simple pretty print for tables

ascii-table.py

# This code is available under the MIT license: https://opensource.org/licenses/MIT
#
# 2022-07-29 Added from_dict helper, textwrapping, max_width, and typehinted to Sequence instead of list.

from itertools import zip_longest
import textwrap
from typing import Callable, List, Optional, Sequence


def text_width(text: str) -> int:
    return len(max(text.split("\n"), key=len))


def max_text_width(texts: List[str]) -> int:
    return len(max(texts, key=text_width))


def format_table(
    table: Sequence[Sequence[str]],
    headers: Optional[Sequence[str]] = None,
    justify: Callable[[str, int], str] = str.ljust,
    max_width: int = 20,
) -> str:
    if headers is None:
        headers = [""] * len(table)
    col_lens = [
        min(max_width, max_text_width([headers[i]] + list(col)))
        for i, col in enumerate(table)
    ]
    output = ""
    if max(headers, key=len) != "":
        output += (
            " | ".join(justify(item, col_lens[i]) for i, item in enumerate(headers))
            + "\n"
        )
        output += " | ".join("-" * col_lens[i] for i, _ in enumerate(table)) + "\n"

    for row in zip(*table):
        justified = [justify(item, col_lens[i]) for i, item in enumerate(row)]
        wrapped = [textwrap.wrap(i, width=max_width) for i in justified]
        for line_elems in zip_longest(*wrapped, fillvalue=""):
            output += (
                " | ".join(
                    justify(item, col_lens[i]) for i, item in enumerate(line_elems)
                )
                + "\n"
            )

    return output


def format_table_from_dict(
    table: dict[str, List[str]],
    justify: Callable[[str, int], str] = str.ljust,
    max_width: int = 20,
):
    return format_table(
        list(table.values()),
        headers=list(table.keys()),
        justify=justify,
        max_width=max_width,
    )


print(format_table([["aaa, aaaaaa"], ["bb", "b"]], headers=["a", "a bunch of b's"]))
# a           | a bunch of b's
# ----------- | --------------
# aaa, aaaaaa | bb