scalar-diagnose: add directory to archiver more gently

If a directory added to the 'scalar diagnose' archiver does not exist, warn
and return 0 from 'add_directory_to_archiver()' rather than failing with a
fatal error. This handles a failure edge case where the '.git/logs' has not
yet been created when running 'scalar diagnose', but extends to any
situation where a directory may be missing in the '.git' dir.

Now, when a directory is missing a warning is captured in the diagnostic
logs. This provides a user with more complete information than if 'scalar
diagnose' simply failed with an error.

Helped-by: Junio C Hamano <[email protected]>
Signed-off-by: Victoria Dye <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: vdye

contrib/scalar/scalar.c

@@ -266,14 +266,20 @@ static int add_directory_to_archiver(struct strvec *archiver_args,
 					  const char *path, int recurse)
 {
 	int at_root = !*path;
-	DIR *dir = opendir(at_root ? "." : path);
+	DIR *dir;
 	struct dirent *e;
 	struct strbuf buf = STRBUF_INIT;
 	size_t len;
 	int res = 0;
 
-	if (!dir)
+	dir = opendir(at_root ? "." : path);
+	if (!dir) {
+		if (errno == ENOENT) {
+			warning(_("could not archive missing directory '%s'"), path);
+			return 0;
+		}
 		return error_errno(_("could not open directory '%s'"), path);
+	}
 
 	if (!at_root)
 		strbuf_addf(&buf, "%s/", path);