Add test for stpcpy().

test/val/stpcpy.c

@@ -0,0 +1,44 @@
+// 2024-07-15 Sven Michael Klose <pixel@hugbox.org>
+
+#include <assert.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#define STR_SHORT   "Hello, World!"
+#define STR_LONG    "This is a longer test string for stpcpy."
+
+int
+main ()
+{
+    char dest[50];
+    const char *src_empty;
+    const char *src_short;
+    const char *src_long;
+    char       *end;
+
+    src_empty = "";
+    end = stpcpy (dest, src_empty);
+    assert(!strcmp (dest, src_empty));
+    assert(!*end);
+    assert(end == dest);
+    printf ("Test 1 passed.\n");
+
+    src_short = STR_SHORT;
+    end = stpcpy (dest, src_short);
+    assert(!strcmp (dest, src_short));
+    assert(!*end);
+    assert(end == &dest[sizeof (STR_SHORT) - 1]);
+    printf ("Test 2 passed.\n");
+
+    src_long = STR_LONG;
+    end = stpcpy (dest, src_long);
+    assert(!strcmp (dest, src_long));
+    assert(!*end);
+    assert(end == &dest[sizeof (STR_LONG) - 1]);
+    printf ("Test 3 passed.\n");
+
+    printf ("All tests passed.\n");
+    return EXIT_SUCCESS;
+}
+