Creating one dark style

[TobiZog]

I creating a new style, orientated by the "One Dark Theme" for Atom. I hope you will add it to the package.

[Anteru]

Thanks for the contribution! Looks like it's missing the license/copyright, hence failing the checks. Can you fix that, please?

[TobiZog]

I corrected this. I hope it will pass now.

[TobiZog]

Can you please approve this?

[Anteru]

Merged, thanks!

[ranelpadon]

@TobiZog @Anteru Thanks a lot for this One Dark theme, which is my favorite. This is timely PR also since I'm tinkering with IPython/Pygments recently, and will write an article for it. Hopefully, this will be released to PyPI asap since the last release was still 2.10.0 (August 15), and so that I could just say pip install pygments to the readers. Otherwise, need to instruct them to do some manual changes to the styles folder also. :)

[ranelpadon]

@TobiZog I'm using One Dark theme in my Alacritty terminal and Vim/Neovim/MacVim editors. I just noticed that some colors in Pygments' One Dark theme are bit off when running IPython. When I dig further, there are indeed subtle differences in some of the colors used. In the screenshot below, the top colors are the Pygments' One Dark, the bottom colors are the "expected" colors. I rearranged the tokens for easier comparison. It looks like that the Pygments' One Dark version are bit strong:

Maybe we could follow the Vim's One Dark or Alacritty's One Dark as the "expected" values since they are quite popular and their color values are consistent with each other. Likewise, I checked with Atom's original HSL values, they are correct/consistent. Other colors in Pygments' One Dark are correct/consistent though.

Actually, I submitted also before the One Dark theme for Thonny IDE and used the same values.

Is it okay to submit a PR to refine them? Otherwise, I'll submit another variant of Pygments' One Dark theme. Ideally, there should be only 1 version, and we should align with other projects for consistency and minimize confusion to Pygments users. Thanks :)

CC: @Anteru

[Anteru]

@ranelpadon I'm ok with a PR but I'm afraid it's going to reduce the contrast. I guess we'll see once you submit it. We're trying to be a bit more conscious about accessibility and not have tons of new styles with bad contrast.

[ranelpadon]

@Anteru I don't think the contrast is an issue here since it's being used in other popular open-source projects for a long time already including VS Code/PyCharm. I value consistency, the Atom's One Dark version I think should be the source of truth since they were the creator/pioneer of it. The fans of One Dark theme expect the same colors, regardless if it's high contrast or low contrast for other users/non-fans. They're fans for a reason. They love the exact values as is. Anyway, I'll submit a PR. Cheers