@csabella perhaps you'd like to review this?

@taleinat Thanks for asking me to take a look at this PR.

This is certainly an interesting change to consider, especially with issue33397 and Terry's idea to use that font resizing class for all windows. Since the TextView is currently used for help_about and the help button on config dialog, I'm lumping it in with the other Help screens (and the current change addressed in issue33397), but I also think Terry wanted to expand the use of TextView into other areas, which makes me think consistency across the app for fg and bg would also be a goal.

When we notice something like this that should be changed, Terry usually opens a master bug tracker issue to make sure any related changes are also done. For example, this doesn't address the help.py window because it's not a TextView, but perhaps the overarching project would be to make all the colors and all the fonts consistent across the app.

Also, I noticed that this color_config method was just added two years ago. I'm not familiar with all the intended changes for the colorizer, but it seems like this function doesn't really fit in with the other comment in the docstring for that method - 'Should be called whenever ColorDelegator is called. ' In the case of adding this to TextView, you aren't calling ColorDelegator. Not that this affects your change because I think you are using the method in the way it was intended, but the color_config method just doesn't seem to be defined quite exactly in the way it should be used. Either it needs to change (in the docstring) for your usage or else you shouldn't be using it. I hope that makes sense.

My thought without having Terry's input is the color_config should live somewhere else. It's setting up a text widget, not really being used as part of the delegator, but maybe that's a wrong assumption because I haven't spent a lot of time with it.

A lot of the recent work on IDLE has been small changes (sometimes behind the scenes) to get the modules ready for a user-facing change. Based on that, even though your change is a good idea, I'm not sure if it should be step one or if colorizer needs some work first. Or if a new text_config module will be added that will handle both fg/bg color and resizing for text.

As far as the project as it is now, I do think you should add tests for the colors. If this gets added to other modules for consistency, then the tests would be able to show that consistency, that is, before the change is made, the assert would fail and then after use color_config to set the color, the assert would pass.

In bpo-27117, I extracted the color_config code from Editor_Window.__init__ so that configured colors could be used with any text widget. The use then was for turtledemo (which uses colorizer) and the colorizer htest. I will modify the docstring. (I think the function is OK where it is ;-).

Thanks @taleinat for the PR 🌮🎉.. I'm working now to backport this PR to: 3.6, 3.7.
🐍🍒⛏🤖

GH-9513 is a backport of this pull request to the 3.7 branch.

GH-9514 is a backport of this pull request to the 3.6 branch.

I'm not backporting this to 2.7 since @terryjreedy's refactoring out of color_config() wasn't backported to it, and this PR depends on that.