pyupgrade is a tool to automatically upgrade syntax for newer versions
of the Python language.

The project has been Python 3 only since
35544e2fc6eed0ce4a27ec7285aac71ff0ddc473, allowing for several cleanups:

- Remove unnecessary "-*- coding: utf-8 -*-" cookie. Python 3 reads all
  source files as utf-8 by default.

- Replace IOError/EnvironmentError with OSError. Python 3 unified these
  exceptions. The old names are aliases only.

- Use the Python 3 shorter super() syntax.

- Remove "utf8" argument form encode/decode. In Python 3, this value is
  the default.

- Remove "r" from open() calls. In Python 3, this value is the default.

- Remove u prefix from Unicode strings. In Python 3, all strings are
  Unicode.

- Replace io.open() with builtin open(). In Python 3, these functions
  are functionally equivalent.

Co-authored-by: Matthäus G. Chajdas <Anteru@users.noreply.github.com>

Previously, the tag was cut off.

Previously, something like:
<%class>text</%class> would not get matched correctly. This was due to
the capturing group capturing the wrong part of the tag -- instead of
class, it would capture the part after class before >. With this commit,
the capturing group correctly matches the start/end tag. This commit
also adds a unit test to verify this.

* Add analyze_text to make make check happy.

This also fixes a few small bugs:

* Slash uses *.sla as the file ending, not *.sl
* IDL has endelse, not elseelse

* Improve various analyse_text methods.

* Improve various analyse_text methods.

* Make Perl less confident in presence of :=.
* Improve brainfuck check to not parse the whole input.
* Improve Unicon by matching \self, /self
* Fix Ezhil not matching against the input text

* Simplify Modula2::analyse_text.