util: extract compression code in `mercurial.utils.compression`
The code seems large enough to be worth extracting. This is similar to what was
done for various module in `mercurial/utils/`.
Since None of the compression logic takes a `ui` objet, issuing deprecation
warning is tricky. Luckly the logic does not seems to have many external users.
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init a
$ cd a
$ echo 'base' > base
$ hg ci -Ambase
adding base
$ hg qnew -mmqbase mqbase
$ hg qrename mqbase renamed
$ mkdir .hg/patches/foo
$ hg qrename renamed foo
$ hg qseries
foo/renamed
$ ls .hg/patches/foo
renamed
$ mkdir .hg/patches/bar
$ hg qrename foo/renamed bar
$ hg qseries
bar/renamed
$ ls .hg/patches/bar
renamed
$ hg qrename bar/renamed baz
$ hg qseries
baz
$ ls .hg/patches/baz
.hg/patches/baz
$ hg qrename baz new/dir
$ hg qseries
new/dir
$ ls .hg/patches/new/dir
.hg/patches/new/dir
$ cd ..
Test patch being renamed before committed:
$ hg init b
$ cd b
$ hg qinit -c
$ hg qnew x
$ hg qrename y
$ hg qcommit -m rename
$ cd ..
Test overlapping renames (issue2388)
$ hg init c
$ cd c
$ hg qinit -c
$ echo a > a
$ hg add
adding a
$ hg qnew patcha
$ echo b > b
$ hg add
adding b
$ hg qnew patchb
$ hg ci --mq -m c1
$ hg qrename patchb patchc
$ hg qrename patcha patchb
$ hg st --mq
M patchb
M series
A patchc
R patcha
$ cd ..
Test renames with mq repo (issue2097)
$ hg init issue2097
$ cd issue2097
$ hg qnew p0
$ (cd .hg/patches && hg init)
$ hg qren p0 p1
$ hg debugstate --mq
$ hg ci --mq -mq0
nothing changed
[1]
$ cd ..
Test renaming to a folded patch (issue3058)
$ hg init issue3058
$ cd issue3058
$ hg init --mq
$ echo a > a
$ hg add a
$ hg qnew adda
$ echo b >> a
$ hg qnew addb
$ hg qpop
popping addb
now at: adda
$ hg ci --mq -m "save mq"
$ hg qfold addb
$ hg qmv addb
$ cat .hg/patches/addb
# HG changeset patch
# Parent 0000000000000000000000000000000000000000
diff -r 000000000000 a
--- /dev/null * (glob)
+++ b/a * (glob)
@@ -0,0 +1,2 @@
+a
+b
$ cd ..