diff mbox series

[GSoC,v3] t: port helper/test-oid-array.c to unit-tests/t-oid-array.c

Message ID 20240824170223.36080-1-shyamthakkar001@gmail.com (mailing list archive)
State Superseded
Headers show
Series [GSoC,v3] t: port helper/test-oid-array.c to unit-tests/t-oid-array.c | expand

Commit Message

Ghanshyam Thakkar Aug. 24, 2024, 5:02 p.m. UTC
helper/test-oid-array.c along with t0064-oid-array.sh test the
oid-array.h API, which provides storage and processing
efficiency over large lists of object identifiers.

Migrate them to the unit testing framework for better runtime
performance and efficiency. Also 'the_hash_algo' is used internally in
oid_array_lookup(), but we do not initialize a repository directory,
therefore initialize the_hash_algo manually. And
init_hash_algo():lib-oid.c can aid in this process, so make it public.

Mentored-by: Christian Couder <chriscool@tuxfamily.org>
Mentored-by: Kaartic Sivaraam <kaartic.sivaraam@gmail.com>
Helped-by: Phillip Wood <phillip.wood123@gmail.com>
Signed-off-by: Ghanshyam Thakkar <shyamthakkar001@gmail.com>
---
Changes in v3:
 - changed commmit message and comments for more accurate description
 - removed test_min() and return early when actual.nr and expect.nr
   don't match
 - rename result to expect for more accurate description
 - removed a redundant check in t_enumeration()
 - add check_int() around one of calls of get_oid_arbitrary_hex()
 - rebased to latest master

 Makefile                   |   2 +-
 t/helper/test-oid-array.c  |  49 ---------------
 t/helper/test-tool.c       |   1 -
 t/helper/test-tool.h       |   1 -
 t/t0064-oid-array.sh       | 122 -----------------------------------
 t/unit-tests/lib-oid.c     |   2 +-
 t/unit-tests/lib-oid.h     |   8 +++
 t/unit-tests/t-oid-array.c | 126 +++++++++++++++++++++++++++++++++++++
 8 files changed, 136 insertions(+), 175 deletions(-)
 delete mode 100644 t/helper/test-oid-array.c
 delete mode 100755 t/t0064-oid-array.sh
 create mode 100644 t/unit-tests/t-oid-array.c


Range-diff against v2:
1:  27124bbb00 ! 1:  408a179736 t: port helper/test-oid-array.c to unit-tests/t-oid-array.c
    @@ Commit message
         t: port helper/test-oid-array.c to unit-tests/t-oid-array.c
     
         helper/test-oid-array.c along with t0064-oid-array.sh test the
    -    oid-array.h library, which provides storage and processing
    +    oid-array.h API, which provides storage and processing
         efficiency over large lists of object identifiers.
     
         Migrate them to the unit testing framework for better runtime
    @@ Makefile: TEST_BUILTINS_OBJS += test-lazy-init-name-hash.o
      TEST_BUILTINS_OBJS += test-online-cpus.o
      TEST_BUILTINS_OBJS += test-pack-mtimes.o
      TEST_BUILTINS_OBJS += test-parse-options.o
    -@@ Makefile: UNIT_TEST_PROGRAMS += t-ctype
    - UNIT_TEST_PROGRAMS += t-example-decorate
    +@@ Makefile: UNIT_TEST_PROGRAMS += t-example-decorate
      UNIT_TEST_PROGRAMS += t-hash
    + UNIT_TEST_PROGRAMS += t-hashmap
      UNIT_TEST_PROGRAMS += t-mem-pool
     +UNIT_TEST_PROGRAMS += t-oid-array
      UNIT_TEST_PROGRAMS += t-oidmap
    @@ t/unit-tests/lib-oid.h
      int get_oid_arbitrary_hex(const char *s, struct object_id *oid);
     +/*
     + * Returns one of GIT_HASH_{SHA1, SHA256, UNKNOWN} based on the value of
    -+ * GIT_TEST_DEFAULT_HASH. The fallback value in case of absence of
    -+ * GIT_TEST_DEFAULT_HASH is GIT_HASH_SHA1.
    ++ * GIT_TEST_DEFAULT_HASH environment variable. The fallback value in case
    ++ * of absence of GIT_TEST_DEFAULT_HASH is GIT_HASH_SHA1. It also uses
    ++ * check(algo != GIT_HASH_UNKNOWN) before returning to verify if the
    ++ * GIT_TEST_DEFAULT_HASH's value is valid or not.
     + */
     +int init_hash_algo(void);
      
