view tests/test-tools.t @ 30446:b324b4e431e5

posix: give checkexec a fast path; keep the check files and test read only

Before, Mercurial would create a new temporary file every time, stat it, change
its exec mode, stat it again, and delete it. Most of this dance was done to
handle the rare and not-so-essential case of VFAT mounts on unix. The cost of
that was paid by the much more common and important case of using normal file
systems.

Instead, try to create and preserve .hg/cache/checkisexec and
.hg/cache/checknoexec with and without exec flag set. If the files exist and
have correct exec flags set, we can conclude that that file system supports the
exec flag. Best case, the whole exec check can thus be done with two stat
calls. Worst case, we delete the wrong files and check as usual. That will be
because temporary loss of exec bit or on file systems without support for the
exec bit. In that case we check as we did before, with the additional overhead
of one extra stat call.

It is possible that this different test algorithm in some cases on odd file
systems will give different behaviour. Again, I think it will be rare and
special cases and I think it is worth the risk.

test-clone.t happens to show the situation where checkisexec is left behind
from the old style check, while checknoexec only will be created next time a
exec check will be performed.

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
    -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:

#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
#if symlink
  $ f -qr dir -HB 17
  dir: directory with 3 files
  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:
  0000: 79 61 64 64 61                                  |yadda|
#else
  $ f -qr dir -HB 17
  dir: directory with 2 files (esc)
  dir/bar: (glob)
  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: (glob)
  0000: 66 6f 6f 0a                                     |foo.|
#endif