feat: added tests

tests/char.c

@@ -0,0 +1,62 @@
+#include "test.h"
+#include "libft.h"
+
+TEST(test_isalpha) {
+    ASSERT(ft_isalpha('a'));
+    ASSERT(ft_isalpha('Z'));
+    ASSERT(!ft_isalpha('1'));
+    ASSERT(!ft_isalpha('@'));
+    ASSERT(!ft_isalpha(' '));
+}
+
+TEST(test_isdigit) {
+    ASSERT(ft_isdigit('0'));
+    ASSERT(ft_isdigit('9'));
+    ASSERT(!ft_isdigit('a'));
+    ASSERT(!ft_isdigit(' '));
+    ASSERT(!ft_isdigit('#'));
+}
+
+TEST(test_islower) {
+    ASSERT(ft_islower('a'));
+    ASSERT(ft_islower('z'));
+    ASSERT(!ft_islower('A'));
+    ASSERT(!ft_islower('0'));
+    ASSERT(!ft_islower(' '));
+}
+
+TEST(test_isupper) {
+    ASSERT(ft_isupper('A'));
+    ASSERT(ft_isupper('Z'));
+    ASSERT(!ft_isupper('a'));
+    ASSERT(!ft_isupper('0'));
+    ASSERT(!ft_isupper(' '));
+}
+
+TEST(test_tolower) {
+    ASSERT(ft_tolower('A') == 'a');
+    ASSERT(ft_tolower('Z') == 'z');
+    ASSERT(ft_tolower('a') == 'a');
+    ASSERT(ft_tolower('z') == 'z');
+    ASSERT(ft_tolower('1') == '1');
+    ASSERT(ft_tolower(' ') == ' ');
+}
+
+TEST(test_toupper) {
+    ASSERT(ft_toupper('a') == 'A');
+    ASSERT(ft_toupper('z') == 'Z');
+    ASSERT(ft_toupper('A') == 'A');
+    ASSERT(ft_toupper('Z') == 'Z');
+    ASSERT(ft_toupper('1') == '1');
+    ASSERT(ft_toupper(' ') == ' ');
+}
+
+int main(void) {
+    RUN_TEST(test_isalpha);
+    RUN_TEST(test_isdigit);
+    RUN_TEST(test_islower);
+    RUN_TEST(test_isupper);
+    RUN_TEST(test_tolower);
+    RUN_TEST(test_toupper);
+    return 0;
+}