    @@ t/unit-tests/t-oid-array.c (new)
     +#include "oid-array.h"
     +#include "hex.h"
     +
    -+static inline size_t test_min(size_t a, size_t b)
    -+{
    -+	return a <= b ? a : b;
    -+}
    -+
     +static int fill_array(struct oid_array *array, const char *hexes[], size_t n)
     +{
     +	for (size_t i = 0; i < n; i++) {
    @@ t/unit-tests/t-oid-array.c (new)
     +}
     +
     +static void t_enumeration(const char **input_args, size_t input_sz,
    -+			  const char **result, size_t result_sz)
    ++			  const char **expect_args, size_t expect_sz)
     +{
     +	struct oid_array input = OID_ARRAY_INIT, expect = OID_ARRAY_INIT,
     +			 actual = OID_ARRAY_INIT;
    @@ t/unit-tests/t-oid-array.c (new)
     +
     +	if (fill_array(&input, input_args, input_sz))
     +		return;
    -+	if (fill_array(&expect, result, result_sz))
    ++	if (fill_array(&expect, expect_args, expect_sz))
     +		return;
     +
     +	oid_array_for_each_unique(&input, add_to_oid_array, &actual);
    -+	check_uint(actual.nr, ==, expect.nr);
    ++	if(!check_uint(actual.nr, ==, expect.nr))
    ++		return;
     +
    -+	for (i = 0; i < test_min(actual.nr, expect.nr); i++) {
    ++	for (i = 0; i < actual.nr; i++) {
     +		if (!check(oideq(&actual.oid[i], &expect.oid[i])))
     +			test_msg("expected: %s\n       got: %s\n     index: %" PRIuMAX,
     +				 oid_to_hex(&expect.oid[i]), oid_to_hex(&actual.oid[i]),
     +				 (uintmax_t)i);
     +	}
    -+	check_uint(i, ==, result_sz);
     +
     +	oid_array_clear(&actual);
     +	oid_array_clear(&input);
     +	oid_array_clear(&expect);
     +}
     +
    -+#define TEST_ENUMERATION(input, result, desc)                                     \
    -+	TEST(t_enumeration(input, ARRAY_SIZE(input), result, ARRAY_SIZE(result)), \
    ++#define TEST_ENUMERATION(input, expect, desc)                                     \
    ++	TEST(t_enumeration(input, ARRAY_SIZE(input), expect, ARRAY_SIZE(expect)), \
     +			   desc " works")
     +
     +static void t_lookup(const char **input_hexes, size_t n, const char *query_hex,
    @@ t/unit-tests/t-oid-array.c (new)
     +	struct object_id oid_query;
     +	int ret;
     +
    -+	if (get_oid_arbitrary_hex(query_hex, &oid_query))
    ++	if (!check_int(get_oid_arbitrary_hex(query_hex, &oid_query), ==, 0))
     +		return;
     +	if (fill_array(&array, input_hexes, n))
     +		return;
    @@ t/unit-tests/t-oid-array.c (new)
     +
     +static void setup(void)
     +{
    ++	/* The hash algo is used by oid_array_lookup() internally */
     +	int algo = init_hash_algo();
    -+	/* because the_hash_algo is used by oid_array_lookup() internally */
     +	if (check_int(algo, !=, GIT_HASH_UNKNOWN))
     +		repo_set_hash_algo(the_repository, algo);
     +}
    @@ t/unit-tests/t-oid-array.c (new)
     +	TEST_ENUMERATION(arr_input_dup, res_sorted,
     +			 "ordered enumeration with duplicate suppression");
     +
    -+	/* ret is the return value of oid_array_lookup() */
     +	TEST_LOOKUP(arr_input, "55", 1, 1, "lookup");
     +	TEST_LOOKUP(arr_input, "33", INT_MIN, -1, "lookup non-existent entry");
     +	TEST_LOOKUP(arr_input_dup, "55", 3, 5, "lookup with duplicates");

Comments

Christian Couder Aug. 25, 2024, 6:38 a.m. UTC | #1
On Sat, Aug 24, 2024 at 7:02 PM Ghanshyam Thakkar
<shyamthakkar001@gmail.com> wrote:
>
> helper/test-oid-array.c along with t0064-oid-array.sh test the
> oid-array.h API, which provides storage and processing
> efficiency over large lists of object identifiers.
>
> Migrate them to the unit testing framework for better runtime
> performance and efficiency. Also 'the_hash_algo' is used internally in
> oid_array_lookup(), but we do not initialize a repository directory,
> therefore initialize the_hash_algo manually.

