Disabling custom font sizes does not remove 'custom' option from Paragraph block font size dropdown

[badlydrawnben]

The dropdown of theme-defined font sizes also has a 'Custom' option, even though I have defined the theme font sizes and removed support for custom font sizes.

To reproduce:
Blank installation of WP 5.2.3 and TwentyNineteen theme.
Install and enable Gutenberg plugin (v6.6.0)
Add this snippet to functions.php
add_theme_support('disable-custom-font-sizes');

Expected behaviour:
The custom text size input field should not be shown - works as expected
The dropdown of text sizes (eg small, medium, large etc) should not also include 'Custom' as an option because that functionality has been removed by that snippet - Does not work as expected.

Note - this problem does not exist if the Gutenberg plugin is deactivated.

[Waqas-Ali-Azhar]

Hi @badlydrawnben , i reproduced the issue and tried adding a pull request here to resolve the issue.
#18049

[gziolo]

Copying over from #18212 which turned out to be a duplicate:

Describe the bug
Originally reported in #18149:

The example which has the custom sizes disabled works only partially, since, in the dropdown, there is still
an option labeled Custom:

To reproduce
Steps to reproduce the behavior:

1. Run Storybook: npm run design-system:dev or open https://wordpress.github.io/gutenberg/design-system/components/.
2. Go to the FontSizePicker section.
3. Pick the one named Without Custom Sizes
4. Check the select box.

Expected behavior
There is no Custom option when disableCustomFontSizes flag is passed to FontSizePicker component.

Desktop (please complete the following information):

• OS: macOS
• Browser Chrome
• Version 77

[mtias]

@gziolo is this still the case?

[gziolo]

We should have a different custom font size picker now, so it might be no longer a case. @sarayourfriend or @ciampo can you confirm?

At least in Storybook, it works as expected:

[ciampo]

We should have a different custom font size picker now, so it might be no longer a case. @sarayourfriend or @ciampo can you confirm?

I'm personally not familiar with this component, but looking at the folder history, there's been quite a few changes to its source code (refactors and bug fixes)

At least in Storybook, it works as expected

I can confirm that the "Without Custom Sizes" storybook story seems to work as expected (and therefore doesn't reproduce the original bug in this issue)

[smileBeda]

This is frustrating.

It is by far the worst result off what bad naming conventions can do.

add_theme_support( 'disable-custom-colors' );
...?!

==> remove_theme_support( 'custom-line-height' ); everyone gets it!
==> add_theme_support( 'disable-custom-colors' ); ... 🫨 couldn't it just be named according to other such supports, namely, that would be remove_theme_support( 'custom-colors' );. Duh. Simple, and doc would also still make sense, which now it clearly doesn't anymore (see https://developer.wordpress.org/reference/functions/remove_theme_support/, which basically encourages to use remove_theme_support on those self-negating features.

So, in other words, you have to do linguistical and logical mind juggling to understand what what does.

Can't something be done about this?

🤷

[ciampo]

Hey @smileBeda ,

I'm not sure that the point you're raising is relevant to this specific issue. I would encourage you to open a separate issue or discussion, while also adopting a spirit of collaboration and assuming positive intent from the open source community.