Commit Graph

6 Commits

Author SHA1 Message Date
Junio C Hamano
8a40af9cab Merge branch 'rs/ls-tree-path-expansion-fix'
"git ls-tree --format='%(path) %(path)' $tree $path" showed the
path three times, which has been corrected.

* rs/ls-tree-path-expansion-fix:
  ls-tree: remove dead store and strbuf for quote_c_style()
  ls-tree: fix expansion of repeated %(path)
2023-01-23 13:39:50 -08:00
René Scharfe
16fb5c54bd ls-tree: fix expansion of repeated %(path)
expand_show_tree() borrows the base strbuf given to us by read_tree() to
build the full path of the current entry when handling %(path).  Only
its indirect caller, show_tree_fmt(), removes the added entry name.
That works fine as long as %(path) is only included once in the format
string, but accumulates duplicates if it's repeated:

   $ git ls-tree --format='%(path) %(path) %(path)' HEAD M*
   Makefile MakefileMakefile MakefileMakefileMakefile

Reset the length after each use to get the same expansion every time;
here's the behavior with this patch:

   $ ./git ls-tree --format='%(path) %(path) %(path)' HEAD M*
   Makefile Makefile Makefile

Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-14 19:22:26 -08:00
Teng Long
cf4936ed74 t3104: remove shift code in 'test_ls_tree_format'
In t3104-ls-tree-format.sh, There is a legacy 'shift 2' code
and the relevant code block no longer depends on it anymore,
so let's remove it for a small cleanup.

Signed-off-by: Teng Long <dyroneteng@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-01-13 15:09:23 -08:00
Ævar Arnfjörð Bjarmason
1d232d38bd ls-tree: test for the regression in 9c4d58ff2c
Add a test for the regression introduced in my 9c4d58ff2c (ls-tree:
split up "fast path" callbacks, 2022-03-23) and fixed in
350296cc78 (ls-tree: `-l` should not imply recursive listing,
2022-04-04), and test for the test of ls-tree option/mode combinations
to make sure we don't have other blind spots.

The setup for these tests can be shared with those added in the
1041d58b4d (Merge branch 'tl/ls-tree-oid-only', 2022-04-04) topic, so
let's create a new t/lib-t3100.sh to help them share data.

The existing tests in "t3104-ls-tree-format.sh" didn't deal with a
submodule, which they'll now encounter with as the
setup_basic_ls_tree_data() sets one up.

This extensive testing should give us confidence that there were no
further regressions in this area. The lack of testing was noted back
in [1], but unfortunately we didn't cover that blind-spot before
9c4d58ff2c.

1. https://lore.kernel.org/git/211115.86o86lqe3c.gmgdl@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-06-03 09:47:11 -07:00
Ævar Arnfjörð Bjarmason
455923e0a1 ls-tree: introduce "--format" option
Add a --format option to ls-tree. It has an existing default output,
and then --long and --name-only options to emit the default output
along with the objectsize and, or to only emit object paths.

Rather than add --type-only, --object-only etc. we can just support a
--format using a strbuf_expand() similar to "for-each-ref
--format". We might still add such options in the future for
convenience.

The --format implementation is slower than the existing code, but this
change does not cause any performance regressions. We'll leave the
existing show_tree() unchanged, and only run show_tree_fmt() in if
a --format different than the hardcoded built-in ones corresponding to
the existing modes is provided.

I.e. something like the "--long" output would be much slower with
this, mainly due to how we need to allocate various things to do with
quote.c instead of spewing the output directly to stdout.

The new option of '--format' comes from Ævar Arnfjörð Bjarmasonn's
idea and suggestion, this commit makes modifications in terms of the
original discussion on community [1].

In [1] there was a "GIT_TEST_LS_TREE_FORMAT_BACKEND" variable to
ensure that we had test coverage for passing tests that would
otherwise use show_tree() through show_tree_fmt(), and thus that the
formatting mechanism could handle all the same cases as the
non-formatting options.

Somewhere in subsequent re-rolls of that we seem to have drifted away
from what the goal of these tests should be. We're trying to ensure
correctness of show_tree_fmt(). We can't tell if we "hit [the]
fast-path" here, and instead of having an explicit test for that, we
can just add it to something our "test_ls_tree_format" tests for.

