Convert "osx" gui framework to/from "macosx" in Matplotlib (#14420)
This is a correction to the code that moves backend handling to
Matplotlib, which came to light during the review of
matplotlib/matplotlib#27948. The GUI framework of macOSX is called `osx`
in IPython but `macosx` in Matplotlib.
It would be possible to allow passing a GUI framework of `osx` to
Matplotlib and internally converting it to `macosx`, but the reverse
direction is problematic as we would like the answer to be `osx` if we
are using IPython and `macosx` if using pure Matplotlib. Therefore the
simplest solution is to do the translation in IPython. It is not ideal
as we want to minimise such Matplotlib-related implementation details in
IPython, but the changes here are small and simple and hence I think
they are acceptable.
There are two new private functions `_convert_gui_to_matplotlib` and
`_convert_gui_from_matplotlib` to do the required checking and
conversion, and these are called whenever a GUI framework name is passed
to or from Matplotlib. There are only 3 places in the code where this is
currently required.
Inevitably this comes to light just after the release of IPython 8.24.0!
But it is not a problem for end users until the next Matplotlib release
which contains matplotlib/matplotlib#27948. If that occurs really
quickly (sometime in May?) perhaps we could release an IPython 8.24.1
just beforehand, otherwise the usual planned release at the end of next
month would be fine.
Display Greek small letter mu
`%time foo()` output is often copied into code comments to explain
performance improvements. The `\xb5` Latin Extended micro sign and the
`\u03bc` Greek small letter mu have different codes but often look
identical.
Output mu to align with:
* [The International System of Units (SI) brochure](
https://www.bipm.org/documents/20126/41483022/SI-Brochure-9-EN.pdf
), such as Table 7 SI prefixes
* NFKC normalized [Python code](https://peps.python.org/pep-3131/
) and [domain names](https://unicode.org/reports/tr36/). For example:
```sh
python -c 'print("""class C:
\xb5=1
print(hex(ord(dir(C)[-1])))""")' | tee /dev/fd/2 | python -
```
```python
class C:
µ=1
print(hex(ord(dir(C)[-1])))
```
`0x3bc`
* Section 2.5 Duplicated Characters of [Unicode Technical Report 25](
https://www.unicode.org/reports/tr25/)
> ...U+03BC μ is the preferred character in a Unicode context.
* Ruff confusable mapping [updates](
https://github.com/astral-sh/ruff/pull/4430/files
), currently in the "preview" stage
Add a unit test for UTF-8 display and
https://bugs.launchpad.net/ipython/+bug/348466 ASCII fallback.
M Bussonnier
Ian Thomas
Christopher Covington