Bug report

Bug summary

I'm not really sure what align=left/right is even supposed to mean for uneven bins, but at least histype=bar/stepfilled should interpret them in the same manner (or both should error out).

Code for reproduction

from pylab import *

np.random.seed(0)
t = np.random.rand(100)
fig, axs = plt.subplots(3, 2, sharex=True, sharey=True)
for i, align in enumerate(["left", "mid", "right"]):
    for j, ht in enumerate(["bar", "stepfilled"]):
        axs[i, j].hist(t, [0, 1/4, 1], histtype=ht, align=align)
        axs[i, j].set(xlabel=f"histtype={ht!r}", ylabel=f"align={align!r}")
        axs[i, j].label_outer()

plt.show()

Actual outcome

Expected outcome

Either consistent plots with both histtypes, or an error indicating that align=left/right is incompatible with uneven bins.

Matplotlib version

• Operating system:
• Matplotlib version: master
• Matplotlib backend (print(matplotlib.get_backend())):
• Python version:
• Jupyter version (if applicable):
• Other libraries:

Noted while thinking about #12493.