Even if 'the_hash_algo' is used internally in oid_array_lookup()
through oid_pos(), this patch initializes the hash algo for the repo
using repo_set_hash_algo(), which contains the following single
instruction:

    repo->hash_algo = &hash_algos[hash_algo];

So "therefore initialize the_hash_algo manually" is not quite true, as
it doesn't look like 'the_hash_algo' is even used.

Also I think it's not clear how initializing a repository directory is
related to the hash algo.

So maybe something like the following would be better:

"As we don't initialize a repository in these tests, the hash algo
that functions like oid_array_lookup() use is not initialized,
therefore call repo_set_hash_algo() to initialize it."

> And
> init_hash_algo():lib-oid.c can aid in this process, so make it public.
>
> Mentored-by: Christian Couder <chriscool@tuxfamily.org>
> Mentored-by: Kaartic Sivaraam <kaartic.sivaraam@gmail.com>
> Helped-by: Phillip Wood <phillip.wood123@gmail.com>
> Signed-off-by: Ghanshyam Thakkar <shyamthakkar001@gmail.com>
> ---
> Changes in v3:
>  - changed commmit message and comments for more accurate description
>  - removed test_min() and return early when actual.nr and expect.nr
>    don't match
>  - rename result to expect for more accurate description
>  - removed a redundant check in t_enumeration()
>  - add check_int() around one of calls of get_oid_arbitrary_hex()

This looks good.

>  - rebased to latest master

It's nice to say it was rebased, but it's better to tell the reason
why it was rebased.

> diff --git a/t/unit-tests/lib-oid.h b/t/unit-tests/lib-oid.h
> index 8d2acca768..c949af082c 100644
> --- a/t/unit-tests/lib-oid.h
> +++ b/t/unit-tests/lib-oid.h
> @@ -13,5 +13,13 @@
>   * environment variable.
>   */
>  int get_oid_arbitrary_hex(const char *s, struct object_id *oid);
> +/*
> + * Returns one of GIT_HASH_{SHA1, SHA256, UNKNOWN} based on the value of
> + * GIT_TEST_DEFAULT_HASH environment variable. The fallback value in case
> + * of absence of GIT_TEST_DEFAULT_HASH is GIT_HASH_SHA1. It also uses

Nit: maybe: s/in case of absence/in the absence/

> + * check(algo != GIT_HASH_UNKNOWN) before returning to verify if the
> + * GIT_TEST_DEFAULT_HASH's value is valid or not.
> + */
> +int init_hash_algo(void);

[...]

> +static void t_enumeration(const char **input_args, size_t input_sz,
> +                         const char **expect_args, size_t expect_sz)
> +{
> +       struct oid_array input = OID_ARRAY_INIT, expect = OID_ARRAY_INIT,
> +                        actual = OID_ARRAY_INIT;
> +       size_t i;
> +
> +       if (fill_array(&input, input_args, input_sz))
> +               return;
> +       if (fill_array(&expect, expect_args, expect_sz))
> +               return;
> +
> +       oid_array_for_each_unique(&input, add_to_oid_array, &actual);
> +       if(!check_uint(actual.nr, ==, expect.nr))

Missing space between 'if' and '('.

> +               return;

The rest of the patch looks good to me. Thanks.
Ghanshyam Thakkar Aug. 25, 2024, 10:45 a.m. UTC | #2
Christian Couder <christian.couder@gmail.com> wrote:
> On Sat, Aug 24, 2024 at 7:02 PM Ghanshyam Thakkar
> <shyamthakkar001@gmail.com> wrote:
> >
> > helper/test-oid-array.c along with t0064-oid-array.sh test the
> > oid-array.h API, which provides storage and processing
> > efficiency over large lists of object identifiers.
> >
> > Migrate them to the unit testing framework for better runtime
> > performance and efficiency. Also 'the_hash_algo' is used internally in
> > oid_array_lookup(), but we do not initialize a repository directory,
> > therefore initialize the_hash_algo manually.
>
> Even if 'the_hash_algo' is used internally in oid_array_lookup()
> through oid_pos(), this patch initializes the hash algo for the repo
> using repo_set_hash_algo(), which contains the following single
> instruction:
>
> repo->hash_algo = &hash_algos[hash_algo];
>
> So "therefore initialize the_hash_algo manually" is not quite true, as
> it doesn't look like 'the_hash_algo' is even used.

the_hash_algo is just:
    define the_hash_algo the_repository->hash_algo

and we do initialize the_repository->hash_algo manually.

