fix(tabs): Tab widget now supports custom padding (Fixes issue #502))

[rhaskia]

The tab widget now contains the values padding_left/padding_right and the function padding() that sets those values.
Should fix issue #502.

[codecov]

Codecov Report

Attention: 20 lines in your changes are missing coverage. Please review.

Comparison is base (1229b96) 90.7% compared to head (d4d3147) 90.6%.

Files	Patch %	Lines
src/widgets/tabs.rs	68.7%	20 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main    #629     +/-   ##
=======================================
- Coverage   90.7%   90.6%   -0.2%     
=======================================
  Files         42      42             
  Lines      12170   12232     +62     
=======================================
+ Hits       11042   11084     +42     
- Misses      1128    1148     +20     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[joshka]

Cool. I didn't realize that the spacing before the tabs was coming from padding left / right. My mental model without having looked at the code was that the spaces "belonged to the divider. This solution is better than the ones on the Issue.

A question though, what if we made the padding accept &str instead of just a number?

A follow up to this might be to make padding accept Line to make the divider / padding able to be styled easily.
Imagine:

🭊🭁Tab 1🭌🬿 🭊🭁Tab 2🭌🬿

But with the background of the label part the same color as the tab padding parts.

(copied from the discord feedback so that it's recorded for posterity)

[joshka]

approved by mistake

[joshka]

We can include the padding part of the tabs in the highlight by adding it to the tab titles instead of the padding. So I wonder whether it would be the worst thing to omit the highlight part of this?

Can you please add some docs about padding to the main rustdoc comment for the type? The doc needs info on the defaults for the padding and divider.

I'm going to make a breaking change for highlight_style in another PR as it seems natural to make that actually do something reasonable in the default configuration.

[joshka]

Hey, would you mind setting up commit signing?
https://github.com/ratatui-org/ratatui/blob/main/CONTRIBUTING.md#sign-your-commits

[rhaskia]

I did, I think something went wrong as it says the email does not match the signature.

[joshka]

Github mangles your email address to 94507929+RhaskiaGameDev@users.noreply.github.com is that setup as being valid for signing?

[joshka]

Thanks for fixing up the commit signing - Github still complains that it can't merge them as it needs all the commits to be signed. Can you please squash the commits into a single signed commit and force push the single commit as an update to your branch?

[joshka]

Just merged this - thanks again for the PR :)