Bug report

Bug summary

Automatic placing of legend seems to be not working with histograms of type step*. If I am correct, this is a new entry in the long list of current issues with legend ^^.

Code for reproduction

import matplotlib.pyplot as plt

hist_types = ('bar', 'barstacked', 'step', 'stepfilled')

fig, axs = plt.subplots(nrows=len(hist_types), num="test")    
for ax, ht in zip(axs.flat, hist_types):
    ax.set_title(ht)
    ax.hist([0] + 5*[9], bins=range(10), label=f"This is a label", histtype=ht)               
    ax.legend(loc="best")

fig.tight_layout()
#fig.savefig(fig.get_label() + ".png")

Actual outcome

Matplotlib 2.1

Expected outcome

The same auto-position of the legend on each subplot, i.e. upper left, whatever is the histogram style.

Matplotlib version

• Operating system: GNU/Linux (Fedora 26)
• Matplotlib version: 2.1 from conda (also test “successfully” with master)
• Matplotlib backend (print(matplotlib.get_backend())): Qt5Agg
• Python version: 3.6.3 from conda
• Jupyter version (if applicable): X
• Other libraries: X

FWIW, I tried the above snippet on Matplotlib 1.5.0 and the result is similar.

Edit: tweaked a bit the snippet to be Matplotlib v1.5.x-compliant.