hg: obtain lock when creating share from pooled repo (issue5104)
There are race conditions between clients performing a shared clone
to pooled storage:
1) Clients race to create the new shared repo in the pool directory
2) 1 client is seeding the repo in the pool directory and another goes
to share it before it is fully cloned
We prevent these race conditions by obtaining a lock in the pool
directory that is derived from the name of the repo we will be
accessing.
To test this, a simple generic "lockdelay" extension has been added.
The extension inserts an optional, configurable delay before or after
lock acquisition. In the test, we delay 2 seconds after lock acquisition
in the first process and 1 second before lock acquisition in the 2nd
process. This means the first process has 1s to obtain the lock. There
is a race condition here. If we encounter it in the wild, we could
change the dummy extension to wait on the lock file to appear instead
of relying on timing. But that's more complicated. Let's see what
happens first.
Set up a repo
$ cat <<EOF >> $HGRCPATH
> [ui]
> interactive = true
> [experimental]
> crecord = true
> crecordtest = testModeCommands
> EOF
$ hg init a
$ cd a
Committing some changes but stopping on the way
$ echo "a" > a
$ hg add a
$ cat <<EOF >testModeCommands
> TOGGLE
> X
> EOF
$ hg commit -i -m "a" -d "0 0"
no changes to record
$ hg tip
changeset: -1:000000000000
tag: tip
user:
date: Thu Jan 01 00:00:00 1970 +0000
Committing some changes
$ cat <<EOF >testModeCommands
> X
> EOF
$ hg commit -i -m "a" -d "0 0"
$ hg tip
changeset: 0:cb9a9f314b8b
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: a
Check that commit -i works with no changes
$ hg commit -i
no changes to record
Committing only one file
$ echo "a" >> a
>>> open('b', 'wb').write("1\n2\n3\n4\n5\n6\n7\n8\n9\n10\n")
$ hg add b
$ cat <<EOF >testModeCommands
> TOGGLE
> KEY_DOWN
> X
> EOF
$ hg commit -i -m "one file" -d "0 0"
$ hg tip
changeset: 1:fb2705a663ea
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: one file
$ hg cat -r tip a
a
$ cat a
a
a
Committing only one hunk while aborting edition of hunk
- Untoggle all the hunks, go down to the second file
- unfold it
- go down to second hunk (1 for the first hunk, 1 for the first hunkline, 1 for the second hunk, 1 for the second hunklike)
- toggle the second hunk
- toggle on and off the amend mode (to check that it toggles off)
- edit the hunk and quit the editor immediately with non-zero status
- commit
$ printf "printf 'editor ran\n'; exit 1" > editor.sh
$ echo "x" > c
$ cat b >> c
$ echo "y" >> c
$ mv c b
$ cat <<EOF >testModeCommands
> A
> KEY_DOWN
> f
> KEY_DOWN
> KEY_DOWN
> KEY_DOWN
> KEY_DOWN
> TOGGLE
> a
> a
> e
> X
> EOF
$ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg commit -i -m "one hunk" -d "0 0"
editor ran
$ rm editor.sh
$ hg tip
changeset: 2:7d10dfe755a8
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: one hunk
$ hg cat -r tip b
1
2
3
4
5
6
7
8
9
10
y
$ cat b
x
1
2
3
4
5
6
7
8
9
10
y
$ hg commit -m "other hunks"
$ hg tip
changeset: 3:a6735021574d
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: other hunks
$ hg cat -r tip b
x
1
2
3
4
5
6
7
8
9
10
y
Newly added files can be selected with the curses interface
$ hg update -C .
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo "hello" > x
$ hg add x
$ cat <<EOF >testModeCommands
> TOGGLE
> TOGGLE
> X
> EOF
$ hg st
A x
? testModeCommands
$ hg commit -i -m "newly added file" -d "0 0"
$ hg st
? testModeCommands
Amend option works
$ echo "hello world" > x
$ hg diff -c .
diff -r a6735021574d -r 2b0e9be4d336 x
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/x Thu Jan 01 00:00:00 1970 +0000
@@ -0,0 +1,1 @@
+hello
$ cat <<EOF >testModeCommands
> a
> X
> EOF
$ hg commit -i -m "newly added file" -d "0 0"
saved backup bundle to $TESTTMP/a/.hg/strip-backup/2b0e9be4d336-28bbe4e2-amend-backup.hg (glob)
$ hg diff -c .
diff -r a6735021574d -r c1d239d165ae x
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/x Thu Jan 01 00:00:00 1970 +0000
@@ -0,0 +1,1 @@
+hello world
Editing a hunk puts you back on that hunk when done editing (issue5041)
To do that, we change two lines in a file, pretend to edit the second line,
exit, toggle the line selected at the end of the edit and commit.
The first line should be recorded if we were put on the second line at the end
of the edit.
$ hg update -C .
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo "foo" > x
$ echo "hello world" >> x
$ echo "bar" >> x
$ cat <<EOF >testModeCommands
> f
> KEY_DOWN
> KEY_DOWN
> KEY_DOWN
> KEY_DOWN
> e
> TOGGLE
> X
> EOF
$ printf "printf 'editor ran\n'; exit 0" > editor.sh
$ HGEDITOR="\"sh\" \"`pwd`/editor.sh\"" hg commit -i -m "edit hunk" -d "0 0"
editor ran
$ hg cat -r . x
foo
hello world