t/run/todo.t: Add comments

Add a list of issues that we don't need TODO tests for, so that someone
doesn't waste their efforts.

Author: khwilliamson

t/run/todo.t

@@ -1,9 +1,16 @@
 #!./perl
 
-# This file is a place for tests that fail at the time they are added here.
+# This file is a place for tests that are failing at the time they are added
+# into this file.  It exists so that anyone can contribute a test without
+# having to know about Perl's testing structures.
 #
-# When a ticket is filed, just follow the paradigm(s) in this file to add a
-# test that shows the failure.
+# When a new ticket is filed, just follow the paradigm(s) in this file to add
+# a test that shows the failure.  However, some domains have infrastructure
+# which may make it easier to add a test there, than to have to set up things
+# here.  These include:
+#     Domain              Test File
+#   deparsing           lib/B/Deparse.t
+#   regex matching      t/re/re_tests
 #
 # It is expected that when new tickets are opened, some will actually be
 # duplicates of existing known bad behavior.  And since there are so many open
@@ -13,6 +20,29 @@
 # disposition of the test here determined at that time.  (For example, perhaps
 # it is redundant to the test demonstrating the bug that was intentionally
 # fixed, so can be removed altogether.)
+#
+# Before you add a test here, check that the ticket isn't one of these,
+# because we already have todo tests for them (in some other file).
+#
+# Git Hub issue numbers
+#    2207
+#    2208
+#    2286
+#    2931
+#    4125
+#    4261
+#    4370
+#    5959
+#    8267
+#    8945
+#    8952
+#    9010
+#    9406
+#    10750
+#    14052
+#    19370
+#    19661
+#    22547
 
 BEGIN {
     chdir 't' if -d 't';