Re: [PATCH v2 04/11] reftable/stack: verify that `reftable_stack_add()` uses auto-compaction
From: Taylor Blau <hidden>
Date: 2023-12-08 21:35:45
On Fri, Dec 08, 2023 at 03:53:10PM +0100, Patrick Steinhardt wrote:
quoted hunk ↗ jump to hunk
diff --git a/reftable/stack_test.c b/reftable/stack_test.c index 0644c8ad2e..c979d177c2 100644 --- a/reftable/stack_test.c +++ b/reftable/stack_test.c@@ -850,6 +850,52 @@ static void test_reftable_stack_auto_compaction(void) clear_dir(dir); } +static void test_reftable_stack_add_performs_auto_compaction(void) +{ + struct reftable_write_options cfg = { 0 }; + struct reftable_stack *st = NULL; + char *dir = get_tmp_dir(__LINE__); + int err, i, n = 20; + + err = reftable_new_stack(&st, dir, cfg); + EXPECT_ERR(err); + + for (i = 0; i <= n; i++) { + struct reftable_ref_record ref = { + .update_index = reftable_stack_next_update_index(st), + .value_type = REFTABLE_REF_SYMREF, + .value.symref = "master", + }; + char name[100]; + + /* + * Disable auto-compaction for all but the last runs. Like this + * we can ensure that we indeed honor this setting and have + * better control over when exactly auto compaction runs. + */ + st->disable_auto_compact = i != n; + + snprintf(name, sizeof(name), "branch%04d", i); + ref.refname = name;
Is there a reason that we have to use snprintf() here and not a strbuf?
I would have expected to see something like:
struct strbuf buf = STRBUF_INIT;
/* ... */
strbuf_addf(&buf, "branch%04d", i);
ref.refname = strbuf_detach(&buf, NULL);
I guess it doesn't matter too much, but I think if we can avoid using
snprintf(), it's worth doing. If we must use snprintf() here, we should
probably use Git's xsnprintf() instead.
+ err = reftable_stack_add(st, &write_test_ref, &ref); + EXPECT_ERR(err); + + /* + * The stack length should grow continuously for all runs where + * auto compaction is disabled. When enabled, we should merge + * all tables in the stack. + */ + if (i != n) + EXPECT(st->merged->stack_len == i + 1); + else + EXPECT(st->merged->stack_len == 1);
You could shorten this to
EXPECT(st->merged->stack_len == (i == n ? 1 : i + 1);
But I like the version that you wrote here better, because it clearly
indicates when we should and should not perform compaction.
Thanks,
Taylor