ycb_matplotlib_pr24149

what a new run launched now would send

[Bug]: ax.bar raises for all-nan data on matplotlib 3.6.1 
### Bug summary

`ax.bar` raises an exception in 3.6.1 when passed only nan data. This irrevocably breaks seaborn's histogram function (which draws and then removes a "phantom" bar to trip the color cycle).

### Code for reproduction

```python
import numpy as np
import matplotlib.pyplot as plt
f, ax = plt.subplots()
ax.bar([np.nan], [np.nan])
```


### Actual outcome

```python-traceback
---------------------------------------------------------------------------
StopIteration                             Traceback (most recent call last)
Cell In [1], line 4
      2 import matplotlib.pyplot as plt
      3 f, ax = plt.subplots()
----> 4 ax.bar([np.nan], [np.nan])[0].get_x()

File ~/miniconda/envs/py310/lib/python3.10/site-packages/matplotlib/__init__.py:1423, in _preprocess_data.<locals>.inner(ax, data, *args, **kwargs)
   1420 @functools.wraps(func)
   1421 def inner(ax, *args, data=None, **kwargs):
   1422     if data is None:
-> 1423         return func(ax, *map(sanitize_sequence, args), **kwargs)
   1425     bound = new_sig.bind(ax, *args, **kwargs)
   1426     auto_label = (bound.arguments.get(label_namer)
   1427                   or bound.kwargs.get(label_namer))

File ~/miniconda/envs/py310/lib/python3.10/site-packages/matplotlib/axes/_axes.py:2373, in Axes.bar(self, x, height, width, bottom, align, **kwargs)
   2371 x0 = x
   2372 x = np.asarray(self.convert_xunits(x))
-> 2373 width = self._convert_dx(width, x0, x, self.convert_xunits)
   2374 if xerr is not None:
   2375     xerr = self._convert_dx(xerr, x0, x, self.convert_xunits)

File ~/miniconda/envs/py310/lib/python3.10/site-packages/matplotlib/axes/_axes.py:2182, in Axes._convert_dx(dx, x0, xconv, convert)
   2170 try:
   2171     # attempt to add the width to x0; this works for
   2172     # datetime+timedelta, for instance
   (...)
   2179     # removes the units from unit packages like `pint` that
   2180     # wrap numpy arrays.
   2181     try:
-> 2182         x0 = cbook._safe_first_finite(x0)
   2183     except (TypeError, IndexError, KeyError):
   2184         pass

File ~/miniconda/envs/py310/lib/python3.10/site-packages/matplotlib/cbook/__init__.py:1749, in _safe_first_finite(obj, skip_nonfinite)
   1746     raise RuntimeError("matplotlib does not "
   1747                        "support generators as input")
   1748 else:
-> 1749     return next(val for val in obj if safe_isfinite(val))

StopIteration: 
```

### Expected outcome

On 3.6.0 this returns a `BarCollection` with one Rectangle, having `nan` for `x` and `height`.

### Additional information

I assume it's related to this bullet in the release notes:

- Fix barplot being empty when first element is NaN

But I don't know the context for it to investigate further (could these link to PRs?)

Further debugging:

```python
ax.bar([np.nan], [0])  # Raises
ax.bar([0], [np.nan])  # Works
```

So it's about the x position specifically.

### Operating system

Macos

### Matplotlib Version

3.6.1

### Matplotlib Backend

_No response_

### Python version

_No response_

### Jupyter version

_No response_

### Installation

pip

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