'--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@xxxxxxxxx>
Signed-off-by: Teng Long <dyroneteng@xxxxxxxxx>
---
Documentation/git-ls-tree.txt | 11 ++++++++++-
builtin/ls-tree.c | 13 ++++++++++++-
t/t3103-ls-tree-misc.sh | 7 +++++--
t/t3104-ls-tree-format.sh | 9 +++++++++
4 files changed, 36 insertions(+), 4 deletions(-)
diff --git a/Documentation/git-ls-tree.txt b/Documentation/git-ls-tree.txt
index db29a9efb5..1aea998e72 100644
--- a/Documentation/git-ls-tree.txt
+++ b/Documentation/git-ls-tree.txt
@@ -10,7 +10,7 @@ SYNOPSIS
--------
[verse]
'git ls-tree' [-d] [-r] [-t] [-l] [-z]
- [--name-only] [--name-status] [--full-name] [--full-tree] [--abbrev[=<n>]] [--format=<format>]
+ [--name-only] [--name-status] [--object-only] [--full-name] [--full-tree] [--abbrev[=<n>]] [--format=<format>]
<tree-ish> [<path>...]
DESCRIPTION
@@ -59,6 +59,15 @@ OPTIONS
--name-only::
--name-status::
List only filenames (instead of the "long" output), one per line.
+ Cannot be combined with `--object-only`.
+
+--object-only::
+ List only names of the objects, one per line. Cannot be combined
+ with `--name-only` or `--name-status`.
+ This is equivalent to specifying `--format='%(objectname)'`, but
+ for both this option and that exact format the command takes a
+ hand-optimized codepath instead of going through the generic
+ formatting mechanism.
--abbrev[=<n>]::
Instead of showing the full 40-byte hexadecimal object
diff --git a/builtin/ls-tree.c b/builtin/ls-tree.c
index 8a1bf2fa4d..3474f8c3d6 100644
--- a/builtin/ls-tree.c
+++ b/builtin/ls-tree.c
@@ -24,7 +24,6 @@ static struct pathspec pathspec;
static int chomp_prefix;
static const char *ls_tree_prefix;
static const char *format;
-
struct show_tree_data {
unsigned mode;
enum object_type type;
@@ -42,6 +41,7 @@ static enum ls_tree_cmdmode {
MODE_DEFAULT = 0,
MODE_LONG,
MODE_NAME_ONLY,
+ MODE_OBJECT_ONLY,
} cmdmode;
static void expand_objectsize(struct strbuf *line, const struct object_id *oid,
@@ -227,6 +227,11 @@ static int show_tree(const struct object_id *oid, struct strbuf *base,
return recurse;
}
+ if (cmdmode == MODE_OBJECT_ONLY) {
+ printf("%s%c", find_unique_abbrev(oid, abbrev), line_termination);
+ return recurse;
+ }
+
if (cmdmode == MODE_NAME_ONLY) {
baselen = base->len;
strbuf_addstr(base, pathname);
@@ -264,6 +269,10 @@ static struct ls_tree_cmdmode_to_fmt ls_tree_cmdmode_format[] = {
.mode = MODE_NAME_ONLY, /* And MODE_NAME_STATUS */
.fmt = "%(path)",
},
+ {
+ .mode = MODE_OBJECT_ONLY,
+ .fmt = "%(objectname)",
+ },
{ 0 },
};
@@ -288,6 +297,8 @@ int cmd_ls_tree(int argc, const char **argv, const char *prefix)
MODE_NAME_ONLY),
OPT_CMDMODE(0, "name-status", &cmdmode, N_("list only filenames"),
MODE_NAME_ONLY),
+ OPT_CMDMODE(0, "object-only", &cmdmode, N_("list only objects"),
+ MODE_OBJECT_ONLY),
OPT_SET_INT(0, "full-name", &chomp_prefix,
N_("use full path names"), 0),
OPT_BOOL(0, "full-tree", &full_tree,
diff --git a/t/t3103-ls-tree-misc.sh b/t/t3103-ls-tree-misc.sh
index d9d7fa932f..d979c0df5d 100755
--- a/t/t3103-ls-tree-misc.sh
+++ b/t/t3103-ls-tree-misc.sh
@@ -25,11 +25,14 @@ test_expect_success 'ls-tree fails with non-zero exit code on broken tree' '
for opts in \
"--name-only --long" \
- "--name-status --long"
+ "--name-status --long" \
+ "--name-only --object-only" \
+ "--name-status --object-only" \
+ "--object-only --long" \
+ "--object-only --format"
do
test_expect_success "usage: incompatible options: $opts" '
test_expect_code 129 git ls-tree $opts $tree
'
done
-
test_done
diff --git a/t/t3104-ls-tree-format.sh b/t/t3104-ls-tree-format.sh
index 7f1eb699d3..0769a933d6 100755
--- a/t/t3104-ls-tree-format.sh
+++ b/t/t3104-ls-tree-format.sh
@@ -49,6 +49,15 @@ test_ls_tree_format \
"%(path)" \
"--name-only"
+test_ls_tree_format \
+ "%(objectname)" \
+ "--object-only"
+
+test_ls_tree_format \
+ "%(objectname)" \
+ "--object-only --abbrev" \
+ "--abbrev"
+
test_ls_tree_format \
"%(objectmode) %(objecttype) %(objectname)%x09%(path)" \
"-t" \
--
2.34.1.404.g92931a4a2c.dirty