>
> Also I think it's not clear how initializing a repository directory is
> related to the hash algo.

That is mentioned because the old code in helper/test-oid-array.c used
to call setup_git_directory_gently() to setup a git directory, which
would also initialize the_repository->hash_algo.

>
> So maybe something like the following would be better:
>
> "As we don't initialize a repository in these tests, the hash algo
> that functions like oid_array_lookup() use is not initialized,
> therefore call repo_set_hash_algo() to initialize it."

Will change.

>
> > And
> > init_hash_algo():lib-oid.c can aid in this process, so make it public.
> >
> > Mentored-by: Christian Couder <chriscool@tuxfamily.org>
> > Mentored-by: Kaartic Sivaraam <kaartic.sivaraam@gmail.com>
> > Helped-by: Phillip Wood <phillip.wood123@gmail.com>
> > Signed-off-by: Ghanshyam Thakkar <shyamthakkar001@gmail.com>
> > ---
> > Changes in v3:
> >  - changed commmit message and comments for more accurate description
> >  - removed test_min() and return early when actual.nr and expect.nr
> >    don't match
> >  - rename result to expect for more accurate description
> >  - removed a redundant check in t_enumeration()
> >  - add check_int() around one of calls of get_oid_arbitrary_hex()
>
> This looks good.
>
> >  - rebased to latest master
>
> It's nice to say it was rebased, but it's better to tell the reason
> why it was rebased.

No particular reason other than the fact that v2 was posted 20 days ago.
And it is not merged into 'seen' or 'next', so it shouldn't be a
problem.

