[PATCH 08/11] midx-write.c: avoid directly managed temporary strbuf

[Taylor Blau <me@ttaylorr.com>]

In midx-write.c::midx_repack(), we construct the command-line arguments
for a pack-objects invocation which will combine objects from the packs
below our `--batch-size` option.

To construct the base name of the output pack, we use a temporary
strbuf, and then push the result of that onto the strvec which holds the
command-line arguments, after which point we release the strbuf.

We could replace this by doing something like:

    struct strbuf buf = STRBUF_INIT;
    strbuf_addf(&buf, "%s/pack/pack", object_dir);
    strvec_push_nodup(&cmd.args, strbuf_detach(&buf));

(combining the two separate `strbuf_addstr()` calls into a single
`strbuf_addf()`). But that is more or less an open-coded version of
strvec_pushf(), which we could use directly instead.

(Note that at the time this code was written back in ce1e4a105b4 (midx:
implement midx_repack(), 2019-06-10), strvec did not yet exist, so the
above example would have replaced the last line with:

    argv_array_push_nodup(&cmd.args, strbuf_detach(&buf));

, but the code is otherwise unchanged).

Avoid directly managing the temporary strbuf used to construct the
base name for pack-object's command-line arguments, and instead use the
purpose-built `strvec_pushf()` instead.

Signed-off-by: Taylor Blau <me@ttaylorr.com>
---
 midx-write.c | 7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/midx-write.c b/midx-write.c
index c812156cbd..89e325d08e 100644
--- a/midx-write.c
+++ b/midx-write.c
@@ -1446,7 +1446,6 @@ int midx_repack(struct repository *r, const char *object_dir, size_t batch_size,
 	unsigned char *include_pack;
 	struct child_process cmd = CHILD_PROCESS_INIT;
 	FILE *cmd_in;
-	struct strbuf base_name = STRBUF_INIT;
 	struct multi_pack_index *m = lookup_multi_pack_index(r, object_dir);
 
 	/*
@@ -1473,10 +1472,6 @@ int midx_repack(struct repository *r, const char *object_dir, size_t batch_size,
 
 	strvec_push(&cmd.args, "pack-objects");
 
-	strbuf_addstr(&base_name, object_dir);
-	strbuf_addstr(&base_name, "/pack/pack");
-	strvec_push(&cmd.args, base_name.buf);
-
 	if (delta_base_offset)
 		strvec_push(&cmd.args, "--delta-base-offset");
 	if (use_delta_islands)
@@ -1487,7 +1482,7 @@ int midx_repack(struct repository *r, const char *object_dir, size_t batch_size,
 	else
 		strvec_push(&cmd.args, "-q");
 
-	strbuf_release(&base_name);
+	strvec_pushf(&cmd.args, "%s/pack/pack", object_dir);
 
 	cmd.git_cmd = 1;
 	cmd.in = cmd.out = -1;
-- 
2.44.0.290.g736be63234b