help: add internals.extensions topic
I think it's better to include the API overview in core as we now have the
internals section in our help system.
Retrieved from the wiki, and formatted as reST. Several wiki links are
removed since they are invalid in the help. The sections about example
extension are removed at all as they seemed too verbose.
https://www.mercurial-scm.org/wiki/WritingExtensions
$ cat >> $HGRCPATH << EOF
> [extensions]
> blackbox=
> rebase=
> mock=$TESTDIR/mockblackbox.py
>
> [experimental]
> evolution.createmarkers=True
> EOF
Create a repo with some tags
$ hg init repo
$ cd repo
$ echo initial > foo
$ hg -q commit -A -m initial
$ hg tag -m 'test tag' test1
$ echo first > first
$ hg -q commit -A -m first
$ hg tag -m 'test2 tag' test2
$ hg -q up -r 0
$ echo newhead > newhead
$ hg commit -A -m newhead
adding newhead
created new head
$ hg tag -m 'test head 2 tag' head2
$ hg log -G -T '{rev}:{node|short} {tags} {desc}\n'
@ 5:2942a772f72a tip test head 2 tag
|
o 4:042eb6bfcc49 head2 newhead
|
| o 3:c3cb30f2d2cd test2 tag
| |
| o 2:d75775ffbc6b test2 first
| |
| o 1:5f97d42da03f test tag
|/
o 0:55482a6fb4b1 test1 initial
Trigger tags cache population by doing something that accesses tags info
$ hg tags
tip 5:2942a772f72a
head2 4:042eb6bfcc49
test2 2:d75775ffbc6b
test1 0:55482a6fb4b1
$ cat .hg/cache/tags2-visible
5 2942a772f72a444bef4bef13874d515f50fa27b6
042eb6bfcc4909bad84a1cbf6eb1ddf0ab587d41 head2
55482a6fb4b1881fa8f746fd52cf6f096bb21c89 test1
d75775ffbc6bca1794d300f5571272879bd280da test2
Hiding a non-tip changeset should change filtered hash and cause tags recompute
$ hg debugobsolete -d '0 0' c3cb30f2d2cd0aae008cc91a07876e3c5131fd22 -u dummyuser
obsoleted 1 changesets
$ hg tags
tip 5:2942a772f72a
head2 4:042eb6bfcc49
test1 0:55482a6fb4b1
$ cat .hg/cache/tags2-visible
5 2942a772f72a444bef4bef13874d515f50fa27b6 f34fbc9a9769ba9eff5aff3d008a6b49f85c08b1
042eb6bfcc4909bad84a1cbf6eb1ddf0ab587d41 head2
55482a6fb4b1881fa8f746fd52cf6f096bb21c89 test1
$ hg blackbox -l 5
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> tags
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> 2/2 cache hits/lookups in * seconds (glob)
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> writing .hg/cache/tags2-visible with 2 tags
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> tags exited 0 after * seconds (glob)
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> blackbox -l 5
Hiding another changeset should cause the filtered hash to change
$ hg debugobsolete -d '0 0' d75775ffbc6bca1794d300f5571272879bd280da -u dummyuser
obsoleted 1 changesets
$ hg debugobsolete -d '0 0' 5f97d42da03fd56f3b228b03dfe48af5c0adf75b -u dummyuser
obsoleted 1 changesets
$ hg tags
tip 5:2942a772f72a
head2 4:042eb6bfcc49
$ cat .hg/cache/tags2-visible
5 2942a772f72a444bef4bef13874d515f50fa27b6 2fce1eec33263d08a4d04293960fc73a555230e4
042eb6bfcc4909bad84a1cbf6eb1ddf0ab587d41 head2
$ hg blackbox -l 5
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> tags
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> 1/1 cache hits/lookups in * seconds (glob)
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> writing .hg/cache/tags2-visible with 1 tags
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> tags exited 0 after * seconds (glob)
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> blackbox -l 5
Resolving tags on an unfiltered repo writes a separate tags cache
$ hg --hidden tags
tip 5:2942a772f72a
head2 4:042eb6bfcc49
test2 2:d75775ffbc6b
test1 0:55482a6fb4b1
$ cat .hg/cache/tags2
5 2942a772f72a444bef4bef13874d515f50fa27b6
042eb6bfcc4909bad84a1cbf6eb1ddf0ab587d41 head2
55482a6fb4b1881fa8f746fd52cf6f096bb21c89 test1
d75775ffbc6bca1794d300f5571272879bd280da test2
$ hg blackbox -l 5
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> --hidden tags
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> 2/2 cache hits/lookups in * seconds (glob)
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> writing .hg/cache/tags2 with 3 tags
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> --hidden tags exited 0 after * seconds (glob)
1970/01/01 00:00:00 bob @2942a772f72a444bef4bef13874d515f50fa27b6 (5000)> blackbox -l 5