t/unit-tests: convert strbuf test to use clar test framework

Adapt strbuf test script to clar framework by using clar assertions
where necessary.

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

Author: Seyi007

Makefile

@@ -1346,6 +1346,7 @@ CLAR_TEST_SUITES += u-hashmap
 CLAR_TEST_SUITES += u-mem-pool
 CLAR_TEST_SUITES += u-prio-queue
 CLAR_TEST_SUITES += u-reftable-tree
+CLAR_TEST_SUITES += u-strbuf
 CLAR_TEST_SUITES += u-strvec
 CLAR_TEST_PROG = $(UNIT_TEST_BIN)/unit-tests$(X)
 CLAR_TEST_OBJS = $(patsubst %,$(UNIT_TEST_DIR)/%.o,$(CLAR_TEST_SUITES))
@@ -1363,7 +1364,6 @@ UNIT_TEST_PROGRAMS += t-reftable-reader
 UNIT_TEST_PROGRAMS += t-reftable-readwrite
 UNIT_TEST_PROGRAMS += t-reftable-record
 UNIT_TEST_PROGRAMS += t-reftable-stack
-UNIT_TEST_PROGRAMS += t-strbuf
 UNIT_TEST_PROGRAMS += t-strcmp-offset
 UNIT_TEST_PROGRAMS += t-trailer
 UNIT_TEST_PROGRAMS += t-urlmatch-normalization

t/meson.build

@@ -6,6 +6,7 @@ clar_test_suites = [
   'unit-tests/u-mem-pool.c',
   'unit-tests/u-prio-queue.c',
   'unit-tests/u-reftable-tree.c',
+  'unit-tests/u-strbuf.c',
   'unit-tests/u-strvec.c',
 ]
 
@@ -57,7 +58,6 @@ unit_test_programs = [
   'unit-tests/t-reftable-readwrite.c',
   'unit-tests/t-reftable-record.c',
   'unit-tests/t-reftable-stack.c',
-  'unit-tests/t-strbuf.c',
   'unit-tests/t-strcmp-offset.c',
   'unit-tests/t-trailer.c',
   'unit-tests/t-urlmatch-normalization.c',

t/unit-tests/t-strbuf.c

@@ -0,0 +1,119 @@
+#include "unit-test.h"
+#include "strbuf.h"
+
+/* wrapper that supplies tests with an empty, initialized strbuf */
+static void setup(void (*f)(struct strbuf*, const void*),
+		  const void *data)
+{
+	struct strbuf buf = STRBUF_INIT;
+
+	f(&buf, data);
+	strbuf_release(&buf);
+	cl_assert_equal_i(buf.len, 0);
+	cl_assert_equal_i(buf.alloc, 0);
+}
+
+/* wrapper that supplies tests with a populated, initialized strbuf */
+static void setup_populated(void (*f)(struct strbuf*, const void*),
+			    const char *init_str, const void *data)
+{
+	struct strbuf buf = STRBUF_INIT;
+
+	strbuf_addstr(&buf, init_str);
+	cl_assert_equal_i(buf.len, strlen(init_str));
+	f(&buf, data);
+	strbuf_release(&buf);
+	cl_assert_equal_i(buf.len, 0);
+	cl_assert_equal_i(buf.alloc, 0);
+}
+
+static void assert_sane_strbuf(struct strbuf *buf)
+{
+	/* Initialized strbufs should always have a non-NULL buffer */
+	cl_assert(buf->buf != NULL);
+	/* Buffers should always be NUL-terminated */
+	cl_assert(buf->buf[buf->len] == '\0');
+	/*
+         * In case the buffer contains anything, `alloc` must alloc must
+         * be at least one byte larger than `len`.
+         */
+	if (buf->len)
+            cl_assert(buf->len < buf->alloc);
+}
+
+void test_strbuf__static_init(void)
+{
+	struct strbuf buf = STRBUF_INIT;
+
+	cl_assert_equal_i(buf.len, 0);
+	cl_assert_equal_i(buf.alloc, 0);
+	cl_assert(buf.buf[0] == '\0');
+}
+
+void test_strbuf__dynamic_init(void)
+{
+	struct strbuf buf;
+
+	strbuf_init(&buf, 1024);
+	assert_sane_strbuf(&buf);
+	cl_assert_equal_i(buf.len, 0);
+	cl_assert(buf.alloc >= 1024);
+	cl_assert(buf.buf[0] == '\0');
+	strbuf_release(&buf);
+}
+
+static void t_addch(struct strbuf *buf, const void *data)
+{
+	const char *p_ch = data;
+	const char ch = *p_ch;
+	size_t orig_alloc = buf->alloc;
+	size_t orig_len = buf->len;
+
+	assert_sane_strbuf(buf);
+	strbuf_addch(buf, ch);
+	assert_sane_strbuf(buf);
+	cl_assert_equal_i(buf->len, orig_len + 1);
+	cl_assert(buf->alloc >= orig_alloc);
+	cl_assert(buf->buf[buf->len] == '\0');
+}
+
+static void t_addstr(struct strbuf *buf, const void *data)
+{
+	const char *text = data;
+	size_t len = strlen(text);
+	size_t orig_alloc = buf->alloc;
+	size_t orig_len = buf->len;
+
+	assert_sane_strbuf(buf);
+	strbuf_addstr(buf, text);
+	assert_sane_strbuf(buf);
+	cl_assert_equal_i(buf->len, orig_len + len);
+	cl_assert(buf->alloc >= orig_alloc);
+	cl_assert(buf->buf[buf->len] == '\0');
+	cl_assert_equal_s(buf->buf + orig_len, text);
+}
+
+void test_strbuf__add_single_char(void)
+{
+	setup(t_addch, "a");
+}
+
+void test_strbuf__add_empty_char(void)
+{
+	setup(t_addch, "");
+}
+
+void test_strbuf__add_append_char(void)
+{
+	setup_populated(t_addch, "initial value", "a");
+}
+
+void test_strbuf__add_single_str(void)
+{
+	setup(t_addstr, "hello there");
+}
+
+void test_strbuf__add_append_str(void)
+{
+	setup_populated(t_addstr, "initial value", "hello there");
+}