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.
Tests of the file helper tool
$ f -h
?sage: f [options] [filenames] (glob)
?ptions: (glob)
-h, --help show this help message and exit
-t, --type show file type (file or directory)
-m, --mode show file mode
-l, --links show number of links
-s, --size show size of file
-n NEWER, --newer=NEWER
check if file is newer (or same)
-r, --recurse recurse into directories
-S, --sha1 show sha1 hash of the content
--raw-sha1 show raw bytes of the sha1 hash of the content
--sha256 show sha256 hash of the content
-M, --md5 show md5 hash of the content
-D, --dump dump file content
-H, --hexdump hexdump file content
-B BYTES, --bytes=BYTES
number of characters to dump
-L LINES, --lines=LINES
number of lines to dump
-q, --quiet no default output
$ mkdir dir
$ cd dir
$ f --size
size=0
$ echo hello | f --md5 --size
size=6, md5=b1946ac92492d2347c6235b4d2611184
$ f foo
foo: file not found
$ echo foo > foo
$ f foo
foo:
$ f --sha1 foo
foo: sha1=f1d2d2f924e986ac86fdf7b36c94bcdf32beec15
$ f --sha256 foo
foo: sha256=b5bb9d8014a0f9b1d61e21e796d78dccdf1352f23cd32812f4850b878ae4944c
#if symlink
$ f foo --mode
foo: mode=644
#endif
#if no-windows
$ "$PYTHON" $TESTDIR/seq.py 10 > bar
#else
Convert CRLF -> LF for consistency
$ "$PYTHON" $TESTDIR/seq.py 10 | sed "s/$//" > bar
#endif
#if unix-permissions symlink
$ chmod +x bar
$ f bar --newer foo --mode --type --size --dump --links --bytes 7
bar: file, size=21, mode=755, links=1, newer than foo
>>>
1
2
3
4
<<< no trailing newline
#endif
#if unix-permissions
$ ln bar baz
$ f bar -n baz -l --hexdump -t --sha1 --lines=9 -B 20
bar: file, links=2, newer than baz, sha1=612ca68d0305c821750a
0000: 31 0a 32 0a 33 0a 34 0a 35 0a 36 0a 37 0a 38 0a |1.2.3.4.5.6.7.8.|
0010: 39 0a |9.|
$ rm baz
#endif
#if unix-permissions symlink
$ ln -s yadda l
$ f . --recurse -MStmsB4
.: directory with 3 files, mode=755
./bar: file, size=21, mode=755, md5=3b03, sha1=612c
./foo: file, size=4, mode=644, md5=d3b0, sha1=f1d2
./l: link, size=5, md5=2faa, sha1=af93
#endif
$ f --quiet bar -DL 3
1
2
3
$ cd ..
Yadda is a symlink
$ f -qr dir -HB 17
dir: directory with 3 files (symlink !)
dir: directory with 2 files (no-symlink !)
dir/bar:
0000: 31 0a 32 0a 33 0a 34 0a 35 0a 36 0a 37 0a 38 0a |1.2.3.4.5.6.7.8.|
0010: 39 |9|
dir/foo:
0000: 66 6f 6f 0a |foo.|
dir/l: (symlink !)
0000: 79 61 64 64 61 |yadda| (symlink !)