Refactor version printing in CLI with Click

[alichtman]

Here's a good example

def print_version(ctx, param, value):
    if not value or ctx.resilient_parsing:
        return
    click.echo('Version 1.0')
    ctx.exit()

@click.command()
@click.option('--version', is_flag=True, callback=print_version,
              expose_value=False, is_eager=True)
def hello():
    click.echo('Hello World!')

[nunomdc]

Here do we want to just duplicate the functionality of the current print_version_info function on a new one specific to Click?
Because it seems that there is a requirement regarding the print_version function arguments.

Or instead make the existing function only return the version string and move it to e.g. utils.py

[alichtman]

I'm actually not sure this makes sense to change. The way it's engineered at the moment works fine for both the -v arg and the CLI splash screen. Let's just leave this as it is.

[nunomdc]

Can we at least make it so both "-v" and "--version" work to print the version information?

[alichtman]

Yep, this should be as easy as adding --version to the click option.

Open an Issue (#162)

Open a PR and I'll merge it.

@nunomdc