Click: prompt option fails with multiple=True

[noqqe]

Hi,

Imagine you have cli software (like me) with the following option:

@click.option('categories', '-c', '--categories',
              type=str,
              multiple=True,
              prompt="Categories",
              default="foo",
              help='Set categories for this document')

So if you dont provide this parameter, you get prompted for it.

Categories [(u'f', u'o', u'o')]:

Please help me understand in what way splitting up the parameters this way makes sense. Im really having a hard time thinking about it.

Wouldn't it make much more sense to split them by space?

In the meantime, i worked around using the following, within my function:

categories = ''.join(list(categories)).split()

I've also found Issue 218, but the answer is not really satisfying.

[untitaker]

Please help me understand in what way splitting up the parameters this way makes sense.

Since multiple=True and type=str mean that you can provide _multiple string_ values, the default value is interpreted as an iterable of strings. If you iterate over a string, you get its individual characters.

However, I agree with you that splitting by characters isn't really desirable when _entering_ a value into the prompt.

I'd really like to see this behavior explicitly disallowed or properly implemented.

cc @mitsuhiko, ref #218

[jcrotts]

It seems like this should just be disallowed based on comments from @untitaker and @mitsuhiko.