Is that only implemented for stix? Do dejavu & cm also need their own thing?

Looks like dejavu and cm require their own mappings.

Thanks for this! I think it is a great addition!

Some questions:

• Will it be clear from the documentation that this is supported? (I wasn't aware of the mathbfit command earlier so would not have guessed that was the way to obtain it.) I think a what's new note is worthwhile as well.
• Am I right in assuming that\mathbfit{foo} is the way to obtain it and that\mathbf{\mathit{foo}} is not working? Would it be possible to make it work? It seems from the tests that e.g.\mathbf{\mathsf{bar}} works?
• (Now, none of those works in standard LaTeX so maybe not a big thing if only one works.)
• Should one also add an alias for\boldsymbol which basically is a way to obtain the same result and maybe more people(?) use?

Note that apart from maybe the first bullet, these are not things that must be included in this PR. Just wanted to open the discussion.

This is probably a good location to document it:
https://matplotlib.org/stable/tutorials/text/mathtext.html#fonts

Hi@oscargus,

Thank you for the review! I have tried replying to your comments below:

• I have updated the\mathbfit command in the docs font section in a new commit from the link you shared. Thewhat's new section still needs to be updated.

• Currently,\mathbfit{bar} is the preferred way to add bold-italic font. The\mathbf{\mathit{bar}} does not apply bold-italic, just derives the innermost style to use on the text.
  At present, the\mathbfit command is deriving a stylistic change fordejavu anddejavusans fonts and the Unicode mapping forstix

• As you mentioned making a\boldsymbol alias to\mathbfit would probably be the way to go because I found that the bm package, which provides\boldsymbol command conflicts with the Unicode-math package. It can be added in a future PR.

Thanks! Would it also make sense to add it here? It seems to be working for stix right? (And then also for deja vu, but there is no special section for those I guess and maybe out of scope to add one.)

Also, for both entries here, it says "bold italic"?

I am not exactly sure how to add an alias for the\mathbfit command but I'll look into it. If you have any references I would appreciate it.

And, I believe the\mathbf command stating bold italic is incorrect as it just provides the boldface font. I can update both changes in a new commit.

I am not exactly sure how to add an alias for the\mathbfit command but I'll look into it.

I just checked the code and I do not think that there is an easy way to do that...

Probably one will have to add a special command for this, both wrt parsing and a callback.

@oscargus Per#19393 (comment), for consistency with latex, I think we should actually make\mathfoo{\mathbar{...}}not stack the styles, but just overwrite one another, and introducing\mathbfit for the stacked version seems correct.

Hi,@rcomer@oscargus@anntzer

Could you please review this patch and let me know if there are any further modifications required?

I'm afraid I don't have the expertise to review this one.

I think that the tutorial should be updated a bit further as discussed above (at least add it to the Stix section).

I'm also wondering if#mathtext.bfit:sans is the correct default rcParam, but I do not know exactly how that works. (I'd guess something like#mathtext.bfit:sans:italic:bold?)

Code-wise it looks good AFAICT.

Hi@oscargus, I have updated the PR with the suggestions. Please let me know if anything else needs to be updated.

Hi all!
Thank you for the reviews. I have made the changes and rebased to the current main.