Re: [PATCH 5/5] t-reftable-readwrite: add tests for print functions

On Thu, 8 Aug 2024 at 17:36, Patrick Steinhardt [off-list ref] wrote:

On Thu, Aug 08, 2024 at 10:12:07AM +0200, Patrick Steinhardt wrote:

quoted

On Wed, Aug 07, 2024 at 07:42:01PM +0530, Chandra Pratap wrote:

quoted

+static void t_table_print(void)
+{
+   char name[100];
+   struct reftable_write_options opts = {
+           .block_size = 512,
+           .hash_id = GIT_SHA1_FORMAT_ID,
+   };
+   struct reftable_ref_record ref = { 0 };
+   struct reftable_log_record log = { 0 };
+   struct reftable_writer *w = NULL;
+   struct tempfile *tmp = NULL;
+   size_t i, N = 3;
+   int n, fd;
+
+   xsnprintf(name, sizeof(name), "t-reftable-readwrite-%d-XXXXXX", __LINE__);

Is it really required to include the line number in this file? This
feels unnecessarily defensive to me as `mks_tempfile_t()` should already
make sure that we get a unique filename. So if we drop that, we could
skip this call to `xsnprintf()`.

quoted

+   tmp = mks_tempfile_t(name);
+   fd = get_tempfile_fd(tmp);
+   w = reftable_new_writer(&fd_write, &fd_flush, &fd, &opts);
+   reftable_writer_set_limits(w, 0, update_index);
+
+   for (i = 0; i < N; i++) {
+           xsnprintf(name, sizeof(name), "refs/heads/branch%02"PRIuMAX, (uintmax_t)i);
+           ref.refname = name;
+           ref.update_index = i;
+           ref.value_type = REFTABLE_REF_VAL1;
+           set_test_hash(ref.value.val1, i);
+
+           n = reftable_writer_add_ref(w, &ref);
+           check_int(n, ==, 0);
+   }
+
+   for (i = 0; i < N; i++) {
+           xsnprintf(name, sizeof(name), "refs/heads/branch%02"PRIuMAX, (uintmax_t)i);
+           log.refname = name;
+           log.update_index = i;
+           log.value_type = REFTABLE_LOG_UPDATE;
+           set_test_hash(log.value.update.new_hash, i);
+           log.value.update.name = (char *) "John Doe";
+           log.value.update.email = (char *) "johndoe@anon.org";
+           log.value.update.time = 0x6673e5b9;
+           log.value.update.message = (char *) "message";
+
+           n = reftable_writer_add_log(w, &log);
+           check_int(n, ==, 0);
+   }
+
+   n = reftable_writer_close(w);
+   check_int(n, ==, 0);
+
+   test_msg("testing printing functionality:");

Is it intentionally that this line still exists? If so, I think it
really only causes unnecessary noise and should rather be dropped.

quoted

+   n = reftable_reader_print_file(tmp->filename.buf);
+   check_int(n, ==, 0);

Wait, doesn't this print to stdout? I don't think it is a good idea to
exercise the function as-is. For one, it would pollute stdout with data
that we shouldn't care about. Second, it doesn't verify that the result
is actually what we expect.

I can see two options:

  1. Refactor these interfaces such that they take a file descriptor as
     input that they are writing to. This would allow us to exercise
     that the output is correct.

  2. Rip out this function. I don't think this functionality should be
     part of the library in the first place, and it really only exists
     because of "reftable/dump.c".

I think the latter is the better option. The functionality exists to
drive `cmd__dump_reftable()` in our reftable test helper. We should
likely make the whole implementation of this an internal implementation
detail and not expose it.

For the record: I've got a bigger patch series in development that drops
the generic reftable interfaces. As part of this, I'll also rip out the
functionality provided by "reftabel/dump.c".

Cool, I'll just drop this patch from the series then.