"".join(shlex.quote(...) ...) to shlex.join(...) is too eager

[Redoubts]

Consider the following:

import shlex

trash_bin = "garbage".join(shlex.quote(a) for a in ["some", "quotable strings"])

If I run pyupgrade --py310-plus on this, I get trash_bin = shlex.join(["some", "quotable strings"]). But this is not equivalent. This is a very contrived case, but there are real cases I could envision, like ", ", where one might want to keep the str.join

pyupgrade==3.15.1

[asottile]

good catch! looks like this missed a check on the actual join string