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 EOL update
$ cat >> $HGRCPATH <<EOF
> [diff]
> git = 1
> EOF
$ seteol () {
> if [ $1 = "LF" ]; then
> EOL='\n'
> else
> EOL='\r\n'
> fi
> }
$ makerepo () {
> echo
> echo "# ==== setup repository ===="
> echo '% hg init'
> hg init repo
> cd repo
>
> cat > .hgeol <<EOF
> [patterns]
> **.txt = LF
> EOF
>
> printf "first\nsecond\nthird\n" > a.txt
> hg commit --addremove -m 'LF commit'
>
> cat > .hgeol <<EOF
> [patterns]
> **.txt = CRLF
> EOF
>
> printf "first\r\nsecond\r\nthird\r\n" > a.txt
> hg commit -m 'CRLF commit'
>
> cd ..
> }
$ dotest () {
> seteol $1
>
> echo
> echo "% hg clone repo repo-$1"
> hg clone --noupdate repo repo-$1
> cd repo-$1
>
> cat > .hg/hgrc <<EOF
> [extensions]
> eol =
> EOF
>
> hg update
>
> echo '% a.txt (before)'
> cat a.txt
>
> printf "first${EOL}third${EOL}" > a.txt
>
> echo '% a.txt (after)'
> cat a.txt
> echo '% hg diff'
> hg diff
>
> echo '% hg update 0'
> hg update 0
>
> echo '% a.txt'
> cat a.txt
> echo '% hg diff'
> hg diff
>
>
> cd ..
> rm -r repo-$1
> }
$ makerepo
# ==== setup repository ====
% hg init
adding .hgeol
adding a.txt
$ dotest LF
% hg clone repo repo-LF
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
% a.txt (before)
first\r (esc)
second\r (esc)
third\r (esc)
% a.txt (after)
first
third
% hg diff
diff --git a/a.txt b/a.txt
--- a/a.txt
+++ b/a.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
% hg update 0
merging a.txt
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
% a.txt
first
third
% hg diff
diff --git a/a.txt b/a.txt
--- a/a.txt
+++ b/a.txt
@@ -1,3 +1,2 @@
first
-second
third
$ dotest CRLF
% hg clone repo repo-CRLF
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
% a.txt (before)
first\r (esc)
second\r (esc)
third\r (esc)
% a.txt (after)
first\r (esc)
third\r (esc)
% hg diff
diff --git a/a.txt b/a.txt
--- a/a.txt
+++ b/a.txt
@@ -1,3 +1,2 @@
first\r (esc)
-second\r (esc)
third\r (esc)
% hg update 0
merging a.txt
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
% a.txt
first
third
% hg diff
diff --git a/a.txt b/a.txt
--- a/a.txt
+++ b/a.txt
@@ -1,3 +1,2 @@
first
-second
third
$ rm -r repo