click.confirm does not cooperate with readline

[alex-ball]

This follows on from #665.

Consider this code again, using click.confirm instead of click.prompt:

import click, readline
click.confirm("Input")

• Type anything then backspace
  • Actual behaviour: the entire line is erased
  • Expected behaviour: only the entered character is erased
• Type return only
  • Actual behaviour: no newline is printed to the terminal (a following click.echo() or print() will appear to be ignored)
  • Expected behaviour: a newline is printed to the terminal

The solution from PR #1836 seems to work in the case of click.confirm as well:

    while True:
        try:
            # Write the prompt separately so that we get nice
            # coloring through colorama on Windows
            echo(prompt.rstrip(" "), nl=False, err=err)
            value = visible_prompt_func(" ").lower().strip()

Environment:

• Python version: 3.8.10
• Click version: 8.0.1

[davidism]

Happy to review a PR