4e
tag: tip
parent: 1:d786049f033a
user: test
date: Thu Jan 01 00:00:04 1970 +0000
summary: c2
merge working dir with 1 parent, hg parents c
$ hg parents c
changeset: 4:48cee28d4b4e
tag: tip
parent: 1:d786049f033a
user: test
date: Thu Jan 01 00:00:04 1970 +0000
summary: c2
$ cd ..