Use ... to indicate default columns for Progress

[ptmcg]

rich.progress.Progress uses these columns as default if no columns are specified:

    TextColumn("[progress.description]{task.description}"),
    BarColumn(),
    TextColumn("[progress.percentage]{task.percentage:>3.0f}%"),
    TimeRemainingColumn(),

If I just want to specify some extensions, I have to give the whole list of columns, including the defaults. For instance, to add a Spinner before and a TimeElapsed after, I have to do this:

# current Progress construction
# add spinner before and elapsed after default columns
with Progress(
    SpinnerColumn(),
    TextColumn("[progress.description]{task.description}"),
    BarColumn(),
    TextColumn("[progress.percentage]{task.percentage:>3.0f}%"),
    TimeRemainingColumn(),
    TimeElapsedColumn(),
    console=console,
    transient=True,
) as progress:

Wouldn't it be a friendlier API to accept ... as a value indicating "default columns here", so that this same code could be written as:

# Progress construction using ... as placeholder for the default columns
# add spinner before and elapsed after default columns
with Progress(
    SpinnerColumn(),
    ...,
    TimeElapsedColumn(),
    console=console,
    transient=True,
) as progress:

Or as a more conventional option, define the default columns as a classmethod:

# Progress construction using ... as placeholder for the default columns
# add spinner before and elapsed after default columns
with Progress(
    SpinnerColumn(),
    *Progress.default_columns(),
    TimeElapsedColumn(),
    console=console,
    transient=True,
) as progress:

Just so I don't have to hard-code the default columns in my own code.

[willmcgugan]

Hi Paul,

Yeah, I think this is a good idea.

[willmcgugan]

#1891

[ptmcg]

After writing that post, I think I'll just do a PR that adds the classmethod. "..." as a parameter might be sexy, but it defies typing, so I take that as a sign.

[willmcgugan]

Fair enough. Would it not accept the arguments as a Union of Column and EllipsisType ?

[ptmcg]

I tried, but Ellipsis is not a valid type for typing, it turns out, nor is type(Ellipsis).

[willmcgugan]

Interesting, looks like there is an EllipsisType in 3.10 https://docs.python.org/3/library/types.html#types.EllipsisType

Shame, it was sexy. Guess classmethod will have to do.

[ptmcg]

Darn that "compatibility with older Python versions" thing!

[ptmcg]

Hrmmmm, PR failed to build. "Works on my machine."

[willmcgugan]

Weird error on the Windows CI. Doesn't look related to your change. Will re-run jobs in case it was a glitch.

[ptmcg]

PR merged - next release will have get_default_columns() classmethod on Progress.