[BUG] `Columns(width=...)` raises `ZeroDivisionError` when the requested width does not fit

[yayong3]

• I've checked docs and closed issues for possible solutions.
• I can't find my issue in the FAQ.

Describe the bug

With the default padding (0, 1), width_padding is 1. If the available console width is no greater than width + 1, this calculation returns 0. This will result in an error.
This bug might be related to the following code in rich\columns.py within rich.

def __rich_console__:
       ...
        if self.width is not None:
            column_count = (max_width) // (self.width + width_padding)

__rich_console__ then passes column_count to iter_renderables, which evaluates item_count % column_count and raises ZeroDivisionError.

Reproduction

from io import StringIO

from rich.columns import Columns
from rich.console import Console

console = Console(
    file=StringIO(),
    width=16,
    height=24,
    force_terminal=True,
    color_system=None,
    highlight=False,
)
print("size", console.width, "x", console.height)
console.print(Columns([f"file_{i:02d}.txt" for i in range(8)], width=16))

Observed:

size 16 x 24
Traceback (most recent call last):
  File "/home/test01.py", line 15, in <module>
    console.print(Columns([f"file_{i:02d}.txt" for i in range(8)], width=16))
  File "/home/rich/rich/console.py", line 1731, in print
    extend(render(renderable, render_options))
  File "/home/rich/rich/console.py", line 1339, in render
    for render_output in iter_render:
  File "/home/rich/rich/columns.py", line 145, in __rich_console__
    _renderables = [
                   ^
  File "/home/rich/rich/columns.py", line 115, in iter_renderables
    if item_count % column_count:
       ~~~~~~~~~~~^~~~~~~~~~~~~~
ZeroDivisionError: integer modulo by zero

Same function, zero divisor (optional second case):

console.print(Columns(["alpha", "beta"], width=0, padding=0))

  File "/home/rich/rich/columns.py", line 124, in __rich_console__
    column_count = (max_width) // (self.width + width_padding)
                   ~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ZeroDivisionError: integer division or modulo by zero

Platform

• Python version: 3.12.3
• Rich version: 15.0.0 (9d8f9a37)
• Linux x86_64

[eminsk]

I took a look at this and reproduced the crash with a test case.

When max_width <= self.width + width_padding (or with width=0, padding=0), column_count in rich/columns.py evaluates to 0, causing the ZeroDivisionError when iterating.

Guarding column_count with max(1, ...) resolves the issue cleanly:

column_count = (
    max(1, max_width // (self.width + width_padding))
    if (self.width + width_padding) > 0
    else 1
)

I've put together a fix with regression tests on my fork:

• Commit: eminsk/rich@c9f68f3
• Branch: fix/columns-zero-division

Since PRs are currently limited to collaborators on this repo, feel free to cherry-pick this directly or let me know if you'd like me to open a PR once permissions allow.