Only first line of ValidationError message is displayed.

[ryneeverett]

When the error message has multiple lines, only the first is displayed.

from prompt_toolkit.validation import Validator, ValidationError
from prompt_toolkit import prompt

class NumberValidator(Validator):
    def validate(self, document):
        text = document.text

        if text and not text.isdigit():
            i = 0

            # Get index of fist non numeric character.
            # We want to move the cursor here.
            for i, c in enumerate(text):
                if not c.isdigit():
                    break

            raise ValidationError(message='This input contains non-numeric characters.\nTHIS IS NOT DISPLAYED.',
                                  cursor_position=i)


number = int(prompt('Give a number: ', validator=NumberValidator()))
print('You said: %i' % number)

[jonathanslenders]

That's a bug. Thanks for pointing out! It should not be too hard to fix.

[jonathanslenders]

Looking again at the code, it's not as trivial as I was thinking.

The layout engine does not support a Window to prefer as much height as the ContainerControl would require. (This is extremely difficult to do, due to the order of how widths and heigths are calculated and due to how we need to calculate the widths of all the lines, taking double width characters and line wrapping into account, to calculate the total required height.)

However, I think we could turn the validation error into a "float" control, just like how we show the help message in the menu of ptpython. I'll think about that.