Port helper/test-sha256.c and helper/test-sha1.c to unit-tests/t-hash.c

In the recent codebase update (8bf6fbd (Merge branch
'js/doc-unit-tests', 2023-12-09)), a new unit testing framework was
merged, providing a standardized approach for testing C code. Prior to
this update, some unit tests relied on the test helper mechanism,
lacking a dedicated unit testing framework. It's more natural to perform
these unit tests using the new unit test framework.

This commit migrates the unit tests for hash functionality from the
legacy approach using the test-tool command `test-tool sha1`and
`test-tool sha256` in helper/test-sha256.c and helper/test-sha1.c to the
new unit testing framework (t/unit-tests/test-lib.h). Porting
t0013-sha1dc.sh is left for later.

The migration involves refactoring the tests to utilize the testing
macros provided by the framework (TEST() and check_*()).

Mentored-by: Christian Couder <[email protected]>
Signed-off-by: Achu Luma <[email protected]>

Makefile

@@ -847,7 +847,6 @@ TEST_BUILTINS_OBJS += test-run-command.o
 TEST_BUILTINS_OBJS += test-scrap-cache-tree.o
 TEST_BUILTINS_OBJS += test-serve-v2.o
 TEST_BUILTINS_OBJS += test-sha1.o
-TEST_BUILTINS_OBJS += test-sha256.o
 TEST_BUILTINS_OBJS += test-sigchain.o
 TEST_BUILTINS_OBJS += test-simple-ipc.o
 TEST_BUILTINS_OBJS += test-strcmp-offset.o
@@ -1347,6 +1346,7 @@ UNIT_TEST_PROGRAMS += t-mem-pool
 UNIT_TEST_PROGRAMS += t-strbuf
 UNIT_TEST_PROGRAMS += t-ctype
 UNIT_TEST_PROGRAMS += t-prio-queue
+UNIT_TEST_PROGRAMS += t-hash
 UNIT_TEST_PROGS = $(patsubst %,$(UNIT_TEST_BIN)/%$X,$(UNIT_TEST_PROGRAMS))
 UNIT_TEST_OBJS = $(patsubst %,$(UNIT_TEST_DIR)/%.o,$(UNIT_TEST_PROGRAMS))
 UNIT_TEST_OBJS += $(UNIT_TEST_DIR)/test-lib.o

t/helper/test-tool.c

@@ -73,7 +73,6 @@ static struct test_cmd cmds[] = {
 	{ "serve-v2", cmd__serve_v2 },
 	{ "sha1", cmd__sha1 },
 	{ "sha1-is-sha1dc", cmd__sha1_is_sha1dc },
-	{ "sha256", cmd__sha256 },
 	{ "sigchain", cmd__sigchain },
 	{ "simple-ipc", cmd__simple_ipc },
 	{ "strcmp-offset", cmd__strcmp_offset },

t/helper/test-tool.h

@@ -66,7 +66,6 @@ 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);
 int cmd__strcmp_offset(int argc, const char **argv);

