[v6,7/7] t-reftable-pq: add tests for merged_iter_pqueue_top()

Commit Message

Chandra Pratap July 25, 2024, 9:25 a.m. UTC

merged_iter_pqueue_top() as defined by reftable/pq.{c, h} returns
the element at the top of a priority-queue's heap without removing
it. Since there are no tests for this function in the existing
setup, add tests for the same.

Mentored-by: Patrick Steinhardt <[e-mail]>
Mentored-by: Christian Couder <[e-mail]>
Signed-off-by: Chandra Pratap <[e-mail]>
---
 t/unit-tests/t-reftable-pq.c | 50 ++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)

Comments

Patrick Steinhardt July 30, 2024, 6:04 a.m. UTC | #1

On Thu, Jul 25, 2024 at 02:55:59PM +0530, Chandra Pratap wrote:
> @@ -95,10 +104,51 @@ static void t_pq_index(void)
>  	merged_iter_pqueue_release(&pq);
>  }
>  
> +static void t_merged_iter_pqueue_top(void)
> +{
> +	struct merged_iter_pqueue pq = { 0 };
> +	struct reftable_record recs[13];
> +	size_t N = ARRAY_SIZE(recs), i;
> +
> +	for (i = 0; i < N; i++) {
> +		reftable_record_init(&recs[i], BLOCK_TYPE_REF);
> +		recs[i].u.ref.refname = (char *) "refs/heads/master";
> +	}
> +
> +	i = 1;
> +	do {
> +		struct pq_entry e = {
> +			.rec = &recs[i],
> +			.index = i,
> +		};
> +
> +		merged_iter_pqueue_add(&pq, &e);
> +		merged_iter_pqueue_check(&pq);
> +		i = (i * 7) % N;
> +	}
> +	while (i != 1);

Same nit here. Other than that this patch series looks good to me,
thanks!

Patrick

Patch

diff --git a/t/unit-tests/t-reftable-pq.c b/t/unit-tests/t-reftable-pq.c
index 67f3e4546c..ce322d7255 100644
--- a/t/unit-tests/t-reftable-pq.c
+++ b/t/unit-tests/t-reftable-pq.c
@@ -18,6 +18,11 @@  static void merged_iter_pqueue_check(const struct merged_iter_pqueue *pq)
 	}
 }
 
+static int pq_entry_equal(struct pq_entry *a, struct pq_entry *b)
+{
+	return !reftable_record_cmp(a->rec, b->rec) && (a->index == b->index);
+}
+
 static void t_pq_record(void)
 {
 	struct merged_iter_pqueue pq = { 0 };
@@ -42,9 +47,11 @@  static void t_pq_record(void)
 	} while (i != 1);
 
 	while (!merged_iter_pqueue_is_empty(pq)) {
+		struct pq_entry top = merged_iter_pqueue_top(pq);
 		struct pq_entry e = merged_iter_pqueue_remove(&pq);
 		merged_iter_pqueue_check(&pq);
 
+		check(pq_entry_equal(&top, &e));
 		check(reftable_record_type(e.rec) == BLOCK_TYPE_REF);
 		if (last)
 			check_int(strcmp(last, e.rec->u.ref.refname), <, 0);
@@ -82,9 +89,11 @@  static void t_pq_index(void)
 	while (i != 1);
 
 	for (i = N - 1; i > 0; i--) {
+		struct pq_entry top = merged_iter_pqueue_top(pq);
 		struct pq_entry e = merged_iter_pqueue_remove(&pq);
 		merged_iter_pqueue_check(&pq);
 
+		check(pq_entry_equal(&top, &e));
 		check(reftable_record_type(e.rec) == BLOCK_TYPE_REF);
 		check_int(e.index, ==, i);
 		if (last)
@@ -95,10 +104,51 @@  static void t_pq_index(void)
 	merged_iter_pqueue_release(&pq);
 }
 
+static void t_merged_iter_pqueue_top(void)
+{
+	struct merged_iter_pqueue pq = { 0 };
+	struct reftable_record recs[13];
+	size_t N = ARRAY_SIZE(recs), i;
+
+	for (i = 0; i < N; i++) {
+		reftable_record_init(&recs[i], BLOCK_TYPE_REF);
+		recs[i].u.ref.refname = (char *) "refs/heads/master";
+	}
+
+	i = 1;
+	do {
+		struct pq_entry e = {
+			.rec = &recs[i],
+			.index = i,
+		};
+
+		merged_iter_pqueue_add(&pq, &e);
+		merged_iter_pqueue_check(&pq);
+		i = (i * 7) % N;
+	}
+	while (i != 1);
+
+	for (i = N - 1; i > 0; i--) {
+		struct pq_entry top = merged_iter_pqueue_top(pq);
+		struct pq_entry e = merged_iter_pqueue_remove(&pq);
+
+		merged_iter_pqueue_check(&pq);
+		check(pq_entry_equal(&top, &e));
+		check(reftable_record_equal(top.rec, &recs[i], GIT_SHA1_RAWSZ));
+		for (size_t j = 0; i < pq.len; j++) {
+			check(pq_less(&top, &pq.heap[j]));
+			check_int(top.index, >, j);
+		}
+	}
+
+	merged_iter_pqueue_release(&pq);
+}
+
 int cmd_main(int argc, const char *argv[])
 {
 	TEST(t_pq_record(), "pq works with record-based comparison");
 	TEST(t_pq_index(), "pq works with index-based comparison");
+	TEST(t_merged_iter_pqueue_top(), "merged_iter_pqueue_top works");
 
 	return test_done();
 }