Update test_strings.py

Author: mmatera

test/builtin/test_strings.py

@@ -530,6 +530,8 @@ def test_private_doctests_patterns(str_expr, msgs, str_expected, fail_msg):
             "FromCharacterCode[{{97, 98, x}, {100, 101, x}}]",
             None,
         ),
+        
+        # These tests are commented out due to the bug reported in issue #906
         # Octal and hexadecimal notation works alone, but fails
         # as a part of another expression. For example,
         # F[\.78\.79\.7A]   or "\.78\.79\.7A" produces a syntax error in Mathics.
@@ -559,13 +561,14 @@ def test_private_doctests_characters(str_expr, msgs, str_expected, fail_msg):
         expected_messages=msgs,
     )
 
+# These tests are separated due to the bug reported in issue #906
 
 @pytest.mark.parametrize(
     ("str_expr", "str_expected", "fail_msg"),
     [
-        (r"\.78\.79\.7A", "xyz", "variable name using octal characters"),
-        (r"\:0078\:0079\:007A", "xyz", "variable name using octal characters"),
-        (r"\101\102\103\061\062\063", "ABC123", "variable name using octal characters"),
+        (r"\.78\.79\.7A", "xyz", "variable name using hexadecimal characters"),
+        (r"\:0078\:0079\:007A", "xyz", "variable name using hexadecimal characters"),
+        (r"\101\102\103\061\062\063", "ABC123", "variable name using hexadecimal characters"),
     ],
 )
 def test_private_doctests_characters(str_expr, str_expected, fail_msg):