Improved poutput() so that it can print an integer zero and other falsy things

The poutput() function has been ruggedized so that it has a better conditional check so that it will actually print
things which are "falsy" but are still convertible to a string.

A few unit tests have been added specifically for the poutput function.

1 files changed, 1 insertions, 1 deletions

diff --git a/cmd2.py b/cmd2.py
index dc34df6b..87fb3aad 100755
--- a/cmd2.py
+++ b/cmd2.py
@@ -585,7 +585,7 @@ class Cmd(cmd.Cmd):
         :param msg: str - message to print to current stdout - anyting convertible to a str with '{}'.format() is OK
         :param end: str - string appended after the end of the message if not already present, default a newline
         """
-        if msg:
+        if msg is not None and msg != '':
             try:
                 msg_str = '{}'.format(msg)
                 self.stdout.write(msg_str)