t/unit-tests: adapt example decorate test to use clar test framework

Introduce `test_example_decorate__initialize()` to explicitly set up
object IDs and retrieve corresponding objects before tests run. This
ensures a consistent and predictable test state without relying on data
from previous tests.

Add `test_example_decorate__cleanup()` to clear decorations after each
test, preventing interference between tests and ensuring each runs in
isolation.

Adapt example decorate test script to clar framework by using clar
assertions where necessary. Previously, tests relied on data written by
earlier tests, leading to unintended dependencies between them. This
explicitly initializes the necessary state within
`test_example_decorate__readd`, ensuring it does not depend on prior
test executions.

Mentored-by: Patrick Steinhardt <[email protected]>
Signed-off-by: Seyi Kuforiji <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: Seyi007

Makefile

@@ -1340,6 +1340,7 @@ THIRD_PARTY_SOURCES += $(UNIT_TEST_DIR)/clar/%
 THIRD_PARTY_SOURCES += $(UNIT_TEST_DIR)/clar/clar/%
 
 CLAR_TEST_SUITES += u-ctype
+CLAR_TEST_SUITES += u-example-decorate
 CLAR_TEST_SUITES += u-hash
 CLAR_TEST_SUITES += u-hashmap
 CLAR_TEST_SUITES += u-mem-pool
@@ -1351,7 +1352,6 @@ CLAR_TEST_OBJS = $(patsubst %,$(UNIT_TEST_DIR)/%.o,$(CLAR_TEST_SUITES))
 CLAR_TEST_OBJS += $(UNIT_TEST_DIR)/clar/clar.o
 CLAR_TEST_OBJS += $(UNIT_TEST_DIR)/unit-test.o
 
-UNIT_TEST_PROGRAMS += t-example-decorate
 UNIT_TEST_PROGRAMS += t-oid-array
 UNIT_TEST_PROGRAMS += t-oidmap
 UNIT_TEST_PROGRAMS += t-oidtree

t/meson.build

@@ -1,5 +1,6 @@
 clar_test_suites = [
   'unit-tests/u-ctype.c',
+  'unit-tests/u-example-decorate.c',
   'unit-tests/u-hash.c',
   'unit-tests/u-hashmap.c',
   'unit-tests/u-mem-pool.c',
@@ -45,7 +46,6 @@ clar_unit_tests = executable('unit-tests',
 test('unit-tests', clar_unit_tests)
 
 unit_test_programs = [
-  'unit-tests/t-example-decorate.c',
   'unit-tests/t-oid-array.c',
   'unit-tests/t-oidmap.c',
   'unit-tests/t-oidtree.c',

t/unit-tests/t-example-decorate.c

@@ -0,0 +1,64 @@
+#define USE_THE_REPOSITORY_VARIABLE
+
+#include "unit-test.h"
+#include "object.h"
+#include "decorate.h"
+#include "repository.h"
+
+struct test_vars {
+	struct object *one, *two, *three;
+	struct decoration n;
+	int decoration_a, decoration_b;
+};
+
+static struct test_vars vars;
+
+void test_example_decorate__initialize(void)
+{
+	struct object_id one_oid = { { 1 } }, two_oid = { { 2 } }, three_oid = { { 3 } };
+
+	vars.one = lookup_unknown_object(the_repository, &one_oid);
+	vars.two = lookup_unknown_object(the_repository, &two_oid);
+	vars.three = lookup_unknown_object(the_repository, &three_oid);
+}
+
+void test_example_decorate__cleanup(void)
+{
+	clear_decoration(&vars.n, NULL);
+}
+
+void test_example_decorate__add(void)
+{
+	cl_assert_equal_p(add_decoration(&vars.n, vars.one, &vars.decoration_a), NULL);
+	cl_assert_equal_p(add_decoration(&vars.n, vars.two, NULL), NULL);
+}
+
+void test_example_decorate__readd(void)
+{
+	cl_assert_equal_p(add_decoration(&vars.n, vars.one, &vars.decoration_a), NULL);
+	cl_assert_equal_p(add_decoration(&vars.n, vars.two, NULL), NULL);
+	cl_assert_equal_p(add_decoration(&vars.n, vars.one, NULL), &vars.decoration_a);
+	cl_assert_equal_p(add_decoration(&vars.n, vars.two, &vars.decoration_b), NULL);
+}
+
+void test_example_decorate__lookup(void)
+{
+	cl_assert_equal_p(add_decoration(&vars.n, vars.two, &vars.decoration_b), NULL);
+	cl_assert_equal_p(add_decoration(&vars.n, vars.one, NULL), NULL);
+	cl_assert_equal_p(lookup_decoration(&vars.n, vars.two), &vars.decoration_b);
+	cl_assert_equal_p(lookup_decoration(&vars.n, vars.one), NULL);
+}
+
+void test_example_decorate__loop(void)
+{
+	int objects_noticed = 0;
+
+	cl_assert_equal_p(add_decoration(&vars.n, vars.one, &vars.decoration_a), NULL);
+	cl_assert_equal_p(add_decoration(&vars.n, vars.two, &vars.decoration_b), NULL);
+
+	for (size_t i = 0; i < vars.n.size; i++)
+		if (vars.n.entries[i].base)
+			objects_noticed++;
+
+	cl_assert_equal_i(objects_noticed, 2);
+}