refactor: string extend method

test/string/str2.c

@@ -1,27 +1,34 @@
-#include <assert.h>
-#include <string.h>
-
-#include "../../string/mystring.h"
-
-void test_str2(void) {
-	mcl_string_s *s1 = mcl_string_new("Hello, world!", 0);
-	assert(s1 != NULL);
-	mcl_string_s *s2 = mcl_string_new("Hello, world!", 0);
-	assert(s2 != NULL);
-	/* Don't call mcl_string_cstr() more than once in the same printf function */
-
-	int ret = mcl_string_compare(s1, s2);
-	assert(ret == 0);
-
-	mcl_string_clear(s1);
-	ret = mcl_string_compare(s1, s2);
-	assert(ret != 0);
-
-	mcl_string_tolower(s1);
-	mcl_string_toupper(s2);
-	assert(strcmp(mcl_string_cstr(s1), "") == 0);
-	assert(strcmp(mcl_string_cstr(s2), "HELLO, WORLD!") == 0);
-
-	mcl_string_free(s1);
-	mcl_string_free(s2);
-}
+#include <assert.h>
+#include <string.h>
+
+#include "../../string/mystring.h"
+
+void test_str2(void) {
+	mcl_string_s *s1 = mcl_string_new("Hello, world!", 0);
+	assert(s1 != NULL);
+	mcl_string_s *s2 = mcl_string_new("Hello, world!", 0);
+	assert(s2 != NULL);
+	/* Don't call mcl_string_cstr() more than once in the same printf function */
+
+	int ret = mcl_string_compare(s1, s2);
+	assert(ret == 0);
+
+	mcl_string_clear(s1);
+	ret = mcl_string_compare(s1, s2);
+	assert(ret != 0);
+
+	mcl_string_tolower(s1);
+	mcl_string_toupper(s2);
+	assert(strcmp(mcl_string_cstr(s1), "") == 0);
+	assert(strcmp(mcl_string_cstr(s2), "HELLO, WORLD!") == 0);
+
+	/* Extend a string */
+	mcl_string_s *extend_me = mcl_string_new("This string is suuuuuuuuuuuuuuuuuuuuuper extended!", 0);
+	mcl_string_extend(s1, extend_me);
+	assert(mcl_string_length(s1) == 50);
+	assert(mcl_string_capacity(s1) == 64);
+
+	mcl_string_free(s1);
+	mcl_string_free(s2);
+	mcl_string_free(extend_me);
+}