Thanks.
diff mbox series

Patch

diff --git a/Makefile b/Makefile
index e298c8b55e..8813753d99 100644
--- a/Makefile
+++ b/Makefile
@@ -808,7 +808,6 @@  TEST_BUILTINS_OBJS += test-lazy-init-name-hash.o
 TEST_BUILTINS_OBJS += test-match-trees.o
 TEST_BUILTINS_OBJS += test-mergesort.o
 TEST_BUILTINS_OBJS += test-mktemp.o
-TEST_BUILTINS_OBJS += test-oid-array.o
 TEST_BUILTINS_OBJS += test-online-cpus.o
 TEST_BUILTINS_OBJS += test-pack-mtimes.o
 TEST_BUILTINS_OBJS += test-parse-options.o
@@ -1337,6 +1336,7 @@  UNIT_TEST_PROGRAMS += t-example-decorate
 UNIT_TEST_PROGRAMS += t-hash
 UNIT_TEST_PROGRAMS += t-hashmap
 UNIT_TEST_PROGRAMS += t-mem-pool
+UNIT_TEST_PROGRAMS += t-oid-array
 UNIT_TEST_PROGRAMS += t-oidmap
 UNIT_TEST_PROGRAMS += t-oidtree
 UNIT_TEST_PROGRAMS += t-prio-queue
diff --git a/t/helper/test-oid-array.c b/t/helper/test-oid-array.c
deleted file mode 100644
index 076b849cbf..0000000000
--- a/t/helper/test-oid-array.c
+++ /dev/null
@@ -1,49 +0,0 @@ 
-#define USE_THE_REPOSITORY_VARIABLE
-
-#include "test-tool.h"
-#include "hex.h"
-#include "oid-array.h"
-#include "setup.h"
-#include "strbuf.h"
-
-static int print_oid(const struct object_id *oid, void *data UNUSED)
-{
-	puts(oid_to_hex(oid));
-	return 0;
-}
-
-int cmd__oid_array(int argc UNUSED, const char **argv UNUSED)
-{
-	struct oid_array array = OID_ARRAY_INIT;
-	struct strbuf line = STRBUF_INIT;
-	int nongit_ok;
-
-	setup_git_directory_gently(&nongit_ok);
-	if (nongit_ok)
-		repo_set_hash_algo(the_repository, GIT_HASH_SHA1);
-
-	while (strbuf_getline(&line, stdin) != EOF) {
-		const char *arg;
-		struct object_id oid;
-
-		if (skip_prefix(line.buf, "append ", &arg)) {
-			if (get_oid_hex(arg, &oid))
-				die("not a hexadecimal oid: %s", arg);
-			oid_array_append(&array, &oid);
-		} else if (skip_prefix(line.buf, "lookup ", &arg)) {
-			if (get_oid_hex(arg, &oid))
-				die("not a hexadecimal oid: %s", arg);
-			printf("%d\n", oid_array_lookup(&array, &oid));
-		} else if (!strcmp(line.buf, "clear"))
-			oid_array_clear(&array);
-		else if (!strcmp(line.buf, "for_each_unique"))
-			oid_array_for_each_unique(&array, print_oid, NULL);
-		else
-			die("unknown command: %s", line.buf);
-	}
-
-	strbuf_release(&line);
-	oid_array_clear(&array);
-
-	return 0;
-}
diff --git a/t/helper/test-tool.c b/t/helper/test-tool.c
index da3e69128a..353d2aaaa4 100644
--- a/t/helper/test-tool.c
+++ b/t/helper/test-tool.c
@@ -43,7 +43,6 @@  static struct test_cmd cmds[] = {
 	{ "match-trees", cmd__match_trees },
 	{ "mergesort", cmd__mergesort },
 	{ "mktemp", cmd__mktemp },
-	{ "oid-array", cmd__oid_array },
 	{ "online-cpus", cmd__online_cpus },
 	{ "pack-mtimes", cmd__pack_mtimes },
 	{ "parse-options", cmd__parse_options },
diff --git a/t/helper/test-tool.h b/t/helper/test-tool.h
index 642a34578c..d3d8aa28e0 100644
--- a/t/helper/test-tool.h
+++ b/t/helper/test-tool.h
@@ -64,7 +64,6 @@  int cmd__scrap_cache_tree(int argc, const char **argv);
 int cmd__serve_v2(int argc, const char **argv);
 int cmd__sha1(int argc, const char **argv);
 int cmd__sha1_is_sha1dc(int argc, const char **argv);
-int cmd__oid_array(int argc, const char **argv);
 int cmd__sha256(int argc, const char **argv);
 int cmd__sigchain(int argc, const char **argv);
