IndexError in spanish stemmer

[komod0]

When summarizing text in spanish certain words cause the summarizer to raise an Exception, ie:

from summa import summarizer
summarizer.summarize("urgue", language="spanish")

Even though the word isn't grammatically correct, raising an Exception is undesired behavior.

The problem seems to be generated in the snowballer:

textrank/summa/preprocessing/snowball.py

Lines 3505 to 3510 in d9252a2

	if rv.endswith(suffix):
	if suffix in ("e", "\xE9"):
	word = word[:-len(suffix)]
	rv = rv[:-len(suffix)]
	if word[-2:] == "gu" and rv[-1] == "u":

When the value of rv is "e" and suffix is "e".