t/unit-tests/t-hash.c

@@ -0,0 +1,75 @@
+#include "test-lib.h"
+#include "hash-ll.h"
+#include "hex.h"
+#include "strbuf.h"
+
+static void check_hash_data(const void *data, size_t data_length, const char *expected, int algo) {
+	git_hash_ctx ctx;
+	unsigned char hash[GIT_MAX_HEXSZ];
+	const struct git_hash_algo *algop = &hash_algos[algo];
+
+	if (!check(!!data)) {
+    		test_msg("Error: No data provided when expecting: %s", expected);
+    		return;
+	}
+
+	algop->init_fn(&ctx);
+	algop->update_fn(&ctx, data, data_length);
+	algop->final_fn(hash, &ctx);
+
+	check_str(hash_to_hex_algop(hash, algop), expected);
+}
+
+/* Works with a NUL terminated string. Doesn't work if it should contain a NUL character. */
+#define TEST_SHA1_STR(data, expected) \
+    	TEST(check_hash_data(data, strlen(data), expected, GIT_HASH_SHA1), \
+        	"SHA1 (%s) works", #data)
+
+/* Only works with a literal string, useful when it contains a NUL character. */
+#define TEST_SHA1_LITERAL(literal, expected) \
+    	TEST(check_hash_data(literal, (sizeof(literal) - 1), expected, GIT_HASH_SHA1), \
+        	"SHA1 (%s) works", #literal)
+
+/* Works with a NUL terminated string. Doesn't work if it should contain a NUL character. */
+#define TEST_SHA256_STR(data, expected) \
+    	TEST(check_hash_data(data, strlen(data), expected, GIT_HASH_SHA256), \
+        	"SHA256 (%s) works", #data)
+
+/* Only works with a literal string, useful when it contains a NUL character. */
+#define TEST_SHA256_LITERAL(literal, expected) \
+    	TEST(check_hash_data(literal, (sizeof(literal) - 1), expected, GIT_HASH_SHA256), \
+        	"SHA256 (%s) works", #literal)
+
+int cmd_main(int argc, const char **argv) {
+	struct strbuf aaaaaaaaaa_100000 = STRBUF_INIT;
+	struct strbuf alphabet_100000 = STRBUF_INIT;
+
+	strbuf_addstrings(&aaaaaaaaaa_100000, "aaaaaaaaaa", 100000);
+	strbuf_addstrings(&alphabet_100000, "abcdefghijklmnopqrstuvwxyz", 100000);
+
+	TEST_SHA1_STR("", "da39a3ee5e6b4b0d3255bfef95601890afd80709");
+	TEST_SHA1_STR("a", "86f7e437faa5a7fce15d1ddcb9eaeaea377667b8");
+	TEST_SHA1_STR("abc", "a9993e364706816aba3e25717850c26c9cd0d89d");
+	TEST_SHA1_STR("message digest", "c12252ceda8be8994d5fa0290a47231c1d16aae3");
+	TEST_SHA1_STR("abcdefghijklmnopqrstuvwxyz", "32d10c7b8cf96570ca04ce37f2a19d84240d3a89");
+	TEST_SHA1_STR(aaaaaaaaaa_100000.buf, "34aa973cd4c4daa4f61eeb2bdbad27316534016f");
+	TEST_SHA1_LITERAL("blob 0\0", "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391");
+	TEST_SHA1_LITERAL("blob 3\0abc", "f2ba8f84ab5c1bce84a7b441cb1959cfc7093b7f");
+	TEST_SHA1_LITERAL("tree 0\0", "4b825dc642cb6eb9a060e54bf8d69288fbee4904");
+
+	TEST_SHA256_STR("", "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855");
+	TEST_SHA256_STR("a", "ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb");
+	TEST_SHA256_STR("abc", "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad");
+	TEST_SHA256_STR("message digest", "f7846f55cf23e14eebeab5b4e1550cad5b509e3348fbc4efa3a1413d393cb650");
+	TEST_SHA256_STR("abcdefghijklmnopqrstuvwxyz", "71c480df93d6ae2f1efad1447c66c9525e316218cf51fc8d9ed832f2daf18b73");
+	TEST_SHA256_STR(aaaaaaaaaa_100000.buf, "cdc76e5c9914fb9281a1c7e284d73e67f1809a48a497200e046d39ccc7112cd0");
+	TEST_SHA256_STR(alphabet_100000.buf, "e406ba321ca712ad35a698bf0af8d61fc4dc40eca6bdcea4697962724ccbde35");
+	TEST_SHA256_LITERAL("blob 0\0", "473a0f4c3be8a93681a267e3b1e9a7dcda1185436fe141f7749120a303721813");
+	TEST_SHA256_LITERAL("blob 3\0abc", "c1cf6e465077930e88dc5136641d402f72a229ddd996f627d60e9639eaba35a6");
+	TEST_SHA256_LITERAL("tree 0\0", "6ef19b41225c5369f1c104d45d8d85efa9b057b53b14b4b9b939dd74decc5321");
+
+	strbuf_release(&aaaaaaaaaa_100000);
+	strbuf_release(&alphabet_100000);
+
+	return test_done();
+}