Improved the terminal colour formatting, Issue #11666

[FamousPond]

Hello,

This PR resolves https://github.com/pytest-dev/pytest/issues/11666.

This is my first time contributing to an open source project so please excuse any beginner mistakes.

I used the pull request https://github.com/pytest-dev/pytest/pull/11700 as an initial guide as they started to implement this issue but then stopped.

I also know that there are errors with my pull request. I believe that they are all due to do the testing of the terminal output, which I have now changed. I am not sure how to change these tests properly, so have left it for now.

What I did

My goal was to implement the use of the pygment classes TerminalTrueColorFormatter and Terminal256Formatter to get richer colours in the terminal .

To do this I used the same logic as pygments use to get the formatter that is appropriate for the users computer. https://github.com/pygments/pygments/blob/861fb9131b13241d7ea700fba8f6a38cf6f97285/pygments/cmdline.py#L448-L453C57

I set up the formatter in a way that the users can add their own style by setting the environmental variable PYTEST_THEME . I also added in default styles which will be used if PYTEST_THEME is not set.

Both TerminalTrueColorFormatter and Terminal256Formatter do not have light mode or dark mode options. I therefore created two default styles, one for each. I tried to create the styles as close as I could to the default style of TerminalFormatter. The environmental variable PYTEST_THEME_MODE sets if the light mode or dark mode default style is used. If PYTEST_THEME_MODE is not set dark mode is the default style.

To create the default styles. I made classes at the end of the terminalwiter.py file. If this is the wrong spot for them I am sorry.

Thanks, James

[FamousPond]

Regarding the DarkModeStyle and LightModeStyle, can you explain what you mean by "recreated to work with both TerminalTrueColorFormatter and Terminal256Formatter" means?

I was recreating the default light and dark mode formats that pygments uses. As seen here (although I was unsure what the '*' meant in Generic.Heading):

Using the hardcoded classes may not be the best way to go about this, so if you have a better idea let me know.

[bluetech]

@FamousPond the merge commit you pushed seemed to have removed most of your code changes, at least according to the PR's "Files changed". My recommendation is to use git rebase instead of git merge in PRs, it leads to less confusing results.

[FamousPond]

@bluetech Sorry about that. I am still learning. Ill remember that for next time. I am a bit busy at the moment but haven't forgotten about this. I will try work on it next week.