Here is the statistics about performance tests:

1. Default format (hitten the builtin formats):

    "git ls-tree <tree-ish>" vs "--format='%(mode) %(type) %(object)%x09%(file)'"

    $hyperfine --warmup=10 "/opt/git/master/bin/git ls-tree -r HEAD"
    Benchmark 1: /opt/git/master/bin/git ls-tree -r HEAD
    Time (mean ± σ):     105.2 ms ±   3.3 ms    [User: 84.3 ms, System: 20.8 ms]
    Range (min … max):    99.2 ms … 113.2 ms    28 runs

    $hyperfine --warmup=10 "/opt/git/ls-tree-oid-only/bin/git ls-tree -r --format='%(mode) %(type) %(object)%x09%(file)'  HEAD"
    Benchmark 1: /opt/git/ls-tree-oid-only/bin/git ls-tree -r --format='%(mode) %(type) %(object)%x09%(file)'  HEAD
    Time (mean ± σ):     106.4 ms ±   2.7 ms    [User: 86.1 ms, System: 20.2 ms]
    Range (min … max):   100.2 ms … 110.5 ms    29 runs

2. Default format includes object size (hitten the builtin formats):

    "git ls-tree -l <tree-ish>" vs "--format='%(mode) %(type) %(object) %(size:padded)%x09%(file)'"

    $hyperfine --warmup=10 "/opt/git/master/bin/git ls-tree -r -l HEAD"
    Benchmark 1: /opt/git/master/bin/git ls-tree -r -l HEAD
    Time (mean ± σ):     335.1 ms ±   6.5 ms    [User: 304.6 ms, System: 30.4 ms]
    Range (min … max):   327.5 ms … 348.4 ms    10 runs

    $hyperfine --warmup=10 "/opt/git/ls-tree-oid-only/bin/git ls-tree -r --format='%(mode) %(type) %(object) %(size:padded)%x09%(file)'  HEAD"
    Benchmark 1: /opt/git/ls-tree-oid-only/bin/git ls-tree -r --format='%(mode) %(type) %(object) %(size:padded)%x09%(file)'  HEAD
    Time (mean ± σ):     337.2 ms ±   8.2 ms    [User: 309.2 ms, System: 27.9 ms]
    Range (min … max):   328.8 ms … 349.4 ms    10 runs

Links:
	[1] https://public-inbox.org/git/RFC-patch-6.7-eac299f06ff-20211217T131635Z-avarab@gmail.com/
	[2] https://lore.kernel.org/git/cb717d08be87e3239117c6c667cb32caabaad33d.1646390152.git.dyroneteng@gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Teng Long <dyroneteng@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-23 11:38:40 -07:00
Teng Long
cab851c2f8 ls-tree: support --object-only option for "git-ls-tree"
'--object-only' is an alias for '--format=%(objectname)'. It cannot
be used together other format-altering options like '--name-only',
'--long' or '--format', they are mutually exclusive.

The "--name-only" option outputs <filepath> only. Likewise, <objectName>
is another high frequency used field, so implement '--object-only' option
will bring intuitive and clear semantics for this scenario. Using
'--format=%(objectname)' we can achieve a similar effect, but the former
is with a lower learning cost(without knowing the format requirement
of '--format' option).

Even so, if a user is prefer to use "--format=%(objectname)", this is entirely
welcome because they are not only equivalent in function, but also have almost
identical performance. The reason is this commit also add the specific of
"--format=%(objectname)" to the current fast-pathes (builtin formats) to
avoid running unnecessary parsing mechanisms.

The following performance benchmarks are based on torvalds/linux.git:

  When hit the fast-path:

      Benchmark 1: /opt/git/ls-tree-oid-only/bin/git ls-tree -r --object-only HEAD
        Time (mean ± σ):      83.6 ms ±   2.0 ms    [User: 59.4 ms, System: 24.1 ms]
        Range (min … max):    80.4 ms …  87.2 ms    35 runs

      Benchmark 1: /opt/git/ls-tree-oid-only/bin/git ls-tree -r --format='%(objectname)' HEAD
        Time (mean ± σ):      84.1 ms ±   1.8 ms    [User: 61.7 ms, System: 22.3 ms]
        Range (min … max):    80.9 ms …  87.5 ms    35 runs

  But for a customized format, it will be slower:

       Benchmark 1: /opt/git/ls-tree-oid-only/bin/git ls-tree -r --format='oid: %(objectname)' HEAD
         Time (mean ± σ):      96.5 ms ±   2.5 ms    [User: 72.9 ms, System: 23.5 ms]
  	 Range (min … max):    93.1 ms … 104.1 ms    31 runs

Helped-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Teng Long <dyroneteng@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-23 11:38:40 -07:00