 int cmd__simple_ipc(int argc, const char **argv);
diff --git a/t/t0064-oid-array.sh b/t/t0064-oid-array.sh
deleted file mode 100755
index de74b692d0..0000000000
--- a/t/t0064-oid-array.sh
+++ /dev/null
@@ -1,122 +0,0 @@ 
-#!/bin/sh
-
-test_description='basic tests for the oid array implementation'
-
-TEST_PASSES_SANITIZE_LEAK=true
-. ./test-lib.sh
-
-echoid () {
-	prefix="${1:+$1 }"
-	shift
-	while test $# -gt 0
-	do
-		echo "$prefix$ZERO_OID" | sed -e "s/00/$1/g"
-		shift
-	done
-}
-
-test_expect_success 'without repository' '
-	cat >expect <<-EOF &&
-	4444444444444444444444444444444444444444
-	5555555555555555555555555555555555555555
-	8888888888888888888888888888888888888888
-	aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-	EOF
-	cat >input <<-EOF &&
-	append 4444444444444444444444444444444444444444
-	append 5555555555555555555555555555555555555555
-	append 8888888888888888888888888888888888888888
-	append aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-	for_each_unique
-	EOF
-	nongit test-tool oid-array <input >actual &&
-	test_cmp expect actual
-'
-
-test_expect_success 'ordered enumeration' '
-	echoid "" 44 55 88 aa >expect &&
-	{
-		echoid append 88 44 aa 55 &&
-		echo for_each_unique
-	} | test-tool oid-array >actual &&
-	test_cmp expect actual
-'
-
-test_expect_success 'ordered enumeration with duplicate suppression' '
-	echoid "" 44 55 88 aa >expect &&
-	{
-		echoid append 88 44 aa 55 &&
-		echoid append 88 44 aa 55 &&
-		echoid append 88 44 aa 55 &&
-		echo for_each_unique
-	} | test-tool oid-array >actual &&
-	test_cmp expect actual
-'
-
-test_expect_success 'lookup' '
-	{
-		echoid append 88 44 aa 55 &&
-		echoid lookup 55
-	} | test-tool oid-array >actual &&
-	n=$(cat actual) &&
-	test "$n" -eq 1
-'
-
-test_expect_success 'lookup non-existing entry' '
-	{
-		echoid append 88 44 aa 55 &&
-		echoid lookup 33
-	} | test-tool oid-array >actual &&
-	n=$(cat actual) &&
-	test "$n" -lt 0
-'
-
-test_expect_success 'lookup with duplicates' '
-	{
-		echoid append 88 44 aa 55 &&
-		echoid append 88 44 aa 55 &&
-		echoid append 88 44 aa 55 &&
-		echoid lookup 55
-	} | test-tool oid-array >actual &&
-	n=$(cat actual) &&
-	test "$n" -ge 3 &&
-	test "$n" -le 5
-'
-
-test_expect_success 'lookup non-existing entry with duplicates' '
-	{
-		echoid append 88 44 aa 55 &&
-		echoid append 88 44 aa 55 &&
-		echoid append 88 44 aa 55 &&
-		echoid lookup 66
-	} | test-tool oid-array >actual &&
-	n=$(cat actual) &&
-	test "$n" -lt 0
-'
-
-test_expect_success 'lookup with almost duplicate values' '
-	# n-1 5s
-	root=$(echoid "" 55) &&
-	root=${root%5} &&
-	{
-		id1="${root}5" &&
-		id2="${root}f" &&
-		echo "append $id1" &&
-		echo "append $id2" &&
-		echoid lookup 55
-	} | test-tool oid-array >actual &&
-	n=$(cat actual) &&
-	test "$n" -eq 0
-'
-
-test_expect_success 'lookup with single duplicate value' '
-	{
-		echoid append 55 55 &&
-		echoid lookup 55
-	} | test-tool oid-array >actual &&
-	n=$(cat actual) &&
-	test "$n" -ge 0 &&
-	test "$n" -le 1
-'
-
-test_done
diff --git a/t/unit-tests/lib-oid.c b/t/unit-tests/lib-oid.c
index 37105f0a8f..8f0ccac532 100644
--- a/t/unit-tests/lib-oid.c
+++ b/t/unit-tests/lib-oid.c
@@ -3,7 +3,7 @@ 
 #include "strbuf.h"
 #include "hex.h"
 
