util: rework strappenda(), and rename it strjoina()

After all it is now much more like strjoin() than strappend(). At the
same time, add support for NULL sentinels, even if they are normally not
necessary.

1 files changed, 24 insertions, 12 deletions

diff --git a/src/test/test-util.c b/src/test/test-util.c
index f2b7038a4..804f522e9 100644
--- a/src/test/test-util.c
+++ b/src/test/test-util.c
@@ -1072,17 +1072,29 @@ static void test_strshorten(void) {
         assert_se(strlen(strshorten(s, 0)) == 0);
 }
 
-static void test_strappenda(void) {
+static void test_strjoina(void) {
         char *actual;
 
-        actual = strappenda("", "foo", "bar");
+        actual = strjoina("", "foo", "bar");
         assert_se(streq(actual, "foobar"));
 
-        actual = strappenda("foo", "bar", "baz");
+        actual = strjoina("foo", "bar", "baz");
         assert_se(streq(actual, "foobarbaz"));
 
-        actual = strappenda("foo", "", "bar", "baz");
+        actual = strjoina("foo", "", "bar", "baz");
         assert_se(streq(actual, "foobarbaz"));
+
+        actual = strjoina("foo");
+        assert_se(streq(actual, "foo"));
+
+        actual = strjoina(NULL);
+        assert_se(streq(actual, ""));
+
+        actual = strjoina(NULL, "foo");
+        assert_se(streq(actual, ""));
+
+        actual = strjoina("foo", NULL, "bar");
+        assert_se(streq(actual, "foo"));
 }
 
 static void test_is_symlink(void) {
@@ -1231,13 +1243,13 @@ static void test_execute_directory(void) {
         assert_se(mkdtemp(template_lo));
         assert_se(mkdtemp(template_hi));
 
-        name = strappenda(template_lo, "/script");
-        name2 = strappenda(template_hi, "/script2");
-        name3 = strappenda(template_lo, "/useless");
-        overridden = strappenda(template_lo, "/overridden");
-        override = strappenda(template_hi, "/overridden");
-        masked = strappenda(template_lo, "/masked");
-        mask = strappenda(template_hi, "/masked");
+        name = strjoina(template_lo, "/script");
+        name2 = strjoina(template_hi, "/script2");
+        name3 = strjoina(template_lo, "/useless");
+        overridden = strjoina(template_lo, "/overridden");
+        override = strjoina(template_hi, "/overridden");
+        masked = strjoina(template_lo, "/masked");
+        mask = strjoina(template_hi, "/masked");
 
         assert_se(write_string_file(name, "#!/bin/sh\necho 'Executing '$0\ntouch $(dirname $0)/it_works") == 0);
         assert_se(write_string_file(name2, "#!/bin/sh\necho 'Executing '$0\ntouch $(dirname $0)/it_works2") == 0);
@@ -1562,7 +1574,7 @@ int main(int argc, char *argv[]) {
         test_read_one_char();
         test_ignore_signals();
         test_strshorten();
-        test_strappenda();
+        test_strjoina();
         test_is_symlink();
         test_pid_is_unwaited();
         test_pid_is_alive();