# HG changeset patch
# User Rik <rik@octave.org>
# Date 1585260369 25200
# Node ID 47d4a84a57253b7bd47d6cecabd7a2b56a7caa35
# Parent  e3ef089c5529818a7f0a1d53856f56adc5eac629
fieldnames.m: Fix handling of old-style @class objects (bug #58012).

* fieldnames.m: Add try/catch block to first use classdef access sequence and
then fall back to @class access sequence.  Add BIST test for @class objects.

diff -r e3ef089c5529 -r 47d4a84a5725 scripts/miscellaneous/fieldnames.m
--- a/scripts/miscellaneous/fieldnames.m	Wed Mar 25 18:29:20 2020 +0100
+++ b/scripts/miscellaneous/fieldnames.m	Thu Mar 26 15:06:09 2020 -0700
@@ -52,7 +52,11 @@
   if (isstruct (obj))
     names = __fieldnames__ (obj);
   elseif (isobject (obj))
-    names = properties (obj);
+    try
+      names = properties (obj);      ## classdef object
+    catch
+      names = __fieldnames__ (obj);  ## @class object
+    end_try_catch
   elseif (isjava (obj) || ischar (obj))
     ## FIXME: Function prototype that accepts java obj exists, but doesn't
     ##        work if obj is java.lang.String.  Convert obj to classname.
@@ -87,6 +91,12 @@
 %! f = fieldnames (m);
 %! assert (f, {"Count"; "KeyType"; "ValueType"; "map"; "numeric_keys"});
 
+## Test old-style @class object
+%!test
+%! obj = ftp ();
+%! f = fieldnames (obj);
+%! assert (f, {"host"; "username"; "password"; "curlhandle"});
+
 ## Test Java classname by passing classname
 %!testif HAVE_JAVA; usejava ("jvm")
 %! names = fieldnames ("java.lang.Double");