bgcolor highlighting of ast nodes in traceback may be unreadable

[alexandru-dinu]

The commit 3026c20 introduced a change with a hard-coded bg:ansiyellow color.

Unfortunately, for some terminal color schemes, white-on-yellow may be unreadable, for example:

Changing to bg:ansired looks better:

Is it possible to make this option configurable?

Thank you!

[Carreau]

Duplicate #13446

[amerlyq]

Linked issue is locked, and as I understood it mostly focused on choosing new default color/style instead of exposing Token.ExecutingNode for style_overrides config option.

Mentioning that "bg:ansiyellow" is being only used as fallback in stack_data.style_with_executing_node(style, "bg:ansiyellow") is wrong. Because its value is used as override:

def style_with_executing_node(style, modifier):
    from pygments.styles import get_style_by_name
    if isinstance(style, str):
        style = get_style_by_name(style)

    class NewStyle(style):
        for_executing_node = True

        styles = {
            **style.styles,
            **{
                k.ExecutingNode: v + " " + modifier
                for k, v in style.styles.items()
            }
        }

Therefore we really don't have a way to modify it from user config -- only through modifiying sources itself.

[kanbara]

I have spent several hours reading the source and issues trying to override these colours. It's pretty bad for dark backgrounds, and I finally have the normal colours sorted, but I would really really really like the ability for the traceback to be customised-- especially the node colour. It's unusable on dark backgrounds and clashes with everything else.

[DanielO]

Being able to customise it would be ideal as currently is illegible on a dark terminal unless you have a muted yellow. Unfortunately I don't know how it's all plumbed together so I am not sure how to make the change.

For iTerm2 at least using anisred for the BG colour is quite legible for both light and dark (when editing the source).

If I change it like so:

        if self.has_colors:
            style = get_style_by_name("default")
            style = stack_data.style_with_executing_node(style, style.styles[pygments.token.Generic.Error])
            formatter = Terminal256Formatter(style=style)

(And add import pigments.token up the top) then it uses the existing error style rather than hard coding it - perhaps that is a suitable solution.

[0xquad]

Has there been plans to fix this issue?

First use after many years and experienced the problem immediately. Errors are unreadable, so the tool basically becomes impossible to use normally. I have to run things in a simple python console instead to see anything.

FYI I'm on Windows with Putty (Kitty fork). Tweaking the terminal colors is a huge hack at the very least and not a solution: only IPython outputs unreadable text (white on bright yellow) from all the things I've been using in the past years. (I'm actually surprised that it wasn't fixed before; it really should be a blocking issue in my book. Am I the only one having this issue? Otherwise is there any way I can disable this whole colored output in IPython (not the terminal) in order to restore usability?)

Also the original issue was locked ("off-topic" ?) so no one can comment there. Perhaps work is being done elsewhere?

Thanks for all the efforts put in IPython nonetheless, it's excellent!

[Carreau]

See #13756 as a workaround. But really most of the open issue that are not fixed is really because someone need to dive into them and do the work.