t: migrate helper/test-oidmap.c to unit-tests/t-oidmap.c

helper/test-oidmap.c along with t0016-oidmap.sh test the oidmap.h
library which is built on top of hashmap.h.

Migrate them to the unit testing framework for better performance,
concise code and better debugging. Along with the migration also plug
memory leaks and make the test logic independent for all the tests.
The migration removes 'put' tests from t0016, because it is used as
setup to all the other tests, so testing it separately does not yield
any benefit.

Mentored-by: Christian Couder <[email protected]>
Mentored-by: Kaartic Sivaraam <[email protected]>
Reviewed-by: Josh Steadmon <[email protected]>
Helped-by: Phillip Wood <[email protected]>
Helped-by: Junio C Hamano <[email protected]>
Signed-off-by: Ghanshyam Thakkar <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Makefile

@@ -809,7 +809,6 @@ 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-oidmap.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-ctype
 UNIT_TEST_PROGRAMS += t-example-decorate
 UNIT_TEST_PROGRAMS += t-hash
 UNIT_TEST_PROGRAMS += t-mem-pool
+UNIT_TEST_PROGRAMS += t-oidmap
 UNIT_TEST_PROGRAMS += t-oidtree
 UNIT_TEST_PROGRAMS += t-prio-queue
 UNIT_TEST_PROGRAMS += t-reftable-basics

t/helper/test-tool.c

@@ -44,7 +44,6 @@ static struct test_cmd cmds[] = {
  { "mergesort", cmd__mergesort },
  { "mktemp", cmd__mktemp },
  { "oid-array", cmd__oid_array },
- { "oidmap", cmd__oidmap },
  { "online-cpus", cmd__online_cpus },
  { "pack-mtimes", cmd__pack_mtimes },
  { "parse-options", cmd__parse_options },

t/helper/test-tool.h

@@ -37,7 +37,6 @@ int cmd__lazy_init_name_hash(int argc, const char **argv);
 int cmd__match_trees(int argc, const char **argv);
 int cmd__mergesort(int argc, const char **argv);
 int cmd__mktemp(int argc, const char **argv);
-int cmd__oidmap(int argc, const char **argv);
 int cmd__online_cpus(int argc, const char **argv);
 int cmd__pack_mtimes(int argc, const char **argv);
 int cmd__parse_options(int argc, const char **argv);