How to test?

[Manfred Lotz]

On Sat, 25 Apr 2020 08:25:00 +1200
DL Neil <PythonList at DancesWithMice.info> wrote:

> On 25/04/20 6:40 AM, Manfred Lotz wrote:
> > I have a command like application which checks a directory tree for
> > certain things. If there are errors then messages will be written to
> > stdout.
> > 
> > How to test this in the best way?
> > 
> > One idea was for the error situations to write messages to files and
> > then later when running the tests to compare the error messages
> > output to the previously saved output.
> > 
> > Is there anything better?  
> 
> Yes, as well as reproducing the output on-screen, there are now three 
> ways to deal with stdout. The newest is "tee", which like the Linux 
> command of the same name, gives the best of both worlds - display and 
> 'capture'!
> 
> Capturing of the stdout/stderr output
> https://docs.pytest.org/en/latest/capture.html
> 
> 

This is interesing.

> May I point-out that the above may not be the best approach. Rather
> than using screen-prints to report errors, another method is to
> utilise "logging" to collect such data - so that there is always a
> formal record (regardless of user behavior). During 'production' the
> information could be collected at some central 'location' for
> inspection by competent staff. During 'development', it is possible,
> by changing one line, to re-direct the log to wherever you would like
> - including the above!
> 

Logging wouldn't help here as the person running the program is
competent, and it likes to see what the errors are.

-- 
Manfred