-static int init_hash_algo(void)
+int init_hash_algo(void)
 {
 	static int algo = -1;
 
diff --git a/t/unit-tests/lib-oid.h b/t/unit-tests/lib-oid.h
index 8d2acca768..c949af082c 100644
--- a/t/unit-tests/lib-oid.h
+++ b/t/unit-tests/lib-oid.h
@@ -13,5 +13,13 @@ 
  * environment variable.
  */
 int get_oid_arbitrary_hex(const char *s, struct object_id *oid);
+/*
+ * Returns one of GIT_HASH_{SHA1, SHA256, UNKNOWN} based on the value of
+ * GIT_TEST_DEFAULT_HASH environment variable. The fallback value in case
+ * of absence of GIT_TEST_DEFAULT_HASH is GIT_HASH_SHA1. It also uses
+ * check(algo != GIT_HASH_UNKNOWN) before returning to verify if the
+ * GIT_TEST_DEFAULT_HASH's value is valid or not.
+ */
+int init_hash_algo(void);
 
 #endif /* LIB_OID_H */
diff --git a/t/unit-tests/t-oid-array.c b/t/unit-tests/t-oid-array.c
new file mode 100644
index 0000000000..99e3de9dc8
--- /dev/null
+++ b/t/unit-tests/t-oid-array.c
@@ -0,0 +1,126 @@ 
+#define USE_THE_REPOSITORY_VARIABLE
+
+#include "test-lib.h"
+#include "lib-oid.h"
+#include "oid-array.h"
+#include "hex.h"
+
+static int fill_array(struct oid_array *array, const char *hexes[], size_t n)
+{
+	for (size_t i = 0; i < n; i++) {
+		struct object_id oid;
+
+		if (!check_int(get_oid_arbitrary_hex(hexes[i], &oid), ==, 0))
+			return -1;
+		oid_array_append(array, &oid);
+	}
+	if (!check_uint(array->nr, ==, n))
+		return -1;
+	return 0;
+}
+
+static int add_to_oid_array(const struct object_id *oid, void *data)
+{
+	struct oid_array *array = data;
+
+	oid_array_append(array, oid);
+	return 0;
+}
+
+static void t_enumeration(const char **input_args, size_t input_sz,
+			  const char **expect_args, size_t expect_sz)
+{
+	struct oid_array input = OID_ARRAY_INIT, expect = OID_ARRAY_INIT,
+			 actual = OID_ARRAY_INIT;
+	size_t i;
+
+	if (fill_array(&input, input_args, input_sz))
+		return;
+	if (fill_array(&expect, expect_args, expect_sz))
+		return;
+
+	oid_array_for_each_unique(&input, add_to_oid_array, &actual);
+	if(!check_uint(actual.nr, ==, expect.nr))
+		return;
+
+	for (i = 0; i < actual.nr; i++) {
+		if (!check(oideq(&actual.oid[i], &expect.oid[i])))
+			test_msg("expected: %s\n       got: %s\n     index: %" PRIuMAX,
+				 oid_to_hex(&expect.oid[i]), oid_to_hex(&actual.oid[i]),
+				 (uintmax_t)i);
+	}
+
+	oid_array_clear(&actual);
+	oid_array_clear(&input);
+	oid_array_clear(&expect);
+}
+
+#define TEST_ENUMERATION(input, expect, desc)                                     \
+	TEST(t_enumeration(input, ARRAY_SIZE(input), expect, ARRAY_SIZE(expect)), \
+			   desc " works")
+
+static void t_lookup(const char **input_hexes, size_t n, const char *query_hex,
+		     int lower_bound, int upper_bound)
+{
+	struct oid_array array = OID_ARRAY_INIT;
+	struct object_id oid_query;
+	int ret;
+
+	if (!check_int(get_oid_arbitrary_hex(query_hex, &oid_query), ==, 0))
+		return;
+	if (fill_array(&array, input_hexes, n))
+		return;
+	ret = oid_array_lookup(&array, &oid_query);
+
+	if (!check_int(ret, <=, upper_bound) ||
+	    !check_int(ret, >=, lower_bound))
+		test_msg("oid query for lookup: %s", oid_to_hex(&oid_query));
+
+	oid_array_clear(&array);
+}
+
+#define TEST_LOOKUP(input_hexes, query, lower_bound, upper_bound, desc) \
+	TEST(t_lookup(input_hexes, ARRAY_SIZE(input_hexes), query,      \
+		      lower_bound, upper_bound),                        \
+	     desc " works")
+
+static void setup(void)
+{
+	/* The hash algo is used by oid_array_lookup() internally */
+	int algo = init_hash_algo();
+	if (check_int(algo, !=, GIT_HASH_UNKNOWN))
+		repo_set_hash_algo(the_repository, algo);
+}
+
+int cmd_main(int argc UNUSED, const char **argv UNUSED)
+{
+	const char *arr_input[] = { "88", "44", "aa", "55" };
+	const char *arr_input_dup[] = { "88", "44", "aa", "55",
+					"88", "44", "aa", "55",
+					"88", "44", "aa", "55" };
+	const char *res_sorted[] = { "44", "55", "88", "aa" };
+	const char *nearly_55;
+
+	if (!TEST(setup(), "setup"))
+		test_skip_all("hash algo initialization failed");
+
+	TEST_ENUMERATION(arr_input, res_sorted, "ordered enumeration");
+	TEST_ENUMERATION(arr_input_dup, res_sorted,
+			 "ordered enumeration with duplicate suppression");
+
+	TEST_LOOKUP(arr_input, "55", 1, 1, "lookup");
+	TEST_LOOKUP(arr_input, "33", INT_MIN, -1, "lookup non-existent entry");
+	TEST_LOOKUP(arr_input_dup, "55", 3, 5, "lookup with duplicates");
+	TEST_LOOKUP(arr_input_dup, "66", INT_MIN, -1,
+		    "lookup non-existent entry with duplicates");
+
+	nearly_55 = init_hash_algo() == GIT_HASH_SHA1 ?
+			"5500000000000000000000000000000000000001" :
+			"5500000000000000000000000000000000000000000000000000000000000001";
+	TEST_LOOKUP(((const char *[]){ "55", nearly_55 }), "55", 0, 0,
+		    "lookup with almost duplicate values");
+	TEST_LOOKUP(((const char *[]){ "55", "55" }), "55", 0, 1,
+		    "lookup with single duplicate value");
+
+	return test_done();
+}