Wez Furlong <wez@fb.com> [Thu, 18 May 2017 12:49:10 -0700] rev 32374
fsmonitor: don't attempt state-leave if we didn't state-enter
The state-enter command may not have been successful; for example, the watchman
client session may have timed out if the user was busy/idle for a long period
during a merge conflict resolution earlier in processing a rebase for a stack
of diffs.
It's cleaner (from the perspective of the watchman logs) to avoid issuing the
state-leave command in these cases.
Test Plan:
ran
`hg rebase --tool :merge -r '(draft() & date(-14)) - master::' -d master`
and didn't observe any errors in the watchman logs or in the output from
`watchman -p -j <<<'["subscribe", "/data/users/wez/fbsource", "wez", {"expression": ["name", ".hg/updatestate"]}]'`
Wez Furlong <wez@fb.com> [Thu, 18 May 2017 12:48:07 -0700] rev 32373
fsmonitor: acquire localrepo.wlock prior to emitting hg.update state
we see some weird things in the watchman logs where the mercurial
process is seemingly confused about which hg.update state it is publishing
through watchman.
On closer examination, we're seeing conflicting pids for the clients involved
and this implies a race.
To resolve this, we extend the wlock around the state-enter/state-leave
events that are emitted to watchman.
Test Plan:
Some manual testing:
In one window, run this, and then checkout a different rev:
```
$ watchman -p -j <<<'["subscribe", "/data/users/wez/fbsource", "wez", {"expression": ["name", ".hg/updatestate"]}]'
{
"version": "4.9.0",
"subscribe": "wez",
"clock": "c:1495034090:814028:1:312576"
}
{
"state-enter": "hg.update",
"version": "4.9.0",
"clock": "c:1495034090:814028:1:312596",
"unilateral": true,
"subscription": "wez",
"metadata": {
"status": "ok",
"distance": 125,
"rev": "a1275d79ffa6c58b53116c8ec401c275ca6c1e2a",
"partial": false
},
"root": "/data/users/wez/fbsource"
}
{
"root": "/data/users/wez/fbsource",
"metadata": {
"status": "ok",
"distance": 125,
"rev": "a1275d79ffa6c58b53116c8ec401c275ca6c1e2a",
"partial": false
},
"subscription": "wez",
"unilateral": true,
"version": "4.9.0",
"clock": "c:1495034090:814028:1:312627",
"state-leave": "hg.update"
}
```
Tailed the watchman log file and looked for invalid state assertion errors,
then ran my `rebase-all` script to update/rebase all of my heads.
Didn't trigger the error condition (but couldn't reliably trigger it previously
anyway), and the output captured above shows that the states are being emitted
correctly.
Pierre-Yves David <pierre-yves.david@octobus.net> [Fri, 19 May 2017 13:12:42 +0200] rev 32372
obsolete: move the 'isenabled' function at the top of the file
That is a simple and important function so having it at the top next to the
related constant seems better.