Indent text in Rich, optionally with different indent on the first line.

indent.py

"""Indent Rich text or renderable."""

from dataclasses import dataclass
from typing import Optional

from rich.abc import RichRenderable
from rich.console import Console, ConsoleOptions, RenderResult
from rich.segment import Segment


@dataclass
class Indent:
    """Indent a Rich renderable, with a different indent for the first line."""

    renderable: RichRenderable
    level: int
    first_line_level: Optional[int] = None

    def __rich_console__(
        self, console: Console, options: ConsoleOptions
    ) -> RenderResult:
        segments = console.render(self.renderable, options)
        lines = Segment.split_lines(segments)
        printing_first_line = True
        indent = (
            self.first_line_level if self.first_line_level is not None else self.level
        )
        for line in lines:
            yield Segment(" " * indent)
            yield from line
            yield Segment("\n")
            if printing_first_line:
                printing_first_line = False
                indent = self.level


if __name__ == "__main__":
    from rich.table import Table
    from rich.text import Text

    con = Console()
    lorem = Text(
        "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod "
        "tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, "
        "quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo "
        "consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse "
        "cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non "
        "proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
    )
    hanging = Indent(lorem, level=10, first_line_level=0)
    con.rule("Normal printing")
    con.print(hanging)
    con.line(2)
    table = Table("Normal", "Hanging")
    table.add_row(lorem, hanging)
    con.print(table)