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_to_hex_algop 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).

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

@@ -1346,6 +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/unit-tests/t-hash.c

@@ -0,0 +1,120 @@
+#include "test-lib.h"
+#include "hash-ll.h"
+#include "hex.h"
+#include "strbuf.h"
+
+static const char out_file[] = "./output.txt";
+static const char *aaaaaaaaaa_100000;
+static const char *alphabet_100000;
+
+static const char *repeat(const char *pattern, size_t repetitions) {
+	char *ptr;
+	char *result;
+	size_t pattern_len;
+	size_t total_length;
+
+    	pattern_len = strlen(pattern);
+    	total_length = pattern_len * repetitions;
+
+    	result = malloc(total_length + 1);
+    	if (!result) {
+		test_msg("Memory allocation failed\n");
+        	return NULL;
+    	}
+
+	ptr = result;
+    	for (size_t i = 0; i < repetitions; i++) {
+        	memcpy(ptr, pattern, pattern_len);
+        	ptr += pattern_len;
+    	}
+
+    	*ptr = '\0';
+
+   	 return result;
+}
+
+static void hash_impl(const char *av, int algo) {
+	git_hash_ctx ctx;
+	unsigned char hash[GIT_MAX_HEXSZ];
+	const struct git_hash_algo *algop = &hash_algos[algo];
+	FILE *file;
+	size_t data_length;
+
+	if (!av || !*av) {
+		test_msg("Error: No input provided");
+		return;
+	}
+
+	algop->init_fn(&ctx);
+
+	data_length = strlen(av);
+
+	algop->update_fn(&ctx, av, data_length);
+
+	algop->final_fn(hash, &ctx);
+
+	file = freopen(out_file, "w", stderr);
+	if (!check(!!file)) {
+		test_msg("Error opening file %s", out_file);
+		return;
+	}
+
+	fwrite(hash_to_hex_algop(hash, algop), 1, algop->rawsz * 2, file);
+
+	fclose(file);
+}
+
+#define TEST_SHA1(given, expected_output) \
+    	TEST(check_hash(given, expected_output, GIT_HASH_SHA1 ), \
+        	"SHA1 (%s) works", #given)
+
+#define TEST_SHA256(given, expected_output) \
+    	TEST(check_hash(given, expected_output, GIT_HASH_SHA256 ), \
+        	"SHA256 (%s) works", #given)
+
+static void check_hash(const char *input, const char *expected, int algo) {
+
+	struct strbuf actual = STRBUF_INIT;
+
+	hash_impl(input, algo);
+	if (!check(strbuf_read_file(&actual, out_file, 0) >= 0)) {
+		test_msg("Error reading file %s", out_file);
+		strbuf_release(&actual);
+		return;
+	}
+
+	check_str(actual.buf, expected);
+	strbuf_release(&actual);
+
+	if (!check(remove(out_file) == 0))
+		test_msg("Error deleting %s", out_file);
+}
+
+int cmd_main(int argc, const char **argv) {
+	setenv("LANG", "C", 1);
+	aaaaaaaaaa_100000 = repeat("aaaaaaaaaa", 100000);
+	alphabet_100000 = repeat("abcdefghijklmnopqrstuvwxyz", 100000);
+
+	TEST_SHA1(NULL, "da39a3ee5e6b4b0d3255bfef95601890afd80709");
+	TEST_SHA1("a", "86f7e437faa5a7fce15d1ddcb9eaeaea377667b8");
+	TEST_SHA1("abc", "a9993e364706816aba3e25717850c26c9cd0d89d");
+	TEST_SHA1("message digest", "c12252ceda8be8994d5fa0290a47231c1d16aae3");
+	TEST_SHA1("abcdefghijklmnopqrstuvwxyz", "32d10c7b8cf96570ca04ce37f2a19d84240d3a89");
+	TEST_SHA1(aaaaaaaaaa_100000, "34aa973cd4c4daa4f61eeb2bdbad27316534016f");
+	TEST_SHA1("blob 0\0", "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391");
+	TEST_SHA1("blob 3\0abc", "f2ba8f84ab5c1bce84a7b441cb1959cfc7093b7f");
+	TEST_SHA1("tree 0\0", "4b825dc642cb6eb9a060e54bf8d69288fbee4904");
+
+	TEST_SHA256("", "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855");
+	TEST_SHA256("a", "ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb");
+	TEST_SHA256("abc", "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad");
+	TEST_SHA256("message digest", "f7846f55cf23e14eebeab5b4e1550cad5b509e3348fbc4efa3a1413d393cb650");
+	TEST_SHA256("abcdefghijklmnopqrstuvwxyz", "71c480df93d6ae2f1efad1447c66c9525e316218cf51fc8d9ed832f2daf18b73");
+	TEST_SHA256(aaaaaaaaaa_100000, "cdc76e5c9914fb9281a1c7e284d73e67f1809a48a497200e046d39ccc7112cd0");
+	TEST_SHA256(alphabet_100000, "e406ba321ca712ad35a698bf0af8d61fc4dc40eca6bdcea4697962724ccbde35");
+	TEST_SHA256("blob 0\0", "473a0f4c3be8a93681a267e3b1e9a7dcda1185436fe141f7749120a303721813");
+	TEST_SHA256("blob 3\0abc", "c1cf6e465077930e88dc5136641d402f72a229ddd996f627d60e9639eaba35a6");
+	TEST_SHA256("tree 0\0", "6ef19b41225c5369f1c104d45d8d85efa9b057b53b14b4b9b939dd74decc5321");
+
+	return test_done();
+}