branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
$ hg init repo
$ cd repo
$ echo 0 > a
$ echo 0 > b
$ hg ci -A -m m
adding a
adding b
$ hg rm a
$ hg cat a
0
$ hg cat --decode a # more tests in test-encode
0
$ echo 1 > b
$ hg ci -m m
$ echo 2 > b
$ hg cat -r 0 a
0
$ hg cat -r 0 b
0
$ hg cat -r 1 a
a: no such file in rev 7040230c159c
[1]
$ hg cat -r 1 b
1
Test multiple files
$ echo 3 > c
$ hg ci -Am addmore c
$ hg cat b c
1
3
$ hg cat .
1
3
$ hg cat . c
1
3
Test fileset
$ hg cat 'set:not(b) or a'
3
$ hg cat 'set:c or b'
1
3
$ mkdir tmp
$ hg cat --output tmp/HH_%H c
$ hg cat --output tmp/RR_%R c
$ hg cat --output tmp/h_%h c
$ hg cat --output tmp/r_%r c
$ hg cat --output tmp/%s_s c
$ hg cat --output tmp/%d%%_d c
$ hg cat --output tmp/%p_p c
$ hg log -r . --template "{rev}: {node|short}\n"
2: 45116003780e
$ find tmp -type f | sort
tmp/.%_d
tmp/HH_45116003780e3678b333fb2c99fa7d559c8457e9
tmp/RR_2
tmp/c_p
tmp/c_s
tmp/h_45116003780e
tmp/r_2
Test template output
$ hg --cwd tmp cat ../b ../c -T '== {path|relpath} ({path}) r{rev} ==\n{data}'
== ../b (b) r2 ==
1
== ../c (c) r2 ==
3
$ hg cat b c -Tjson --output -
[
{
"data": "1\n",
"path": "b"
},
{
"data": "3\n",
"path": "c"
}
]
$ hg cat b c -Tjson --output 'tmp/%p.json'
$ cat tmp/b.json
[
{
"data": "1\n",
"path": "b"
}
]
$ cat tmp/c.json
[
{
"data": "3\n",
"path": "c"
}
]
Test working directory
$ echo b-wdir > b
$ hg cat -r 'wdir()' b
b-wdir
Environment variables are not visible by default
$ PATTERN='t4' hg log -r '.' -T "{ifcontains('PATTERN', envvars, 'yes', 'no')}\n"
no
Environment variable visibility can be explicit
$ PATTERN='t4' hg log -r '.' -T "{envvars % '{key} -> {value}\n'}" \
> --config "experimental.exportableenviron=PATTERN"
PATTERN -> t4
Test behavior of output when directory structure does not already exist
$ mkdir foo
$ echo a > foo/a
$ hg add foo/a
$ hg commit -qm "add foo/a"
$ hg cat --output "output/%p" foo/a
$ cat output/foo/a
a